Injection device for subretinal delivery of therapeutic agents - Patent Application 20070122997

Abstract

An apparatus for injection for subretinal delivery of a therapeutic agent is provided. [Solution] The device includes an injector assembly, an injector driver, a fluid supply assembly, and a magnetic pad assembly, wherein the injector assembly includes a body, a flexible cannula, and a needle, the magnetic pad assembly is sized and configured to be placed on a patient's forehead, the magnetic pad assembly includes an adhesive, the body of the injector assembly is configured to be removably secured to the magnetic pad assembly, the injector assembly further includes a magnet, the magnet is configured to removably secure the body to the magnetic pad assembly via magnetic attraction, the magnet is held in a stationary position relative to the body, and the syringe driver is operable to drive the needle longitudinally relative to the magnet.

Description

Disclosure Contents

[0001] [Right of priority] This application claims priority to U.S. Provisional Patent Application No. 62 / 351,628, filed June 17, 2016, entitled "Subretinal Injection Device," the disclosure of which is incorporated herein by reference.

[0002] 〔background〕 The human eye contains several layers. The white outer layer is the sclera, which surrounds the choroid layer. The retina lies inside the choroid layer. The sclera contains collagen and elastic fibers, providing protection to the choroid and retina. The choroid layer contains the vasculature, which provides oxygen and nutrients to the retina. The retina contains light-sensitive tissue, including rods and cones. The macula is located in the center of the retina at the back of the eye and is generally centered on an axis (i.e., the visual axis) that passes through the center of the eye's lens and cornea. The macula provides central vision, particularly through cone cells.

[0003] Macular degeneration is a medical condition that affects the macula. People with macular degeneration may experience loss or degeneration of central vision while retaining some peripheral vision. Macular degeneration can be caused by a variety of factors, including age (also known as "AMD") and genetics. Macular degeneration can occur in a "dry" (non-exudative) form, in which cellular debris known as drusen accumulates between the retina and choroid, resulting in areas of geographic atrophy. Macular degeneration can also occur in a "wet" (exudative) form, in which blood vessels grow from the choroid behind the retina. Even if people with macular degeneration may retain some peripheral vision, the loss of central vision can significantly impact quality of life. Furthermore, the quality of remaining peripheral vision can deteriorate and, in some cases, even disappear. Therefore, it may be desirable to provide treatments for macular degeneration to prevent or reverse the vision loss caused by macular degeneration. In some cases, it may be desirable to provide such treatment in a highly localized manner, such as by delivering a therapeutic agent near the macula within the subretinal layers (below the neurosensory layer of the retina and above the retinal pigment epithelium) immediately adjacent to the area of ​​geographic atrophy. However, because the macula lies beneath the delicate layers of the retina at the fundus, it can be difficult to access the macula in a practical manner.

[0004] Although various surgical methods and instruments have been created and used to treat the eye, it is believed that no one prior to the inventors has made or used the claimed invention.

[0005] While the specification concludes with claims that particularly point out and distinctly claim this technology, it is believed that this technology will be better understood from the following description of specific embodiments taken in conjunction with the accompanying drawings, in which like reference numerals identify the same elements.

[0006] The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the technology may be implemented in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate several aspects of the technology and, together with the description, serve to explain the principles of the technology; it is understood, however, that the technology is not limited to the precise configurations shown.

[0007] Detailed Description The following description of specific examples of the technology should not be used as limiting its scope. Other examples, features, aspects, embodiments, and advantages of the technology will become apparent to those skilled in the art from the following description, which is, by way of example, one of the best modes contemplated for carrying out the technology. As will be recognized, the technology described herein is capable of other distinct and obvious aspects without departing from the technology. Accordingly, the drawings and descriptions should be regarded as illustrative in nature, and not as restrictive.

[0008] It is further understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Accordingly, the teachings, expressions, embodiments, examples, etc. described below should not be considered in isolation from one another. Various suitable ways in which the teachings herein may be combined will be readily apparent to those skilled in the art in view of the teachings herein. Such modifications and variations are intended to be within the scope of the claims.

[0009] For clarity of disclosure, the terms "proximal" and "distal" are defined herein with respect to a surgeon or other operator grasping a surgical instrument having a distal surgical end effector, with the term "proximal" referring to the location of an element closer to the surgeon or other operator and the term "distal" referring to the location of an element closer to the surgical end effector of the surgical instrument and further away from the surgeon or other operator.

[0010] I. Exemplary Devices for Subretinal Administration of Therapeutic Agents 1 illustrates an exemplary instrument (10) configured for use in a procedure for subretinal administration of a therapeutic agent to a patient's eye via a suprachoroidal approach. The instrument (10) includes a body (20) and a flexible cannula (50) extending distally from the body (20). The cannula (50) in this example has a generally rectangular cross-section, although any other suitable cross-sectional profile (e.g., oval, etc.) may be used. The cannula (50) is generally configured to support a needle (100) that is slidable within the cannula (50), as described in more detail below.

[0011] In this example, cannula 50 comprises a flexible material, such as polyether block amide (PEBA), which may be manufactured under the trade name PEBAX. Of course, any other suitable material or combination of materials may be used. Also, in this example, cannula 50 has cross-sectional profile dimensions of approximately 2.0 mm by 0.8 mm and a length of approximately 80 mm. Alternatively, any other suitable dimensions may be used. As described in more detail below, cannula 50 is flexible enough to conform to the unique anatomy and contours of a patient's eye, yet has sufficient column strength to allow cannula 50 to be advanced between the sclera and choroid of a patient's eye without bending. By way of example only, cannula (50) may be constructed and operable in accordance with at least a portion of the teachings of U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosure of which is incorporated herein by reference.

[0012] As seen in FIGS. 2-3B and 6, the cannula (50) includes a body (52), a closed distal end (54), and a lateral opening (56) located proximal to the distal end (54). In this example, the distal end (54) has a rounded configuration. It should be understood that the distal end (54) may have any suitable type of curvature. It should also be understood that the distal end (54) may have any other suitable type of configuration (e.g., beveled). In this example, the distal end (54) is configured to provide a separation between the scleral and choroidal layers, allowing the cannula (50) to advance between such layers while avoiding trauma to the scleral or choroidal layers. Additionally, in this example, the region of the body (52) defining the lateral opening (56) is beveled, as best seen in FIGS. 3A-3B. Alternatively, the edges of the side opening (56) may have any other suitable configuration.

[0013] As best seen in Figures 3A-3B, needle guide 60 is disposed within the hollow interior of cannula 50. By way of example only, needle guide 60 may be secured within cannula 50 by a press fit or interference fit, by adhesive, by a mechanical locking mechanism, and / or in any other suitable manner. Needle guide 60 includes a curved distal end 62 that connects to side opening 56 of cannula 50, with lumen 64 of needle guide 60 distally terminating at side opening 56. The portion of needle guide 60 proximal to distal end 62 is substantially straight. Needle guide 60 may be formed of plastic, stainless steel, and / or any other suitable biocompatible material.

