Devices and methods for precision advancing needle with sensing

Abstract

Devices and associated methods are described that provide needle extension / retraction with fine control, for in-situ needle advancement into biological spaces, thin cavities and tissues, such as those in the eye, for fluid / drug / material delivery or drainage. The device includes a distal end portion of the device with a lateral surface from which a needle extends when the lateral surface is adjacent to a biological surface, allowing injections in hard-to-reach locations, such as behind the eyelid and posterior to the superior or inferior orbital rim. In at least one embodiment, a needle advancement mechanism is also coupled to increase fluid pressure during fluid injection. In at least one embodiment light shone from the distal end portion of the device or through the needle bore helps to localize an injection site for a user looking inside the eye via changes in light intensity and / or light color depending on the needle tip depth.

Description

TITLE: Devices and Methods for Precision Advancing Needle with SensingCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 633,679 filed on April 12, 2024; U.S. Provisional Patent Application No. 63 / 670,850 filed on July 12, 2024; and U.S. Provisional Patent Application No. 63 / 726,213 filed on November 27, 2024. The complete disclosures of U.S. Provisional Patent Application No. 63 / 633,679, U.S. Provisional Patent Application No. 63 / 670,850 and U.S. Provisional Patent Application No. 63 / 726,213 are hereby incorporated by reference.FIELD

[0002] The various embodiments described herein generally relate to injection and drainage devices and methods with a moveable (e.g., extendable and / or retractable) needle for precise, accurate, and controlled delivery and / or drainage of medicants, fluids, or other substances to or from targeted locations including, but not limited to, ocular sites including the suprachoroidal and subretinal spaces accessed by penetrating through the sclera near the target location.BACKGROUND

[0003] The following paragraphs are provided by way of background to the present disclosure. They are not however an admission that anything discussed therein is prior art or part of the knowledge of a person of skill in the art.

[0004] A variety of devices and methods exist for delivering fluid or medicant to different regions of the eye via different routes during treatment of a condition. The most common among these are topical, subconjunctival, intravitreal, and subretinal routes. For many applications, these treatments are either non-localized, exposing healthy tissue to the drug and requiring larger doses, or involve invasive procedures.

[0005] In recent years, delivery of fluid or medicant via the suprachoroidal space (SCS) has been explored as an alternative to these traditional methods of treatment for a wide range of diseases, including macular edema, age-related macular degeneration, non-infectious uveitis, hereditary retinal diseases, and glaucoma. Suprachoroidal injections offer greater localization of injected medicant while in some cases being less invasive. In addition, there is a desire to be able to deliver a fluid ormedicant to the subretinal space (SRS) between the retina and choroid in a less invasive manner.

[0006] The SCS is a potential space between the sclera and choroid of the eye. Though the sclera and choroid are adjacent tissues, their functions and mechanical properties are vastly different. The sclera is a tough, collagenous tissue that supports and protects the eye, while the choroid is a highly vascular layer that supplies blood and nutrients to the retina. When a positive pressure is introduced between these two layers, the choroid pulls away from the sclera and a pocket of flu id, or “bleb”, is created. If left, this fluid may disperse circumferentially around the eye in the SCS and be absorbed by surrounding tissues over time. The rate of closure or reduction of the space depends on the viscosity and other properties of the injected fluid [1], Agents with higher viscosity induce slower closure / reduction rates [2],

[0007] Two main classes of device exist for accessing the SCS: catheters and microneedles. Catheterization often requires an operating room environment and is more invasive than needle-based procedures; however, it currently allows for greater access to the posterior regions of the eye, which are inaccessible by traditional needlebased devices. However, these surgical techniques may have a steep learning curve and greater risk of choroidal hemorrhage from tunneling between the sclera and choroid. Microneedles are small needles that are short, have a fixed-length and are exposed to decrease risk of puncturing into or through the choroid. Drug injection via microneedles is much less invasive and can more easily be done in a doctor’s office, making it the preferred route of treatment but this is limited to injections at anterior locations based on conventional drug delivery devices.

[0008] No current device allows for trans-scleral minimally invasive delivery or drainage of a fluid into orfrom the SCS or delivery of a fluid to the SRS while accessing more posterior regions of the eye in a localized manner. For most drug delivery applications, an injection via microneedle near the front of the eye relies on dispersion of the non-viscous fluid throughout the SCS to reach the back of the eye. This is not ideal, since the drug is not delivered specifically to the target location, such as the macula. Additionally, there may be some applications where precise placement of the fluid is critical, such as for the treatment of retinal detachment or myopic fractional maculopathy.

[0009] In-Office Suprachoroidal Viscopexy (SCV) is a minimally invasive technique recently developed for treating rhegmatogenous retinal detachment [3], The SCVtechnique has the potential to greatly reduce the cost and recovery time of retinal detachment repair while also improving the quality of the repair and reducing morbidity. It can be performed with no incision, no tamponade agent, and no patient post-operative positioning requirements [3], SCV works by injecting viscous fluid into the SCS, creating a “bleb” of fluid underneath the tear that pushes the choroid towards the retina and allows it to reattach. A safe and reliable device for performing the SCV technique may greatly change how retinal detachments are treated and improve patient outcomes.

[0010] While there exists great potential for suprachoroidal delivery of medications or drugs or other agents to improve patient outcomes for many conditions, there are also risks that must be minimized in order for it to be widely adopted. Scleral thickness varies from patient to patient and between different locations on the same eye, thus, it is difficult to predict the ideal length of needle necessary for a given procedure. The margin for error in needle length is very small, as the sclera ranges in thickness from about 0.5-1.3 mm and the choroid ranges in thickness from about 0.15-0.3 mm [4, 5], The risk associated with hemorrhage from puncturing through the choroid is high, especially in posterior regions of the eye where the choroid is especially vascular. Puncturing a blood vessel in the choroid may result in a hemorrhage that may lead to vision loss.

[0011] Accordingly, there is a need for a device that can be used to perform suprachoroidal delivery, SCV, and other ocular procedures such as SRS drug delivery that is easy to use and provides for precise localization and delivery of injection agents and / or drainage (e.g., of fluids and / or materials / devices).SUMMARY OF VARIOUS EMBODIMENTS

[0012] Various embodiments are described herein of devices and related methods for injection and drainage of fluids or other agents utilizing an extendable / retractable needle for precise, accurate, and controlled delivery and / or drainage of medicants, fluids, or other substances to or from targeted locations including, but not limited to, ocular sites including the suprachoroidal and subretinal spaces. This may involve precisely controlling the advancement of a needle with enough resolution to a target location such as potential spaces, cavities, and thin tissues within the body, such as the SCS and the SRS in the eye, for example.

[0013] In one aspect, in accordance with the teachings herein, there is provided at least one embodiment of a device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device; a moveable needle disposed at the distal end portion of the device; a needle holding member that is disposed within the housing, the needle holder being moveable and the needle being located at a distal end portion of the needle holding member; and a needle movement control mechanism coupled to the needle holding member, the needle movement control mechanism being actuatable to cause the needle holding member to extend the needle through a needle exit location on a lateral surface of the distal end portion of the device, at an angle to a longitudinal axis of the distal end portion of the device.

[0014] In at least one embodiment, the needle movement control mechanism is also reversibly actuatable to retract the needle into the housing.

[0015] In at least one embodiment, an angular orientation of the needle at it is extended from the lateral surface of the distal end portion of the device ranges from about 45 degrees to about 135 degrees with respect to a plane tangent to the lateral surface at the needle exit location.

[0016] In at least one embodiment, the angular orientation of the needle as it is extended from the lateral surface of the distal end portion of the device is about 90 degrees with respect to the plane tangent to the lateral surface at the needle exit location.

[0017] In at least one embodiment, the lateral surface of the distal end portion of the device has a flat portion or a curved portion.

[0018] In at least one embodiment, a portion surrounding the needle exit location on the lateral surface of the distal end portion of the device is concave to conform to an outer surface of the eye.

[0019] In at least one embodiment, a portion surrounding the needle exit location on the lateral surface of the distal end portion of the device is convex to indent an outer surface of the eye.

[0020] In at least one embodiment, wherein a radius of curvature of the lateral surface of the distal end portion of the device matches a radius of curvature to within 20% of a location of the target where the needle is inserted.

[0021] In at least one embodiment the lateral surface of the distal end portion of the device is curved has an arc angle between about 5 degrees to about 90 degrees.

[0022] In at least one embodiment, the lateral surface of the distal end portion of the device is curved and has an arc angle between about 30 degrees to about 60 degrees.

[0023] In at least one embodiment, a longitudinal axis of the distal end portion of the device at a region intersecting with a longitudinal axis of the main body has a negative tilt angle with respect to the longitudinal axis of the main body.

[0024] In at least one embodiment, the tilt angle is between about 0 and about -90 degrees and the title angle is more preferably about -30 degrees.

[0025] In at least one embodiment, a portion of the needle movement control mechanism is disposed on the housing and includes a rotational dial, knob, button, or wheel.

[0026] In at least one embodiment, the needle movement control mechanism is coupled to a portion of the needle holding member via a cam and the cam is rotatable to cause the needle holding member to move when the needle movement control mechanism is actuated.

[0027] In at least one embodiment, the needle holding member is in a simply supported arrangement where a proximal end portion of the needle holding member is fixed.

[0028] In at least one embodiment, the device further comprises a slot actuating member that has an angled slot at a distal end portion thereof and the needle holding member has a pin at the distal end portion that slidably engages the slot so that when the slot actuating member is moved, the pin moves along the slot causing the distal end portion of the needle holding member to move causing the needle to move.

[0029] In at least one embodiment, the slot has straight segments with different angles that causes the needle to move at a faster or slower rate when the pin moves through the segments depending on curvature of the curved segment.

[0030] In at least one embodiment, the slot has a curved segment that causes the needle to move at a faster or slower rate when the pin moves through the curved segment.

[0031] In at least one embodiment, the needle movement control mechanism is coupled to a proximal portion of the needle holding member via a cam so that rotation of the cam during actuation of the needle movement control mechanism causes the slot actuating member to move.

[0032] In at least one embodiment, the needle holding member includes a pivoting mechanism where a position of a proximal end portion of the needle holding member is controlled by the needle movement control mechanism and a pivot point is located adjacent a distal end portion of the needle holding member, wherein movement of the proximal end portion of the needle holding member causes the needle to move.

[0033] In at least one embodiment, the needle holding member has a pivot (e.g., pin member) that is located between the distal and proximal end portions of the needle holding member and supported by a pivot bore in the housing such that when a proximal end portion of the needle holding member receives a displacing force or displacement input when the needle movement control mechanism is actuated the distal end portion of the needle holding member is moved causing the needle to move.

[0034] In at least one embodiment, the needle holding member is an elastically deformable beam having a proximal end portion and a distal end portion, wherein the proximal end portion is prevented from displacing, and a pivot support is located between the proximal and distal end portions, wherein when an actuating force is applied to the beam between the pivot support and the proximal end portion, the distal end portion is displaced to cause the needle to move.

[0035] In at least one embodiment, the elastically deformable beam has a medial portion that extends from the pivot to an actuating force location where the distal end and medial portions are stiffer than the proximal end portion of the needle holding member to reduce deflection of the needle under needle insertion forces, where the deflection due to the needle holding member at the base of the needle is less than 30% of an intended total motion of the needle tip.

[0036] In at least one embodiment, the needle movement control mechanism includes a wheel having a cam and the proximal portion of the needle holding member includes a cam-engagement structure so when the needle movement control mechanism is actuated, the wheel and the cam rotate and thereby move the proximal end portion of the needle holding member.

[0037] In at least one embodiment, the needle movement control mechanism includes a split wheel having two opposing wheel halves and a cam located therebetween and coupled to the wheel halves, and the proximal portion of the needle holding member is shaped to fit between the wheel halves and be adjacent to the cam so that when the needle movement control mechanism is actuated, the wheel and the cam rotate to move the proximal end portion of the needle holding member.

[0038] In at least one embodiment, the needle movement control mechanism includes a wheel with a central axis of rotation and a spiral slot on a side face and the proximal portion of the needle holding member includes a slot engagement member (e.g., a pin) at a proximal end portion where the pin slidably engages the spiral slot and when the needle movement control mechanism is actuated, the spiral slot rotates causing the pin to move laterally thereby moving the proximal end portion of the needle holding member.

[0039] In at least one embodiment, the needle movement control mechanism includes a split wheel having two opposing wheel halves each having a common axis of rotation and spiral cam slot on a side face, the slots facing each other, the proximal end portion of the needle holding member is disposed between the wheel halves and includes a slot engagement member (e.g., a pin) that slidably engages the spiral slots and the main body and when the needle movement control mechanism is actuated, the spiral slots rotate about the common axis and the pin is moved laterally thereby applying a displacing force to the proximal end portion of the needle holding member.

[0040] In at least one embodiment, the needle movement control mechanism includes a wheel having bumps, slots, depressions or other physical indicators (herein referred to as “bumps”) around a circumference thereof to provide traction and tactile feel to a user of the device as the user rotates the wheel to actuate the needle.

[0041] In at least one embodiment, the bumps vary in width and / or circumferential length from small to large over a rotation range of the wheel to provide tactile feedback to the user as to a distance the needle is protruding from the lateral surface of the distal end portion of the device.

[0042] In at least one embodiment, the needle movement control mechanism includes a wheel having a cam and the proximal end portion of the needle holding member has a contact member that engages the cam so that when the needle movement control mechanism is actuated, the cam rotates to apply force to the contact member of the proximal end portion of the needle holding member to move the needle holding member.

[0043] In at least one embodiment, the needle movement control mechanism includes a wheel having a cam and the proximal end portion of the needle holding member has a lever mechanism having a proximal end that engages the cam such that movement of the cam causes the needle holding mechanism and the needle to move in response.

[0044] In at least one embodiment, the needle movement control mechanism includes visual distance measures to indicate how far the needle tip is advanced when the needle movement control mechanism is actuated.

[0045] In at least one embodiment, the needle movement control mechanism includes a ratchet mechanism provided by a rounded or tapered protrusion on the wheel that contacts an extended semi-flexible member attached to the main body which provides resistance to turning the wheel but also yields and allows further movement to provide a user with tactile feedback when actuating the needle movement control mechanism.

[0046] In at least one embodiment, the ratcheting mechanism is a reversible ratchet to allow for retraction of the needle.

[0047] In at least one embodiment, a distal end portion of the needle holding member has a greater thickness and is stiffer than a medial portion of the needle holding member.

[0048] In at least one embodiment, the device further comprises a treatment fluid container and optionally a drainage chamber.

[0049] In at least one embodiment, the treatment fluid container (e.g., a vial) is coupled to the needle holding member so that movement of the needle holding member to advance the needle also causes an increase in fluid injection pressure.

[0050] In at least one embodiment, the device further comprises a fluid control mechanism for fluid injection and / or drainage.

[0051] In at least one embodiment, wherein the treatment fluid container is coupled to the needle holding member via an elastic element that is positioned therebetween and a mechanical element that is moved by a control input.

[0052] In at least one embodiment, the treatment fluid container contains a viscoelastic fluid or a therapeutic drug to be delivered to the target, the targeting being a desired location within a patient.

[0053] In at least one embodiment, the fluid control mechanism is a mechanical slider, button, wheel, or electrically powered motor actuated extendable member that is coupled to an internal plunger of the device to push fluid out of the treatment fluid container and into the needle to be delivered to the target.

[0054] In at least one embodiment, the device further comprises a light pipe or an optical fiber that extends to a distal end portion of the device, where a light source is coupled to the light pipe or the optical fiber.

[0055] In at least one embodiment, the device comprises a fluid pipe that extends to a distal end portion of the device and is coupled to the needle where the fluid pipe is used to deliver treatment fluid to the needle or receive drainage elements from the needle.

[0056] In at least one embodiment, the fluid pipe and the light pipe or an optical fiber are delivered to the needle through a single diameter or a stepped passageway of successively smaller diameters.

[0057] In at least one embodiment, wherein the device includes a mirror, a prism or a photonic crystal and when the needle is oriented to be inserted into the eye, the mirror, prism or photonic crystal is used to efficiently redirect light from projecting along the main body of the device to project inside the needle as the needle is moved through the lateral surface of the distal end portion of the device for insertion into the sclera.

[0058] In at least one embodiment, the fluid pipe is used as the light pipe, using reflection from internal walls of the needle to guide light.

[0059] In at least one embodiment, a hollow optical waveguide acts as the fluid pipe and the light pipe.

[0060] In at least one embodiment, a distal portion of the fluid pipe is tapered.

[0061] In at least one embodiment, the device includes the light source that is optically coupled to the light pipe or the optical fiber.

[0062] In at least one embodiment, the light source is internal or external to the main body of the device.

[0063] In at least one embodiment, the light source is configured to generate a light at the distal end portion of the device which indicates to an operator a location of the device distal end portion of the device relative to the target.

[0064] In at least one embodiment, the distal end portion of the device includes at least one protrusion on the lateral surface at the end portion of the device and the needle is extended through the at least one protrusion.

[0065] In at least one embodiment, the device is separable into a proximal portion or back-end housing and a distal portion or front-end housing, wherein the back-end housing houses the vial, fluid control mechanism, and electronics and the front end houses the needle holding member and the needle.

[0066] In at least one embodiment, the device comprises a tip sub-assembly that is releasably connectable to a distal end of a lower portion of the main body of the device.

[0067] In at least one embodiment, the device comprises a suction channel at the lateral surface of the distal end portion of the device to apply suction to a surface of the target during needle insertion into the target.

[0068] In at least one embodiment, the suction channel is coupled to at least one suction aperture on the lateral surface of the distal end portion of the device.

[0069] In at least one embodiment, the suction channel is coupled to a plurality of suction apertures disposed about the needle exit location on the lateral surface of the distal end portion of the device.

[0070] In at least one embodiment, a positive pressure is applied to an aperture at the needle exit location that the needle is extended through to apply positive pressure to the surface of the target at needle insertion.

[0071] In at least one embodiment, the device comprises a reflective coating inside a bore of the needle to enable the bore of the needle to function as a light pipe for transmitting light along the needle.

[0072] In at least one embodiment, the device comprises a raised surface (e.g., a “mesa”) at the exit needle location on the lateral surface of the distal end portion of the main device, such that when a user presses the raised surface against the sclera, a tension is created in a sclera surface to enable the needle to more easily penetrate into the sclera with less pushing away (e.g., “tenting”) of the sclera.

[0073] In at least one embodiment, the device comprises an empty syringe at atmospheric pressure, a syringe with a plunger, or a syringe attached to a suction machine configured to attach to a drainage needle path for draining fluid out of the target.

[0074] In at least one embodiment, the device comprises a motorized needle advancement assembly for moving the needle with respect to the lateral surface at the distal end portion of the device.

[0075] In at least one embodiment, the device comprises a motor for actuating fluid delivery, a sensor for sensing a change in magnitude of current drawn by the motor due to changing torque based on fluid flow, and a sensor for sensing a change in frequency of the current drawn by the motor due to back Electromotive Force (EMF) due to change in motor speed due to changing fluid pressure and a controller for receiving sensor signals indicating any changes in the magnitude and frequency of the current drawn by the motor.

[0076] In at least one embodiment, the controller is adapted to provide alerts corresponding to changes in fluid flow and fluid pressure based on the measured changes of the magnitude and the frequency of current drawn by the motor, respectively.

[0077] In another aspect, in accordance with the teachings herein, there is provided a device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device; a moveable needle disposed at the distal end portion of the device; and a suction channel disposed at the distal end portion of the device to apply suction to a surface of the target during needle insertion into the target.

[0078] In at least one embodiment, the suction channel is coupled to at least one suction aperture on the lateral surface of the distal end portion of the device.

[0079] In at least one embodiment, the suction channel is coupled to a plurality of suction apertures disposed about the needle exit location on the lateral surface of the distal end portion of the device.

[0080] In at least one embodiment, a positive pressure is applied to an aperture at the needle exit location that the needle is extended through to apply positive pressure to the surface of the target at needle insertion.

[0081] In at least one embodiment, the device further comprises: a needle holding member that is disposed within the housing, the needle holder being moveable and the needle being located at a distal end portion of the needle holding member; and a needle movement control mechanism coupled to the needle holding member, the needle movement control mechanism being actuatable to cause the needle holding member to extend the needle through a needle exit location on a lateral surface of the distal end portion of the device at an angle to a longitudinal axis of the distal end portion of the device, wherein the device is further defined according to one or more of the embodiments described herein.

[0082] In another aspect, in accordance with the teachings herein, there is provide a device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device; a moveable needle disposed at the distal end portion of the device; a needle holding member that is disposed within the housing, the needle holder being moveable and the needle being located at a distal end portion of the needle holding member; a fluid delivery assembly for injecting a treatment fluid into the target, and a needle movementcontrol mechanism coupled to the needle holding member and the fluid delivery assembly, wherein the needle movement control mechanism is actuatable to cause the needle holding member to move the needle through a needle exit location into the target and to cause the fluid delivery assembly to deliver the treatment fluid to the needle.

[0083] In at least one embodiment, the needle exit location is on a lateral surface of the distal end portion of the device and the device is further defined according to one or more of the embodiments described herein.

[0084]

[0085] In another aspect, in accordance with the teachings herein, there is provided a use of a device for treating retinal tear or retinal detachment, wherein the device is defined according to any one of the embodiments described herein.

[0086] It will be appreciated that the foregoing summary sets out representative aspects of embodiments to assist skilled readers in understanding the following detailed description. Other features and advantages of the present application will become apparent from the following detailed description taken together with the accompanying drawings. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the application, are given by way of illustration only, since various changes and modifications within the spirit and scope of the application will become apparent to those skilled in the art from this detailed description.BRIEF DESCRIPTION OF THE DRAWINGS

[0087] For a better understanding of the various embodiments described herein, and to show more clearly how these various embodiments may be carried into effect, reference will be made, by way of example, to the accompanying drawings which show at least one example embodiment, and which are now described. The drawings are not intended to limit the scope of the teachings described herein.

[0088] FIG. 1 is a section view of the human eye with a retinal detachment and an embodiment of a device with a tip having a needle that is extended to protrude into the SCS.

[0089] FIG. 2 shows the SCV procedure where viscous fluid is injected into the SCS to create a bleb.

[0090] FIG. 3 illustrates how traditional straight needles cannot reach posterior regions of the eye with a straight entry.

[0091] FIG. 4 depicts how a physician might hold one embodiment of a device that is in accordance with the teachings herein for reaching a region of the eye that is not easily accessible with conventional devices.

[0092] FIG. 5 shows how the tip of an example embodiment of a device in accordance with the teachings herein may be adapted to match the curvature of the eye.

[0093] FIGS. 6A-6C depict several example embodiments of devices in accordance with the teachings herein with distal ends having different arc angles and how larger arc angles may be used to reach further back around the eye.

[0094] FIGS. 7A-7C depict several views of an example embodiment of a device in accordance with the teachings herein having a distal end portion that is tilted at a negative tilt angle to allow placement at locations toward the front (e.g. anterior) of the eye with less chance of obstructing a user’s view through the pupil into the eye to observe where the needle will be entering the eye as illuminated by the light source projecting from the distal end of the device.

[0095] FIG. 8 is a close-up view of an example embodiment of a device in accordance with the teachings herein having a distal end portion tip with a raised surface (e.g., a “mesa”, a bump or other protrusion also known as a boss) that may be used to visualize the injection location from inside the eye as when the user presses the protrusion against the sclera, it creates a bump on the inside of the eye that may be seen by the user looking through the pupil.

[0096] FIG. 9 is an isometric view of the outside of an example embodiment of a device in accordance with the teachings herein.

[0097] FIG. 10A-10C show various example embodiments of needle tips that may be used with the devices described herein where the distance (“depth”) the needle tip extends just past the sclera for injecting fluid to, for example, cause the choroid to separate from the sclera, is different for different bevel angles of the needle tip.

[0098] FIGS. 11 A, 11 B and 11 C are a rear (backside) view, a magnified rear view and a sectional view of a distal portion of an example embodiment of a device in accordance with the teachings herein where the sectional view shows a beam that may be used to hold the needle as well as fluid and light paths.

[0099] FIG. 12 shows a small angle deflection of an example embodiment of an elastic cantilevered beam with a needle at the end of the beam where the beam can be used in various device embodiments described herein.

[0100] FIG. 13 shows the bending of an elastic beam fixed at the proximal end and simply supported between the proximal and distal ands and the needle at the distal end of the beam.

[0101] FIG. 14 shows an example of a flexure structure where an axial force is applied along a member connected to the tip of a cantilevered beam member to bend the cantilever member to cause needle motion normal to the cantilever member’s distal end.

[0102] FIGS. 15A-15D show an example of a pin in a slot that may be used to actuate a needle to move through the lateral surface of the device.

[0103] FIGS. 16A-16C show an exploded front view, a side view and perspective view, respectively, of the needle actuation elements in the slot embodiment.

[0104] FIG. 17A-17B show a front and a side view, respectively, of a simply supported member embodiment with a cutout in the beam for a control knob.

[0105] FIGS. 18A-18E is a series of views of another example of a simply supported member embodiment with the control knob split in half to allow the beam to pass through.

[0106] FIGS. 19A-19B show front and cross-sectional side views of an example embodiment of a device with a pivoting needle holding member with a pivot point at the distal end and proximal end driven by a pin in a spiral slot in the control knob.

[0107] FIGS. 20A-20B are side and front views of an example embodiment of a flexure and pivoting member that may be used to actuate a needle with a split control knob and cam in the middle.

[0108] FIGS. 20C-20D are rear and cross-sectional side views of a device that uses the flexure and pivoting member of FIGS. 20A-20B.

[0109] FIGS. 21A-21C show side, front and cross-sectional side views of an example embodiment of a flexure configuration for the needle holding member with a pin and lever at the proximal end driven by a cam.

[0110] FIGS. 22A-22C show a front view, a magnified front view of a knob, and a cross-sectional view of the knob, respectively, for an example embodiment of a tactile ratchet mechanism for a needle actuation knob.