[0014] The needle (100) of this example has a sharpened distal tip (102) and defines a lumen (104). The distal tip (102) of this example has a lancet configuration. In some other variations, the distal tip (102) has a tri-bevel configuration or any other configuration, as described in U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosure of which is incorporated herein by reference. Still other suitable forms that the distal tip (102) may take will be apparent to those skilled in the art in light of the teachings herein. The needle (100) of this example comprises a stainless steel hypodermic needle sized to deliver a therapeutic agent, as described in more detail below, yet small enough to minimize accidental trauma as the needle (100) penetrates the tissue structures of a patient's eye. Although stainless steel is used in this example, it should be understood that any other suitable material may be used, including but not limited to Nitinol.

[0015] By way of example only, needle 100 may be 35 gauge with an inner diameter of 100 μm, although other suitable sizes can be used. For example, the outer diameter of needle 100 may fall within the range of 27 gauge to 45 gauge; or, more specifically, within the range of 30 gauge to 42 gauge; or, more specifically, within the range of 32 gauge to 39 gauge. As another merely illustrative example, the inner diameter of needle 100 may fall within the range of about 50 μm to about 200 μm; or, more specifically, within the range of about 50 μm to about 150 μm; or, more specifically, within the range of about 75 μm to about 125 μm.

[0016] The needle 100 is slidably disposed within the lumen 64 of the needle guide 60. The needle guide 60 is generally configured to guide the needle 100 upward through the side opening 56 of the cannula 50 along an exit axis EA that is oriented obliquely relative to the longitudinal axis LA of the cannula 50. This is illustrated in the sequence depicted in Figures 3A-3B, where Figure 3A shows the needle 100 in a proximal position (the distal tip 102 of the needle 100 is fully contained within the lumen 64 of the needle guide 60); and Figure 3B shows the needle 100 in a distal position (the distal tip 102 of the needle 100 is outside the needle guide 60). While the needle 100 is flexible, the needle 100 in this example is resiliently biased to a straight configuration. Thus, as shown in Figure 3B, the portion of the needle (100) that extends outside the cannula (50) and needle guide (60) is substantially straight and extends along the exit axis (EA). In particular, at least a substantial length of the portion of the needle (100) that extends outside the cannula (50) and needle guide (60) is coaxially aligned with the exit axis (EA).

[0017] It should be understood that the depiction of the exit axis (EA) in Figures 3A-3B may be somewhat exaggerated for illustrative purposes only. In some variations, the curved distal end (62) is configured to direct the needle (100) along an exit axis (EA) extending distally from the cannula (50) at an angle of about 7° to about 9° relative to the longitudinal axis (LA) of the cannula (50). It should be understood that such an angle may be desirable to ensure needle penetration into the choroid and to deflect the needle (100) in a direction that minimizes the possibility of the needle (100) continuing below the choroid through the suprachoroidal space (as opposed to penetrating the choroid) and the possibility of retinal perforation. Further by way of example only, curved distal portion (88) may cause needle (100) to exit cannula (50) along an exit axis (EA) oriented at an angle within a range of about 5° to about 30° relative to the longitudinal axis (LA) of cannula (50); or, more specifically, within a range of about 5° to about 20° relative to the longitudinal axis (LA) of cannula (50); or, more specifically, within a range of about 5° to about 10° relative to the longitudinal axis (LA) of cannula (50).

[0018] As shown in FIG. 1 , the instrument 10 of this example further includes an actuation knob 26 located at the proximal end of the body 20. The actuation knob 26 is rotatable relative to the body 20 to selectively translate the needle 100 longitudinally relative to the cannula 50. In particular, the actuation knob 26 is rotatable in a first angular direction to drive the needle 100 distally relative to the cannula 50 and in a second angular direction to drive the needle 100 proximally relative to the cannula 50. By way of example only, the instrument 10 may provide such functionality through the knob 26 in accordance with at least some of the teachings of U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosure of which is incorporated herein by reference. Alternatively, any other suitable type of actuation feature may be used to drive needle (100) longitudinally relative to cannula (50).

[0019] In this embodiment, knob 26 is rotatable through a full range of motion, which corresponds to advancing needle 100 to a position relative to cannula 50 to a predetermined penetration amount within the patient's eye. In other words, instrument 10 is configured so that the operator rotates knob 26 to properly position needle 100 within the patient's eye until knob 26 can no longer rotate or until knob 26 begins to slip or "freewheel" in the clutch assembly. In some embodiments, the predetermined advancement of needle 100 relative to cannula 50 is between about 0.25 mm and about 10 mm; or, more specifically, between about 0.1 mm and about 10 mm; or, more specifically, between about 2 mm and about 6 mm; or, even more specifically, up to about 4 mm.

[0020] Additionally or alternatively, instrument 10 may include certain tactile feedback features that indicate to the operator when needle 100 has advanced a certain predetermined distance relative to cannula 50. Thus, the operator can determine the desired penetration depth of needle 100 into the patient's eye based on direct visualization of markings on the instrument and / or based on tactile feedback from instrument 10. Of course, such tactile feedback features can be combined with this embodiment, as would be apparent to one of ordinary skill in the art in view of the teachings herein.

[0021] As also shown in FIG. 1 , a pair of supply tubes (30, 40) extend proximally from the actuator knob (26). In this example, the first supply tube (30) is configured to couple to a source of bleb fluid (340) (e.g., BSS); the second supply tube (40) is configured to couple to a source of therapeutic agent (341). It should be understood that each fluid supply tube (30, 40) may include conventional luer features and / or other structures that enable the fluid supply tubes (30, 40) to be coupled to their respective fluid sources. The fluid supply tubes (30, 40) lead to a valve assembly that includes an actuator arm (24). The actuator arm (24) is pivotable to selectively change the state of the valve assembly. Based on the pivotal position of the actuation arm (24), the valve assembly is operable to selectively clamp or otherwise open / close the supply of fluid from the fluid supply tubes (30, 40) to the lumen (104) of the needle (100). Thus, the actuation arm (24) is operable to selectively control the delivery of the bleb fluid (340) and the therapeutic agent (341) through the needle (100). By way of example only, the valve assembly may be configured and operable in accordance with at least a portion of the teachings of U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosure of which is incorporated herein by reference. Other suitable features and configurations that may be used to control fluid delivery through the needle (100) will be apparent to those skilled in the art in view of the teachings herein.

[0022] It should be understood that the features and operability of device 10 may be varied in many ways. In addition, device 10 may be adapted for use in a variety of applications, including those described in U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosures of which are incorporated herein by reference; U.S. Patent Application Publication No. 2015 / 0351958, published December 10, 2015, entitled "Therapeutic Agent Delivery Device with Convergent Lumen," the disclosures of which are incorporated herein by reference; U.S. Patent Application Publication No. 2015 / 0351959, published December 10, 2015, entitled "Sub-Retinal Tangential Needle Catheter Guide and Introducer," the disclosures of which are incorporated herein by reference; and U.S. Patent Application Publication No. 2015 / 0351959, published December 10, 2015, entitled "Method and Apparatus for Sensing Position Between Layers of an No. 2016 / 0074212, published March 17, 2016, entitled "Motorized Suprachoroidal Injection of Therapeutic Agent," the disclosure of which is incorporated herein by reference; U.S. Patent Application Publication No. 2016 / 0074217, published March 17, 2016, entitled "Therapeutic Agent Delivery Device with Advanceable Cannula and Needle," the disclosure of which is incorporated herein by reference; and / or U.S. Patent Application Publication No. 2016 / 0081849, published March 24, 2016, entitled "Therapeutic Agent Delivery Device," the disclosure of which is incorporated herein by reference. Other suitable modifications will be apparent to those skilled in the art in view of the teachings herein.

[0023] II. Exemplary Procedures for Subretinal Administration of Therapeutic Agents 4A-5C illustrate an exemplary procedure for subretinal delivery of a therapeutic agent via a suprachoroidal approach using the previously described device (10). By way of example only, the methods described herein can be used to treat macular degeneration and / or other ocular conditions. While the procedures described herein are discussed in the context of treating age-related macular degeneration, it should be understood that no such limitation is intended or implied. For example, and by way of example only, in some alternative procedures, the same techniques described herein can be used to treat retinitis pigmentosa, diabetic retinopathy, and / or other ocular conditions. Furthermore, it should be understood that the procedures described herein can be used to treat either dry or wet age-related macular degeneration.

[0024] In this example, the procedure begins with the operator immobilizing the tissue (e.g., eyelid) surrounding the patient's eye (301) using a speculum and / or any other instrument suitable for immobilization. While fixation is described herein with respect to the tissue surrounding the eye (301), it should be understood that the eye (301) itself may remain freely movable. Once the tissue surrounding the eye (301) is immobilized, an eye chandelier port (314) is inserted into the eye (301) as shown in FIG. 4A to provide endoscopic illumination when viewing the interior of the eye (301) through the pupil. In this example, the eye chandelier port (314) is positioned in the inferior medial quadrant so that a superior temporal quadrant sclerotomy can be performed. The ophthalmic chandelier port (314) is positioned to direct light into the interior of the eye (301) to illuminate at least a portion of the retina (e.g., including at least a portion of the macula), as will be appreciated, such illumination corresponds to the region of the eye (301) targeted for therapeutic agent delivery.

[0025] In this example, only the chandelier port (314) has been inserted at the stage shown in FIG. 4A ; the optical fiber (315) has not yet been inserted into the port (314). In some other variations, the optical fiber (315) may be inserted into the chandelier port (314) at this stage. In either case, a microscope may optionally be used to visually examine the eye and confirm proper positioning of the ophthalmic chandelier port (314) relative to the target site. While FIG. 4A shows a particular positioning of the ophthalmic chandelier port (314), it should be understood that the ophthalmic chandelier port (314) may have any other positioning, as will be apparent to those skilled in the art in view of the teachings herein.

[0026] Once the ophthalmic chandelier port (314) is positioned, the sclera (304) may be accessed by dissecting the conjunctiva by making an incision in the conjunctiva flap and retracting the flap. After such dissection is completed, the exposed surface (305) of the sclera (304) may optionally be blanched using a cautery tool to minimize bleeding. Once the conjunctival dissection is complete, the exposed surface (305) of the sclera (304) may optionally be dried using a WECK-CEL or other suitable absorbent device. The eye (301) may then be marked using a template, as described in U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agents," the disclosure of which is incorporated herein by reference. Using the visual guide created with the template, the operator can then attach the suture loop assembly (332) and perform a sclerotomy using a conventional scalpel (313) or other suitable cutting instrument, as shown in FIG. 4B. The sclerotomy procedure involves making a small incision through the sclera (304) of the eye (301). The sclerotomy is performed with particular care to avoid penetrating the choroid (306). The sclerotomy thus provides access to the space between the sclera (304) and the choroid (306). Once the incision is made in the eye (301), blunt dissection can optionally be performed to locally separate the sclera (304) from the choroid (306). Such an incision can be performed using a small, blunt, elongated instrument, as will be apparent to those skilled in the art in view of the teachings herein.

[0027] Once the sclerotomy procedure has been performed, the operator may insert the cannula (50) of the instrument (10) through the incision (316) and into the space between the sclera (304) and the choroid (306). As can be seen in FIG. 4C , the cannula (50) is guided through the suture loop assembly (332) and into the incision. The suture loop assembly (332) may stabilize the cannula (50) during insertion. Additionally, the suture loop assembly (332) maintains the cannula (50) in a generally tangential orientation relative to the incision. This tangential orientation may reduce trauma as the cannula (50) is guided through the incision. As the cannula (50) is inserted through the suture loop assembly (332) and into the incision, the operator may use forceps or other instruments to further guide the cannula (50) along an atraumatic path. Of course, the use of forceps or other instruments is merely optional and may be omitted in some embodiments.

[0028] Although not shown, it should be understood that in some embodiments, the cannula 50 may include one or more markers on the surface of the cannula 50 to indicate various insertion depths. While merely optional, such markers may be desirable to assist the operator in identifying the appropriate insertion depth as the cannula 50 is guided along an atraumatic pathway. For example, the operator may visually observe the location of such markers relative to the suture loop assembly 332 and / or relative to the incision in the sclera 304 as an indication of the depth to which the cannula 50 is inserted into the eye 301. By way of example only, one such marker may correspond to an insertion depth of approximately 6 mm of the cannula 50.

[0029] As shown in FIG. 4D , once the cannula (50) is at least partially inserted into the eye (301), the operator may insert the optical fiber (315) into the ophthalmic chandelier port (314) if it is not already inserted at this stage. Once the ophthalmic chandelier port (314) is in place and assembled with the optical fiber (315), the operator may activate the ophthalmic chandelier port (314) by directing light through the optical fiber (315) to provide illumination of the eye (301), thereby visualizing the interior of the eye (301). Further adjustments to the positioning of the cannula (50) may optionally be made at this point to ensure proper positioning relative to the geographic atrophy area of ​​the retina (308). In some cases, the operator may wish to rotate the eye (301), such as by pulling the suture loop assembly (332), to orient the pupil of the eye (301) toward the operator to optimize visualization of the interior of the eye (301) through the pupil.