[0111] FIGS. 23A-23B shows a top-down view and a cross-sectional sectional view, respectively, of an example embodiment of the needle holding member and actuating body when arranged in a concentric fashion with respect to the outer wall of the device.

[0112] FIGS. 24A-24F shows a series of views of the Finite Element Analysis (FEA) analysis setup of example embodiments of two simply supported needle holding members.

[0113] FIG. 25 shows a schematic of a fluid coupling design.

[0114] FIGS. 26A-26C show a front view, a magnified front view and a section view of an example embodiment of a device having a cam that interacts with an actuating slot body and an elastic element which pressurizes a fluid ampoule during device operation.

[0115] FIG. 27 shows an alternative embodiment of a device having a simply supported beam for the needle holding member with an intermediary elastic element for actuating a needle and dispensing fluid.

[0116] FIG. 28 is a see-through image showing an example of a cam’s interaction with a simply supported needle holding member and fluid ampoule, without an intermediary elastic element, in an example embodiment of a device.

[0117] FIGS. 29A and 29B show a front view and cross-sectional view, respectively, of an alternative example embodiment of a device with a flexure configuration for the needle holding member with fluid coupling through a separate body with a pin in a spiral slot in the control knob which moves upwards as the needle is deployed.

[0118] FIGS. 30A-30C show a perspective view of an example embodiment of a device with a portion of the housing removed, a cross-sectional view of the device with the needle in a partly extended position and a cross-sectional view of the device with the needle in a fully extended position, respectively.

[0119] FIGS. 31A-31C are a front view, a magnified front view and a cross- sectional view of an example embodiment of a device having a fluid slider, a plunger, and other proximal components.

[0120] FIGS. 32A-32B are a front perspective view and a magnified front perspective view, respectively, of an example embodiment of a slider ratchet that may be used with one or more of the devices described herein.

[0121] FIGS. 33A-33B are a front view and a magnified front view of another example embodiment of a ratchet and pawl that may be used with one or more of the devices described herein where the ratchet is on the sides of the slider rather than the top which may prevent back driving.

[0122] FIGS. 34A-34B show front and cross-sectional views, respectively, of an example embodiment of a distal end of the needle holding member that may be used with one or more of the devices described herein where the needle holding member includes a reflective element and light and fluid channels entering axially.

[0123] FIGS. 35A-35B show front perspective and top views, respectively, of another example embodiment of a distal end of the needle holding member that may be used with one or more of the devices described herein where the needle holding member has a light pipe and / or fluid pipe inserted from the side.

[0124] FIGS. 36A-36B show side and cross-sectional end views of an example embodiment of a distal end portion of a needle holding member having a fiber optic cable in the needle bore.

[0125] FIGS. 37A-37B show exploded perspective and front views of an example embodiment of a device in accordance with the teachings herein that incorporates components shown in FIGS. 12, 15A-15B, 16A-16C and 26A-26C.

[0126] FIGS. 38A-38B show exploded perspective and front views of an example embodiment of a device in accordance with the teachings herein that incorporate a flexure configuration of the needle holding member and lever components shown in FIGS. 14, 21A-21C, and 29A-29B.

[0127] FIGS. 39A-39B show exploded perspective and front views of an example embodiment of a device in accordance with the teachings herein that incorporate a pivoting beam for the needle holding member and crank and slider components shown in FIGS. 19A-19B and 30A-30C.

[0128] FIG. 40 shows a flow chart of an example embodiment of a method for operating one of the device embodiments described herein.

[0129] FIGS. 41A-41 E show front, magnified front, rear, side cross-sectional and perspective views, respectively, of an example embodiment of a device with a fluid path built into needle holding member with a short straight needle connected at the distal end portion and a flexible fluid path at the proximal end portion to connect to a fluid source such as a fluid ampoule.

[0130] FIGS. 42A-42C show front, magnified front and side cross-sectional views, respectively, of an example embodiment of a tapered fluid path built into the needle holding member.

[0131] FIGS. 43A-43C show a side view, a magnified upper side view and a magnified lower side view of an example embodiment of a bent needle for use with the devices taught herein.

[0132] FIGS. 43D-43G show side, front, cross-sectional side and magnified lower side views, respectively, of an example embodiment of another bent needle for use with the devices taught herein.

[0133] FIGS. 44A-44C show perspective, front, and magnified front views, respectively, of an example device embodiment that is coupled with a snap fit portion and has a loading hole to insert a pre-bent needle into the needle holding beam.

[0134] FIG. 44D shows a front view of a snap fit portion that may be coupled with the device of FIGS. 44A-44C.

[0135] FIGS. 44E and 44F depict a front view of an example embodiment of a needle holding member and a cross-sectional view of the needle holding member for a pre-bent needle being inserted therein.

[0136] FIGS. 45A-45C are perspective, top and side cross-sectional views, respectively, of an example embodiment of a tip sub-assembly for a needle holding member where the tip sub-assembly has an integrated 3D printed needle and a tapered inside channel and in the perspective and top views the outer housing of the tip sub-assembly is transparent.

[0137] FIGS. 46A-46B illustrate front and magnified views, respectively, of an example embodiment of a device with a fiber optic cable and a needle inserted into a larger needle / tube interface and fluid path for a needle holding member for use with one or more of the device embodiments herein.

[0138] FIGS. 47A-47C show perspective, front and side cross-sectional views, respectively, of an example device embodiment with a preloading spring for manual operation of the fluid injection.

[0139] FIGS. 48A-48D are perspective, front, side cross-sectional and magnified side-cross sectional views, respectively, of an example device embodiment with motorized operation of the fluid injection using a button control and with a light coupled to the needle bore.

[0140] FIGS. 49A-49C are perspective, front and side cross-sectional views, respectively, of another example device embodiment with motorized operation of the fluid injection using a slider control, and with a light couple to the needle bore.

[0141] FIGS. 50A-50C are front, upper perspective and lower perspective views, respectively, of a version of the example device embodiment from FIGS. 48A-48C that has a handle / proximal half that is separable (e.g. removably connectable) from a distal half / tip.

[0142] FIGS. 51A-51 E are rear perspective, front, upper front perspective, lower front perspective and magnified lower front perspective views, respectively, depicting a version of the example device embodiment in FIGS. 49A-49C that has a handle / proximal half that is separable (e.g., removably connectable) from a distal half / tip.

[0143] FIGS. 52A-52B are front and magnified side views, respectively, of an example device embodiment with motorized needle actuation.

[0144] FIG. 53A illustrates several flow charts for the operational flow for the controls in at least one example embodiment of a device with motorized fluid actuation.

[0145] FIG. 53B is an electronic diagram for an example embodiment with a motor and sensor control with no microcontroller that may be used with at least one of the device embodiments described herein.

[0146] FIG. 53C is an electronic diagram for another example embodiment with a motor and sensor control with a microcontroller that may be used with one of the device embodiments described herein.

[0147] FIGS. 54A-54B are rear perspective and side views, respectively, of an example embodiment of a tip sub-assembly with an integrated vacuum path (also known as (aka) a channel or a conduit) that may be used in at least one of the device embodiments described herein.

[0148] FIGS. 55A-55B are rear perspective and side cross-sectional views, respectively, of an example embodiment of a tip sub-assembly with integrated needle, fiber optic, and vacuum path (aka a channel or a conduit) that may be used in at least one of the device embodiments described herein.

[0149] FIG. 56 shows a perspective view of an example embodiment of a seal / gasket that may be used to provide a vacuum seal for use with certain sub-tip modules described herein.

[0150] FIG. 57 shows an example device embodiment configured to provide the operator with force feedback for fluid pressure when using motorized fluid actuation.

[0151] FIG. 58A is a cross-sectional view of an example embodiment of a device with a tip sub-assembly that is in contact with the conjunctiva and sclera layer of the eye during use.

[0152] FIG. 58B is an upper perspective view showing a housing posterior connection region with a kinematic interface feature for the tip sub-assembly of FIG. 58A.

[0153] FIG. 58C is an exploded view of the tip sub-assembly of FIG. 58A.

[0154] FIG. 59A shows a needle member isometric view showing axle, bore, and tip regions.

[0155] FIG. 59B shows an enlarged view of the tip of the needle member of FIG. 59A.

[0156] FIG. 59C shows a cross-section view of the needle member of FIG. 59A.

[0157] FIG. 59D shows an example embodiment of an asymmetric needle tip that may be used for the needle member of FIGS. 59A-C.

[0158] FIG. 59E shows an example embodiment of a three-point irregular contact needle tip that may be used for the needle member of FIGS. 59A-C.

[0159] FIG. 59F shows an example embodiment of a three-point regular contact that may be used for the needle member of FIGS. 59A-C.

[0160] FIG. 59G shows an example embodiment of a two-point contact needle tip that may be used for the needle member of FIGS. 59A-C.

[0161] FIGS. 60A-60B show perspective and magnified perspective views of an example embodiment of a single-gauge needle pivot lever member that may be used as the needle holding member for some of the devices described herein.

[0162] FIGS. 60C-60D show an exploded perspective view and a magnified lower exploded perspective view of the needle pivot lever member of FIGS. 60A-60B.

[0163] FIGS. 60E-60J show side, front, rear, top, cross-sectional side and rear perspective views, respectively, of a needle holder of the needle holding member of FIGS. 60A-60D.

[0164] FIGS. 61 A-61 N show various views of an example embodiment of a needle assembly having an oval tip lever assembly.

[0165] FIGS. 62A-62E show perspective, side, front, rear, and cross-sectional side, views of an example embodiment of a tip sub-assembly with the needle assembly of FIGS. 61A-61 N.

[0166] FIGS. 62F-62G shows magnified cross-sectional side views of the tip subassembly of FIGS. 62A-62E with the needle assembly of FIGS. 61A-61 N where the needle is in retracted and extended positions, respectively.

[0167] FIGS. 62H-62K show perspective, side, end and cross-sectional side views of the tip sub-assembly of FIGS. 61 A-61 E without a needle assembly.

[0168] FIGS. 62A-62C show perspective, front and side views of an example embodiment of a device having multiple suction apertures for applying a vacuum.

[0169] FIGS. 62D-62F are magnified views of a distal end portion of the device shown in FIGS. 62A-62C, respectively.

[0170] FIG. 62G is a perspective view of a distal end portion of another example embodiment of a device that uses multiple suction apertures for applying a vacuum pressure.

[0171] FIGS. 62H-62I show front and perspective views of a distal end portion of another example embodiment of a device that uses multiple suction apertures for applying a vacuum pressure.

[0172] FIGS. 63A-63C show perspective, front and side views, respectively, of an example embodiment of a device with a light source (e.g., LED) at the distal end portion.

[0173] FIGS. 63D-63F are magnified views of the distal end portion shown in FIGS. 63A-63C, respectively.

[0174] FIG. 64A shows an example embodiment of a needle that may be used with one of the devices described herein.

[0175] FIGS. 64B-64C shows perspective and side views, respectively, of another example embodiment of a needle that may be used with one of the devices described herein.

[0176] FIGS. 65A-65C how side, front and sectional views, respectively, of an example embodiment of a device having a worm gear coupled to a motor shaft and a gear of the control wheel.

[0177] FIGS. 66A-66D show side, front, perspective and sectional views of the end portion of an example embodiment of a drainage device.

[0178] FIGS. 67A-67D show side, front, perspective and cross-sectional views of another example embodiment of a drainage device.

[0179] FIGS. 68A-68E show rear, side, rear-perspective, front, cross-sectional side, front-perspective and magnified views, respectively, of another example embodiment of a device.

[0180] FIG. 69 shows measured current and voltage for a motor that controls a plunger for fluid injection with a force.

[0181] Further aspects and features of the example embodiments described herein will appear from the following description taken together with the accompanying drawings.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0182] The headings and Abstract of the Disclosure provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.

[0183] Various embodiments in accordance with the teachings herein will be described below to provide examples of at least one embodiment of the claimed subject matter. No embodiment described herein limits any claimed subject matter. The claimed subject matter is not limited to devices, systems or methods having all of the features of any one of the devices, systems or methods described below or to features common to multiple or all of the devices, systems or methods described herein. It is possible that there may be a device, system or method described herein that is not an embodiment of any claimed subject matter. Any subject matter that is described herein that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicants, inventors or owners do not intend to abandon, disclaim or dedicate to the public any such subject matter by its disclosure in this document.

[0184] Furthermore, it will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements or steps. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures and components have not been described in detail so as not to obscure the embodiments describedherein. Also, the description is not to be considered as limiting the scope of the embodiments described herein.

[0185] It should also be noted that the terms “coupled” or “coupling” as used herein can have several different meanings depending on the context in which these terms are used. For example, the terms “coupled” or “coupling” can have a mechanical, electrical or communicative connotation; such as indicating that two elements or devices can be directly connected to one another or connected to one another through one or more intermediate elements or devices via an electrical element, an electrical signal, a light signal or a mechanical element depending on the particular context.

[0186] Similarly, throughout this specification and the appended claims the term “communicative” as in “communicative pathway”, “communicative coupling”, and in variants such as “communicatively coupled” is generally used to refer to any engineered arrangement for transferring and / or exchanging information. Examples of communicative pathways include, but are not limited to, electrically conductive pathways (e.g., electrically conductive wires, physiological signal conduction), electromagnetically radiative pathways (e.g., radio waves, optical signals, etc.), or any combination thereof. Examples of communicative couplings include, but are not limited to, electrical couplings, magnetic couplings, radio couplings, optical couplings or any combination thereof.

[0187] Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is, as “including, but not limited to”.

[0188] It should also be noted that, as used herein, the wording “and / or” is intended to represent an inclusive-or. That is, “X and / or Y” is intended to mean X or Y or both X and Y, for example. As a further example, the phrases “X, Y, and / or Z”, “any operable combination of X, Y and Z”, “X, Y, Z or any combination thereof” or “any combination of X, Y and Z” is intended to mean X, Y, Z, X and Y, X and Z, Y and Z, or X, Y and Z.

[0189] It should be noted that terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. These terms of degree may also be construed as including a deviation of the modified term, such as by 1 %, 2%, 5%, 10% or 15%, for example, if this deviation does not negate the meaning of the term it modifies.

[0190] Furthermore, the recitation of numerical ranges by endpoints herein includes all numbers and fractions subsumed within that range (e.g., 1 to 5 includes 1 , 1.5, 2, 2.75, 3, 3.90, 4, and 5). It is also to be understood that all numbers and fractions thereof are presumed to be modified by the term “about” which means a variation of up to a certain amount of the number to which reference is being made if the end result is not significantly changed, such as 1 %, 2%, 5%, 10% or 15%, for example.

[0191] It should be noted that as used herein terms such as proximal and distal of a device or component in the device are defined with respect to the operator (e.g., human or robotic) contact point of the devices described herein. Accordingly, an upper portion of a handle of the device is referred to as a proximal portion of the device while an end portion of the device with a needle that is inserted into a physiological structure is a distal portion of the device.

[0192] In addition, it should be noted that the term distal portion ordistal end portion of a device is meant to cover a region at a distal end of the device and is not limited to the very distal tip of the device. Accordingly, components that are located at the distal end portion of a device does not mean that those components are limited to being located at the very distal tip of the device.

[0193] As noted, while there exists great potential for SCV to improve retinal detachment repair, there are also risks that must be minimized in order for it to be widely adopted. For example, the suprachoroidal space is normally very thin or closed, with the sclera and choroid pressed together. Both layers are very thin, approximately 0.5-1.3 mm and 0.15-0.3 mm respectively [6], [7], Scleral thickness is a key anatomical variable for this type of ocular injection, as the sclera must be precisely penetrated preferably without piercing into or through choroidal tissues, depending on the treatment that is being performed. One of the challenges is that the thickness of the sclera varies based on genetics, age, and region of the eye, meaning the length of conventional needle that is used will not be the same for every patient and also depends on the region of the eye where the needle insertion is to be made. Another challenge is that in the posterior regions of the eye, the choroid is highly vascular. If the needle only partially punctures into the choroid, this may not cause significant issues as a small amount of blood may remain sequestered in the choroid / suprachoroidal space. However, if the needle punctures through the retinal pigment epithelium and into the subretinal space or through the retina, a subretinalhemorrhage or vitreous hemorrhage may occur, increasing risk of recurrent detachment and poor outcomes. Given how thin the choroid is, the margin for error is small. Therefore, an injection device for SCV may preferably be configured to reliably find the suprachoroidal space without overshooting or undershooting, although in some cases, advancing the needle through the choroid to access the subretinal space, may be acceptable depending on the treatment that is being performed.

[0194] An additional problem exists in accessing more posterior regions of the eye (even if still anterior to the equator of the eye) where many retinal tears are located. The orbital bones generally make it difficult to perform this procedure with a straight needle with a direct needle entry. The procedure has currently only been performed in a small range of locations with a makeshift straight needle device, at either the temporal or nasal sides of the eye since these are easily accessible. Suprachoroidal catheters and cannulas have been used to access this space, however, these tools may require an operating room and are rather invasive. In orderforSCV to be adopted, the device that administers the viscous fluid is preferably configured to reach many if not all possible anterior and posterior regions of the posterior segment of the eye in a minimally invasive manner.

[0195] There has been development of devices for SCS access via a needle and delivery of drugs anteriorly. However, there are key differences in requirements that make conventional needles developed for performing various treatments / procedures such as, but not limited to, anterior drug delivery unsuited for posterior macular drug delivery, repair of retinal detachment, and repair of myopic fractional maculopathy, among other ocular conditions and therefore not suitable for applications in which the devices described herein may be used. For example, in anterior SCS drug delivery, injection with conventional devices occurs near the front of the eye, which may require a non-viscous or partially viscous drug in order for it to spread to the target region. However, in SCV, the viscous fluid used to create a localized suprachoroidal buckle is most preferably precisely located under the retinal tear which commonly occurs at the posterior region of the eye. There are fewer risks associated with injections near the front of the eye because the choroid is much less vascular and scleral thickness is somewhat more predictable (approximately 1 mm). Furthermore, if the choroid is damaged in the back of the eye during SCV, bleeding and hemorrhage into the suprachoroidal space, subretinal space, or vitreous may occur. Advantageously, in accordance with the teachings herein there are provided various embodiments of adevice, that may be used for SCV or other fluid delivery or drainage applications, where these devices have a greater level of precision in and control of needle insertion depth to adapt to variations in scleral thickness and ensure the choroid is not punctured (or to ensure more controlled puncture of the choroid if trying to access the subretinal space). Additionally, it is difficult or impossible to access certain posterior injection sites with straight needles since orbital bones prevent a perpendicular approach. In orderforSCV to be able to be used in a wide variety of retinal detachment cases, devices in accordance with the teachings herein, are provided with an actuatable needle for variable depth injection with high control / fine granular control and precision that can minimally invasively inject viscous fluid into the suprachoroidal space in posterior regions of the eye. These same features of at least one of the device embodiments described herein, will facilitate drug delivery to the macula or to any location in the anterior or posterior aspect of the eye and the treatment of myopic fractional maculopathy, among other conditions and applications such as, but not limited to, drainage of certain locations including various ocular locations, for example. While it may be preferable to inject fluid before the needle tip penetrates the choroid, in some circumstances such as drug delivery, the needle tip may be advanced deeper until the user can see it and then pull it back a little and then perform injection. This may be done safely in certain cases and allow for more certainty for the volume of drug delivered.

[0196] Additionally, a desirable feature which is lacking in current needle devices is the ability to sense when the tip of the needle has entered certain ocular locations such as, but not limited to, the suprachoroidal space, for example. The integration of a robust sensing system may make the procedure safer for patients and easier for physicians. In accordance with the teachings herein, one method of sensing when the needle has passed through the sclera is by indirectly sensing a drop in pressure used to inject fluid. Another technique for determining location which is used in optical surgery devices is white light pointed at the sclera from outside the eye which allows the inside of the eye to be viewed through a wide-field lens / microscope or through indirect ophthalmoscopy. By using light for visualization, in accordance with the teachings herein, the optical properties of the sclera and choroid may then be used to determine when the needle tip has passed through the scleral surface and entered the sclera, or other ocular layer, in front of it and when the needle tip has passed through. This may be done using manual sensing, where the surgeon can see a change inintensity or color of light, or via more advanced automated sensing where transmitted or reflected light may be measured and spectrometry tissue identification or thickness measurement methods performed. This may allow for a second sensing method to confirm that the needle is in the correct space before injection in addition to the pressure technique mentioned above.

[0197] In accordance with the teachings herein, there is provided at least one embodiment of an ocular treatment device that is configured to allow a user to precisely control the depth of penetration by using an actuatable injection needle, to sense when the needle has passed into a certain ocular location, such as the suprachoroidal space (SCS), for example, and to inject a treatment fluid (e.g., a viscous fluid during SCV) at that time. At least one of the embodiments of the ocular treatment devices described herein may be used for: (a) treatment of retinal detachment in a minimally invasive manner, (b) treatment of myopic fractional maculopathy with a similar injection of viscous fluid, (c) treatment of conditions using drug injection into the suprachoroidal and subretinal spaces; (d) subretinal drainage, where fluid is aspirated from between the detached retina and Retinal Pigment Epithelium) RPE or suprachoroidal fluid / hemorrhage drainage; and / or (e) any procedure requiring finely controlled (with high granularity) advancement of a needle and sensing of when it has reached a certain target space.

[0198] The various embodiments of the ocular treatment device and associated method of use described herein provide a device which allows a physician to safely probe and manipulate tissue and then precisely extend a needle from the face of the device. The device may be hand-held by a surgeon, for example, or attached to a moveable mechanical mount or a robotic arm for performing a procedure. Once the needle tip has advanced into the correct location within the tissue, medicant or fluid can be dispensed from the device. In at least one embodiment, the device may be used to drain fluid from the target location. In at least one embodiment, one or more mechanisms may be included in the device to sense when the needle tip has reached the target location, without advancing too far (or not at all) past the target location.

[0199] Referring now to FIG. 1 , shown therein is an example embodiment of an ocular treatment device 100 that has an extendable needle 101 at a distal end portion 102 and is configured to reliably navigate the tip of the needle 101 into a certain location, such as the suprachoroidal space (SCS) 103 between the sclera 104 and choroid 105, for example. Once the needle tip 102 is in the SCS 103, an ophthalmicviscoelastic fluid (OVF), ophthalmic viscoelastic device (OVD), or other treatment fluid or substance, is injected which at first creates a suprachoroidal bleb as the OVF accumulates in the SOS under an open retinal tear 201 , as illustrated in FIG. 2. This moves structures of the eye which aid in repair such as allowing the retina 106 to reattach by using the OVF to cause a suprachoroidal indentation / buckle underneath the retina 106 thus functionally closing the retinal tear. The remaining subretinal fluid 202 is absorbed by the retinal pigment epithelium over time, allowing the rest of the retina to reattach. This process is described in United States Non-Provisional Patent Application No. 18 / 770,797 filed on July 12, 2024, and titled “DEVICES AND METHODS FOR POSTERIOR EYE SEGMENT ACCESS WITH ACCURATE LOCALIZATION AND NEEDLE PENETRATION DEPTH”, which is hereby incorporated by reference.

[0200] The shape of the ocular treatment device 100, and alternative embodiments thereof, is configured to be intuitive for the physician to hold as well as conducive to reaching various regions on the eye and various needle insertion depths without causing damage. When injecting into the sclera, the physician applies pressure to the injection site with a lateral surface 1021s of the distal end portion 102 of the device 100 that touches the ocular surface, allowing the location of the distal end potion of the device 100 to be seen from inside the eye with indirect ophthalmoscopy or a microscope. The lateral surface of the distal end portion 102 of the device 100 contacts with the injection site to locally depress the sclera which locally effectively stiffens it and to reduce further tenting of the tissue as the needle advances. The lateral surface 1021s is oriented along a side of a distal end portion 102f of the device 100 (e.g. the lateral surface 1021s is parallel to a longitudinal axis of the distal end portion 102f of the device 100). While this activity is described with respect to device 100, this applies to one or more other embodiments of the device 100 described herein. Most retinal tears occur at the vitreous base or in some cases more posterior such as the equator of the globe and further back, making them difficult to access with conventional, straight needles, as shown in FIG. 3.

[0201] The shape / form factor of the main body 100b of the device 100, where the main body 100b is defined by an outer housing 10Oh, is selected to be generally similar to scleral depressors, which are a common tool in ophthalmology to indent the walls of the eye during retinal examinations. Physicians are comfortable with using devices having a form factor that is similarto a scleral depressor. FIG. 4 shows how a physicianmight indent the eye with the device 100. However, there are some differences in the form factor of the device 100 and that of a scleral depressor in that the distal end potion of the device 100, which has a lateral surface that makes contact with the outer surface of the eye during use, has a radius of curvature that allows the device 100 to more conform with the surface of the globe to reach a desired needle insertion location. Also, the lateral surface 1021s of the distal end portion 102 of the device 100 has a spoon-shape (e.g. concave) which aids in safely distributing pressure across the globe and reaching underneath patients’ eyelids with ease. The lateral surface 1021s may in some embodiments, on the other hand, have a convex portion (e.g., see FIG. 8) in order to provide local indentation pressure to effectively locally stiffen the sclera to aid in needle penetration. Prior to actuation of the needle 101 , the needle 101 is held within the device 100 fully retracted and the lateral surface of the device 100 that will make contact with the outer surface of the eye during use is smooth. This allows the physician to probe and manipulate the eye as well as deliver medicant with the same device.