[0030] 4C-4D show the cannula 50 as it is guided between the sclera 304 and choroid 306 to the therapeutic agent delivery site. In this example, the delivery site corresponds to a generally posterior region of the eye 301 adjacent to the area of ​​geographic atrophy of the retina 308. Specifically, the delivery site in this example is superior to the macula, in the potential space between the neurosensory retina and the retinal pigment epithelium. By way of example only, the operator may rely on direct visualization through a microscope performed through the pupil of the eye 301 as the cannula 50 is advanced through the range of motion shown in FIGS. 4C-4D , with illumination provided through the fiber 315 and port 314. The cannula 50 may be at least partially visible through the retina 308 and choroid 306 of the eye 301. Visual tracking can be enhanced with variations that use fiber optics to emit visible light through the distal end of the cannula (50).

[0031] Once the cannula 50 is advanced to the delivery site, as shown in FIG. 4D , the operator can advance the needle 100 of the instrument 10 as previously described by actuating the knob 26. As can be seen in FIGS. 4E and 5A , the needle 100 is advanced relative to the cannula 50 so that the needle 100 penetrates the choroid 306 without penetrating the retina 308. Just before penetrating the choroid 306, the needle 100 may appear under direct visualization as "tenting" the surface of the choroid 306. In other words, the needle 100 may deform the choroid 306 by pushing up against it, creating an appearance similar to a tent pole deforming the roof of the tent. This visual phenomenon may be used by the operator to determine whether the choroid 306 is about to be penetrated and to identify any final penetration locations. The particular amount of advancement of the needle (100) sufficient to begin to "tent" and thereafter penetrate the choroid (306) may be any suitable amount, as may be determined by several factors, such as, but not limited to, the overall patient anatomy, the local patient anatomy, operator preference, and / or other factors. As previously mentioned, merely exemplary ranges of advancement of the needle (100) may be from about 0.25 mm to about 10 mm, or, more specifically, from about 2 mm to about 6 mm.

[0032] In this example, after the operator confirms that the needle 100 has been properly advanced by visualizing the tenting effect described above, the operator injects a balanced salt solution (BSS) or other similar solution as the needle 100 is advanced relative to the cannula 50. Such BSS may form a leading bleb 340 in front of the needle 100 as it advances through the choroid 306. The leading bleb 340 may be desirable for two reasons. First, as shown in FIGS. 4F and 5B, the leading bleb 340 may provide the operator with an additional visual indicator of when the needle 100 is properly positioned at the delivery site. Second, the leading bleb 340 may provide a barrier between the needle 100 and the retina 308 once the needle 100 penetrates the choroid 306. Such a barrier can push the retinal wall outward, thereby minimizing the risk of retinal perforation as the needle 100 advances to the delivery site. In some variations, a foot pedal is activated to push the leading bleb 340 from the needle 100. Alternatively, other suitable features that can be used to push the leading bleb 340 from the needle 100 will be apparent to those skilled in the art in view of the teachings herein.

[0033] Once the operator visualizes the leading bleb (340), the operator may discontinue injection of the BSS, leaving behind a pocket of fluid as can be seen in FIGS. 4F and 5B. A therapeutic agent (341) may then be injected by actuating a syringe or other fluid delivery device as described in the various references cited herein. The particular therapeutic agent (341) delivered may be any suitable therapeutic agent configured to treat an ocular condition. Some merely exemplary suitable therapeutic agents will be apparent to those skilled in the art in view of the teachings herein, and may include, but are not necessarily limited to, drugs having smaller or larger molecules, therapeutic cell solutions, certain gene therapy solutions, tissue plasminogen activator, and / or any other suitable therapeutic agent. By way of example only, therapeutic agent (341) may be provided in accordance with at least some of the teachings of U.S. Patent No. 7,413,734, issued August 19, 2008, entitled "Treatment of Retinitis Pigmentosa with Human Umbilical Cord Cells," the disclosure of which is incorporated herein by reference. In addition to, or instead of being used to deliver therapeutic agent (341), instrument (10) and its variants may be used to effect drainage and / or perform other procedures.

[0034] In this example, the amount of therapeutic agent (341) ultimately delivered to the delivery site is approximately 50 μL, although any other suitable amount may be delivered. In some variations, a foot pedal is activated to force the agent (341) out of the needle (100). Alternatively, other suitable features that may be used to force the agent (341) out of the needle (100) will be apparent to those skilled in the art in light of the teachings herein. Delivery of the therapeutic agent (341) can be visualized by the expansion of a pocket of fluid, as can be seen in FIGS. 4G and 5C. As shown, the therapeutic agent (341) essentially mixes with the fluid of the leading bleb (340) as the therapeutic agent (341) is injected into the surprachoroidal, subretinal space.

[0035] Once delivery is complete, the needle (100) may be retracted by rotating the knob (26) in the opposite direction to that used to advance the needle (100); the cannula (50) may then be withdrawn from the eye (301). It should be appreciated that due to the size of the needle (100), the site where the needle (100) penetrated through the choroid (306) is self-sealing, and no further steps need to be taken to seal the delivery site through the choroid (306). The suture loop assembly (332) and chandelier (314) may be removed, and the incision in the sclera (304) may be closed using any suitable conventional technique.

[0036] As previously mentioned, the procedures described above may be performed to treat patients with macular degeneration. In some such cases, the therapeutic agent (341) delivered by the needle (100) may include cells obtained from the postpartum umbilicus and placenta. As previously mentioned, by way of example only, the therapeutic agent (341) may be provided in accordance with at least some of the teachings of U.S. Patent No. 7,413,734, issued August 19, 2008, entitled "Treatment of Retinitis Pigmentosa with Human Umbilical Cord Cells," the disclosure of which is incorporated herein by reference. Alternatively, the needle (100) may be used to deliver any other suitable substance or substances in addition to or in place of those described in U.S. Patent No. 7,413,734 and / or elsewhere herein. By way of example only, the therapeutic agent (341) may include various types of drugs, including, but not limited to, small molecule, large molecule, cell, and / or gene therapy. It should also be understood that macular degeneration is merely an illustrative example of a condition that may be treated through the procedures described herein. Other biological conditions that may be addressed using the devices and procedures described herein will be apparent to those skilled in the art.