[0202] The needle 101 extends perpendicularly from the lateral surface 102f of the device 100a in contact with the eye. In an alternative embodiment, the angle / angular orientation that the needle extends from the lateral surface 102f is measured relative to a plane that is tangent to the lateral surface 1021s at the point of needle exit (this point is also known as the needle exit location). This topology allows the physician to reach areas of the eye where a straight needle with direct entry cannot because of the ocular bones, as shown in FIG. 4. The radius of curvature of the distal end portion 102 of the device 100a approximately matches, e.g., to within 20%, the radius of curvature of the human eye, as shown in FIG. 5. The needle 101 may extend approximately perpendicularly from the surface of the distal end portion that 102 lies adjacent the outer surface of the eye during use. The distal end portion 102 may be shaped so that the arc angle can be adjusted to change the length of the curved distal end portion 102 to reach different areas of the eye comfortably, as shown in FIGS. 6A-6C. In at least one embodiment, approximately 15 to approximately 30 degrees was found to be a preferred arc angle for treating retinal detachment. Generally speaking, a small arc angle (e.g. 5 degrees) allows finer resolution of positioning without interference from other biological structures in the region for areas near the equator of the eye, but a larger angle (e.g. 90 degrees) reaches further back in the eye.

[0203] The device may also be implemented in at least one embodiment such that the end portion of the device (i.e., the lateral surface 1021s) to “tilt” away from the outer surface of the eye during use and have a “negative” arc angle; e.g., the longitudinal axis of the distal end portion of the device at a region intersecting with a longitudinal axis of the main body has a negative tilt angle with respect to the longitudinal axis of the main body. For example, FIG. 7A shows a tilt angle which is meant to orient the longitudinal axis of the main body (e.g., mid and handle portion) of the device away from the eye’s ocular axis when the lateral surface distal end portion of the device is placed adjacent the outer surface of the eye to prevent the main body of the device from obstructing the user’s view through the pupil of the eye. For example, in some cases, for some procedures on an anterior portion of the eye, the procedure may be done without any visualization, and in this case the negative arc angle which prevents blocking the user’s view of the patient’s eye or the patient’s view and allows the user or patient to more readily hold the patient’s eye steady. However, this negative tilt configuration may also be more ergonomic so that the shaft of the device does not have to go across the patient’s eye, in which case the patient’s nose may get in the way.

[0204] FIG. 7A shows a negative tilt angle of about 30 degrees for example, compared to the directions shown in FIGS. 6A-6C, while still having a concave lateral surface at the distal end portion with a radius of curvature such that when the lateral surface is in contact with the eye, as shown in FIGS. 7A-7C, the lateral surface 1021s conforms to the curvature of the eye surface in order to inject fluids through the needle 101 into the anterior portions of the eye comfortably. This tilt angle is defined as the angle between the longitudinal axis of the main body (e.g., mid and handle / proximal portion) and a longitudinal axis tangent to the lateral surface at the region it is attached to the main body. However, smaller or larger tilt and / or arc angles (e.g., about -60 to about 60 degrees) may be useful for injecting towards the anterior and posterior regions of the eye. For more posterior locations, a small conjunctival cutdown may be required. An example of defining a tilt 102t is shown in FIG. 7A where the amount of tilt, or tilt angle, is defined between a line 102ax which is approximately parallel with the longitudinal axis of the main body of the device and another line 102at which is approximately parallel to the longitudinal axis of the distal end portion of the device. Thus, in embodiments where this negative tilt angle is employed for the distal end portion of the device for accessing anterior portions of the eye, the curved lateralsurface of the distal portion still has a concave curvature matching the curvature of the eye just like in the other embodiments (for accessing the posterior region of the eye). However, in embodiments with a negative tilt angle, the curved distal portion is tilted backwards from the rest of the device (i.e. the main body I handle) so that the lateral surface of the distal end portion of the device can be positioned on / at the surface of the eye head-on instead of wrapping around toward the back. This allows the surgeon to keep the handle of the device away from the patient’s pupil and the optical lens that the surgeon holds with their other hand to look through the pupil into the patient’s eye.

[0205] Referring now to FIG. 8, as can be seen, in at least one embodiment, such as device 100, for example, there may be a small protrusion, bump or boss 801 on the face of a portion of the distal end portion of the device 100 from which the needle 101 is extended. In such embodiments, the raised surface is at the needle exit location on the lateral surface of the distal end portion of the device so that when a user presses the raised surface against the sclera, a tension is created in a scleral surface to enable the needle to more easily penetrate into the sclera with less pushing away of the sclera. Alternatively, in at least embodiment, such as device 100a, the surface of a portion of the face (e.g., lateral surface) of the distal end portion of the device 100a from which the needle 101 is extended may be approximately flat. Therefore, the protrusion 801 is optional and may not be used for some of the device embodiments described herein. In at least one alternative embodiment, there may more than one protrusion located about the needle exit location.

[0206] It is important for the surgeon to be able to see where the needle 101 will come out any of the devices described herein so that the fluid buckle can be accurately placed underneath the retinal tear or other treatment site. Wide angle viewing microscopes or indirect ophthalmoscopy are used to look through the pupil, allowing for full view of the inside of the eye to localize detachments. The general location of an indentation made by the device on the outside of the eye can be seen inside of the eye. However, the indented area is quite large compared to the needle 101 , so it may be difficult to know exactly where the needle 101 will come out one of the devices described herein. However, the surgeon may be aware of the relative location of the needle exit point, for example on the midpoint of the internal indent of the eye surface. Placing a distinguishing feature at the exit point of the needle tip on the lateral surface of the distal end portion of the device that indents the sclera more than the rest may possibly help localize the injection site. A variety of different geometries for the “bump”801 at the distal end portion of the device where the needle 101 will exit may be used. FIG. 8 shows one possible embodiment with a spherical protrusion as the “bump” 801 (also may be referred to as the “mesa”). Another embodiment may have two or more bumps which may inform the physician of whether the tip is sitting properly tangent to the eye. In various embodiments, light coming out of the tip of the device and / or through the bore of the needle may further help the surgeon place the needle in the correct location. The mechanics of this is discussed later in the description.

[0207] Once needle 101 begins to puncture the sclera, the distal end portion 102 of the devices described herein are preferably held in a steady position. This will prevent accidental damage to the eye and keep the needle depth constant. In embodiments of the devices described herein that are handheld, these devices may include features to make it easier for the physician, a mount or a robotic arm / hand to hold these devices steady. Lines, bumps, or other shapes can be cut or extruded around the body of the devices described herein to improve friction between the external surface of these devices and an object holding the device, such as a surgeon’s hand. For example, referring to FIG. 9, shown therein is an ocular device 900 in accordance with the teachings herein. The device 900 has a main body 901 with a rectangular-shaped section 901a in one portion and a rectangular shaped surface portion 901 b that may improve the grip of a physician holding the device 900.

[0208] The ocular treatment devices described herein also preferably remain stable as the surgeon manipulates controls to extend the needle 101 and inject the fluid. As shown in FIG. 9, the example embodiment of the device 900 utilizes fully mechanical interfaces (e.g., manual input or control interfaces) on the device body 901 which interact with internal mechanisms (e.g., actuation structures - not shown) to allow the surgeon to control the device 900. For example, a needle movement control mechanism may be implemented using a rotational knob 902, rotational dial, or rotational wheel which may be oriented in line with the longitudinal axis of the device body 901 provides continuous needle extension with fine control. The location of the knob 902 near the distal end potion 102 of the device 900 allows the surgeon to control the needle position with one finger and a small amount of travel / movement of the finger. The device 900 also includes a separate slider 903 located more proximally than and spaced apart from the knob 902 which allows for controlling the dispensing of fluid in a smooth motion. In alternative embodiments, other manual inputmechanisms may be used including, but not limited to, mechanical buttons, knobs in different orientations and locations, or other user interfaces, for example.

[0209] In at least one embodiment, the input controls may be motorized in order to require less surgeon / operator manipulation. For example, various degrees of freedom may be provided using electronic buttons, sliders, or a foot pedal. In at least one embodiment, motors may be housed in a separate reusable module and snapped on to the distal or proximal end portions of the ocular treatment device through a mechanical interface (e.g., mechanical linkage).

[0210] Generally, the control inputs used with any of the devices described may be designed in a way that the surgeon does not easily confuse the actuation (e.g., extension / retraction) of the needle 100 with the actuation of fluid injection. Thus, it is preferable that a combination of rotating knobs, sliders, or buttons with distinguishing physical features be used (e.g., different shapes, different textures, different input mechanisms - e.g., a knob is only used for needle extension / retraction while a slider is only used for fluid injection / fluid drainage). It should also be noted that in at least one of the devices described herein, the treatment fluid may come out of the needle 101 as the needle tip transitions between certain structures of the eye before the surgeon uses the control for fluid injection.

[0211] The various embodiments of the ocular devices described herein may employ a wide range of needle tips. Needles with smaller bevel angles are easier to insert into tough tissue, however, such needle tips must be inserted farther to get the bore of the needle into the target space, as illustrated in FIG 10B. This is disadvantageous for the application of SOS injection since the tip of the needle 101 may puncture the choroid before the fluid can even be injected. However, a balance is required between reducing insertion force while reducing the distance the needle tip goes past the sclera before fluid pressure can enter the SOS and push the choroid away. FIGS. 10A-10B compare the penetration depth past the sclera to get the needle bore into the suprachoroidal space for 12-degree and 45-degree bevel needles. Ideally, a needle with as large a bevel angle as possible while maintaining reasonable insertion forces may preferably be used. As an example, the range of angles which may be used for the bevel may range from about 12 degrees to about 45 degrees. A needle with a blunt tip and sharp sides may allow for the needle tip to push away the choroid without puncturing it. Additionally, any of the ocular devices described herein may use a needle with holes on the sides as this may better distribute fluid.

[0212] In another example, FIG. 10C shows a case where needle 101 may enter the ocular surface at an angle. In such cases, at least one of the device embodiments described herein may be modified to inject the needle at an angle such as, but not limited to, about 30 degrees, for example. For instance, allowing the needle tip to enter the sclera at an angle might also be advantageous, as this allows the needle to be deployed having a longer length without passing the choroid and avoids the sharp needle tip directly poking this sensitive tissue. However, entering at an angle may reduce positional accuracy of the injection and carries risk depending on the treatment procedure such as, but not limited to choroidal hemorrhage, when separating the choroid and sclera. Additionally, a perpendicular approach imparts the smallest amount of damage to the sclera. Thus, while the needle approach angle may be varied between about 10 degrees and about 170 degrees, in at least one device embodiment described herein, it may generally be preferable for the needle 101 to extend approximately 90-degrees from the lateral surface of the distal end portion of the device. However, as noted at least one of the devices described herein may be modified to have the needle extend at any angle.

[0213] Rather than concentric sliding, which may be used in conventional needle insertion devices, in at least one embodiment of the devices described in accordance with the teachings herein, such as device 1100 shown in FIGS. 11A-11C, a needle holding member 1102 may be used, with the needle 101 attached at an angle to the distal end portion of the needle holding member 1102 such that the needle may extend from an exit location on a side surface of the distal end portion of the device such that the needle is approximately perpendicularly to this side surface and thereby may enter the eye approximately perpendicularly to the surface of the eye in at least some embodiments. Fluid channel 1103 and light channel 1104 can be integrated into the needle holding member 1102, as shown in FIG. 11 C. The fluid and light channels 1103 and 1104 may run along a majority of the length of the needle holding member 1102 in a side-by-side manner (e.g., approximately parallel to one another) or concentrically. Alternatively, fluid or light pipes may be inserted directly at the distal end portion of the needle holding member 1102, as discussed later in this description. In flexure-based configurations / embodiments, the needle holding member 1102 is made of a material that is semi-flexible such that the needle holding member 1102 can bend with the shape of the body 1101 of the device 1100, allowing for the distal end portion of the needle holding member 1102 to conform to the curvature of the distal end portion 102which in turn preferably conforms to the curvature of the eye for a variety of arc angles as previously explained.

[0214] The needle holding member 1102 may be referred to as a beam. The needle holding member 1102 containing the fluid and light paths may be held and actuated in several ways. For example, referring to FIG. 12, in at least one example embodiment of the ocular devices described herein, the needle holding member 1102 may be attached to a main shaft or a portion of a housing of the device at a proximal end portion P, such that the needle holding member 1102 behaves as a cantilever beam that has a length I and can move a distance dx in the x direction depending on the amount of force applied at the distal end portion of needle holding member 1102. The needle 101 can then be displaced by applying a force at the distal end of the beam 1102. Accordingly, in embodiments employing this pivot-design, such devices have a needle holding member that includes a pivoting mechanism where a position of a proximal end portion of the needle holding member is controlled by the needle movement control mechanism and a pivot point is located adjacent a distal end portion of the needle holding member wherein movement of the proximal end portion of the needle holding member causes the needle to move.

[0215] Referring now to FIG. 13, in another example embodiment, the needle holding member 1102a may be attached at a pivot point PP near the distal end portion of the needle holding member 1102a, such that the member 1102a is in a simply supported arrangement, sliding, or free at a region S near the proximal end portion of the needle holding member 1102a, and driven from a point D in a mid or more proximal region of the needle holding member 1102a. The directions of x and y for the bending axis are shown. A force applied at D resulting in a movement of the beam of AA at point D results in a deflection of dx and angle of 0A below the pivot point PP near the distal end portion of the beam 1102a to move the needle causing it to extend out of the distal end portion of the device. Accordingly, in embodiments which use the pivot design of FIG. 13, such device includes a needle holding member that has a pivot member that is located between the distal and proximal end portions of the needle holding member and supported by a pivot bore in the housing, such that when the proximal end portion of the needle holding member receives a displacing force when the needle movement control mechanism is actuated, the distal end portion of the needle holding member is moved causing the needle to move.

[0216] Referring now to FIG. 14, in another example embodiment, the needle holding member 1102 is configured or arranged to act as a flexure structure, such as a branched flexure structure, in which a displacing force applied near a proximal upper portion of the member 1102b is translated to needle extension at the distal end portion of the needle holding member 1102. For example, in this example embodiment, the needle holding member 1102b is a branched flexure structure with first and second branches 1102b1 and 1102b2 in which a proximal end portion of one branch 1102b1 is coupled to the main body I housing of one of the devices described herein and a proximal end portion of the other branch 1102b2 may be connected to a needle control input mechanism, such as a wheel or knob, where the user interacts with the needle control input mechanism such that an axial force on branch 1102b2 of the member 1102b causes the distal end portion of the needle holding member 1102 to bend, since the other section of the member 1102b1 is fixed in place, so that the needle 101 is extended out of the lateral surface at the distal end portion of the device.

[0217] Accordingly, in embodiments which use the design of FIG. 13, such devices have a needle holding member that is an elastically deformable beam having a proximal end portion and a distal end portion, wherein the proximal end portion is prevented from displacing, and a pivot support is located between the proximal and distal end portions, wherein when an actuating force is applied to the beam between the pivot support and the proximal end portion, the distal end portion is displaced to cause the needle to move through the lateral surface of the distal end portion of the device. In at least one of these embodiments, the elastically deformable beam has a medial portion that extends from the pivot to an actuating force location where the distal end and medial portions are stiffer than the proximal end portion of the needle holding member to reduce deflection of the needle under needle insertion forces, where the deflection due to the needle holding member at the base of the needle is less than 30% of an intended total motion of the needle tip.

[0218] In FIGS. 12-14 and other figures showing embodiments with a pivot point, the pivot point may be accomplished using a pivot member, such as a pin for example, that is supported by a portion of the device such as the housing via a pivot bore in a housing member or housing wall.

[0219] The bending or pivoting of the needle holding members 1102, 1102a, 1102b, shown in FIGS. 12 to 14, which holds the needle 101 may cause the needle 101 to move at a small angle. However, by making the length (I) of the needle holdingmember 1102, 1102a, 1102c long compared to the deflection (dx) needle to extend the needle 101 at a desired amount, this angle can be made small. This is shown as an example in FIG. 12.

[0220] Needle 101 can be advanced precise amounts by applying a force to the distal, middle, or proximal sections of the beams 1102,1102a, 1102b, depending on its implementation, with an actuating member. This may be done using various actuators such as, but not limited to, a wedge, a slot and pin, a rotating cam, a cable system, a pneumatic chamber, or other suitable mechanisms, for example. These actuating members may interface with the input controls (e.g., knob, slider, etc.) directly or through an input linkage system (the “input mechanism") such as, but not limited to, a lever, screw, cam, gear, or other suitable transmission system to transmit human input to motion of a needle. The cam may be provided by an external surface of a member or an internal surface of a member such as a spiral slot, for example. The spatial resolution I fine control granularity of each of these implementations can be tuned in various ways such as, but not limited to, adjusting the pitch of an actuating screw, changing the shape of a slot or cam component, fulcrum location on a lever or adding a gear ratio between the actuation mechanism and an input knob, for example. The geometry of the cantilever or flexure structure may also influence spatial resolution I fine control granularity of the amount (e.g., step size) by which the needle 101 may be extended or retracted. The term “spatial resolution” (also known as “step size”) here refers to how finely a surgeon may manipulate the input mechanism to extend the needle by the step size which is the smallest amount by which the needle 101 may be extended or retracted. Examples of the step size may be from about 0.05 mm to about 0.2 mm. Having a step size with fine resolution advantageously allows the surgeon to advance the needle slowly such that a precise depth may be reached by the tip of the needle 101 when it is inserted into the eye or other tissue. The resolution of the continuous motion mechanism of the cam designs is limited by how carefully the surgeon can move theirfinger and the transmission ratio between the finger movement and the needle movement.

[0221] For example, in at least one embodiment, a cantilever needle holding member 1500 includes a pin 1502 and is coupled with another member 1503 that has a slanted slot 1501 , via pin 1502 slidingly engaging slot 1501 , as shown in the front and side views of FIGS. 15A and 15B. The pin 1502 is at a distal end portion of the needle holding member 1501 and moves vertically and horizontally with an angled slot1501 of actuating member 1503 during which a sideways force is applied to the pin1502 which moves the needle holding member 1500 horizontally. The interaction between slot 1501 and pin 1502 provides bidirectional positional control, allowing movement of the actuating member 1503 to advance and retract needle 101 when slot actuating member 1503 is along the device longitudinal axis direction.

[0222] A view of the slot 1501 shown in FIG. 15C illustrates how the angle and height of the slot 1501 determine the amount that the needle 101 may be extended out of the lateral surface of a device employing this beam and actuation member embodiment. In an alternative embodiment, the shape of the slot 1501 may be altered to change the speed of needle advancement or retraction for certain movements of the slot actuating member 1503 which cause the pin 1502 to engage a portion of the shape of the slot 1501 having a different angle. For example, the shape of the slot 1501 may change along the length of the slot 1501 such that when the shape of the slot 1501 changes to a curve or changes angles along certain sections of the slot and the pin 1502 traverses these sections of the slot, the speed at which the needle 101 advances / retracts is automatically modulated, which may be desirable in order to have the needle 101 quickly reach a certain length then slow down as it gets closer to the target location / target depth for the same amount of user control of the needle actuation control input. Accordingly, the slot has straight segments with different angles that cause the needle to move at a faster or slower rate when the pin moves through the segments. The slot 1501 is able to be placed very close to the attachment point of the needle 101 to the needle holding member 1500, which reduces unsupported beam length at the distal end portion of the needle holding member 1500 increasing stiffness and reducing possible deflection due to needle insertion forces.

[0223] In the needle holding member 1500 embodiment of FIGS. 15A-15C with the cantilever and slot configuration, the slot actuating member 1503 can be moved with a spiral cam 1601 connected or integral with an inner surface of the control knob 902, as illustrated in FIGS. 16A-16C. In various embodiments herein with a wheel having a cam element (e.g., outer surface profile or a slot on at least one side surface) the proximal portion of the needle holding member includes a cam-engagement structure so that when the needle movement control mechanism is actuated, the wheel and the cam rotate and thereby move the proximal end portion of the needle holding member.

[0224] In FIGS. 16A-16C, the ridges 902r of the control knob 902 protrude through a slot in the housing of the device so that the user can move their finger or thumbagainst the ridges 902r to rotate the control knob 902. The proximal end portion 1503p of the slot actuating member 1503 has an upper section 1503p1 with an outer surface that is shaped to slidingly engage an inner sidewall of the main body / housing of a device that incorporates this actuation mechanism of FIGS. 15A-16C and the upper section 1503p1 has a lower surface, that may be referred to as a contact member, that is moveably engaged the outer surface of the cam 1601 , a middle section 1503p2 that is somewhat rectangular and provides a space which can accommodate larger radial sections of the cam 1601 as the cam 1601 is turned and also has an outer curved surface to slidingly engage the inner surface of the housing of the device, and a lower section 1603p3 which is coupled or integrated with the remaining lower portion of the slot actuating member 1503. Since the cam 1601 is coupled to the inner surface of the knob 902 via a pin 1602 and the cam 1601 has a spiral structure in which the radial extent of the lateral edge of the cam 1601 increases in the circumferential direction, as the knob 902 is turned thereby increasing radius of the lateral edge of the cam 1601 that makes contact with and pushes the upper section 1503p1 of the slot actuating member 1503 upwards. This in turn causes the distal end portion of the slot actuating member 1503 to move away from the distal end which causes the pin 1502 on the needle holding member 1500 to move outwards to extend the needle 101 out of the lateral surface of the distal end portion of the device that employs this actuation configuration. When the knob 902 is rotated in the opposite direction the upper section 1503p1 of the slot actuating member 1503 moves towards the distal end since the radial extent of the lateral edge of the cam 1601 decreases as the knob 902 is rotated in the opposite direction. This movement of the slot actuating member 1503 causes the pin 1502 on the needle holding member 1500 to move inwards which causes the needle 101 to be retraced within the housing of the device that incorporates this needle actuation mechanism.

[0225] Accordingly, in such embodiments, the device comprises a slot actuating member 1503 that has an angled slot 1501 at a distal end portion thereof 1102 and the needle holding member has a pin 1502 at the distal end portion that slidably engages the slot 1501 so that when the slot actuating member 1503 is moved, the pin 1502 moves along the slot 1501 causing the distal end portion of the needle holding member to cause the needle 101 to move. Further, the needle movement control mechanism is coupled to a proximal portion of the needle holding member via the camso that rotation of the cam during actuation of the needle movement control mechanism causes the slot actuating member to move.

[0226] Furthermore, in embodiments that use a cam design similar to that shown in FIGS. 16A-16C, such devices comprise a needle movement control mechanism includes a wheel having a cam and the proximal end portion of the needle holding member has a contact member that engages the cam so that when the needle movement control mechanism is actuated, the cam rotates to apply force to the contact member of the proximal end portion of the needle holding member to move the needle holding member.

[0227] One alternative to using a cam to move the slot actuating member 1503 up and down is a screw. A screw may allow for multiple rotations of the control knob 902, whereas a cam will operate with one rotation of the control knob 902. However, a cam can easily be placed in a vertical orientation along with the control knob 902, whereas a screw and nut may have to have intermediary bodies, such as miter gears, so that motion of the control knob creates rotation of a screw oriented along the longitudinal axis of the slot actuating member 1503. A nut in the end of the member 1503 engages the screw thread such that rotation of the screw causes longitudinal motion of the slot actuating member 1503.

[0228] In the elastic beam embodiment of FIG. 13, the force to move the needle 101 is applied to the needle support member 1102a between the pivot point PP and the proximal end support S. A rotating cam 1700, that operates in a somewhat similar to cam 1601 , can be attached to a knob / wheel 902 and used to directly apply force to a needle holding member 1701 , as shown in the example embodiment in FIGS. 17A- 17B. A proximal section 1701 of the needle holding member 1701 is bifurcated to provide a central slot / cutout 1704 (which may be referred to as a cam-engagement structure) that has a cross shape with side-cutouts with surfaces that are moveably engaged by the rotating cam 1700 such that when the knob 902 is rotated the cam1700 also rotates and since the cam 1700 has a non-circular profile, in that certain edges of the perimeter of the cam 1700 have an increasing radial extent from the center of the cam 1700, rotation of the cam 1700 causes the needle holding member1701 to move. The ratio of the perimeters / areas of the larger knob 902a and the smaller cam 1700 affects the control / granularity (e.g., step size) with which a user may extend / retract the needle 101 during use. However, the needle holding member 1701 does not move in a similar manner as needle holding member 1500 since themovement of a portion of the needle holding member 1701 is constrained which causes the needle holding member 1701 to bend when the knob 902 and thus the cam1700 is rotated.

[0229] For instance, in this example embodiment of FIGS. 17A-17B, the needle holding member 1701 has a pin 1703 which interfaces with the main body / housing of one the ocular devices described herein at the distal end portion of the body / housing of the device to create a pivot point about which a distal portion of the needle holding member 1701 may rotate causing the needle tip to translate and penetrate the sclera (e.g. needle holding member acts like a lever). The cross section of the needle holding member should be selected to prevent bending failure. The pivot axis location with respect to the beam neutral axis may be selected to facilitate the manufacturing process used to make the needle holding member. In addition, the needle holding member 1701 has a proximal end portion 1701 p having a shape and outer surface that mates with the inner surface of the body / housing of the device at that portion of the device which also aids to hold the proximal end of the needle holding member1701 in place.

[0230] In this example of an elastic member embodiment, the beam 1701 has an enlarged section 1701e with a cutout 1704 in order for the wheel / knob 802 to pass therethrough. In another embodiment, an example of which is illustrated in FIGS. I SA- ISE, a wheel / knob 1801 may be split into halves 1801a and 1801 b, e.g., two wheels coupled by a pin 1801 p to allow for the pass through of the upper portion 1802a of a needle support member (i.e. , beam 1802) or other components such as a fluid pipe and / or light pipes (both not shown) between the two wheel halves 1801a and 1801 b. The body of cam 1800 is located between the wheel halves 1801a and 1801 b with the pin 1801 p running through the central axis of the cam 1800 and the two wheel halves 1801a and 1801 b, connecting the cam 1800 with the wheel halves 1801 a and 1801b. In this example embodiment, the wheel 1801 is wider than knob / wheel 902, for example. However, the beam 1802 doesn’t need a cutout which a fluid pipe and / or light pipe (which may also be referred to as a fluid channel and light channel respectively) must be routed around. The beam 1802 (e.g., needle holding member) also includes a pin 1803 which serves a similar purpose as was explained for pin 1703. As seen in FIG. 18E, an upper segment of upper beam portion 1802a may have a larger thickness to withstand the forces applied by the cam 1700. In at least one embodiment, it may also be convenient for the cam 1700 to be located on the oppositesurface of the beam 1802 (e.g., opposite the surface of the beam 1802 from which the needle 101 is located. In these cases, an extension to the simply supported member can be made which allows the cam 1700 to pull on the beam 1802 instead of push against the beam 1802.

[0231] Accordingly, in the embodiments of FIGS. 17A-18E, the needle movement control mechanism includes a split wheel having two wheel halves and a cam located therebetween and coupled to the wheel halves, and the proximal portion of the needle holding member is shaped to fit between the wheel halves and be adjacent to the cam so that when the needle movement control mechanism is actuated, the wheel and the cam rotate to move the proximal end portion of the needle holding member.

[0232] In another embodiment with a pivot pin 1703 closer to (e.g., adjacent to) the distal end portion of the device, as shown in FIGS. 19A-19B, the distal end portion of a beam 1901 is attached to the pivot axis member (e.g. pin) 1703 and the proximal end portion of the beam 1901 is constrained by a cam engagement member (e.g. pin) 1904 which movably engages a spiral slot 1902 that is located at a surface of control knob 1801’ having two halves similar to knob 1801. As the knob 1801’ rotates, a distance from the proximal end portion 1901 p of the beam 1901 distance to the longitudinal axis of the device changes with then induces a corresponding displacement of the needle 101 at the distal end portion of the device. Similar to previous embodiments, motion may be realized using a knob similar to knob 902 in which case the beam 1901 has a central cutout as in the case of the beam 1701 shown in FIGS. 17A-17B. In embodiments with such a cutout, the cutout can be covered with material attached to the outer surface of the body (e.g., housing) so that the internal components are not exposed. The two halves of the wheel 180T may be connected by a central portion / member 1903 in between the two vertical halves of the wheel 180T and the member 1903 may be shaped in a way to not interfere with (e.g., not touch) the spiral slot 1902 or directly touch the beam 1901. A mid-segment 1901a of the beam 1901 may be made as wide and thick as possible (e.g., within the confines of the device housing) to maximize stiffness. The size and shape of the beam 1901 is constrained by the outer dimensions of the main body (e.g., device housing), so that as the beam 1901 rotates through the full pivot angle it does not hit the main body / deice housing. A proximal portion 1901 p of the beam 1901 is thinner (has a smaller width) compared to the portion 1901 a in order to fit between the two split knobhalves, however, in another embodiment, it may become wider to wrap around the wheel, as discussed in previous embodiments with a cutout.

[0233] Accordingly, in such designs, the device has a needle movement control mechanism that includes a split wheel having two opposing wheel halves each having a common axis and a spiral cam slot on a side face, the slots facing each other and having a common axis of rotation, the proximal portion of the needle holding member is disposed between the wheel halves and includes a slot engagement member that slidably engages the spiral slots and the main body and when the needle movement control mechanism is actuated, the spiral slots rotate about the common axis and the pin is moved laterally thereby applying a displacing force to the proximal end portion of the needle holding member.

[0234] In another example embodiment that employs a flexural mechanism for the needle holding member, such as flexure embodiment having beam 2001 , shown in FIGS. 20A-20D, two members / branches 2001 a and 2001b connect near a distal end portion of the beam 2001 , with a proximal end portion of branch 2001 b held fixed or pivoting at pivot point 2004 and the other branch 2001 a free at a proximal end portion 2003 of the member 2001 so that the proximal portion 2003 of the member 2001 may move longitudinally when the knob 1801 is rotated. The portion 2003 of the needle holding member 2001 which is free is pulled longitudinally (depending on the direction of rotation of the knob / wheel 1801 in order to cause bending of the branch 2001 b about the pivot 2004 and advance / extend or retract, respectively, the needle 101 depending on the direction of rotation of the knob 1801. A cam 1601 or screw can be used to apply the proximal end displacement, similar to in previously described embodiments.

[0235] One aspect of the cantilevered beam flexure embodiment is that very little upward movement of the free arm is required to fully deploy the needle. This means that needle position may be very sensitive to small movements or bumps of the cam pulling upwards or pushing downwards on the needle holding member. In order to reduce this sensitivity, a lever mechanism may be placed near / adjacent the proximal portion 2003 of the beam branch 2001a. A lever mechanism allows a large displacement on one side of the lever to cause a small displacement on the other side of the lever (e.g., a displacement reduction), and vice-versa. FIGS. 21A-21C show an example embodiment where a lever-like mechanism 2103 may be used to interface between the flexure free end and cam. In this embodiment, a needle holding member2001’ has a pivot 2101 in branch 2001a’ which allows for rotation about this point to cause the desired needle actuation when the cam 1602 exerts a displacement at a proximal end portion of branch 2001a’. In this embodiment, a non-free branch 2102 is fixed rather than pivoting to provide added preload which increases stiffness. Accordingly, in such embodiments using the lever-like design, such devices comprises a wheel having a cam and the proximal end portion of the needle holding member has a lever mechanism having a proximal end that engages the cam such that movement of the cam causes the needle holding mechanism and the needle to move in response.

[0236] The spatial resolution (e.g., step size) by which the needle 101 may be extended or retracted by the surgeon or other operator when controlling the needle length is influenced by the mechanical interfaces described herein. The various devices described herein are implemented so that surgeons are provided with fine enough control to have the needle 101 to stop at a particular / desired location, without going too far through the sclera depending on the type / location of treatment such as the SCS, for example, when treating a retinal tear, which is challenging as the SCS may be only be about a few microns to about tens of microns thick.

[0237] In the cantilever and slot embodiment (an example of which is shown in FIGS. 15A-15D), the slope of the slot 1501 and the diameter of the cam 1601 determine how finely the needle 101 moves (e.g., the spatial resolution) as the surgeon turns the control knob 902. Equations 1 a-1f show how spatial resolution is calculated for the slot and cam embodiment where D is the diameter of the knob 902, Ineedie is the overall length of the needle 101 (not an extended or retracted portion of the needle 101) and A0Cam is the amount of angular rotation of the cam 1601. For example, dimensions of this embodiment, as the surgeon rotates the knob, the needle extends about 0.03 mm for every 1 mm of linear distance knob 902 turns.If Ineedie = 1-3 mm, D = 14 mm, and p = hslot, 0.03 mm (1f)

[0238] For a simply supported beam embodiment, the geometry of the beam determines approximately how much deflection is required at the cam interface for a desired amount of extension / retraction of the needle 100. The equations which determine resolution of deflection for a simple linear elastic beam are shown in Equations 2a-2i. For example, dimensions (shown between equations 2h and 2i) of this particular embodiment, as the surgeon rotates the knob, the needle extends about 0.04 mm for every 1 mm of linear distance the knob turns. These calculations are a starting point to optimize the design for a constant cross section beam. From this, a more complex beam geometry based on finite element analysis methods can be made to optimize spatial resolution and stiffness. In the more complex geometry, the shaft 1702 of the needle holding member 1701 is preferably curved so that it deforms to becomes gradually straighter as the cam 1700 applies force to the needle holding member 1701. This allows for less space in the design, since in the most extended state the movement of the shaft 1702 is limited as the shaft 1702 touches the inside of the outer wall / device housing. However, the beam 1701 may have many different non-linear shapes or may be straight. In equations 2a-2i, F is Force, E is Young’s modulus, I is bending moment of inertia, f = a + b, and a, b and 0A as shown in FIG. 13.diaab(3l+a~)(2e) dOA3l2Needle length ranges from 0 to lneeaie

[0239] It is desirable for the surgeon to have an indication of how far the needle has been deployed. In at least one embodiment, distances can be engraved in the control knob used with the devices herein, an example of which is shown in FIGS. 22A-22C for control knob 2203 with visual distance measures 2203d, to give visual feedback. Accordingly, in such embodiments, the needle movement control mechanism includes visual distance measures to indicate how far the needle tip is advanced when the needle movement control mechanism is actuated. Additionally, in some embodiments, a ratcheting mechanism may be added to the knob in order to provide the surgeon with tactile feedback as to how far the needle 101 has advanced. Accordingly, in at least one embodiment, the needle movement control mechanism includes a ratchet mechanism provided by a rounded or tapered protrusion on the wheel that contacts an extended semi-flexible member attached to the main body which provides resistance to turning the wheel but also yields and allows further movement to provide a user with tactile feedback when actuating the needle movement control mechanism. However, at least one embodiment is described herein where the needle 101 may still be retracted so that it can be safely removed from the eye. In such embodiments, a reversible ratchet 2204 may be used to allow for retraction of the needle. The reversible ratchet 2204 can be used which may be an angled rib or post that extends from the inside surface of the housing 2201 .

[0240] In at least one embodiment, textured bumps 2002 are on the outer circumferential edge of the rotating knob 2203, as shown more clearly in FIG. 22C. Variation in the texture on the outside of the wheel could also be used to allow the surgeon to feel how far extended the needle is, such as a larger bump on the edge of the wheel when the needle is extended 1 mm. In addition, the width of the bumps mayvary from thin to thick, where the thickest bump indicates maximum extension of the needle. Accordingly, in various embodiments, the device may have a needle control mechanism that is a wheel having bumps, slots, depression or other physical indicators around a circumference thereof to provide traction and tactile feel to a user of the device as the user rotates the wheel to actuate the needle. In such embodiments that use bumps or the like, the bumps vary in width and / or circumferential length over a rotation range of the wheel to provide tactile feedback to the user as to a distance the needle is protruding from the lateral surface of the distal end portion of the device.

[0241] In at least one embodiment, the actuation elements of the device are implemented to be sufficiently stiff to prevent deflection under needle insertion forces and beam bending counter forces. The allowable positional error due to external forces is preferably much less than the required spatial resolution (e.g., step size) for needle extension or retraction. Equations 3a-3c may be used to determine the desired stiffness given an acceptable positional error in needle extension / retraction for the embodiment shown in FIGS. 15A-16C, for example. Stiffness can be adjusted by changing the geometry and material of the components. An “error budget” (similar to creating a pareto chart of all the motions in the system that are associated with motion of the needle) can be made so that each component is implemented with a maximum deflection error and such that the total error (Aerror) is under a predetermined allowable / acceptable amount.^needle=needle spatial resolution (step size) ^error=allowable deflection due to external forces Require C.errorrr.neeciieSlot Stiffness: ksiot

[0242] In the embodiment with a slot actuating member 1503, high stiffness can be achieved by making the body of the slot actuating member 1503 concentric with the main body wall (e.g., wall 1101 in FIG. 11 C) so that the slot actuating member 1503contacts the inner surface of the main body wall 1101 of the device housing but is still able to slide (e.g., move up and down) such that there is very little to no deflection of the slot actuating member 1503. An example of this is illustrated in FIGS. 23A-23B. Stiffness for this embodiment then depends on the stiffness around the slot itself and that of the portion of beam between the pin and needle.

[0243] In the embodiments with a simply supported needle holding member (e.g., needle holding member 1701), the primary source of positional error is bending of the beam distal end portion between the pivot point and needle attachment point. Increasing the length (L) of this distal end portion causes the greatest decrease in stiffness, as stiffness is proportional to 1 / L3. Thus, the distance between the needle 101 attachment point on the needle holding member 1701 and the pivot point at pin 1703, may be reduced to increase stiffness. However, decreasing this distance also increases the angle the needle 101 moves through as it extends which may affect the insertion angle of the needle 101 that is inserted into the eye where the insertion angle is preferably about 90 degrees for at least some of the treatments that may be performed using the devices described herein. Accordingly, the value selected for these variables may be balanced based on the maximum allowable insertion angle variation and positional errors.

[0244] Stiffness of a simply supported needle holding member, such as member 1701 , can be increased by varying the cross section of the member 1701. In a first order analysis, stiffness increases most strongly with thickness, T3. However, the distal end portion of the needle holding member is preferably thin in order to keep the device end portion small enough to fit underneath the eyelid during use. However, the cross section can be increased as one moves towards the pivot point to stiffen the distal end portion of the member 1701 while keeping the proximal end portion of the member 1701 thinner than the distal end portion of the member 1701 so as to require less force from the cam 1700 to displace the distal end portion of the member 1701. In such embodiments, the distal end portion of the needle holding member has a greater thickness and is stiffer than a medial portion of the needle holding member. The beam / member 1701 may be made from metal in order to be of the smallest size but have high enough stiffness to retain positional accuracy. A metal beam may be made by forming, printing, die casting or metal injection molding for example. Machining from a solid is also possible but the former methods may likely be lower cost for high volume manufacturing.

[0245] In at least one embodiment, Castigliano’s theorem as well as FEA analysis can be used to analytically select / optimize the shape of the needle holding member 1701. FIGS. 24A-24C show the FEA setup for one possible shape for beam 2401 and FIGS. 24D-24F show the FEA setup for another possible shape for beam 2402. The beam 2401 has a medial portion with a constant cross section and the beam 2402 has a medial portion with a varying cross section with a thicker portion adjacent the distal end portion and a less wide portion adjacent the proximal end portion of the beam 2402 (e.g., the portion adjacent the proximal end portion is narrower than the portion adjacent the distal end portion). Displacement of the needle tip with and without a needle insertion force of 1 N were compared for beams 2401 and 2402. The constant cross section beam 2401 experienced 31 % backwards deflection of the needle 101 due to the 1 N force at the tip of the needle 101 . The beam 2402 with a varying cross section experienced only a 12% deflection while withstanding similar forces and displacement at the cam during actuation. The shape of the beam 2402 may be further optimized and / or certain materials used for manufacturing the beam to yield higher stiffness and smaller deflections.

[0246] Automatic pressurization of the injection fluid as the needle 101 is deployed may be used in at least one of the device embodiments described herein to allow for sensing of physiological layer transitions as the needle tip traverses these different physiological layers by using varying resistances to fluid flow of the different tissues in these physiological layers. Embodiments which employ the automatic pressurization mechanism may also be used for sensing cavities or other potential spaces in a physiological location of the needle tip within the body.

[0247] The collagen structure of the sclera makes it very difficult to inject viscous fluid into it. However, once the tip of the needle 101 enters the SOS, fluid flows more easily. Hence by continuously applying pressure to inject liquid while needle 101 is being extended, fluid will not initially flow as the needle tip passes through the sclera but then as the needle tip first exits the sclera the pressure will push the choroid away from the sclera and the fluid injection resistance drops as the SOS is entered by the needle tip. This may prevent the needle tip from then puncturing the choroid since the extension of the needle 101 may be stopped by the user once the fluid begins to be injected more easily, a bleb forms which the user can see through the pupil of the eye with indirect ophthalmoscopy or a microscope; in other words, a bleb of fluid is formed in the SOS at the needle tip when the injection resistance decreases and the fluid blebmay be visible to the surgeon, signaling that the needle tip is in the correct space (e.g., at the correct depth) so as to stop advancing the needle and the rest of the treatment fluid can be injected This may additionally be applicable for needle injection sensing for other chambers / spaces in the body, such as the epidural space. In at least one embodiment, the needle can be slowly advanced in small increments of, for example, 0.1 mm and then at each increment the surgeon may try to advance the slider to inject the treatment fluid. If the needle is in the sclera the slider will not be moveable as there will be too much resistance to fluid flow. Once the needle tip has been extended sufficiently and it has approached or enters the SCS then the slider will be moveable so that the treatment fluid is able to flow into the SCS. With this technique, as the needle tip gets closer to the SCS, if a light source is provided at the tip of the instrument to pass through the needle, then the generated light will also be able to provide the surgeon cues as to when the needle is close to or in the SCS as described herein.

[0248] In at least one embodiment, automatic pressurization may involve coupling the motion of the actuation elements so that fluid injection pressure is being applied while needle 101 is being extended. In at least one embodiment, such a coupling mechanism may be used to allow the user to apply increased pressure for fluid injection, which may happen when the needle tip is extended to the desired location, for example. A fluid containerfor holding the treatment fluid may be implemented using various components such as, but not limited to, a syringe, an ampoule (e.g., a vial of fluid to be injected), a fluid packet, or a fluid chamber, for example. A plunger may be used to implement fluid actuation. A coupling between the fluid injection and needle actuation components may involve using a mechanical linkage / mechanical interface so that the mechanical movement that deploys the needle simultaneously compresses the fluid container, increasing the fluid injection pressure. For example, the treatment fluid container is coupled to the needle holding member so that movement of the needle holding member to advance the needle also causes an increase in fluid injection pressure. In at least one embodiment, a spring or other elastic element may be placed at this mechanical interface to modulate the amount of injection pressure that is applied. Accordingly, in such embodiments, the treatment fluid container is coupled to the needle holding member via an elastic element that is positioned therebetween and a mechanical element that is moved by a control input. The geometry of the mechanical interface may be selected to control the amount of treatment fluid that is injected during the sudden injection resistance drop when theneedle tip begins to pass through the sclera into the SCS. In embodiments which use electronic control elements, a control signal may be generated by a controller / processor and applied to control the mechanical linkage.

[0249] FIG. 25 illustrates a schematic of a setup for fluid coupling. The coupling can also be arranged in a way that pressure is not applied until the needle tip advances a certain amount in order to prevent accidental fluid injection before the needle tip is in the desired location, such as inside the sclera, which depends on the treatment being performed. The elastic element (e.g., spring) is preferably stiff enough to overcome the friction from the rubber bung and the pressure of the physiological location where the injection will occur, such as the suprachoroidal space for retinal tear / detachment treatment, for example. The elastic element (e.g., spring) also preferably is displaced enough past an equilibrium point such that a significant amount of treatment fluid is automatically injected depending on the treatment being performed, such as during treatment of retinal tear / detachment in which case the automatic injection of treatment fluid will push away the choroid, which informs the physician that the needle tip is at the correct space / location / depth. This can be controlled by changing: (a) the spring constant, (b) the syringe diameter, (c) the actuating component kinematics, (d) the spacing between the top of the actuating element and bottom of the syringe, or any combination of options (a) to (d). Equations 4a-4h show the relationships between the variables involved in options (a) to (d) and shown in FIG. 25 where Asyringe and Aneedie are cross sectional areas. The fluid injection pressure may generally be tuned by adjusting how stiff the elastic element is, e.g., for a spring by adjusting the spring constant. syringe> ^needle / ^spring / Pbung> ^syringe> ^needle Q = Flow Rate, / = Dynamic Viscosity Poiseuille Equation’. P = By(4a)Fluid flows if pressure difference: Pin— Pout> 0 (4b) Pout when needle is in sclera is » Poutwhen needle is in SCSElastic element must apply enough force to make fluid flow.Given a / Sminfrom design geometry, corresponding to the minimum change in lengthThe volume of fluid that will flow into the SCS will be (A — ^min) ^syringe - (4h)

[0250] In the embodiments with the actuating slot member 1503 and embodiments with a double beam flexure 2001 , a proximal section of the slot actuating member 1503 which moves up to deploy / extend the needle 101 , may also be coupled to a fluid container to apply injection pressure at the same time as needle extension. In such embodiments, the needle movement control mechanism is actuatable to cause the needle holding member to move and advance the needle through a needle exit location and to cause fluid delivery of a treatment fluid at the same time through the needle by way of a fluid delivery assembly that is coupled to the needle movement control mechanism. For instance, referring now to an example embodiment shown in FIGS. 26A-26C, a spring 2601 may be located at the upper surface of the proximal section 1503p1 of the slot actuating member 1503 which pushes up on the elastic element 2601 which interfaces with a lower surface of a floating ampoule 2602 that contains a viscoelastic or other treatment fluid. A plunger (not shown) is held in place from above the ampoule 2602. There is also a support member 2603 which is a shoulder or rib that protrudes from the sidewall 1101 of the main body / housing to support the ampoule 2602 so that it does not move downward.

[0251] For embodiments with a simply supported needle holding member, this needle holding member may be configured to also push up on the lower surface of a floating ampoule as the beam / needle holding member is deformed. In such embodiments, the proximal section of the needle holding member is only constrained horizontally by the inner surface of a housing sidewall 901w so that it may slide vertically upwards when force is applied by a cam 1601 during needle deployment. In such embodiments, an example of which is shown in FIG. 27, the elastic element 2601 is located above the upper surface of the proximal end portion of the member 1701 and the lower surface of the ampoule 2602 is above the elastic element 2601 and thesupport member 2603 is included to limit the axial movement of the ampoule 2602 as was done in the embodiment of FIG. 26C. Alternatively, in at least one embodiment, the elastic element 2601 that is typically located between the upper surface of the proximal end portion of the needle holding member body 1701 and the lower surface of the fluid ampoule 2602 may not be used, as shown in FIG. 28. In such embodiments, the upper surface of the proximal end portion of the needle holding member body 1701 may directly abut against the lower surface of the ampoule 2602.

[0252] In device embodiments that use the pivot with a spiral slot (i.e. , a slot that functions as a cam) in a wheel actuated by a user’s finger shown in FIGS 19A-19B, or the flexure with a pivot embodiment shown in FIGS 21A-21C, the needle holding member does not have a portion / section that is above the knob actuating components and so do not simply move to interface with the elastic element without the use of another element. For instance, in the example shown in FIG. 29, the coupling can occur through the control knob 1801 by using a spiral cam or slot 2902 which interfaces with a coupling member 2901 that moves about the pivot 2101 depending on the direction the knob is rotated, to provide coupling between fluid injection and needle extension. An advantage of this layout is that the needle control mechanism and fluid coupling mechanism are separate which may reduce unwanted parasitic forces between them, and they can be independently tuned.

[0253] In another embodiment, movement, which is not purely vertical by the needle actuating elements, may be converted to vertical motion through a slider and crank mechanism in order to apply the coupling force to the fluid during needle actuation. An example embodiment for the slider and crank mechanism is shown in FIGS. 30A-30C. A crank member 3001 has a lower end / l ink that is coupled to a needle actuating mechanism, such as needle holding member 1901 that is coupled to an actuator such as the knob 1801 , and an upper end / link that is coupled to a sliding member 3002 which moves longitudinally within the main housing 901 of the device. For such embodiments having a slider and crank mechanism, as a given needle holding member pivots or flexes during needle extension, lateral movement in the bottom link of the crank member 3001 causes a change in angle which extends the crank member 3001 axially and pushes the sliding member 3002 axially. In at least one embodiment, instead of a crank member with pivots on its two connecting ends / links, the entire crank and slider mechanism may be implemented using oneflexible body that deforms similarly as the crank and sliding members 3001 and 3002 but through using bending (e.g., via flexural joints) rather than rotating joints.

[0254] Accordingly, with embodiments having such spiral slot designs, devices have a needle movement control mechanism that includes a wheel with a central axis of rotation and a spiral slot on a side face and the proximal portion of the needle holding member includes a pin at a proximal end portion thereof where the pin slidably engages the spiral slot and when the needle movement control mechanism is actuated, the spiral slot rotates causing the pin are to move laterally thereby moving the proximal end portion of the needle holding member.

[0255] During use, the surgeon / user is preferably able to dispense as much treatment fluid as needed for the treatment procedure without moving the needle tip once the needle tip is in the correct space. Thus, the mode / mechanism used for combined needle advancement plus automatic pressurization and for fluid injection only is preferably decoupled once the needle tip is in the correct location so that the surgeon is able to dispense a larger amount of treatment fluid relative to what is dispensed when needle advancement is coupled with automatic pressurization. This can be achieved in a variety of different embodiments using screws, cams, or other mechanisms to apply multiple independent forces to the fluid container.

[0256] In at least one of the embodiments described herein, a separate slider 903 may be preferably used to allow the surgeon to inject fluid without moving the needle tip. For example, in at least one embodiment, the slider 903 has a coupling member 903c that is attached or coupled to a portion of a plunger 3101 such as a proximal end of the plunger 3101 , an example of which is shown in FIGS. 31A-31 C. The distal portion of the plunger 3101 is disposed within the ampoule 2602 or makes contact with an upper end of a flexible ampoule so that axial motion of the plunger causes an increase in pressure which will result in the treatment fluid moving through the needle conduit when the injection pressure is larger than a local pressure or resistance at the needle tip when it is inserted within a target location such as a location of the eye. As the slider 903 is moved towards the distal end of the device, treatment fluid 3102 in the ampoule 2602 is dispensed through the needle tip. Markings 3103 along the slider path on the housing of the device may be used to indicate to the surgeon how much fluid has been dispensed / injected in terms of the marking 3103 that the lower end of the slider 903.

[0257] In some cases, the surgeon may want to prime the device to remove air by dispensing fluid through the needle tip before performing a procedure. Thus, in at least one embodiment, a ratcheting mechanism may be disposed along, adjacent or integral with a portion of the slider to keep the fluid container from moving backwards when the elastic element 2601 , which is under tension and located between the ampoule 2602, pushes up on the ampoule 2602 as the needle tip 101 advances. FIGS. 32A- 32B show one example embodiment of a ratchet rack 3201 and a pawl 3202 (e.g., a rib) built into the slider 903 and outer body 801 of the device, respectively. FIGS. 33A- 33B show another version (e.g., alternative embodiment) of a ratchet and pawl mechanism where a ratchet 3201 is on the sides of the slider 903 rather than on a top surface of the slider 903 and the pawl 3202 is disposed at the outer housing of the device and on either side of the rachet 3201 and has a series of inverted teeth.

[0258] In various embodiments described herein, as the elastic element is compressed, forces will be placed on the actuating member which holds the needle position steady. Accordingly, the structural loop between the actuation elements (e.g., the wheel, cam, and actuating body (e.g., the needle holding member and optionally coupled elements such as internal sliding elements, and / or crank members)) is implemented to withstand these forces without deflection. To achieve this, in at least one embodiment, the forces may be directed through the rotational center of the cam. Additionally, in at least one embodiment, at least some of the actuating elements may be implemented with outer surfaces being shaped such that the actuating elements are concentric with the outer body / housing of the device, when possible, to reduce unwanted bending.