[0037] The foregoing procedures may be performed using techniques described in U.S. Patent Application Publication No. 2015 / 0223977, published August 13, 2015, entitled "Method and Apparatus for Subretinal Administration of Therapeutic Agent," the disclosures of which are incorporated herein by reference; U.S. Patent Application Publication No. 2015 / 0351958, published December 10, 2015, entitled "Therapeutic Agent Delivery Device with Convergent Lumen," the disclosures of which are incorporated herein by reference; U.S. Patent Application Publication No. 2015 / 0351959, published December 10, 2015, entitled "Sub-Retinal Tangential Needle Catheter Guide and Introducer," the disclosures of which are incorporated herein by reference; and U.S. Patent Application Publication No. 2015 / 0351959, published December 10, 2015, entitled "Method and Apparatus for Sensing Position Between Layers of an It should also be understood that the methods and techniques described herein may be performed in accordance with any of the teachings of U.S. Patent Application Publication No. 2016 / 0074212, published on March 17, 2016, entitled "Motorized Suprachoroidal Injection of Therapeutic Agents," the disclosure of which is incorporated herein by reference; U.S. Patent Application Publication No. 2016 / 0074217, published on March 17, 2016, entitled "Therapeutic Agent Delivery Device with Advanceable Cannula and Needle," the disclosure of which is incorporated herein by reference; U.S. Patent Application Publication No. 2016 / 0074211, published on March 17, 2016, entitled "Therapeutic Agent Delivery Device with Advanceable Cannula and Needle," the disclosure of which is incorporated herein by reference; and / or U.S. Patent Application Publication No. 2016 / 0081849, published on March 24, 2016, entitled "Therapeutic Agent Delivery Device," the disclosure of which is incorporated herein by reference.

[0038] III. Exemplary Injector System with Remote Control In some variations of the procedures described above with reference to FIGS. 4A-4G and 5A-5C, the patient may be awake and under local anesthesia. In such cases, there is a risk of patient movement. Such patient movement while the cannula 50 is positioned within the eye 301 may cause eye damage. Additionally, operation of the instrument 10 requires manual manipulation of the actuator arm 24 and actuator knob 26. Such manually operable features may present a risk of unintended movement of the cannula 50 within the eye 301. Additionally, consistently achieving accurate administration of the bleb fluid 340 and therapeutic agent 341 may be problematic. Therefore, it may be desirable to mitigate risks related to patient movement, reduce the risk of unintended movement of components positioned within the eye 301, and increase the consistency of the accuracy of administration of the bleb fluid 340 and therapeutic agent 341.

[0039] A. Overview FIG. 6 illustrates an exemplary system 400 that may be used to deliver bleb fluid 340 and therapeutic agent 341 into a patient's eye 301. The system 400 of this example includes a control module 500, an injector driver assembly 600, and an injector assembly 700. A syringe actuation cassette 550 is disposed within the control module 500 and is coupled to the injector driver assembly 600 via a tubing set 420. The syringe actuation cassette 550 is also coupled to a balanced salt solution (BSS) bottle 410 via a conduit 412. The injector assembly 700 is coupled to the injector driver assembly 600 via a tubing and cable assembly 690. Each of these components is described in further detail below.

[0040] As shown in FIG. 7 , the disposable components of system (400) may be provided in sterile kit form. These components include syringe actuation cassette (550), conduit (412) with integral spike (414), tubing set (420), injector driver assembly (600), tubing and cable assembly (690), and injector assembly (700). As shown, syringe actuation cassette (550), conduit (412) with integral spike (414), tubing set (420), injector driver assembly (600), tubing and cable assembly (690), and injector assembly (700) may all be pre-connected together in the sterile kit. The sterile kit of this example also includes marking device (430), magnetic pad (430), syringe (570), and syringe adapter (580). The marking instrument (430) is operable to mark a location on the eye (301), such as a location for placement of the suture loop assembly (332). By way of example only, the marking instrument (430) may be constructed and operable in accordance with the teachings of U.S. Patent Application Publication No. 2015 / 0223977, the disclosure of which is incorporated herein by reference. As another merely illustrative example, the marking instrument (430) may be constructed and operable in accordance with the teachings of U.S. Patent Application No. [Attorney Docket No. END8062USNP.0648021], filed on even date herewith, entitled "Guide Apparatus for Tangential Entry into Suprachoroidal Space," the disclosure of which is incorporated herein by reference. Other components of the sterile kit shown in FIG. 7 are described in more detail below. As also shown in FIG. 7, another sterile kit may include a syringe (570) and a syringe adapter (580).

[0041] FIG. 8 shows the components of system 400 positioned relative to a patient. In this embodiment, a drape 452 is draped over the patient, with an opening 454 formed in the drape 452 adjacent to the patient's eye 301. A speculum 440 is used to hold the eye 301 open. A fixture 450 is positioned adjacent to the eye 301. The fixture 450 may be used to secure instrumentation, such as a viewing scope, to the patient. A magnetic pad 460 is adhered to the drape 452 adjacent to the eye 301 and near the opening 454. An injector assembly 700 is placed on the magnetic pad 460 and removably secured thereto via magnetic attraction, as described in more detail below. The injector assembly (700) is oriented so that the flexible cannula (702) of the injector assembly (700) can be inserted into the eye (301). The injector driver assembly (600) is removably secured to the wrist rest (456) via an arm (606). The injector driver assembly (600) is positioned sufficiently close to the injector assembly (700) to provide some slack in the tubing and cable assembly (690). Although not shown in FIG. 8 , the injector driver assembly (600) is coupled to the control module (500) via the syringe actuation cassette (550) and the tubing set (420).

[0042] B. Exemplary Control Modules and Methods of Use As shown in Figures 9A-9B, the control module (500) of this example includes a base (502) and a cover (504). The cover (504) is configured to pivot relative to the base (502) between an open position (Figure 9B) and a closed position (Figure 9A). The cover (504) includes a display area (506) operable to display information in the form of images, numbers, text, and / or other information. As shown in Figure 9B, the base (502) includes a defrosting chamber (508), a cassette storage area (510), and a cassette actuator (510).

[0043] The thawing chamber (508) includes components operable to thaw (e.g., using heated air) frozen therapeutic substance vial assemblies (590). A variety of suitable components and devices that may be used to provide such thawing functionality will be apparent to those skilled in the art in view of the teachings herein.

[0044] The cassette receptacle 510 is configured to removably receive a syringe actuation cassette 550. The cassette actuator 512 is configured to interact with complementary features on the syringe actuation cassette 550 to selectively control the delivery of bleb fluid 340 from the bottle 410 to the tubing set 420. By way of example only, the syringe actuation cassette 550 may include a pump actuated by the cassette actuator 512 to force the bleb fluid 340 from the bottle 410 to the tubing set 420. As another merely illustrative example, the cassette 550 may be modified to receive a second syringe containing the bleb fluid 340, and the cassette actuator 512 may be configured to actuate features on the cassette 550 to expel the bleb fluid 340 from the syringe containing the bleb fluid 340. Other suitable ways in which the cassette actuator (512) and syringe actuation cassette (550) may be configured to cooperate to provide controlled delivery of bleb fluid (340) through the tubing set (420) will be apparent to those skilled in the art in light of the teachings herein.

[0045] Cassette actuator (512) is further configured to interact with complementary features of syringe actuation cassette (550) to selectively control delivery of therapeutic agent (341) from syringe (570) to tubing set (420). By way of example only, syringe actuation cassette (550) or control module (500) may include a lead screw operable to actuate plunger (574), thereby forcing therapeutic agent (341) from syringe (570) into tubing set (420). Other suitable components and devices that may be used to provide such fluid delivery control functionality will be apparent to those skilled in the art in view of the teachings herein.