[0259] Once the pressure is released as the needle tip enters a desired location with less injection resistance such as the SCS, for example, the floating ampoule will generally move axially away from the support member / hard stop 2603. In at least one embodiment, a clutch 2604 (e.g., see FIG. 26C) that is located in between the hard stop 2603 and the ampoule 2602 can be added to maintain a solid interface so that there is no backlash when a plunger (e.g., plunger 3101) is pushed downwards to dispense treatment fluid. The use of the clutch 2604 also isolates the actuating body from the forces that the plunger 3101 transmits downwards to dispense the treatment fluid. In at least one embodiment, a spring-loaded wedge clutch may be used, an example of which is shown as clutch 2604 in FIG. 26C. Including a clutch mechanism will prevent excess forces on the needle actuating body while dispensing fluid.However, the clutch mechanism will likely have to be reset to have the ampoule 2602 in contact with the hard stop 2603 if the device is to be used in a secondary location so that the spring 2601 still provides automatic pressurization of the fluid. This can be done by adding a release to the clutch 2604 that resets it and the head of the fluid ampoule 2602 to their original positions. The head of the ampoule 2602 is the distal portion of the ampoule that is closest to the needle holding member.

[0260] In at least one embodiment of the devices described herein, an empty drainage chamber may be included which is connected to the needle and allows fluid to be drained from a target physiological location through up the needle into the drainage chamber. The drained fluid may be stored in the drainage chamber. In certain treatments / use case scenarios, intraocular pressure may provide enough of a differential to drive fluid out of the eye when connected to the drainage chamber, such as an empty syringe tube for example, that is kept at atmospheric pressure. This embodiment is shown in FIG. 67.

[0261] For embodiments of the device aimed at drainage rather than injection, fluid and needle extension coupling may not be necessary. However, in at least one embodiment the fluid and needle actuation coupling process may work in reverse, creating a low-pressure cavity in a container, such as an ampoule, so that fluid may be aspirated from a target / desired physiological location as soon as the desired physiological location is reached. This may be achieved by expanding the cavity formed by the ampoule as the needle tip is advanced since this reduces the air pressure within the ampoule because there is the same amount of air but now in a larger space. Many of the actuation mechanisms and fluid couplings previously described may be slightly modified to work in the opposite direction. In such embodiments, the slider may then be pulled upwards to further aspirate fluid or suck up an object from the desired physiological location.

[0262] In at least one embodiment, a device, in accordance with the general teachings herein, may be used to both inject and drain fluid, and in such cases the device includes a treatment fluid container and a separate drainage chamber, and the device may also include a switch mechanism and a three way port with a moveable valve where one port is coupled to the treatment fluid container, another port is coupled to the drainage chamber and the remaining port is coupled to the needle. The switch mechanism may be used to control the valve to move to a first position such that there is an open path between the needle and the treatment fluid chamber for injectingtreatment fluid into the target location in which case the port to the drainage chamber is blocked and a second position such that there is an open path between the needle and the drainage chamber for draining fluid / objects from the target location via the needle tip in which case the port to the treatment fluid container is blocked. In such embodiments selectively controlling fluid flow between the needle and the treatment fluid or draining chambers may be achieved using a mechanical switch that closes one path while opening the other.

[0263] In at least one embodiment, at least one of the devices described herein may further be configured so that a guidance light (e.g., a white or other colored light) is delivered to the general area of the distal end portion of the device such that the light shines in the direction of needle extension and can help the surgeon localize an injection site and / or drainage site as well as visualize a biological element at the target location such as a retinal tear, for example. Alternatively, in at least one embodiment, at least one of the devices described herein may be configured to shine a colored light that may be delivered through the bore of the needle to provide more exact visualization of where the needle tip will come out of the distal end portion of the device. Alternatively, in at least one embodiment, at least one of the devices described herein may be configured to shine both of these lights. In such embodiments, these devices may include light sources, such as LEDs, to shine the white and / or colored lights. Alternatively, in such embodiments, the device may include light paths that are coupled to light sources that are external to the device.

[0264] In embodiments which use a guidance light, choosing a wavelength of light that penetrates within the biological space that is encountered during treatment (e.g., injection and / or drainage at a target location), such as the sclera when treating retinal tears or detachment, may improve the ability for the user to see the needle tip location in patients with a range of scleral thicknesses. The optical properties of the human sclera were investigated by Vogel et al [8], The reflection, transmission, and absorption of different wavelength light may be used in different variations of sensing. For example, longer wavelengths have higher transmission rates while shorter wavelengths tend to reflect. Thus, for example, a light source (e.g., laser or LED), that may generate a red-colored light, may be used to display the location of the needle tip to the user looking inside the eye just before and while needle advancement occurs. Conversely, a green or blue colored light may not shine all the way through the sclera,so using these wavelengths for the guidance light may notify the user only just as soon as the needle tip passes the sclera if the light is delivered through the needle bore.

[0265] In embodiments of the device that shine light (e.g., use guidance light), visible light wavelengths may be used, with red, and green light preferred, although blue light may also be used as it is even less transmissible through certain eye structures and thus will shine brighter once certain eye structures are penetrated such as the sclera for example. These wavelengths may also be more preferable for sensing reflected light and using interferometric strategies to determine what kind of tissue the reflected light bounced off of. In addition, by projecting light around the distal end portion of the device, the needle tip may create a visible shadow that informs the surgeon when the needle tip has passed certain physiological structures, such as the sclera, for example.

[0266] The light can be delivered to the distal end portion of the device using light pipes or optical fibers and light reflection with optional mirrors, prisms, or a photonic crystal at the base of the needle in order to penetrate the eye, or the light generation may be at the distal end portion by placing a light source thereat. For projecting light out the distal end portion of the device, a light pipe can terminate at an inner wall of the distal end portion of the device, where a clear window is placed to allow the light to exit the distal end portion of the device without any attenuation or distortion. For routing light through the needle bore, an optical arrangement may be used that provides alignment between a light source and / or light pipe with the needle bore. For example, light transmitted along the main body of the device through an optical fiber can enter a prism and be turned / re-directed to then enter an opening near the base of the needle that is being inserted into the eye. A mirrored surface or a photonic crystal attached to or part of a component at the end of the needle holding member may also be configured to accomplish this function.

[0267] In at least one embodiment, a light pipe may be directly 3D printed to form the light delivery path 1104 or molded into the needle holding member 1102, as shown in FIG. 11 C. In such embodiments, clear 3D-printed resin may be used to create a light pipe which turns with a small radius of curvature by adding a fluid / air gap around the light path. Materials with high refractive indexes such as Polymethyl Methacrylate (PMMA) may also be extruded to make these light pipes.

[0268] Since there may be inefficiencies in transmitting light around sharp turns through light pipes, it may be more efficient to use a mirror, prism, or photonic crystalin such cases. FIGS. 34A-34B illustrate one example embodiment of an end piece 3401 (e.g., sub-tip assembly) for a needle holding member (e.g., needle holding member 1102 / 1701 / 1901) that terminates the light and fluid paths and couples the light and fluid paths with needle 101 the needle 101 . For example, the fluid path 1104 and the light path 1103 are carried axially through a needle holding member from the proximal end portion of the needle holding member to the distal end portion of the needle holding member. A light beam 3403 may be reflected off of a reflective element such as a 45-degree reflective element 3402 to transmit light along the bore of the needle 101 . This reflective element 3402 may be a mirror or diamond machined piece of copper, aluminum, or other optically reflective material. In alternative embodiments, instead of a reflective mirror surface, a prism may be used to receive light and then transmit the light out at an angle to the input direction (e.g., orthogonal) or a photonic crystal material may be used which bends light at high efficiency. In at least one embodiment, the distal end of the light pipe 1103, which may be an optical fiber, may be cut at an angle to direct the light beam 3403 without needing an optically reflective element.

[0269] In another example embodiment, a light pipe or optical fiber may be inserted directly at the distal end portion of the needle holding member (e.g., needle holding member 1102 / 1701 / 19010) or into the wall / housing 1101 of the device, rather than built into the entire length of the needle holding member. In such embodiments, the light pipe may be inserted opposite the needle 101 or from the side and reflected down the needle bore, examples of which are shown in FIGS. 35A-35B. The fluid may also be carried through a flexible tubing down the length of the wall / housing of the device and inserted at the distal end portion of the needle holding member, rather than running along the entire length of the needle holding member, such that the fluid path (which may also be called a fluid pipe, fluid conduit, fluid pathway, fluid channel) is fluidically coupled to the needle bore.

[0270] In embodiments of the device that use the guidance light, the light generation element I light source may be a laser emitting diode (LED). The light source may be powered by a battery held within the device or through an external power source which plugs into the device. Since a light pipe can be routed through the device, the light source may be positioned at various locations in the device. For example, in at least one embodiment, a small laser diode may be placed adjacent a needle holdingmember and light 3601 can be transmitted along the conduit of the needle 101 , as shown in FIGS. 36A-36B.

[0271] In at least one embodiment, a hollow optical waveguide may be made by polishing or coating the inside of the needle bore with silver or another element. In such cases the reflective coating inside the bore of the needle enables the bore of the needle to function as a light pipe for transmitting light along the needle. In such embodiments, the light and fluid may travel along the same path / conduit and an optical fiber may not be needed. For example, the light can travel by light reflection since the coating of a light pipe or needle internal wall may provide reflection of light.

[0272] In at least one embodiment, the light source may be integrated into a bung / plunger of the fluid ampoule so that a separate manifold to integrate the light path and fluid path may not be needed.

[0273] Referring now to FIGS. 37A-37B, shown therein are perspective and front exploded views of a device 3700 in accordance with the teachings herein. The device 3700 is formed using components from several embodiments described previously for implementing various functions of the device. In this example embodiment, device 3700 uses the components shown in FIGS. 12, 15A-15B, 16A-16C and 26A-26C.

[0274] Referring now to FIGS. 38A-38B, shown therein are perspective and front exploded views of a device 3800 in accordance with the teachings herein. The device 3700 is formed using components from several embodiments described previously for implementing various functions of the device. In this example embodiment, device 3800 uses the flexure configuration of the needle holding member and lever components shown in FIGS. 14, 21A-21 C, and 29A-29B.

[0275] Referring now to FIGS. 39A-39B, shown therein are perspective and front exploded views of a device 3900 in accordance with the teachings herein. The device 3700 is formed using components from several embodiments described previously for implementing various functions of the device. In this example embodiment, device 3700 uses the pivoting beam for the needle holding member and crank and slider components shown in FIGS. 19A-19B and 30A-30C.

[0276] The various devices described herein may be used in a variety of different applications and workflows. Referring now to FIG. 40, shown therein is a flowchart of an example embodiment of one user workflow (e.g., method) 4000 of one of the devices described herein. At step 4002, the surgeon may prime the needle to get rid of any air by dispensing a small amount of fluid from the needle which may involvedriving fluid from the fluid chamber (e.g., ampoule) through the needle. At step 4004, with the needle fully retracted, the surgeon can begin probing the eye with a light (such as the guidance light discussed in some earlier embodiments) in order to find a target location (e.g., an injection site) used for treatment, such as for treating retinal detachment or for drug delivery, for example. At step 4006, once the injection site is located, the needle can be slowly advanced (e.g., extended) by rotating the needle actuation element (e.g., a knob). At step 4008, the needle extends into the sclera. If the device employs a needle extension and fluid delivery coupling mechanism, then at step 4010 fluid pressure is automatically built up by this coupling mechanism and the method 4000 proceeds to step 4012. Otherwise, if no such coupling needle and fluid actuation coupling mechanism is used, the method 4000 proceeds from step 4008 to 4012 where the needle tip enters into the SCS. When the needle tip enters the suprachoroidal space, resistance at the needle tip drops, allowing fluid to flow at step 4014. At step 4018 a bleb forms and the surgeon stops advancing / extending the needle. The operation of steps 4012 and 4018 is visible to the surgeon who is performing step 4016 in parallel through using white light and / or optionally a colored light indication as explained previously. With assurance that the needle is in the correct tissue, at step 4020 the slider can be advanced to inject a desired volume of treatment fluid at the treatment site. While method 4000 has been described with respect to treatment at the suprachoroidal space, treatment can be provided to other physiological locations and / or drainage may be performed using the structures described in various example embodiments herein.

[0277] It should be noted that the various devices described herein may be used for a variety of purposes such as delivery of various types of drugs and also for various indications other than retinal detachment such as, but not limited to, myopic fractional maculopathy. For example, for drug delivery, the device may be used for delivering treatment fluid including medications such as, but not limited to, steroids, antiinflammatory agents, cell therapies, gene therapy, biologics / antibody or antibody fragments, fusion proteins, and other pharmacological agents that may be in a solution, gel / hydrogel or other implantable material that can be injected via one of the devices described herein.

[0278] It should be noted that a surgeon may change the workflow shown in FIG. 40 in various ways. For example, a surgeon may decide that they want to start with a 0.8 or 0.9mm length needle but it may be hard to manipulate the needle to the desiredlocation without puncturing the sclera in undesired locations using conventional devices in which the needle tip is located outside of the device while the device is being moved to the proper location. However, with the various devices described herein, the needle can be fully retracted so that it is within at least flush with the housing of the device so that the distal end portion of the device may be used as a depressor so that the surgeon / user can find the injection location by positioning the distal end portion of the device before the surgeon then extends the needle to a desired length to reach the target location where the surgeon decides the length, such as 0.9mm for example, and then the surgeon may try to use the fluid actuator (e.g., slider) directly to inject the treatment fluid (e.g., viscoelastic). If the slider does not move, this means that the needle tip is in the sclera or other location where the local pressure around the needle tip is larger than the current injection pressure of the device, and then the surgeon can increase the needle extension (e.g., to 0.9 mm) and so on until the slider is positioned so that fluid flows into the target location (e.g., SCS). In other words, the devices described herein may allow the surgeon to first localize the site accurately and then have a needle extend to a specific known length / depth and inject a specific known volume of treatment fluid into a target location such as the SCS, for example. In this case the needle length may be extended to a prespecified amount (but adjustable), and the needle length can be modified during the procedure as required based on how the bleb is forming.

[0279] It should be noted that the various devices described herein may be used for a variety of purposes such as delivery of various types of drugs and also for various indications other than retinal detachment such as, but not limited to, pathological myopia (for prevention of myopic fractional maculopathy, myopic degeneration) and treatment of myopic fractional maculopathy, as well as treatment of reduction of myopia with the procedure addressing some of the refractive error. In these cases, a viscoelastic may be injected in the macular region so that it collects under the fovea. The injected viscoelastic (fluid) may need to be a longer acting substance that may last for about one year or more before breaking down where one example of such a substance is Restylane. The injection into the SCS, during treatment of retinal tears or rhegmatogenous retinal detachment (RRD), may decouple the choroid and retina from the sclera. This may reduce the tendency for the retina to bow back towards the sclera which may promote retinal-choroidal apposition and inhibit structural changes of myopic degeneration and myopic fractional maculopathy.

[0280] Accordingly, provided herein is a method for treatment or prevention of an ocular condition by administering an effective amount of a fluid (for example, a “treatment fluid”) with a device (as described in at least one of the embodiments herein) to an ocular site of a subject in need thereof. Further provided is a use of a device described here for administration of a fluid to an ocular site for treatment or prevention of an ocular condition.

[0281] The term “ocular condition” as used herein refers to both physical ocular conditions such as retinal detachments as well as ocular diseases and ocular injuries.

[0282] As used herein, the expression “treatment of an ocular condition” includes, but is not limited to, reversing, alleviating or inhibiting the progression of the ocular condition or symptoms or conditions associated with the ocular condition.

[0283] Determining an effective amount of treatment fluid to use for treating various ocular conditions can vary according to factors such as the state of the ocular condition, age, sex and / or weight of the subject. In an embodiment, the effective amount is one that following treatment therewith manifests as an improvement in or reduction of any symptom of the ocular condition.

[0284] In at least one embodiment, the treatment fluid is administered once. In another embodiment, the treatment fluid is administered multiple times. For example, the treatment fluid can be administered at least once a day, at least once a week, at least one every two weeks or at least once a month or at least every 3, 6 or 12 months depending on the situation. The length of the treatment period depends on a variety of factors, such as the severity of ocular condition, the age of the subject, the concentration and / or the activity of the treatment fluid (e.g., a therapeutic agent), and any combination thereof. It will also be appreciated that the effective amount of the therapeutic agent used for the treatment may increase or decrease over the course of a particular treatment regime. Changes in dosage may result and become apparent by standard diagnostic assays known in the art. In some instances, chronic administration is required. For example, the treatment fluid is administered to the subject in an amount and for duration sufficient to treat the ocular condition.

[0285] In one embodiment, the ocular site is the suprachoroidal space or the sub- retinal space. In another embodiment, the treatment fluid is a viscous fluid, and the optical condition is retinal detachment or myopic fractional maculopathy.

[0286] In another embodiment, the treatment fluid comprises at least one therapeutic agent or is a therapeutic agent.

[0287] Examples of geometries for different size needles are shown below that may be used in the various device embodiments described herein.Ineedle gauge 0.210 mm^needle 28 gauge 0.184 mm^needle 30 gauge 0.159 mmODfiber= 0.125 mmBore Area28gauge WITH FIBER < Bore Area30gauge NO FIBER< Bore Area27 gaUge WITH FIBERUsing a 27 or 28-gauge needle with a 125-micrometer diameter optical fiber will provide greater than or only slightly less fluid flow area than a standard 30-gauge needle with no fiber. If a 33-gauge needle is used, an optical fiber may occlude too much of the available cross section for fluid flow, and thus it may be preferred for the bore of the needle to act as an optical waveguide and for the light to turn a corner from the source and enter the needle, a prism or photonic crystal may be used.

[0288] As discussed in at least some embodiments herein, fluid delivery and light for illumination, sensing, photo-identification, and phototherapy may be combined in a single device which provides various benefits in many fluid delivery procedures. However, very few current devices offer combined fluid and light delivery, and thosethat do are only designed for a linear approach to the target and / or are bulky, making them unsuitable for less accessible locations.

[0289] Various embodiments will now be described for combining fluid and light paths into a single needle device with a small outer diameter. For example, these embodiments may include a hypodermic or other small needle serving as a photo conduit for light delivery, photo identification, or sensing as well as precise delivery of liquid-based pharmaceuticals or other fluids.

[0290] For example, in at least one embodiment a stepped fluid delivery system for a needle-based device with an optical fiber inside the fluid channel is provided which reduces occlusion of the channel as light and fluid are both delivered to the tip of the needle. In such embodiments, the fluid pipe and the light pipe or the optical fiber are delivered to the needle through a single diameter or a stepped passageway of successively smaller diameters.

[0291] As another example, at least one embodiment is provided in which the bore of a hypodermic or other small needle is treated to have optical properties which allow it to serve as a hollow optical waveguide, particularly at blue-green wavelengths of light.

[0292] As another example, at least one embodiment of needle injection devices is provided for precisely advancing a needle while also being able to deliver fluid and light in an automated way.Needle, Needle Holding Member Design, and Fluid and Light Integration

[0293] Various device embodiments disclosed herein may use a fluid path and other coupling between a fluid ampoule located at, or housed in, the proximal (i.e. handle) end of the device and a needle located toward the distal end portion. FIGS. 41 A-41 E show several views of a device embodiment similar to that shown in FIGS. 19A-19B and in which a fluid path 4103 is incorporated into the needle holding member 1901 , such as by injection molding of the needle holding member 1901 . The distal end of the fluid path 4103 terminates at, and is coupled to, needle 4101 which may be a short and thin needle. The proximal end of the fluid path 4103 may be coupled to another straight or other shaped needle which is used to pierce a rubber end seal (e.g., stopper) of the fluid ampoule (not shown). In other embodiments, as shown, the proximal end of the fluid path may be coupled to a small flexible tube 4102, which is in turn coupled to a needle 4104 for piercing the ampoule seal. This use of a flexibletube 4202, which may be made from polyethylene tubing, for example, can be beneficial when the proximal end of the needle actuating beam is moving horizontally relative to the fluid ampoule, as in the pivoting needle holding beam embodiment shown. In other embodiments (not shown), the proximal end of the fluid path 4103 may be coupled to the fluid ampoule via a rigid or flexible, straight or curved, needle or tube, by means of a Luer lock or other suitable connection. In some embodiments, the fluid ampoule may be a syringe.

[0294] Having the fluid path built into the needle holding member through injection molding, 3D printing, or another manufacturing method allows for tapering of the fluid path in order to increase the overall path diameter and cross sectional area, and thereby significantly decrease the fluid resistance when injecting, since the pressure required to push fluid through a pipe at a certain flow rate is proportional to 1 / D4where D is the inside diameter of the pipe. This is especially important when dispensing high viscosity fluids like viscoelastic fluids for ophthalmology. FIGS. 42A-42C show a device embodiment with a tapered fluid path 4201 that smoothly transitions from the small needle bore size to a larger diameter fluid path. A smooth transition from large to small diameter rather than sharp right angles also significantly reduces the friction factor associated with that part of the fluid path. Additionally, short needles may be attached to the fluid path on each end of the beam 1901 .

[0295] Alternatively, it may be preferable to manufacture a bent needle for the fluid path separately from the needle holding member and then combine the bent needle and the needle holding member. An example is shown in FIGS. 43A-43C of one such continuous bent needle 4301 that may run between the distal and proximal ends of a needle holding member. Transitions from larger to smaller diameters can also be achieved using needle fluid paths by concentrically connecting needles of different diameter, such as shown in FIGS. 43D-43G where the inner diameter of a larger needle 4303 approximately matches the outer diameter of a smaller needle 4304 and they are inserted into each other to form stepped diameter needle 4302. More or fewer needle stages and connections may be useful for different applications. A hole in the side of one of the needles to allow the introduction of an optical fiber into the fluid path is also possible but in other embodiments an optical fiber may be inserted into the fluid path through the open end of a needle along with a mating coupling.

[0296] The needle holding member may have features to allow assembly by securing two or more needle holding member parts around a separate bent (or othershaped) needle. T o provide sufficient mechanical support behind the needle to prevent deflection thereof, the needle may be inserted into the needle holding memberthrough a hole in a proximal end of the needle holding member (e.g., beam) 4401 , as shown in FIGS. 44A-44D, and the bent part of the needle may be held in place by a small snap fit feature 4402 at the distal end / tip of the needle holding member 4401. FIGS. 44E-44F show how the needle may be inserted into the bottom of the needle holding member 1901 and slide through a larger cutout (e.g., channel) 4403 in the needle holding member 1901. Glue or a potting material can be applied afterwards to prevent movement of the needle. For assemblies with larger sized needles mated to the proximal ends, it may be hard to slide the assembly through the bottom of the needle holding member. In this case, a simple slot running along the back of the needle holding member may be used rather than a closed hole.

[0297] The tip (e.g., tip sub-assembly or tip module) of the needle holding member may also be manufactured separately and then attached to the rest of the body of the needle holding member. FIGS. 45A-45C show one such embodiment of tip 4501. In this embodiment, needle 4504 may be fabricated together with the rest of the beam as one part by means of high-resolution 3D printing or micro injection molding. A tapered fluid path 4502 to minimize fluid resistance, as discussed previously, may also be fabricated together. The rest of the needle holding member body may mate with the tip sub-assembly through a press fit 4503 or other connection mechanism. A hole 4505 (e.g., exit location) in the outer body of the needle holding member allows the needle tip to pass through. In these embodiments shown, the outer body tip 4507 is shown separate from the larger device body, however, these may be manufactured as one part or separately. Also, in various embodiments described herein, the tip subassembly may be releasably connectable to a distal end of a lower portion of the main body of the device.

[0298] In an embodiment with the needle tip itself 3D-printed, it may then be structured to enable different tip geometries to be realized. As 3D printing becomes ever better, such as 2 photon printing which can print micron size structures on top of millimeter size Stereolithography (SLA) structures, single piece pivot beam needle 4504 can be made ever more effective at penetrating tissue with lower force. Lower force of insertion may cause less tissue deflection and less deflection of the needle tip itself, making the position of the needle more accurate during injection. The tip canalso be sharpened after printing with a fine stone as a secondary operation after printing or molding.

[0299] A fiber optic cable 3601 , for delivering light to the needle tip through the fluid path, can be integrated into the needle in multiple ways. In the example embodiment shown in FIGS. 46A-46C, a fiber optic cable 3601 may be inserted into the fluid path near where the fluid ampoule is connected by inserting both the fiber optic cable and the fluid ampoule insertion needle 4104 into the larger flexible tube / needle 4102 together. The proximal end of the fiber optic cable may be attached to a laser or LED light source 3701. In other embodiments, the fiber may also be inserted at another point along the path using a small manifold, as shown previously in FIGS. 35A-35B. FIG. 35B shows a small channel 1103 for the optical fiber near the tip of the needle to provide a sturdy place for the fiber.

[0300] Alternatively, rather than having a fiber optic cable pass through the fluid channel to the distal end portion of the device, precise polishing of the needle bore may allow for the needle to act as a hollow metal waveguide. The inside surface may also be coated using chemical vapor deposition to deposit reflective layers. A highly reflective inner surface of the needle effectively makes a hollow center optical cavity.

[0301] As further shown in FIGS. 46A-46B, laser light can be introduced through a clear tube 4102 or clear window on the needle holding beam to reflect into the bore of the needle and transmit around the bend to exit the needle tip. Alternatively, light can be combined with the fluid path with a fiber at the proximal end. Another option is that a laser may be integrated into the plunger of the fluid ampoule, so light is sent directly into the needle bore through the fluid.Preloaded Manual Dispensing for High Viscosity Fluids

[0302] Referring now to FIGS. 47A-47C, to overcome the problem of high forces needed to push the slider 903 forward, a preload behind the slider 903 may be employed. Since the device operator (i.e. a retinal surgeon) may want to prime the needle before injecting treatment fluid (e.g., medicant), meaning they push fluid through the needle to expel any air, the device preloading can also double as needle priming, as some fluid may be lost while pressurizing.

[0303] This functionality can be implemented by moving the spring 2603 that was between the coupling mechanism 2601 and the bottom of the fluid syringe (e.g., ampoule) 2602 in FIG. 27 to the proximal end of the device behind a combined slidingplunger 4705 an example of which is shown in FIGS. 47A-47C. A preload spring 4701 can be loaded to push down on the fluid container / cartridge / ampoule, but in this example a syringe chamber, to overcome the frictional forces in the syringe bung 4706 and apply a force to start pushing the fluid slowly through the needle. The mechanical fluid coupling element 2901 can now push directly on the bottom of the syringe to apply increased pressure as the needle is advanced.

[0304] In the example embodiment illustrated in FIGS. 47A-47C, a lead screw 4703 at the proximal end of the device can be turned by the operator with a knob 4704 to push a spring compressing interface 4702, which is under the screw 4703, towards the spring 4701 which in turn applies more force against the sliding plunger 4705. Compression of the spring 4701 and preloading of the syringe may be achieved using other mechanisms as well, such as by pressing a rear plunger with a ratcheting mechanism against the spring.Motorized Device

[0305] Some embodiments of the devices described herein may have electric motor(s) to dispense the fluid and / or actuate the needle. Motors allow for much lower input forces and lengths of movement from the surgeon to use the device.

[0306] In some embodiments, only the fluid dispensing is augmented with a motor 4801 , as shown in FIGS. 48A-48D and FIGS. 49A-49C. The distal end of the device which controls needle actuation is the same as the pivoting embodiment, shown in FIG 47C; however, here a linear actuating motor 4801 moves member 4802 that pushes the fluid plunger 4803 which pushes on the bung 4706 inside the ampoule of fluid to cause the fluid to move through the needle when power is provided to the motor.

[0307] The embodiment in FIGS 48A-48D uses an electronic button momentary switch 4804 to actuate the motor 4801 that pushes the fluid through the needle. The embodiment in FIG 49A-49C uses a slider 4901 , which when pushed activates the motor.

[0308] In some embodiments the device may be structured such that it can separate into two sections, as shown in FIGS. 50A-50C and FIGS. 51A-51 E. A proximal section 5001 / 5101 (also referred to as a proximal half, upper half / section or handle half / section) may contain the electronic components and be designed to be sterilizable and reusable. The distal section 5002 / 5102 (also referred to as a distalhalf, lower half / section, tip half / section) may hold the needle and be disposed of (e.g., discarded) after each procedure. Accordingly, the proximal section 5001 / 5101 can then be connected to a different distal section 5002 / 5102 and used again.

[0309] The section with electronics may house a battery 4811 , a microcontroller 4812, a motor 4801 , a light / laser source 4810, button 4804 to actuate the motor 4801 , and any other sensors.

[0310] For the embodiment in FIGS. 50A-50C, the split / separation is made along a jagged cut line (e.g., a zigzag or piece-wise line) and the two sections can be connected by linearly pushing them together. These sections may be secured with any suitable locking feature such as a releasable tongue and groove connections to releasable snap fit connections, for example. The purpose of this cut line shape is to get the electric button 4804 to be physically close to the control knob 1801 to make it easy for the operator to reach both the button 4804 and the knob 1801 with minimal finger movement. In the embodiment in FIGS. 51A-51 E, the slider 4901 allows the button and wires to be placed in the proximal end of the device 5101 with the electronics, simplifying the cut line of the device to a straight line. The two sections may be connected with a Luer lock 5103, screw thread, snap-fit or other such mechanical interface to create a releasably secure connection.

[0311] In order to achieve coupling between the wheel movement (e.g., needle actuation) and pressurization of the fluid, a sensing mechanism, such as a hall effect sensor 4809 and a magnet 4814 located in the wheel 1801 (shown in FIGS. 48A-48D) can be used to sense when the wheel / knob 1801 is moving. An electronic circuit with or without a microcontroller can then send signals to the motor 4081 to move member 4802 to pressurize the fluid. An alternative sensor, such as an encoder, e.g., an optical or a magnetic encoder, may be used in other embodiments, to directly sense motor rotation speed which may be used to indicate motor effort (e.g., the coupling force) which corresponds to fluid pressure and motor speed which corresponds to fluid flow rate. An alternative to an encoder is to sense voltage and current at the electrical lines that lead from the controller to the motor. The controller will output a desired voltage to the motor, but as the motor spins, back EMF is generated that causes a fluctuation in the voltage. This can be sensed and fed back into the controller to interpret motor velocity. In addition, current can be sensed to interpret torque the motor is exerting and hence fluid pressure. The sensor(s) can be a sensing circuit whose voltage is digitized by an analog to digital converter and read by the controller which thengenerates an output signal for a transducer (e.g., a speaker or a light source), or the sensor(s) output can be directly processed (e.g., amplified) and transduced by the output device to provide a signal such as sound or light to the user, for example. Accordingly, in at least one embodiment herein, the device comprises a motor for actuating fluid delivery, a sensor for sensing a change in magnitude of current drawn by the motor due to changing torque based on fluid flow, and a sensor for sensing a change in frequency of the current drawn by the motor due to back Electromotive Force (EMF) due to change in motor speed due to changing fluid pressure and a controller for receiving sensor signals indicating any changes in the magnitude and frequency of the current drawn by the motor.

[0312] Referring now to FIG. 69, shown therein is measured current and voltage for a motor that controls a plunger for fluid injection with a force. Current data was measured applying a constant force of 20 N to resist movement of the plunger by the motor and is shown as the top curve from the first channel of the oscilloscope screenshot in FIG. 69. Four magnets attached to the motor shaft trigger two offset stationary hall sensor four times per revolution, as shown in channels 2 and 3 of the oscilloscope readout. It can be seen from the current readout in channel 1 that six clear spikes in current occur per revolution due to changes in the back EMF as the DC motor commutator changes position with respect to the stationary windings.

[0313] Alternatively, another embodiment, which allows the operator to manually turn on and off the fluid flow, may include an on / off switch in close proximity to the needle control knob. This on / off switch may be pressed to initiate low flow rate dispensing of the fluid or force control of the motor plunger against the fluid to pressurize the fluid by a given amount. In this embodiment, there is no dependence on sensing to initiate coupling of the fluid with the needle movement, as it may be in control of the operator by depressing the on / off switch.

[0314] In at least one embodiment, there may be separate buttons I switches to turn on fluid coupling and fluid injection, or the same button may be used to do these functions. It may be desirable for the fluid coupling to operate at a lower pressure than full injection or vice versa in certain cases.

[0315] In some embodiments, a power switch 4813 on the back of the device may be used to allow power to be turned on or off.

[0316] Alternatively, or in addition to the power switch 4813, in some embodiments, a reset button may be included to retract the motor plunger.

[0317] In other embodiments, it may be desired to motorize both fluid delivery and needle advancement. This can be done with an embodiment similar to the slot embodiment in FIGS. 15A-15D. As shown in FIGS. 52A-52B, the pin 5201 at the proximal end of the needle holding beam 1901 , which usually is positioned by the control knob slot 1902, is instead controlled by a slot 5203 in a body 5202 pulled linearly upward by another motor. The resolution of motion in this embodiment can be made very fine by adjusting the slope of the slot and the motor linear movement resolution.

[0318] The force applied by the motor to the syringe plunger may be used to control dispensing fluid thereby correlating fluid pressure with needle advancement. Motor force may be controlled by adjusting the amount of current applied to the motor and correlating this to motor output torque and applied linear force through the motor torque constant.

[0319] However, in other embodiments, position control may also be employed to ensure a designated / predetermined / desired volume of fluid is dispensed. However, it may be hard to reliably use only position control for the fluid flow since if fluid is ejected before the needle is in the desired position in a target organ such as the SOS of the eye, the motor controller may not be able to sense this loss of fluid. Thus, in at least one embodiment a combined position and force sensing scheme may be employed where force sensing is used to determine when the needle tip just penetrates the sclera and position control is used for dispensing.

[0320] In one embodiment, a foot pedal may be used to control the motor so the user can simultaneously control the needle and motor and thereby remove the need for control switches on the handheld device. In some embodiments, the foot pedal may use a potentiometer or other mechanism so that power to the motor can correspondingly be increased as the foot pedal is depressed further. A circuit to sense motor current draw and back EMF frequency can be used to provide signals that can be processed (e.g., amplified) and presented as an alert or indication to the user of the effective pressure and flow rate. For example, a controller may be adapted to provide alerts corresponding to changes in fluid flow and fluid pressure based on the measured changes of the magnitude and the frequency of current drawn by the motor, respectively. In at least one embodiment, the foot pedal may also allow for yaw motion of the foot to activate the light source. In such embodiments, pitch motion of the user’s foot activates the motor and yaw motion of the user’s foot activates the light source.Accordingly, for motor control of needle actuation, high resolution position control may be achieved.

[0321] FIG. 53A shows an example of the control inputs and outputs of the whole device and FIGS. 53B-53C show two example embodiments of electronics using analog or digital control. A flow diagram mapping control inputs to outputs is shown in FIG. 53A. As described below in other embodiments herein a foot pedal is used, the control electronics may be housed with the foot pedal and the handheld system further simplified to, rather than use the hall effect sensor and magnet, instead rely on the user receiving signals about the pressure (related to motor current) and flow (related to motor speed as determined by back EMF frequency) to actuate the foot pedal to produce the flow of fluid through the needle the user desires.

[0322] A control scheme without a microcontroller is possible, as shown in FIG. 53B. The basis of this method uses Hall effect switches to turn on or turn off the motor 4801. When the control knob 1801 moves forward, the magnet position triggers the Hall-effect switch to be closed, leading also to closing of switches in an H-bridge based DC motor controller or relay, which allows current to flow to motor 4801 . The coupling force applied by the motor 4801 is pre-set by controlling the amount of current which flows to the motor 4801 . This can be done by adjusting the supply voltage or adding a dissipative resistor into the path. A separate fluid dispensing button 4804 also closes the H-bridge or relay and moves the motor forward. If it is desired for the coupling and dispensing to operate at different pressures, two separate H-bridges may be used, one with a buck converter before the H-bridge motor voltage input. The motor 4801 may also have built in limit switches which turn it off when it fully dispenses fluid. This analog control scheme is advantageous for simple on-off control as the components can fit in a small space and no software is required.

[0323] A microcontroller may also be used to send pulse-width modulated signals through the motor controller to control force and speed of the plunger movement more precisely. This electronic scheme is shown in FIG. 53C.

[0324] In some embodiments, a force sensor may be included in line with the plunger to create a closed-loop control scheme where the actual output force is considered when supplying the motor 4801 with voltage through the microcontroller.

[0325] In another embodiment in order to minimize complexity and provide acceptable / “good enough” sensing of when the needle tip first penetrates the sclera, the fluid control mechanism’s electrically powered motor actuated extendablemember, uses a DC motor where the user actuates the control mechanism, such as with a foot pedal, to apply voltage to the motor to cause the fluid to flow from the vial through the needle. The control mechanism electronics senses the motor current changing in accordance with the motor torque creating the force to dispense fluid from the vial. The force needed to dispense fluid causes the current draw magnitude to change, and the frequency of the current draw changes due to back EMF-effect on the motor windings that corresponds to the motor’s rotation speed, with the result being that the flow rate and pressure of fluid dispensing can be inferred by the controller by measuring these effects and used to inform the user by sounds, lights and / or tactile feedback as to the progress of the needle through tissue. For example, a) a high current draw and low frequency implies fluid is not flowing and the needle has not penetrated yet through the sclera while b) a sudden drop in current and increase in frequency indicates the fluid has started to flow because the needle tip has penetrated the sclera, and the user should stop advancing the needle. The sensing and display may be achieved entirely using analog electronic components so as to not require software and thereby maximize reliability and minimize regulatory approval time, or it may be done digitally where software enables more customization and the including of data acquisition and transmittal to a central repository to enable artificial Intelligence to learn with each use of a device how to better control devices and better display to user the state of use. This type of sensing is referred to herein as “motor impedance sensing”.Suction at the Tip

[0326] In some embodiments it may be useful to have suction around the needle at the distal end portion of the device to pull the outer surface of the eye or skin (or other physiological surface) towards the surface of the device that is adjacent to the face so that the physiological surface remains stationary against the device surface and does not indent when the physiological surface is being punctured with the needle. This helps to ensure accuracy and repeatability in the needle penetration depth. This is further described in some following embodiments.

[0327] As shown in FIGS. 54A-54B and FIGS. 55A-55B, an open region 4505 at the end of the body 4507 of the illustrated tip sub-assembly, which is partially occluded by the needle 4504, will pull the target physiological surface against the device when a negative (vacuum) pressure is generated at the open region. When the pivot beam,or other actuating member, is activated to extend the needle and penetrate the physiological surface, the physiological surface (or entire object) will then be less likely to locally be pushed away by the needle prior to penetration and then to snap back once penetration starts, which is advantageous since both of these effects may lead to over-penetration of the needle (e.g., the needle insertion depth being too much). This is referred to herein as “snap-through penetration”. For the sclera of an eye, mitigating this effect reduces the chance of accidentally penetrating the choroid when trying to position the needle tip in the SCS.

[0328] FIGS. 54A-54B and 55A-55B show an instrument tip element 5401 similar to modular pivot element 4501 (in FIGS. 45A-45C) with fiber optic 5501 and vacuum passages 5402. This is similar to the modular tip (also referred to as a tip subassembly) shown in FIG. 45A-45C with needle tip 4504. Pivot beam tip 4501 has an end bore 4506 that is larger than bore 4502 such that when a rigid hollow tube is inserted and attached to tube 4503, such as by bonding, it may act as lever arm and function similar to needle positioning beam 1901 in FIGS. 44A-44D, and the bore 4502 of the tube 4503 may then be in line with flexible member 4102.

[0329] The fiber optic passage 5501 is in boss structure 5502 and is a straight hole projecting forward that exits into the needle bore 4502. A fiber optic cable 4807 may have its center optical fiber 4806 without its outer jacket slid through passage 5501 and extend to near the top of the needle 4504.

[0330] The vacuum passage 5402 may mate with a similar passage to be included in body of the instrument. The vacuum passage 5402 may be coupled in a medical office to a vacuum source which is commonly available for suction. The vacuum passage exits inside the body of the device at aperture 5503. A seal 5601 , shown in FIG. 56 (not shown inserted in FIGS. 54A-54B and 55A-55B) may be provided in the form of a non-porous soft resilient member (e.g., closed cell urethane foam with mating contour 5602 to the inside of the end of the device at 5504, where the seal may have an adhesive on one side to adhere it to the bulkhead 4507) with a center hole 5603 to accommodate the cross section of the pivot beam 4503. As a resilient porous member with the center hole 5603 of a diameter smaller than the end of the pivot beam 4503 the vacuum seal will still be maintained well enough, and the pivot beam can still pivot while the application of a vacuum pulls the seal against the bulkhead. Pressures on the order of 1 atm of vacuum applied to the region 4505 when the tip of the instrument is pressed against the object to be penetrated, such as an eye, are sufficient to mitigateindentation. Table 1 shows the force the vacuum applies on the eye or skin based on vacuum pressure and area.Table 1 : Force applied to injection object based on vacuum pressure and area of applied vacuum

[0331] The penetration force for a 28-gauge needle may be on the order of about 0.5 N and the applied vacuum can help prevent the object to be penetrated from being deflected away from the tip, thereby reducing the potential for snap-through penetration.Light Activated Hydrogel

[0332] The liquid that is injected to create a suprachoroidal buckle and force the choroid and retinal pigment epithelium to come in contact with the retina may be a hyaluronic acid. In addition, with the ability for the current embodiment to deliver laser light through the needle tip, a photosensitive liquid may be used where the viscosity increases with application of laser light to create a fluid state that takes longer for the eye to absorb, and hence a slower return of the choroid to the sclera which gives more time for the retina to heal and reattach.Force Feedback

[0333] It may be valuable for surgeons to be able to sense the forces they are applying to the tissues of a patient with an intermediary medical device. Specifically, for suprachoroidal delivery of medicant, it is important for the surgeon to be able to sense the forces required to inject fluid, since this informs whether or not the surgeon is in the SCS or the needle is still in the sclera. This may be achieved, for example, as described above by in the motorized fluid dispensing embodiment sensing a fluid dispensing motor current magnitude and frequency and displaying the results to the user.

[0334] Force feedback integrated in the fluid actuating button embodiment where force information is provided to the surgeon by changing how hard the button or slideris to press or move. This may be done with another small motor or actuator inside the button or slider.

[0335] Alternatively, a spring which controls how hard it is to push the button may be compressed as the motor pushes on the plunger, making it more difficult to press the button and actuate the fluid, as shown in FIG. 57. This may be a mechanical way to give force feedback. This may still make the required actuation forces much smaller than might be required without a motor, but the input forces from the surgeon may change to indicate injection force.

[0336] In another aspect, in at least one embodiment, at least one of the devices described herein may be structured so that it has at least two modules: 1 ) a tip subassembly, and 2) a device body. The tip sub-assembly can be considered a disposable element; whereas the body of the device can be reusable and can house consumable fluids. This may result in various advantages such as increased useability and reduction of waste as the device body may be reused while the tip sub-assembly may be replaced.

[0337] Referring now to FIG. 58A, shown therein is a cross section of an eye 10 with a retinal detachment and a cross-sectional view of a tip sub-assembly 5810 that may be used with one of the devices described herein prior to the insertion of the needle tip 58211 (shown in FIG. 59B) into the eye 10.

[0338] The tip sub-assembly 5810 can include at least two or more components. The two primary components are a tip housing 5820, which serves as a mounting structure for a needle member 5821 . The anterior concave inner surface 5820s of the tip housing 5820 has the needle aperture 5820a which is the exit location of the needle tip when it is extended outside of the housing 5820. The needle aperture 5820a may have a pocket recess 5820p to align and hold an interface gasket 5825 (e.g., see FIG. 58C). Alternatively, the interface gasket 5825 can be adhered to an anterior concave inner surface and aligned using the needle aperture 5820a. The posterior connection region 5820c of the tip housing 5820 can include alignment features 5820k (see FIG. 58C) such as partial spheres or v grooves integrated into the body. The alignment features 5820k, can be used to align the tip sub-assembly 5820 to a distal portion of the body of the device. FIG. 58C is an exploded view of the tip sub-assembly 5810. The needle member 5821 may be assembled to couple with the housing 5820 using various techniques such as via a rotational mate between a housing axle pocket 5820r and the needle axle 5821a. The illustrated embodiment allows for approximately atwelve-degree rotation between the housing 5820 and the needle member 5821. In other embodiments, other degrees of rotation may be used.

[0339] The tip sub-assembly 5820 has the ability to be pressurized (e.g. pull vacuum) inside the housing interior chamber 5820L In the sealed state, the tip subassembly 5820, has the needle aperture 20a with a seal 5825 and at least one vacuum port 5820v in the tip housing 5820. The vacuum port 5820v provides a route to the housing interior chamber 5280i. A second vacuum port 5820v may be used to regulate the pressure inside the housing interior chamber 5820i (e.g., see FIG. 58B). The posterior connection region 5820c has essentially a bulkhead 5820b region that is sealed while still allowing the rotational motion between the tip housing 5820 and the needle member 5821 . Sealing at the bulkhead 5820b can be created using a flexible sealing layer 5812 (e.g. flexible closed foam tape) in FIG. 58C, in conjunction with a seal cap 5813 which may be approximately 350 pm in thickness in at least one embodiment. The function of the seal cap 5813 is to maintain a seal despite the rotational motion of the needle member 5821a relative to the axle pocket 5820r. The sealing layer 5812 can conform to the interior wall of the housing bulkhead 5820b region, the anterior face of seal cap 5813 and the exterior surface of the needle bore housing 5821 b around the needle bore (e.g., see FIGS. 58B and 58C for tip subassembly 5810). During the assembly process, the sealing layer 5812is made to conform to the aforementioned structural features by temporarily closing both the needle aperture 5820a and needle bore aperture and pulling a vacuum inside the housing interior chamber 5820i using the vacuum port 5820v. The differential pressure pushes on the flexible sealing layer 5812.

[0340] Different types of materials may be used for providing the seal. For example, it was demonstrated experimentally that a 3M flexible closed foam tape can be used to provide sealing either by being sandwiched between the housing 5820 and the seal cap 5812 or on top of the seal cap 5813. Depending on the embodiment, the bulkhead sealing layer may also include a light coat of flexible quick drying material (e.g., a liquid bandage). There are also several different alternative methods that may be used for sealing the bulkhead. For example, a thin flexible material (e.g., a 3M Nexcare tegaderm) may be used in conjunction with vacuum chuck fixtures to handle and transfer the thin membrane (e.g., ~ 40um thick).

[0341] Other considerations for implementing the bulkhead seal may include manufacturing and scalability. At the prototype stage, the seal cap 5813 may be placedon top of a double sided flexible closed foam tape 5812. The seal cap 5813 may then be pressed onto tape and material may be trimmed / removed using a precision blade. The cross-sectional section that remains after this trimming step is preferably similar to the bulkhead area. In production, the cutting of the bulkhead shape may be done using a die cutter. For the embodiment illustrated in FIG. 58C, a circular aperture may be created in the sealing layer 5812by using a biopsy punch. The size of the circular aperture may be slightly smaller than the exterior surface of the needle bore housing 5821 b (e.g., also referred to as needle bore housing). For example, when the needle bore housing 5821 b outer diameter is ~2.5 mm then a biopsy punch of 2.0 mm in size may be used. The overlap region of the sealing layer 5812and the wall of the needle bore housing 5821b helps to provide a good vacuum seal.

[0342] The tip sub-assembly 5820 is structured to align to the body of the probe / device and to also be securely held in place when installed. The alignment may be performed via the alignment features 5820k of the housing 5820 of the tip subassembly 5810. The tip sub-assembly 5810 may be releasably coupled to the body of the device via a kinematic coupling I kinematic interface an example of which is illustrated in FIG. 58B. One of several means may be used to secure the tip subassembly 5810 to the body of the device which include but are not limited to: a mechanical latch (e.g. snap fits / flexures), fasteners, magnetic elements, friction fits, interference fits, and the like, for example. For example, one method to secure the tip sub-assembly to the body of the device may be to use two fasteners 5822 such as for tip sub-assembly. In such cases, the tip housing 5820 may include two fastener flanges 5820f with clearance holes (not shown).

[0343] The structure of the needle member 5821 may be implemented to take into account manufacturing, fluidic resistance, and / or functionality considerations. The fabrication of the needle member 5821 can be either monolithic using 3D printed technology or assembled using telescoping bent needle tubing, for example. The benefits of using 3D printed technology can include the ability to generate a smooth transition of the needle cross section, eliminate tolerance stack up in conventional assemblies, and implement complex features which is possible with existing commercial ultra-high printing resolution which is on the order of 2 urn with a printing tolerance of + / - 5um. The tip of a 3D printed needle member can be post processed to further sharpen cutting edges. Conventional naming nomenclatures are used to identify the needle member tip 5820t, lumen 5820i, and cannula 5821c for thedescription herein and corresponding figures. Fluidic considerations suggest that the needle lumen 5821 i (e.g., fluid path 5402) be as large possible to reduce fluidic resistance; however, this may be balanced with a decrease in the effective cannula 5821c diameter which is preferable to reduce injection size. For ocular surgery, needle gauges between 27 - 30 are standard (e.g., typically used).

[0344] The needle tip 58211 can be configured according to an array of various geometries in which the needle tip height 5821 h (shown in FIG. 59B) is preferably as shallow as possible, so as to allow the lumen fluid plane 5821 f to introduce fluid into an ocular region, such as the SCS 5804 for example, without the tip engagement 5821e unintentionally piercing an ocular structure such as the choroid 5806, for example. Off the shelf needles having 27 and 30-gauge tip geometries were measured to have distances from tip engagement to lumen fluid plane at ~1 .47 mm (27 gauge - OD 413 urn), and ~1 .0 mm (30 gauge - 312 urn OD) respectively. Therefore, the ratio of needle diameter to depth lumen closure to tip is approximately three. Since the minimum thickness of the sclera 5802 is on the order of minimum thickness of 400 urn, the distance from the tip engagement to the lumen fluid plane 5821f may be selected to be less than 350 pm. Accordingly, when the tip engagement 5821 e just pierces the inner wall of the sclera 5802, the lumen fluid plane 5821f is completely inside the sclera 5802 thickness.

[0345] As shown in FIGS. 59A-59G, the needle tip 58211 may have an arched piercing region 5821 p (e.g., such as with a biopsy needle), multiple piercing points of contact 5821 p2, an asymmetric design 5821 p3, or combinations thereof. As mentioned earlier accessing regions near the back of the eye 10 can be quite challenging. Accordingly, experiments were performed where seven needle member prototypes were fabricated and tested to determine the relative insertion force. It was determined experimentally that one of the needle embodiments with the lowest insertion force is a coned tapered tip similar to a biopsy punch with an additional crowning 5821 n at the tip 58211 as shown in FIG. 59G for example. The structural aspects of the embodiments were selected to create a slicing motion as the needle tip 5821t travels in an arched or curved path. However, during testing, after initial contact, the needle member 5821 of FIG. 59G continued to rotate in the arched path which created more of a rolling slicing motion along the arch to penetrate, whereas an axial needle creates a piercing pushing motion. The needle tip 58211 may include a taperedsection 5821m (e.g., FIG. 59E, 59F, 59G) or chamfers 5821 r (e.g., FIG. 59D) to create a cutting edge or piercing points 5821 p1.

[0346] In at least one embodiment, the needle member may also be coated completely or partially to have hydrophobic or hydrophilic properties depending on the desired outcome. Hydrophobic coatings can be on the order of about 2 pm thick on the outer walls / outer surface of the needle member 5821 that are extended out of the distal end portion of one of the devices described herein.