[0046] Cassette actuator 512 in this example further includes a coupling feature operable to receive data from electrical cable 426 once syringe actuation cassette 550 is fully seated within cassette location 510. Examples of such data are described in further detail below. It should also be appreciated that control module 500 may provide power or signals through electrical cable 426.

[0047] In an exemplary method of use, control module (500) initially includes cover (504) in a closed position, as shown in FIG. 9A. The operator then opens cover (504), as shown in FIG. 9B. With cover (504) in the open position, the operator inserts therapeutic substance vial assembly (590) into thawing chamber (508), as shown in FIG. 9C. The therapeutic substance vial assembly (590) includes case (592) (FIG. 9E) that houses vial (594) (FIG. 9E) containing a volume of frozen therapeutic agent (341).

[0048] The operator then closes the cover (504), as shown in FIG. 9D. This closure of the cover (504) initiates a thawing sequence in the thawing chamber (508) to thaw the therapeutic agent (341) contained in the therapeutic agent vial assembly (590). By way of example only, the control module (500) may include an integrated heater-air thawing mechanism for thawing cryogenically frozen cells in the therapeutic agent (341) contained in the therapeutic agent vial assembly (590). An infrared temperature sensor (or other type of temperature sensor) may measure the exterior of the therapeutic agent vial assembly (590) and ensure that the temperature never exceeds 37°C to protect the cells in the therapeutic agent (341). During the thawing sequence, the display area (506) displays the time remaining until the thawing sequence is complete. Once thawing is complete, the operator opens the cover (504) and removes the therapeutic agent vial assembly (590) from the thawing chamber (508).

[0049] Next, the operator places the thawed therapeutic substance vial assembly (590) into the body (582) of the syringe adapter (580), as shown in FIG. 9E. The body (582) has a configuration complementary to that of the case (592), allowing the therapeutic substance vial assembly (590) to be freely inserted into the body (582). As shown in FIG. 9E, the syringe adapter (580) further includes an integral needle (584) rigidly secured to the body (582). The needle (584) is positioned such that the needle (584) pierces the septum of the vial (594) when the substance vial assembly (590) is fully inserted into the body (582). Needle (584) is also positioned and firmly secured relative to body (582) so that needle (584) does not contact the interior surface of vial (594), thereby eliminating the risk of needle (584) inadvertently scraping the sidewall of vial (594) and generating particles.

[0050] As also shown in FIG. 9E, the syringe (570) of this example includes a body (572) with a plunger (574) and a distal fitting (576). The plunger (574) is configured to reciprocate relative to the body (572) to selectively draw fluid into or expel fluid from the body (572). The distal fitting (576) is configured to removably couple to the proximal end of the body (582). When the distal fitting (576) is coupled to the proximal end of the body (582), the distal fitting (576) is in fluid communication with the needle (584), thereby placing the body (572) in fluid communication with the needle (584).

[0051] 9F shows the substance vial assembly (590) fully installed within the syringe adapter (580). It should be appreciated that the complementary configuration of the vial assembly (590) and the syringe adapter (580) may provide self-centering of the substance vial assembly (590) within the syringe adapter (580) and depth control of the needle (584) within the vial (594) when the substance vial assembly (590) reaches its fully installed position. With the substance vial assembly (590) fully installed within the syringe adapter (580), the operator retracts the plunger (574) proximally while holding the other components stationary. This draws the therapeutic agent (341) from the vial (594) through the needle (584) and distal fitting (576) and into the body (572) of the syringe (570).

[0052] After the operator transfers the appropriate amount of therapeutic agent (341) from the vial (594) into the body (572) of the syringe (570), the operator positions the syringe (570) in the syringe receiving receptacle (552) of the syringe actuation cassette (550), as shown in FIG. 9G. The distal fitting (576) is oriented toward the bottom portion of the syringe receiving receptacle (552). As also shown in FIG. 9G, the tubing set (420) and the conduit (412) extend from the bottom portion of the syringe actuation cassette (550). As described in further detail below, the tubing set (420) houses a first conduit (422) configured to deliver the bleb fluid (340), a second conduit (424) configured to deliver the therapeutic agent (341), and an electrical cable (426) configured to deliver power and / or data signals.

[0053] Before or after installing syringe (570) into syringe actuation cassette (550), the operator inserts spike (414) of conduit (412) into bottle (410), as shown in FIG. 9H, thereby providing a path for delivering bleb fluid (340) from bottle (410) to syringe actuation cassette (550).

[0054] With syringe 570 and bottle 410 coupled to syringe actuation cassette 550, the operator positions syringe actuation cassette 550 relative to cassette receptacle 510, as shown in Figure 9I. The operator then fully installs syringe actuation cassette 550 into cassette receptacle 510, as shown in Figure 9J. This couples cassette actuator 512 with complementary features on syringe actuation cassette 550, as previously described.

[0055] The operator then closes cover (504), as shown in FIG. 9K, to initiate the priming sequence. In some variations, priming begins automatically when cover (504) is closed. In some other variations, priming does not begin until the operator activates some type of user input feature after closing cover (504). In either case, cover (504) includes features that accommodate conduits (412) and tubing set (420) without pinching off or otherwise impeding fluid flow through conduits (412, 422, 424). The priming sequence removes air from conduits (412, 422, 424) and ensures that the entire length of each conduit (412, 422, 424) is filled with the corresponding fluid. In some cases, this priming sequence, in addition to priming first conduit (422) with bleb fluid (340), further includes priming needle (708) and needle actuator (716) of injector assembly (700) with bleb fluid (340). When therapeutic agent (341) is primed through second conduit (424), control module (500) may ensure that such priming occurs at a relatively slow flow rate to minimize stress on cells contained within therapeutic agent (341).

[0056] During the priming sequence, display area 506 may display an indication to the operator that the priming sequence is in progress. Additionally, display area 506 may display the time remaining in the priming sequence. After the priming sequence is complete, display area 506 may display an indication to the operator that control module 500 is ready for use, as shown in FIG. 9L.

[0057] In some variations, the control module (500) is operable to sense the presence of an occlusion in at least one of the conduits (412, 422, 424). Various suitable methods by which an occlusion may be detected will be apparent to those skilled in the art in view of the teachings herein. If an occlusion is detected, the control module (400) may automatically alert the operator via the display area (506).

[0058] C. Exemplary Magnetic Pad As previously mentioned, the system 400 of this embodiment includes a magnetic pad 460. The magnetic pad 460 may be attached to the drape 452 via a pressure-sensitive adhesive. For example, the magnetic pad 460 may include a peel-off cover positioned over the adhesive on the underside. An operator may then peel off the cover to expose the adhesive and then press the magnetic pad 460 against the drape 452 to adhere the magnetic pad 460 to the drape. During use, the magnetic pad 460 is positioned on the drape 452 over the patient's forehead. In this embodiment, the magnetic pad 460 is flexible to a certain extent, allowing the magnetic pad 460 to at least partially conform to the curvature of the patient's forehead. By way of example only, the magnetic pad 460 may be formed at least in part from silicone.