[0347] As shown in FIG. 58A, the tip sub-assembly 5810 is introduced around the exterior of the eye 10 to access a location of interest. The curved external shape of the tip housing 5820 enables access to the equatorial and posterior sections of the eye 10, where conventional straight needles cannot enter orthogonal to the sclera. The placement can be verified in a number of ways as discussed previously herein as well as in PCT patent application no. PCT / CA2024 / 050924 titled “DEVICES AND METHODS FOR POSTERIOR EYE SEGMENT ACCESS WITH ACCURATE LOCALIZATION AND NEEDLE PENETRATION DEPTH” filed on Thurs, July 11 , 2024, and hereby incorporated by reference in its entirety. With the tip sub-assembly 581 Oin place, suction may be initiated to pull a vacuum in the interior chamber 5820i of the tip housing 5820 via tip-housing vacuum port 5820v (see FIG. 58B). A sufficient amount of vacuum may be used, such as a vacuum pressure on the order about 1 atm for example, to hold the injection site taut during the injection process or drainage process. The interface gasket 5825 can serve to reduce stress concentrations of certain ocular locations such as the conjunctiva and the scleral 5802 layers when pulled towards the needle aperture 5820a.Single gauge needle pivot lever embodiment

[0348] As shown in FIGS. 60A and 60B, in another aspect in of the teachings herein at least one embodiment a needle assembly 6000 may be used with at least one of the devices described herein where the needle assembly 6000 comprises a single gauge needle 6011 , which may be 16 gauge, for example, that also serves as the backbone for a lever section 6011a and curved section 6011 b that is coupled at its end 6011c with a needle holding member assembly that includes a needle holder 6012 which holds a small gauge sharp tip needle 6013 which may be used for fluid insertion I fluid removal as discussed in various embodiments herein. The needle holding member assembly preferably includes a pivot 6010 member that may have trunnionpivots (pins) 6010a and 6010b that are received in a housing section of the main body of the device or housing of the tip sub-assembly. Nominally straight, although it may be locally curved, such as at the distal end, needle section 6011 thus acts as a lever to actuate curved section 6011 b with the attached needle holder 6012 and needle 6013 so that the needle 6013 is extended away from the distal end portion of the device during use so that the needle 6013 may penetrate into an intended organ region of a patient, such as the eye. An appropriate interface (not shown in these figures) towards the free end (e.g., proximal end) of the needle section 6011 interfaces with the cam which a user actuates, as described in various embodiments herein, to move the lever and hence extend and retract the needle.

[0349] As shown in FIGS. 60E-60J, the needle holder 6012 has bores 6012d and 6012e that emanate from an entrance region 6012h. A small bore 6012f may be in fluid communication with the bore 6012 where the small bore 6012f is shaped to match the bore of the curved needle 6013 (see FIG. 60D) and then flares out at 6012g which acts as a fluid conduit (e.g., funnel) into the needle 6013. Body section 6012b is sized for releasable insertion into tip 6011c of the single gauge needle 6011 as shown in FIGS. 60C-60D. Section 6011 d at a distal end of the needle 6011 may be cut at an angle with respect to a longitudinal dimension of tip 6011 c of the needle 6011 and this angled portion mates with angled portion 6012c of the needle holder 6012, thus orienting needle holder 1012 and needle 6013 with respect to the pivot axes of pins 601 a, b of pivot 6010.

[0350] As shown in FIGS. 60C and 60D, and FIGS. 60E-60J, the needle holder6012 has bores 6012d and 6012e where bore 6102e receives the needle straight section 6013b and then bore 6012d receives the needle curved section 6013c when the needle 6013 is slid into place in the needle holder 6012. The needle 6013 being nested into region 6012d prevents the needle 6013 from rotating. Once the needle6013 has been inserted and nested, an adhesive or photocuring polymer may be applied into region 6012h to keep the needle 6013 secured during operation, such as when the needle 6013 is subjected to pressure from fluid coming into the needle for injection through the needle tip into the intended organ region of a patient.

[0351] In at least one embodiment, the needle holder 6012 may be injection molded, and an adhesive used to secure it into the end 6011 c of the needle 6011 . To help reduce the overall height (i.e. , the dimension in the direction of the needle sharp tip section 6013a), the needle holder 6012 may, for example, have bores 6012d and6012e that have an eccentric shape such that the straight sharp tip section 6013a of the curved needle 6013 protrudes from the needle holder 6012, and the curved section 6013b of the needle is fully nested in curved bore section 6012d and straight input section 6012e. As shown, needle holder 6012 and needle end 6011 c have circular cross-sections. To reduce the “height” of the curved tip portion within the device and hence make for a more compact structure better to insert, for example to treat the rear portion of a patient’s eye, the curved region 6011 b may start out circular, near the pivot region, and be increasingly ovular in shape toward the tip, such that distal tip 601 1 c is an oval, where for exam pie the minor diameter, aligned with the direction of the straight portion 6013 of the needle 6013, is half of the major diameter. This may increase flow resistance towards the oval tip region of the needle 6011 by only 12.5% as calculated by matching the perimeter of the oval section to the perimeter of the circular section to calculate the minor and major axes of the ellipse formed, and then calculating the hydraulic diameters of the sections. Examples of applicable parameters (e.g., for the bore of a needle), equations and values for these calculations are shown in Table 2.

[0352] The calculations in Table 2 are good to about 5% for ratio of ellipse diameters up to 3. The diameter savings at the tip of about 0.55mm is useful for an instrument that is inserted into tight spaces (e.g., such as around the back of the eye).

[0353] Referring now to FIGS. 61A-61 D, shown therein are perspective, top, side and top-partially transparent views, respectively of another example embodiment of a needle assembly 6100 featuring an “oval tip” lever assembly in accordance with the teachings herein. The needle assembly 6100 includes a lever arm 611 1 , a pivot cylinder 61 10, a needle holder 6112 and a needle 6013. The lever arm 6111 may be provided using, for example, a 16-gauge needle, with a straight portion and a curved portion 6111 a. The lever arm 6111 extends through the pivot cylinder 6110 (shown in FIGS. 61 A, 61 M and 61 N). The curved portion 6111 a of the lever arm 61 11 has a circular shape / cross-section 6111 c adjacent the pivot cylinder 61 10 and as the curved portion 6111 extends to couple with a needle holder 6112, the shape / cross-section of the curved portion 6111 a becomes flatter to form an end 6111 b having an oval crosssection 6111 o (shown in FIGS. 61A-61 D). FIG. 61 E shows an end view of the curved portion 6111 a with the circular 6111 c and oval 6111 o ends. The dimensions of the parts of needle assembly 6100 may be in accordance with the analysis shown in Table 2.Table 2.

[0354] The oval-shaped needle holder 6112, shown in detail in FIGS. 61G-61 L, holds the needle 6013. The needle holder 6112 includes a narrow portion 6112n and a flanged portion 6112f with a bore 6112b. The narrow portion 6112n is dimensioned to be slidably received within the oval-shaped end 6111 b of the curved arm 6111 of the needle section 6111 and may be held in place via a friction fit or adhesive. The proximal end of the flanged portion 6112f has a shoulder or lip which rests against the end 6111 b of the curved arm 6111 when the needle holder 6112 is in position at the end 6111 b of the curved arm 6111. The bore 6112b at the distal end of the flanged portion 6112f is dimensioned to receive the needle 6113 as was described with respect to FIG. 601 for the embodiment of needle holder 6012. The dimensions and angles shown in FIGS. 61 C, 61 E, 61 F and 61 G are provided as examples and other values may be used in other embodiments.

[0355] The pivot cylinder 6110 is shown in more detail in FIGS. 61 M-61 N. The pivot cylinder 6110 includes a cylindrical body 6110b with a channel / conduit / aperture 6110c that passes through two opposite portions of the sidewall of the body 6110b such that the channel 6110c is parallel with end walls 6001 e of the body 6110b. The 6110c channel is sized to receive the curved arm 6111. The end walls 6001 e have a circular shape and are dimensioned to be received within circular cutouts of the side wall ofthe housing of the tip subassembly so that the curved arm 6111 can pivot allowing the needle 6113 to be extended and retracted during use.

[0356] As shown in FIGS. 62A-62K, shown therein is an example embodiment of a tip sub-assembly 6200 which may be used as a housing with the needle assembly 6100. FIGS. 62A-62C and 62E show rear perspective, side, distal end and cross- sectional side views respectively of the tib sub-assembly 6200 with the needle assembly 6100. FIG. 62D shows a proximal end view of the tip sub-assembly 6200 without the needle assembly 6100. FIGS. 62F and 62G show cross-sectional side views with the tip sub-assembly 6200 including the needle assembly 6100 in a retracted position with the needle 6013 fully contained in the housing of the tip subassembly 6200 and an extended position with the tip of the needle 6013 extending past the housing of the tip sub-assembly 6200. FIGS. 62H-62K show perspective, side, rear and cross-sectional views, respectively, of the tip sub-assembly 6200 without the needle assembly 6100.

[0357] The shape of the tip sub-assembly 6200 is curved to provide a concave lateral surface 6200c for placing adjacent to the human eyeball during use. The curvature of the concave lateral surface 6200c provides a curved instrument tip, which for example, can fit the contour of a human eyeball as explained in other embodiments described herein where different amounts of curvature may be used to reach different locations on the eye. The structure / housing / body 6209 of the tip sub-assembly 6200 may be generally wider at the base 6209b than at the tip 6209t. A bore 6227 within the housing 6209 may comprise a circular cross section and be curved so the tip subassembly 6200 may be injection molded in one piece using a retracting core.

[0358] The tip sub-assembly 6200 is shown may have a projecting skirt 6211 at the base 6209b of the housing 6209 to aid in attachment to an instrument handle (e.g., the end of the main body of the treatment device). In at least one embodiment, the housing 6209 may also be shaped to provide a boss 6213 to accommodate a vacuum passage / channel 6120 through a portion of the housing 6209 and a vacuum port at the base 6209b of the housing. The vacuum port in the skirt that is coupled with a vacuum port on the instrument handle (main body of the treatment device). The device may include a pneumatic ejector, pump, blower or other suitable vacuum source (not shown) that is used to apply a vacuum force through the vacuum channel 6120 to a portion of the lateral curved surface 6200c. In some embodiments, a micro vacuum pump may be used. An aperture / port 6208 on the curved surface 6200c allows theneedle 6013 to be extended therethrough as well as apply the vacuum force to an object that the curved surface 6200c is placed on. In the example embodiment shown, while the boss 6213 is shaped to provide for the vacuum channel 6210 and the vacuum 621 Op, the boss is preferably shaped so that it is not obtrusive. In some examples, the boss 6213 may be shaped so that the vacuum port 621 Op has an oval / el Optical crosssection so that the height of the boss 6213 may be reduced.

[0359] The needle 6013 may deploy through port 6208 when the lever arm 6111 is moved downward by an actuator (i.e. , manual, electric, or pneumatic actuator) such as one of those shown in the embodiments described herein, for example. When a vacuum is applied the pivot cylinder 6110 nests in a cylindrical cavity 6220, seen inFIGS. 62H-62K, and forms an effective seal. Low friction plastics such as, for example, Teflon-based or infused plastics, may be used for the pivot cylinder 6110 and / or the walls of the cylindrical cavity 6220 to enable actuation of the curved arm 6111 and provide lever with minimal deformation. Values for an example embodiment of the needle assembly 6100 and tip subassembly are shown in Table 3.Table 3

[0360] The body of the pivot cylinder 6110 preferably has a diameter substantially equal to the distance from the tip of the needle 6013 to the underside of the needle holder 6112, which for example, in the example embodiment shown herein is about 2.8mm. This allows the needle assembly 6100 to be assembled into the tip subassembly 6200 so that the curved arm 6100 and the tip of the needle 6013 move in an arcing motion. A vacuum applied when the (lower) curved surface 6200c of the tip sub-assembly 6200 is laterally pressed against the sclera of eye, for example, helps to keep the sclera from deflecting away from tip of the needle 6013 due to the initial penetration force of the tip of needle 6013, and thus aids in controllable puncture of the sclera to reduce “snap-through” and the potential puncture of the inner choroid structure.

[0361] FIGS. 62F-62G show the needle 6013 in the retracted and extended positions, respectively, with some example dimensions shown. The body 6209 of the tip sub-assembly 6200, in this example, is sized so that the bore 6227 may accommodate the full height of the tip of the needle 6013 (which in this is example is 2.8mm) and the exposed region of the sharp needle needs to then move through the wall thickness (e.g., typically 0.4mm for example), of the body 6209 plus the depth into / through the sclera that is expected during use.

[0362] As described above, in some embodiments such as those described with respect to FIGS. 58A-58C and 62A-62K, one of the devices described herein can be adapted to provide a vacuum to pull the physiological surface of an object towards the curved distal end portion of the device that is placed against the object during use. As described previously, applying a vacuum (e.g., negative pressure) to pull on the tissue surrounding the needle 6013 and hold the tissue in place (relative to the curved surface of the distal end portion of the device) may prevent deflection of the tissue away from the needle 6013 as the needle 6013 is advanced (e.g., extended). The application of the vacuum may also stiffen the tissue and reduce the amount of force required for the needle tip to penetrate the tissue. The vacuum may also help to separate certain layers of tissue that the needle is being extended into such as by aiding in pulling these layers are apart such as for example, when the needle is being extended through the SOS and choroid, the applied vacuum may aid in by pulling the sclera away from the choroid.

[0363] As shown in FIGS. 63A-63F, in another aspect according to the teachings herein at least one embodiment of a device 6300a may have two or more smallholes / aperture 6302a on a lateral surface 6305 of the distal end portion 6306a of the device 6300 to apply a vacuum pressure, rather than a single hole around the needle hole 6303a can further improve the function of the vacuum. The vacuum apertures 6302a are preferably distributed on either side of the needle hole 6303a and are preferably laterally offset from the needle hole 6303a but may also be located proximally to the needle hole 6303a (as shown) and / or distally (not shown). Preferably the vacuum apertures 6302a have a symmetric layout on the curved surface 6305 of the distal end portion 6306a of the device 6300a but other layouts may be used in other embodiments. As described previously, the device 6300 includes a pneumatic ejector, pump, micro vacuum pump, blower or other suitable vacuum source (not shown) that is used to apply a vacuum force / pressure.

[0364] The device 6300a may also include an indenter 6304 or boss with the needle hole 6303, where the needle will extend from, being located approximately at the center of the indenter 6304. The indenter 6304 may be used to apply force to the surface of the eye to keep the surface taught when the needle is extended into the eye. The indenter 6304 may be optional in this embodiment.

[0365] The device 6300a also includes a transparent surface or window 6301 from which light may be shone from a light source during use to assist the operator with visualization the surface of the eye and possibly certain tissue layers during use. The window 6301 and light source may be optional in this embodiment.

[0366] As shown in FIG. 63G, in another example embodiment of device 6300g having distal end portion 6306g, positive pressure is applied at the center via the needle hole (needle exit location) 6303g to exit from the surface 6305 around the needle when it is deployed to apply positive pressure to the eye (surface of the target) at needle insertion. This assists with combating backflow of fluid or other substances which are ejected from the needle during use. The distal end portion 6306 of device 6300g also includes vacuum holes 6302g disposed to either side of the needle hole 6303g for applying a vacuum in addition to the positive pressure that is provided through the needle hole 6303g. For example, the vacuum holes 6302g may be in the form of slits or rectangular holes as shown in FIG. 63G. Alternatively, there may be an array of vacuum holes (e.g., slots) similar to what was shown in FIG. 63D in the location of vacuum holes 6302g. In another alternative, the vacuum holes 6302g may instead by located vertically on either side of the needle 6303g. In another alternative, the vacuum holes 6202 may be arranged so that they surround the needle hole 6303gand are disposed to the left, right, top and bottom of the needle hole 6303g. In any of these embodiments, the vacuum holes 6302g are on the surface 6305 of the device end portion 6306 to apply negative pressure to hold the sclera during needle insertion as explained earlier. Further, the distal end portion 6306g has a raised surface 6304g that may be rectangular and serves a somewhat similar function as the indenter 6304 of the device 6300a in FIGS. 64D-64F. The raised surface 6304g contains the vacuum holes and makes contact with the eye during use so the vacuum pressure may be applied closer to the eye in this embodiment, rather than the case where the distal portion has a raised indenter 6304 but the vacuum apertures are not raised and are located further away from the surface of the eye where the vacuum is to be applied during use. Accordingly, the embodiment shown in FIG. 63G may allow for the vacuum to attach more strongly to the surface of the eye during use since the vacuum holes are on the lateral surface 6305 that makes first contact with the eye.

[0367] As shown in FIGS. 63H-63I, in another example embodiment of a device 6300h, a distal end portion 6306h of the device 6200h can have walls 6308w with a sealing element 6308s on the end surfaces of the top of the walls 6308w to prevent air from leaking in or out when the seal 6308s makes contact with the surface of the eye during use. The sealing element 6308s may be an external rim to create a seal with the eye surface. In this embodiment, at least one vacuum hole 6302h (e.g., suction aperture) are used to apply a vacuum when the needle 101 is being inserted into the eye. The vacuum holes 6302h may be arranged as described for device 6300a or they may be arranged to have shapes and locations as was described for device 6300g. In this example embodiment, the vacuum holes 6302h are located in the perimeter that is defined by the walls 6308s. Accordingly, there are a plurality of suction apertures disposed about the needle exit location on the lateral surface of the distal end portion of the device. The device 6300h also includes a window 6301 for allowing light to be transmitted from a light source within the device. However, window 6301 may be optional in other embodiments.

[0368] As described previously, such as with respect to FIGS. 34A-36B for example, a light can be transmitted along the needle conduit in at least some embodiments of the devices described herein where the light provides visual guidance during use of the device. Alternatively, in at least one embodiment, a device 6400 can include a light source, such as an LED, at the distal end portion 6406 of the device 6400. FIGS. 64A-64C show perspective, front and side views of an exampleembodiment of a device 6400 and FIGS. 64D-64F are corresponding magnified views of the distal end portion 6406 of the device 400 in which a small LED or other light source is located within the distal end portion 6406 and light generated by the light source is transmitted away from the surface 6405 of the distal end portion 6406 that interfaces (e.g., makes contact) with the eye. By changing the brightness of the light source and the light transmitting properties (e.g., opacity, thickness, etc.) of the surrounding materials, different sized spots can be seen by the operator looking at the front of the eye. The surrounding materials are the materials of the device housing around where the LED I light source is located (or potentially the housing materials of the entire distal end portion).

[0369] For cases where the retina is detached, it may be hard to see a small point of light behind it. In such cases, it is preferable for the size of the transmitted light beam to be larger in order to illuminate the entire indented area and show the operator approximately where the treatment fluid is to be injected. This can be done by having a physically larger LED or other light source, or it can be done by using a semi- translucent material around the LED / light source, such as at the optical window 6401 , leading to a lamp-like effect where a majority of the eye at the distal end portion 6405 of the device 6400 is illuminated.

[0370] A diffuse light may also be desirable in certain procedures such as, for example, in subretinal drainage applications where the surgeon / operator may want to avoid puncturing blood vessels in the choroid in order to reduce, minimize or prevent bleeding. Accordingly, in an example embodiment, it is preferable for the exterior of a substantial portion of the distal end portion of the device to be illuminated, because such devices can backlight the choroid and allow the patterns of the blood vessels to be easily seen by the operator looking in the eye through the pupil.

[0371] For cases where drug delivery to the retina is to be performed, where the anatomy of the eye is intact, it is useful to know very precisely where the drug or other therapeutic fluid / therapeutic drug / therapeutic agent will be injected in order to deliver it away from sensitive areas of the eye or precisely into target areas of the eye. In such drug delivery applications, for example, it is preferable for the size of the transmitted light beam, that is used for localization, to be as small as possible. A small LED can appear as a focused spot of brightness when adjustments are made so that the intensity of the light generated by the LED or other light source is only high enough to be seen through tissue at the center of the transmitted light beam. In an alternativeembodiment, a focusing lens may be placed in front of the LED I light source to make a smaller (i.e. , narrower, more focused) transmitted light beam.

[0372] In some cases, the light source may be operated to provide a blinking light, for example, at a relatively low frequency of approximately 2 Hz, which may make it easier for the operator to see and distinguish from surrounding tissue. Other parameters for the frequency and / or duty cycle may also be used. Changes in intensity of the light (e.g., either discrete or continuous), may also be used instead of only switching the light between on and off.

[0373] It is preferrable for the light to be located as close as possible to the needle exit point 502 so that there is not a significant distance between the transmitted light beam (e.g., the light point or focal point) and the actual needle insertion location. This also helps the operator to position the device at the target needle insertion location more precisely. For example, the optical window 6401 may be adjacent the needle hole 6403 or the indenter 6404 (if an indenter is used). It should be noted that the indenter 6404 is optional in some embodiments. Also, the light source and the optical window 6401 in the distal end portion of the device 6400 may be used in at least one other device embodiment described herein such as the device 6300a, 6300g or6300h where the light source and optical window may be combined with the use of suction holes / openings / apertures.

[0374] For embodiments in which the device has two parts where one part is reusable and the other is disposable, the LED / light source may be located in the disposable half of such devices and thus, thrown away after use. Examples of devices with disposable portions are described with respect to FIGS. 50A-50C and FIGS. 51 A- 51 E. In such embodiments, the wires to power the LED / light source may run through a small channel from the distal end portion of the device to a mating plane (e.g., mechanical and electrical interface) between the reusable and disposable parts of the device. At this interface, an electrical connector may be used to bring power from a battery in the backend (e.g., reusable portion of the device) to the LED I light source located in the distal end portion of the device.

[0375] In alternative embodiments, it may be desired to deliver the light beam through the bore of the needle in order to visually indicate to the operator that the needle tip is in the correct space. In cases when considering light delivery through the needle bore, it is preferable for the end of the light fiber (aka optical fiber), that is transmitting the light from a light source, to be as close to the end of the tip of theneedle as possible. This is because light coming out of an optical fiber is not collimated and thus may quickly scatter and lower in intensity, making it hard to see the tissue when the light source is not efficiently coupled to the needle and the light source is far from the tissue.

[0376] For example, referring now to FIG. 65A shown therein is a needle 6501 having a needle shaft 6503, as well as needle bore 6504 within the needle shaft 6503 and having a needle bore opening 6508. A fiber optic (i.e. an optical fiber) 6511 is located within the needle bore 6504. If the end of the fiber optic 6511 is aligned with the proximal end of the needle bore opening 6508, and the distance from the proximal end of the needle bore opening 6508 to the needle tip is longer than the thickness of the SCS, then when the needle tip is at the far side (the choroid side) of the SCS then the end of the fiber optic 6511 will still be located within the sclera (if the distance from the needle tip to the end of the fiber optic 6511 is less than the thickness of the sclera and SCS) or outside the eye entirely (if the distance from the needle tip to the end of the fiber optic 6511 is more than the thickness of the sclera and SCS).

[0377] The risk that the end of the fiber optic may be located too far away from the tissue being examined to provide proper illumination may be mitigated by providing an optical coating 6501 m the inside of the needle bore 6504 where the optical coating 6501 m may be a thin layer of plastic, glass, or other light transmitting material 6501 m such as for needle 650T shown in FIG. 65B. The optical coating 6501 m may act like a fiber optic that is shaped like an annulus along the inner diameter of the needle 650T. The needle 650T can then be cut normally resulting in the optical coating being flush with the needle face 6501f, as shown in in FIGS. 65B and 65C. Any fluid or substance to be delivered to the eye then flows through the central bore 6504. In some embodiments, there may also be one or more bevel segments 6501 b at the needle face 6501f.

[0378] In some embodiments, the needle actuation may be desired to be motorized in order to give the operator even finer control of the needle tip position and / or reduce operator hand and finger motion required. The motorization of the needle actuation may also allow for steadier positioning of the device in some cases.

[0379] For example, referring now to FIGS. 66A-66C, shown therein are side, front and cross-sectional side views, respectively, of a portion of an example embodiment of a device 6600 that has a motorized needle advancement assembly for motorized needle actuation. The device 6600 is somewhat similar to the embodiment of FIGS.30A-30C but it should be noted that the motorized design for device 6600 may be used with other device embodiments described herein. The motorized needle advancement assembly of the device 6600 includes a wheel 6601 with a central spiral slot 1602 (aka a cam slot) which acts as a cam for moving a needle holding member 6606 (aka beam), teeth 6603 on the wheel, a worm gear 6604 that has teeth / gears that are drivingly coupled to the teeth 6603 of the wheel 6601 and a motor shaft 6605 along with a motor (not shown). The worm gear 6604 is attached to the motor shaft 6605 that is rotationally coupled to the motor. The needle position (e.g., retracted or extended) is still controlled by the beam 6606 rotating about a pivot with the proximal end of the beam 6606 engaged with the cam slot 6602 inside the wheel 6601 . The user may interact with a control button or mechanical slider (both not shown) to control the operation of the motor which ultimately moves the beam 6606 a certain amount for a desired amount of needle extension.

[0380] Additionally, having the wheel 6601 visible is valuable, as it can show the operator how far the needle tip has been advanced by including indicators / markers on the wheel 6601 . The operator may not be able to manually adjust the wheel 6601 , in this embodiment, since the worm gear drive is not backwards drivable. However, there may be other embodiments where the needle may be driven either manually or with a motor by using a chain of gears with a low overall reduction ratio.

[0381] In another aspect, in at least one embodiment, the motorized device 6600 of FIGS. 66A-66C can be modified to target the subretinal space rather than the suprachoroidal space. In such a case, the device uses a slightly longer needle and a tip arc angle that is larger to reach farther back in the eye. All other needle actuation elements may remain the same.

[0382] In subretinal drug delivery, the back end of the device may be the same as some of the embodiments described herein as well as in PCT Patent Application no. PCT / CA2024 / 050924, for the fluid delivery configurations / structure / design. Referring now to FIGS. 67A-67C, shown therein are side, front and perspective views of an example embodiment of a device 6700 that may receive an empty container or syringe 6701 for performing drainage where the syringe 6701 is not yet inserted into the device 6700. FIG. 67D shows a cross-sectional view of the device 6700 with the syringe 6701 inserted into a channel or cavity 802 that runs along a longitudinal portion of the device 6700. The device 6700 may be referred to as a drainage device such as a subretinal drainage device, where the backend, which is typically used for fluid delivery (aka afluid delivery backend) in the various device embodiments described herein, may be replaced with a drainage backend that can receive the empty syringe 6701. The syringe 6701 is inserted into the channel 6702 so that a seal 6701 s of the syringe 6701 is pushed onto a dispensing needle 6703 which breaks the seal 6701 s, which might be a rubber, plastic, or foil seal, for example.