[0059] As also previously mentioned, the injector assembly 700 rests on the magnetic pad 460 and is removably secured thereto via magnetic attraction. This allows the injector assembly 700 to be easily repositioned on and removed from the magnetic pad 460. As described in further detail below, the injector assembly 700 includes a magnet 706 that exerts a magnetic attraction on the magnetic pad 460. In some variations, the magnetic pad 460 also includes an array of magnetic elements that exert a magnetic attraction with the magnet 706. In some other variations, the magnetic pad 460 includes one or more ferrous elements (e.g., ferrous metal filings embedded in the pad material, a single thin metal sheet embedded in the pad material, etc.) that exert a magnetic attraction with the magnet 706. A variety of suitable features and configurations that may be incorporated into magnetic pad (460) to provide magnetic attraction with magnet (706) will be apparent to those skilled in the art in view of the teachings herein. As yet another merely exemplary variant, other features may be used to provide a detachable connection between pad (460) and injector assembly (700), including, but not limited to, hook-and-loop fasteners, adhesives, complementary press-fit raised textures and grip patterns, and the like.

[0060] Figures 10-12 illustrate various alternative configurations that the magnetic pad (460) may take. In particular, Figure 10 illustrates a magnetic pad (470) having a generally arcuate shape. This arcuate shape includes a recessed area (472) that may be positioned near the patient's eye (301). Figure 11 illustrates a magnetic pad (480) having an elliptical or flattened oval shape. Figure 12 illustrates a magnetic pad (490) having a generally rectangular shape with a recessed side (492) that may be positioned near the patient's eye (301). Other suitable configurations that the magnetic pad (460) may take will be apparent to those skilled in the art in view of the teachings herein.

[0061] D. Exemplary Injector Assembly with Remote Tethering Control Figure 13 shows the injector driver assembly (600) coupled to the injector assembly (700) via a tubing and cable assembly (690). As shown in Figure 13, the conduits (422, 424) and electrical cable enter the proximal end of the injector driver assembly (600) as part of the tubing set (420). The conduits (422, 424) pass through the injector driver assembly (600) and exit the distal end of the injector driver assembly (600) as part of the tubing and cable assembly (690). The conduits (422, 424) enter the proximal end of the injector assembly (700) as part of the tubing and cable assembly (690). The tube and cable assembly (690) also includes a push-pull cable (692), which is operable to transmit longitudinal motion from the injector driver assembly (600) to the injector assembly (700), as described in further detail below. The tube and cable assembly (690) also includes an outer sheath (694). The outer sheath (694) is configured to house the conduits (422, 424) and the push-pull cable (692). The outer sheath (694) is also configured to serve as a longitudinal mechanical ground for the push-pull cable (692), which translates relative to the outer sheath (694).

[0062] 1. Exemplary Injector Assembly 14-18 illustrate the injector assembly 700 and its components in further detail. As shown, the injector assembly 700 of this example includes a cannula 702, a pair of housing halves 704, and a needle 708 slidably disposed within the housing half 704. The cannula 702 may be configured and operable similarly to the previously described cannula 50, and the needle 708 may be configured and operable similarly to the previously described needle 100. A needle actuator 710 and a magnet 706 are captured within the housing half 704. When the injector assembly 700 is fully assembled, the housing half 704 is configured to hold the magnet 706 in a stationary position and allow the needle actuator 710 to translate distally and proximally within the housing half 704. In particular, as best seen in Figures 15A-15B, housing half (704) includes boss (705) configured to guide and laterally support needle actuator (710) as it translates between a proximal position (Figure 15A) and a distal position (Figure 15B).

[0063] As best seen in FIGS. 16-17, the needle actuator (710) includes a proximal housing (740), an intermediate housing (730), and a distal housing (720). All of the housings (720, 730, 740) are rigidly secured to one another to define a unitary structure. The distal end of the push-pull cable (692) is rigidly secured to the proximal end of the proximal housing (740). The proximal end of the needle (708) is rigidly secured to the distal housing (720). The distal housing (720) defines a pair of bores (722) laterally offset from the needle (708). As shown in FIGS. 14 and 18, one bore (722) receives the distal end of the conduit (422), and the other bore (722) receives the distal end of the conduit (424). Conduits (422, 424) are wrapped around the outside of needle actuator (710) and return toward needle actuator (710) with the distal ends of conduits (422, 424) inserted into respective bores (722). Intermediate housing (730) also defines a pair of bores (732) aligned with bores (722). Each bore (732) has a respective duckbill valve (724) installed therein.

[0064] As best seen in FIG. 18 , needle actuator 710 defines chamber 742. The proximal end of needle 708 is located within chamber 742, and needle 708 is in fluid communication with chamber 742. Bore 732 is also in fluid communication with chamber 742. Thus, needle actuator 710 defines a fluid manifold. Duckbill valve 724 is configured to allow fluid to pass from conduits 422, 424 into chamber 742 while preventing fluid from passing from chamber 742 into conduits 422, 424. Thus, when bleb fluid 340 is passed through conduit 422, it exits through needle 708 and does not flow back through conduit 424. Similarly, when therapeutic agent (341) is delivered through conduit (424), the therapeutic agent (341) exits through needle (708) and does not flow back through conduit (422). As also shown in FIG. 18, an O-ring (750) is captured between distal housing (720) and proximal housing (740), thereby providing a seal that prevents fluid from escaping chamber (742) through the interface between distal housing (720) and proximal housing (740).

[0065] 2. Exemplary Injector Driver Assembly Figures 19-27B illustrate the injector driver assembly 600 and its components in further detail. While the conduits 422, 424 are omitted from Figures 19-27B, it should be understood that the conduits 422, 424 pass through the injector driver assembly 600 as previously described. As shown, the injector driver assembly 600 of this example includes a knob 602, a push button 604, a body 610, and an upper rocker plate 612. A pair of arms 606 are pivotally coupled to the body 610 and are operable to secure the injector driver assembly 600 to the wrist rest 456, as previously described. The injector driver assembly (600) may include one or more resilient members (e.g., torsion springs, leaf springs, etc.) that resiliently bias the arms (606) toward each other, thereby forcing the arms (606) to grasp the wrist rest (456).

[0066] The knob (402), rocker push button (604), plate (612), and body (610) are configured to cooperate to house several internal components within the injector driver assembly (600). As shown in Figure 19, these internal components include an array of RGB programmable LEDs (622) and a first tactile switch (624), all of which are mounted to the disk-shaped platform (620). The internal components further include an annular frame (626), a rotating cam member (640), a cam follower (650), a set of coil springs (628), and a set of ball bearings (630). Knob (402), push button (604), and cam member (640) are coupled to one another such that knob (402), push button (604), and cam member (640) are rotatable relative to the other components of the syringe driver assembly (600).