[0383] A needle (not shown) which is used to perform drainage is located at the distal end portion 6711 of the device 6700 and may be operated and implemented according to one or more of the device embodiments described herein. A control wheel / knob 6712 may be used to actuate (e.g., extend or retract) the needle by rotating a spiral cam 6714 that in turn actuates a needle member / beam 6715 as was described in an earlier embodiment. The wheel 6712 has numbers / indicators on a side surface so that the operator knows how far the needle tip is extended pas the lateral surface of the distal end portion 6711 which makes contact with the eye during use.

[0384] The device 6700 includes a front end 6705 and a back end 6706 which allows the device 6700 to have the back end 6706 be interchanged between a drainage backend (as shown) or a fluid delivery backend (not shown). The front end 6705 may be disposable in some embodiments and the back end 6706 can be reusable. The front-end 6705 and the back-end 6706 may be releasably connected to one another through a locking mechanism such as luer lock 6704, for example, although other locking mechanism may be used such as screws, hook and groove, etc.

[0385] The back-end 6706 of the device 6700 includes the vial 6701 , fluid control mechanism / assembly, electronic hardware 6707 such as processing circuitry, a battery and optionally a motor, as was described for the device in FIGS. 66A-66C, in which case the wheel 6712 cannot be used to manually control the extension or retraction of the needle. The front end 6705 includes a channel 6708 through which electrical wiring can be passed to any electronic components in the distal end portion 6711 such as an LED or other light source, for example. The back-end 6706 includes an electrical connector for connecting the wiring in the channel 6708 to the appropriate hardware 6707. Alternatively, the LED or light source may be in the back-end in which case a fiber optic may located within the channel 6708 and used to transmit light from the light source to a section of the distal end portion of the device, such as the needle exit hole. The back-end may include other high-value components that are preferred to be reused. In general, the back-end may contain a fluid container, fluid controlmechanism / assembly, and electronic hardware (e.g., processing circuitry, a battery and / or a motor).

[0386] In some embodiments, the inside of the syringe 6701 can be kept at atmospheric pressure, and the higher pressure inside the eye pushes fluid into the needle at the distal end portion 6711 of the device 6700 through a conduit to the needle 6703 into the syringe 6701 . If additional negative pressure is needed, a syringe having a plunger can be used in which case the operator pulls back on the plunger to create a vacuum inside the syringe to pull fluid out from the eye. In other embodiments, the syringe may be replaced with another device that generates a negative pressure such as a vitrectomy machine or a pump, for example.

[0387] Accordingly, in device embodiments that provide drainage, the device comprises an empty syringe at atmospheric pressure, a syringe with a plunger, or a syringe attached to a suction machine configured to attach to a drainage needle path for draining fluid out of the target (e.g., a region of the eye).

[0388] Referring now to FIGS. 68A-68E, shown therein are rear, side, rearperspective, front, cross-sectional side, front-perspective and magnified views, respectively, of another example embodiment of a device 6800. The device 6800 may be used to inject treatment fluid into or remove fluid from a physiological body such as a patient’s eye for example. The device 6800 may have a smaller size compared to other designs described herein. A portion of the device 6800, e.g., a needle tip subassembly 6801 , may be single use and disposable. The needle tip sub-assembly 6801 which is removably attachable (releasably connectable) to a distal end of a main body 6802 of the device 6800.

[0389] The device 6800 includes a needle 6810 that is part of the tip sub-assembly 6801 and is used to perform fluid injection or fluid drainage. The needle 801 is located at a distal end portion 6811 of the device 6800 and may be operated and implemented according to one or more of the device embodiments described herein. However, in the example embodiment of FIGS. 68A-68E, the device includes a control wheel 6812 that may be used to actuate (e.g., extend or retract) the needle 6811 by rotating a spiral cam 6806 that in turn actuates a needle member / beam 6815 as was described in an earlier embodiment. The device 6800 may have numbers / indicators on a surface of the housing adjacent to the wheel 6812 so that the user knows how far the tip of the needle 6810 is extended past the lateral surface of the distal end portion 6811 of the device 6800 where the lateral surface 6811 LS makes contact with the eye during use.In this embodiment, the back wall of the distal end portion 6811 may be removed to provide an open back surface 6811 bw or shaved off to reduce the thickness of the distal end portion 6810 of the device 6800 which results in a reduced profile that allows the distal end portion 6801 of the device to more easily be placed in smaller locations such as the space between a posterior region of a patient’s eye and the orbital bone.

[0390] The device 6800 includes vial 6817 that is fluidically coupled to the needle 6810. The vial 6817 may include treatment fluid or it may be empty and used for draining purposes. The device 6800 includes a plunger 6818 that is moveable and is coupled to located above the vial 6817. When the plunger 6818 is moved downwards a force is applied to the vial to move the treatment fluid to the needle 6810. Alternatively, if the vial 6817 is empty and used for drainage then the plunder 6818 is moved upwards. The device 6800 includes a motor 6813 (e.g., a DC motor) with a gear box and a lead screw system 6814 that are both located in a proximal portion of the device 6800. When the motor 6813 is turned on a rotational force is applied to the screw system 6814 to move the plunger 6818 down or up, depending on the direction of rotation of the motor 6813, to dispense fluid or drain fluid, respectively.

[0391] In some embodiments, the outer surface of the main body of the device 6800 includes a textured surface 6814 to increase friction and provide extra grip to a user of the device 6800. The textured surface 6814 may be located only on a bottom portion of the device 6800 where the fingers of the user are more likely to hold the device 6800. The location of the textured surface 6814 also provides tactile feedback to the user as to the orientation of the device 6800 when the user grabs or holds the device 6800

[0392] In some embodiments, a proximal angular portion 6815 of the device 6800 is curved such that the device 6800 has an oval or elliptical shape such that it conforms to the user’s hand between the thumb and index finger of the user to provide the user stability while operating the device 6800. The oval shape of the proximal portion of the body of the device 6800 also gives tactile feedback so that the user knows the proper vertical and horizontal orientation of the device 6800 when it is being held by the user.

[0393] The device 6800 also includes a cable 6816 at the proximal end of the device 6800 that houses electrical wires which can be used to provide power and control signals to the device 6800. For example, the device 6800 may be connected to an external control mechanism via the cable 6816. For example, the external control mechanism may be a foot pedal (not shown) which allows the user to control the motor6813 for fluid injection or fluid drainage without using the hand holding the device 6800. This enables the user to simultaneously control of the movement of the needle 6810 via the wheel 6812 with one of the user’s hands while the user may use the external controller (e.g., via a foot pedal) to control the motor 6814 so that minimal movement is required to turn the motor 6814 on and off.

[0394] It should be noted that the local surface around the needle exist locations on the distal end portion of the various embodiments taught herein may be concave and or convex. For more anterior targets, it may be beneficial to have the needle exit from a convex surface (i.e. curving away from the eye) so that the operator can hold the device such that the handle is tilted away from the eye (and therefore does not block the operator’s field of view) while the distal end portion of the device still makes contact with the eye (at the point on the convex surface where the needle exits from in this example).

[0395] It should be noted that the components of the various embodiments described herein that cooperate with one another to deliver fluid to a needle may collectively be referred to as a fluid delivery assembly or fluid delivery system.

[0396] While the applicant's teachings described herein are in conjunction with various embodiments for illustrative purposes, it is not intended that the applicant's teachings be limited to such embodiments. On the contrary, the applicant's teachings described and illustrated herein encompass various alternatives, modifications, and equivalents, without generally departing from the embodiments described herein. For example, while the teachings described and shown herein may comprise certain elements / components and steps, modifications may be made as is known to those skilled in the art. For example, selected features from one or more of the example embodiments described herein in accordance with the teachings herein may be combined to create alternative embodiments that are not explicitly described. For example, as will be clear to a person having ordinary skill in the art, the devices and methods described herein may be implemented using other additional combinations and permutations of the various features and functions presented including shape, form factor, needle position or orientation, conduits, adjustments, controls, actuators, indicators, guidance elements, fluids and other materials, procedure steps, and applications. All values and sub-ranges within disclosed ranges are also disclosed. The subject matter described herein intends to cover and embrace all suitable changes in technology.REFERENCES[1] S. E. Hancock, C.-R. Wan, N. E. Fisher, R. V. Andino, and T. A. Ciulla, “Biomechanics of suprachoroidal drug delivery: From benchtop to clinical investigation in ocular therapies,” Expert Opin. Drug Deliv., vol. 18, no. 6, pp. 777-788, Jun. 2021 , doi: 10.1080 / 17425247.2021 .1867532.[2] K. Y. Wu, J. K. Fujioka, T. Gholamian, M. Zaharia, and S. D. Tran, “Suprachoroidal Injection: A Novel Approach for Targeted Drug Delivery,” Pharmaceuticals, vol. 16, no.9, Art. no. 9, Sep. 2023, doi: 10.3390 / ph16091241 .[3] R. H. Muni, I. M. Melo, A. Pecaku, A. Mannina, H. Batawi, and A. Bansal, “In-Office Suprachoroidal Viscopexy for Rhegmatogenous Retinal Detachment Repair,” JAMA Ophthalmol., Aug. 2023, doi: 10.1001 / jamaophthalmol.2023.3785.[4] C. Boote, I. A. Sigal, R. Grytz, Y. Hua, T. D. Nguyen, and M. J. A. Girard, “Scleral structure and biomechanics,” Prog. Retin. Eye Res., vol. 74, p. 100773, Jan. 2020, doi: 10.1016 / j.preteyeres.2O19.100773.[5] V. Manjunath, M. Taha, J. G. Fujimoto, and J. S. Duker, “Choroidal Thickness in Normal Eyes Measured Using Cirrus-HD Optical Coherence Tomography,” Am. J. Ophthalmol., vol. 150, no. 3, pp. 325-329. e1 , Sep. 2010, doi: 10.1016 / j.ajo.2010.04.018.[6] C. Boote, I. A. Sigal, R. Grytz, Y. Hua, T. D. Nguyen, and M. J. A. Girard, “Scleral structure and biomechanics,” Prog. Retin. Eye Res., vol. 74, p. 100773, Jan. 2020, doi: 10.1016 / j.preteyeres.2O19.100773.[7] V. Manjunath, M. Taha, J. G. Fujimoto, and J. S. Duker, “Choroidal Thickness in Normal Eyes Measured Using Cirrus-HD Optical Coherence Tomography,” Am. J. Ophthalmol., vol. 150, no. 3, pp. 325-329. e1 , Sep. 2010, doi: 10.1016 / j.ajo.2010.04.018.[8] A. Vogel, C. Dlugos, R. Nuffer, and R. Birngruber, “Optical properties of human sclera, and their consequences for transscleral laser applications,” Lasers Surg. Med., vol. 11 , no. 4, pp. 331-340, 1991 , doi: 10.1002 / lsm.1900110404.

Claims

CLAIMS:

1. A device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device; a needle that is moveable and disposed at the distal end portion of the device; a needle holding member that is disposed within the housing, the needle holding member being moveable, and the needle being located at a distal end portion of the needle holding member; and a needle movement control mechanism coupled to the needle holding member, the needle movement control mechanism being actuatable to cause the needle holding member to extend the needle through a needle exit location on a lateral surface of the distal end portion of the device at an angle to a longitudinal axis of the distal end portion of the device.

2. The device of claim 1 , wherein the needle movement control mechanism is also reversibly actuatable to retract the needle into the housing.

3. The device of claim 1 or claim 2, wherein an angular orientation of the needle as it is extended from the lateral surface of the distal end portion of the device ranges from about 45 degrees to about 135 degrees with respect to a plane tangent to the lateral surface at the needle exit location.

4. The device of claim 3, wherein the angular orientation of the needle as it is extended from the lateral surface of the distal end portion of the device is about 90 degrees with respect to the plane tangent to the lateral surface at the needle exit location.

5. The device of any one of claims 1 to 4, wherein the lateral surface of the distal end portion of the device has a flat portion or a curved portion.

6. The device of claim 5, wherein a portion surrounding the needle exit location on the lateral surface of the distal end portion of the device is concave to conform to an outer surface of the eye.

7. The device of claim 5, wherein a portion surrounding the needle exit location on the lateral surface of the distal end portion of the device is convex to indent an outer surface of the eye.

8. The device of any one of claims 5 to 7, wherein a radius of curvature of the lateral surface of the distal end portion of the device matches a radius of curvature to within 20% of a location of the target where the needle is inserted.

9. The device of any one of claims 5 to 7, wherein the lateral surface of the distal end portion of the device is curved and has an arc angle between about 5 degrees to about 90 degrees.

10. The device of any one of claims 5 to 7, wherein the lateral surface of the distal end portion of the device is curved and has an arc angle between about 30 degrees to about 60 degrees.

11. The device of any one of claims 1 to 10, wherein the longitudinal axis of the distal end portion of the device at a region intersecting with a longitudinal axis of the main body has a negative tilt angle with respect to the longitudinal axis of the main body.

12. The device of claim 11 , wherein the tilt angle is between about 0 and about -90 degrees and the title angle is more preferably about -30 degrees.

13. The device of any one of claims 1 to 12, wherein a portion of the needle movement control mechanism is disposed on the housing and includes a rotational dial, knob, button, or wheel.

14. The device of any one of claims 1 to 13, wherein the needle movement control mechanism is coupled to a portion of the needle holding member via a cam and the cam is rotatable to cause the needle holding member to move when the needle movement control mechanism is actuated.

15. The device of any one of claims 1 to 14, wherein the needle holding member is in a simply supported arrangement where a proximal end portion of the needle holding member is fixed.

16. The device of claim 14, wherein the device further comprises a slot actuating member that has an angled slot at a distal end portion thereof and the needle holding member has a pin at the distal end portion that slidably engages the slot so that when the slot actuating member is moved, the pin moves along the slot causing the distal end portion of the needle holding member to cause the needle to move.

17. The device of claim 16, wherein the slot has straight segments with different angles that cause the needle to move at a faster or slower rate when the pin moves through the segments.

18. The device of claim 16, wherein the slot has a curved segment that causes the needle to move at a faster or slower rate when the pin moves through the curved segment depending on curvature of the curved segment.

19. The device of any one of claims 16 to 18, wherein the needle movement control mechanism is coupled to a proximal portion of the needle holding member via the cam so that rotation of the cam during actuation of the needle movement control mechanism causes the slot actuating member to move.

20. The device of any one of claims 1 to 13, wherein the needle holding member includes a pivoting mechanism where a position of a proximal end portion of the needle holding member is controlled by the needle movement control mechanism and a pivot point is located adjacent a distal end portion of the needle holding member wherein movement of the proximal end portion of the needle holding member causes the needle to move.

21. The device of any one of claims 1 to 13, wherein the needle holding member has a pivot member that is located between the distal and proximal end portions of the needle holding member and supported by a pivot bore in the housing, such that when the proximal end portion of the needle holding member receives a displacing force when the needle movement control mechanism is actuated, the distal end portion of the needle holding member is moved causing the needle to move.

22. The device of any one of claims 1 to 13, wherein the needle holding member is an elastically deformable beam having a proximal end portion and a distal end portion, wherein the proximal end portion is prevented from displacing, and a pivot support is located between the proximal and distal end portions, wherein when an actuating force is applied to the beam between the pivot support and the proximal end portion, the distal end portion is displaced to cause the needle to move through the lateral surface of the distal end portion of the device.

23. The device of claim 22, wherein the elastically deformable beam has a medial portion that extends from the pivot to an actuating force location where the distal end and medial portions are stiffer than the proximal end portion of the needle holdingmember to reduce deflection of the needle under needle insertion forces, where the deflection due to the needle holding member at the base of the needle is less than 30% of an intended total motion of the needle tip.

24. The device of any one of claims 1 to 23, wherein the needle movement control mechanism includes a wheel having a cam and the proximal portion of the needle holding member includes a cam-engagement structure so that when the needle movement control mechanism is actuated, the wheel and the cam rotate and thereby move the proximal end portion of the needle holding member.

25. The device of any one of claims 1 to 23, wherein the needle movement control mechanism includes a split wheel having two wheel halves and a cam located therebetween and coupled to the wheel halves, and the proximal portion of the needle holding member is shaped to fit between the wheel halves and be adjacent to the cam so that when the needle movement control mechanism is actuated, the wheel and the cam rotate to move the proximal end portion of the needle holding member.

26. The device of any one of claims 1 to 13, wherein the needle movement control mechanism includes a wheel with a central axis of rotation and a spiral slot on a side face and the proximal portion of the needle holding member includes a pin at a proximal end portion thereof where the pin slidably engages the spiral slot and when the needle movement control mechanism is actuated, the spiral slot rotates causing the pin are to move laterally thereby moving the proximal end portion of the needle holding member.

27. The device of any one of claims 1 to 13 wherein the needle movement control mechanism includes a split wheel having two opposing wheel halves each having a common axis and a spiral cam slot on a side face, the slots facing each other and having a common axis of rotation, the proximal portion of the needle holding member is disposed between the wheel halves and includes a slot engagement member that slidably engages the spiral slots and the main body and when the needle movement control mechanism is actuated, the spiral slots rotate about the common axis and the pin is moved laterally thereby applying a displacing force to the proximal end portion of the needle holding member.

28. The device of any one of claims 22 to 26, wherein the needle movement control mechanism includes a wheel having bumps, slots, depression or other physicalindicators around a circumference thereof to provide traction and tactile feel to a user of the device as the user rotates the wheel to actuate the needle.

29. The device of claim 27, wherein the bumps vary in width and / or circumferential length over a rotation range of the wheel to provide tactile feedback to the user as to a distance the needle is protruding from the lateral surface of the distal end portion of the device.

30. The device of any one of claims 1 to 13, wherein the needle movement control mechanism includes a wheel having a cam and the proximal end portion of the needle holding member has a contact member that engages the cam so that when the needle movement control mechanism is actuated, the cam rotates to apply force to the contact member of the proximal end portion of the needle holding member to move the needle holding member.31 . The device of any one of claims 1 to 13, wherein the needle movement control mechanism includes a wheel having a cam and the proximal end portion of the needle holding member has a lever mechanism having a proximal end that engages the cam such that movement of the cam causes the needle holding mechanism and the needle to move in response.

32. The device of any one of claims 1 to 31 , wherein the needle movement control mechanism includes visual distance measures to indicate how far the needle tip is advanced when the needle movement control mechanism is actuated.

33. The device of any one of claims 1 to 32, wherein the needle movement control mechanism includes a ratchet mechanism provided by a rounded or tapered protrusion on the wheel that contacts an extended semi-flexible member attached to the main body which provides resistance to turning the wheel but also yields and allows further movement to provide a user with tactile feedback when actuating the needle movement control mechanism.

34. The device of claim 33, wherein the ratcheting mechanism is a reversible ratchet to allow for retraction of the needle.

35. The device of any one of claims 1 to 34, wherein a distal end portion of the needle holding member has a greater thickness and is stiffer than a medial portion of the needle holding member.

36. The device of any one of claims 1 to 35, wherein the device further comprises a treatment fluid container and optionally a drainage chamber.

37. The device of claim 36, wherein the treatment fluid container is coupled to the needle holding member so that movement of the needle holding member to advance the needle also causes an increase in fluid injection pressure.

38. The device of claim 37, wherein the treatment fluid container is coupled to the needle holding member via an elastic element that is positioned therebetween and a mechanical element that is moved by a control input.

39. The device of claim 36, wherein the device further comprises a fluid control mechanism for fluid injection and / or drainage.

40. The device of claim 39, wherein the fluid control mechanism is a mechanical slider, button, wheel or electrically powered motor extendable member that is coupled to an internal plunger of the device to push fluid out of the treatment fluid container and into the needle to be delivered to the target.41 . The device of any one of claims 36 to 40, wherein the treatment fluid container contains a viscoelastic fluid or a therapeutic drug to be delivered to the target, the target being a desired location within a patient.

42. The device of any one of claims 1 to 41 , wherein the device further comprises a light pipe or an optical fiber that extends to the distal end portion of the device, where a light source is coupled to the light pipe or the optical fiber.

43. The device of any one of claims 1 to 42, wherein the device comprises a fluid pipe that extends to the distal end portion of the device and is coupled to the needle where the fluid pipe is used to deliver treatment fluid to the needle or receive drainage elements from the needle.

44. The device of claim 43, wherein the fluid pipe and the light pipe or the optical fiber are delivered to the needle through a single diameter or a stepped passageway of successively smaller diameters.

45. The device of any one of claims 43 to 44, wherein the fluid pipe is used as the light pipe, using reflection of light from internal walls of the needle to guide the light.

46. The device of claim 45, wherein a hollow optical waveguide acts as the fluid pipe and the light pipe.

47. The device of any one of claims 43 to 46, wherein a distal portion of the fluid pipe is tapered.

48. The device of any one of claims 42 to 47, wherein the light source is internal or external to the main body of the device.

49. The device of claim 48, wherein the light source is configured to generate a light at the distal end portion of the device which indicates to an operator a location of the device distal end portion of the device relative to the target.

50. The device of any one of claims 42 to 49, wherein the device includes a mirror, a prism or a photonic crystal and when the needle is oriented to be inserted into the eye, the mirror, prism or photonic crystal is used to efficiently redirect light from projecting along the main body of the device to project inside the needle as the needle is moved through the lateral surface of the distal end portion of the device for insertion into the sclera.

51. The device of any one of claims 1 to 50, wherein the device includes at least one protrusion on the lateral surface at the end portion of the device and the needle is extended through the at least one protrusion.

52. The device of any one of claims 1 to 51 , wherein the device is separable into a proximal portion or back-end housing a and a distal portion or front-end housing, wherein the back-end housing houses the vial, fluid control mechanism, and electronics and the front end houses the needle holding member and the needle.

53. The device of any one of claims 1 to 52, wherein the device comprises a tip sub-assembly that is releasably connectable to a distal end of a lower portion of the main body of the device.

54. The device of any one of claims 1 to 53, wherein the device comprises a suction channel at the lateral surface of the distal end portion of the device to apply suction to a surface of the target during needle insertion into the target.

55. The device of claim 54, wherein the suction channel is coupled to at least one suction aperture on the lateral surface of the distal end portion of the device.

56. The device of claim 54, wherein the suction channel is coupled to a plurality of suction apertures disposed about the needle exit location on the lateral surface of the distal end portion of the device.

57. The device of any one of claims 1 to 56, wherein a positive pressure is applied to an aperture at the needle exit location that the needle is extended through to apply positive pressure to the surface of the target at needle insertion.

58. The device of any one of claims 1 to 57, wherein the device comprises a reflective coating inside a bore of the needle to enable the bore of the needle to function as a light pipe for transmitting light along the needle.

59. The device of any one of claims 1 to 58, wherein the device comprises a raised surface the needle exit location on the lateral surface of the distal end portion of the device so that when a user presses the raised surface against the sclera, a tension is created in a scleral surface to enable the needle to more easily penetrate into the sclera with less pushing away of the sclera.

60. The device of any one of claims 1 to 59, wherein the device comprises an empty syringe at atmospheric pressure, a syringe with a plunger, or a syringe attached to a suction machine configured to attach to a drainage needle path for draining fluid out of the target.

61. The device of any one of claims 1 to 60, wherein the device comprises a motorized needle advancement assembly for move the needle with respect to the lateral surface at the distal end portion of the device.

62. The device according to any one of claims 1 to 61 , wherein the device comprises a motor for actuating fluid delivery, a sensor for sensing a change in magnitude of current drawn by the motor due to changing torque based on fluid flow, and a sensor for sensing a change in frequency of the current drawn by the motor due to back Electromotive Force (EMF) due to change in motor speed due to changing fluid pressure and a controller for receiving sensor signals indicating any changes in the magnitude and frequency of the current drawn by the motor.

63. The device of claim 62, wherein the controller is adapted to provide alerts corresponding to changes in fluid flow and fluid pressure based on the measured changes of the magnitude and the frequency of current drawn by the motor, respectively.

64. A device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device;a moveable needle disposed at the distal end portion of the device; and a suction channel disposed at the distal end portion of the device to apply suction to a surface of the target during needle insertion into the target.

65. The device of claim 64, wherein the suction channel is coupled to at least one suction aperture on the lateral surface of the distal end portion of the device.

66. The device of claim 64 or claim 65, wherein the suction channel is coupled to a plurality of suction apertures disposed about the needle exit location on the lateral surface of the distal end portion of the device.

67. The device of any one of claims 64 to 66, wherein a positive pressure is applied to an aperture at the needle exit location that the needle is extended through to apply positive pressure to the surface of the target at needle insertion.

68. The device of any one of claims 64 to 67, wherein the device further comprises: a needle holding member that is disposed within the housing, the needle holder being moveable, and the needle being located at a distal end portion of the needle holding member; and a needle movement control mechanism coupled to the needle holding member, the needle movement control mechanism being actuatable to cause the needle holding member to extend the needle through a needle exit location on a lateral surface of the distal end portion of the device at an angle to a longitudinal axis of the distal end portion of the device, wherein the device is further defined according to any one of claims 2 to 53 or 58 to 63.

69. A device for injecting and / or removing substances from a target, wherein the device comprises: a housing defining a main body and a distal end portion of the device; a moveable needle disposed at the distal end portion of the device; a needle holding member that is disposed within the housing, the needle holder being moveable, and the needle being located at a distal end portion of the needle holding member; a fluid delivery assembly for injecting a treatment fluid into the target, and a needle movement control mechanism coupled to the needle holding member and the fluid delivery assembly.wherein the needle movement control mechanism is actuatable to cause the needle holding member to move the needle through a needle exit location into the target and to cause the fluid delivery assembly to deliver the treatment fluid to the needle.

70. The device of claim 69, wherein the needle exit location is on a lateral surface of the distal end portion of the device and the device is further defined according to any one of claims 2 to 36 and 38 to 63.71 . The device of any one of claims 1 to 70, wherein the target is a portion of the eye.

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