[0067] The push button 604 is configured to reciprocate vertically within the knob 402. A stud 605 (FIG. 19) projects downwardly from the underside of the stud 605 and is configured to activate a tactile switch 624 when the push button 604 is pressed downwardly relative to the knob 402. The tactile switch 624 is in communication with the control module 500 via an electrical cable 426. In this example, the control module 500 is configured to initiate the dispensing of the therapeutic agent 341 through the conduit 422 in response to the tactile switch 624 being activated via the push button 604. In some other variations, the control module 500 is configured to initiate the dispensing of the bleb fluid 340 through the conduit 424 in response to the tactile switch 624 being activated via the push button 604.

[0068] The LED 622 is configured to selectively illuminate. The knob 402 and the push button 604 are configured to allow the light emitted by the LED 622 to be visible. The LED 622 can illuminate differently based on the particular state of the system 400. For example, the LED 622 may illuminate red when the system 400 is not ready for activation of the push button 604 and green when the system 400 is ready for activation of the push button 604. As another merely illustrative example, the LED 622 may illuminate green when the needle 708 is in a fully proximal retracted position, yellow when the needle 708 is in an intermediate position but not yet extended from the cannula 702, and violet when the needle 708 is in a distally advanced position where the needle 708 protrudes from the cannula 702. Other suitable ways in which LEDs (622) may be used will be apparent to those skilled in the art in view of the teachings herein.

[0069] As shown in FIG. 20 , another tactile switch (632) is located within the body (610). The tactile switch (632) is configured to be actuated by the upper rocker plate (612), as described in further detail below. A linear sensor (660) is also located within the body (610). The linear sensor (660) is configured to be actuated by the cam follower (650), as described in further detail below. Both the tactile switch (632) and the linear sensor (660) are in communication with the control module (500) via an electrical cable (426).

[0070] FIG. 21 shows rocker plate 612 in further detail. As shown, rocker plate 612 includes a pair of downwardly-projecting tabs 614 and a downwardly-projecting stud 618. Tabs 614 are rounded and configured to fit into complementary recesses 616 ( FIG. 20 ) in body 610. This configuration of tabs 614 and recesses 616 allows rocker plate 612 to be rocked such that studs 618 can selectively actuate tactile switches 632. In this example, control module 500 is configured to initiate dispensing of bleb fluid 340 through conduit 422 in response to actuation of tactile switches 632 via rocker plate 612. In some other variations, the control module (500) is configured to initiate the delivery of the therapeutic agent (341) through the conduit (424) in response to the tactile switch (632) being actuated via the rocker plate (612).

[0071] FIGS. 22-23 show the rotating cam (640) in further detail. As shown in FIG. 22, the upper side of the rotating cam (640) includes an annular array of teeth (642) arranged in a starburst pattern. The teeth (642) are configured to engage the ball bearings (630). The upper end of each coil spring (628) presses against the underside of the annular frame (626), which serves as a mechanical ground. The lower end of each spring contacts a respective ball bearing (630), thereby resiliently pushing the ball bearings (630) into engagement with the teeth (642). The relationship between the ball bearings (630) and the teeth (642) provides sufficient resistance to rotation of the knob (602) and rotating cam (640) to prevent inadvertent rotation of the knob (602) and rotating cam (640), while still allowing intentional rotation of the knob (602) and rotating cam (640). The resistance provided by ball bearing 630 and teeth 642 also allows an operator to achieve greater precision in rotating knob 602 than the operator could achieve in the absence of such resistance. Other suitable types of structures that may be used in place of coil spring 628, ball bearing 630, and teeth 642 will be apparent to those skilled in the art in view of the teachings herein.

[0072] As shown in Figure 23, the underside of the rotating cam (640) includes a first helical cam feature (644) and a second helical cam feature (646). The helical cam features (644, 646) are generally positioned about the radial center of the rotating cam (640), although the helical cam features (644, 646) are offset from the radial center of the rotating cam (640) and from each other.

[0073] As shown in FIG. 24, the cam follower (650) of this embodiment includes a first upwardly projecting cam fin (652) and a second upwardly projecting cam fin (654). The proximal end of the push-pull cable (692) is rigidly secured to the cam follower (650). The cam fins (652, 654) are each contoured to complement the contours of the helical cam features (644, 646). As shown in FIG. 25, the cam fin (652) is configured to fit into a first space between the helical cam features (644, 646), and the cam fin (654) is configured to fit into a second space between the helical cam features (644, 646).

[0074] Due to engagement between the cam fins (652, 654) and the helical cam features (644, 646), rotation of the rotating cam (640) causes the cam follower (650) to translate longitudinally along the longitudinal axis of the push-pull cable (692). Such translation is illustrated in FIGS. 26A-26B. As shown in FIGS. 26A-26B, the cam follower (650) is captured between a pair of bosses (611) that are integral features of the body (610). The bosses (611) are configured to guide and laterally support the cam follower (650) as it translates between a proximal position (FIG. 26A) and a distal position (FIG. 26B). As previously described, the push-pull cable (692) is rigidly secured to the cam follower (650). The push-pull cable (692) is also rigidly secured to the needle actuator (710), which is in turn rigidly secured to the needle (708). It should therefore be appreciated that the needle (708) translates distally and proximally relative to the cannula (702) in response to rotation of the knob (602) relative to the body (610).

[0075] Rotating cam (640) and cam follower (650) are merely examples of features that may be used to drive push-pull cable (692) longitudinally. By way of example only, an alternative drive assembly may include a pull-pull cable with a reversing pulley (e.g., inside injector assembly (700)). By way of further example only, an alternative drive assembly may include a power line within tube and cable assembly (690) and a micromotor inside injector assembly (700). By way of further example only, an alternative drive assembly may include a power line within tube and cable assembly (690) and a nano-muscle nitinol wire inside injector assembly (700). By way of further example only, an alternative drive assembly can include a hydraulic driveline in the tube and cable assembly (690) and a piston-cylinder assembly in the injector assembly (700) to provide a hydraulic drive assembly with spring return.

[0076] The underside of the cam follower (650) is secured to a slider (664) of the linear sensor (660). The slider (664) is configured for longitudinal translation relative to the body (662) of the linear sensor (660). Because the cam follower (650) is secured to the slider (664), the slider (664) is in a proximal position (FIG. 27A) when the cam follower (650) is in a proximal position (FIG. 26A), and the slider (664) is in a distal position (FIG. 27B) when the cam follower (650) is in a distal position (FIG. 26B). The linear sensor (660) is configured to generate different data values ​​based on the longitudinal position of the slider (664) along the body (662). By way of example only, linear sensor 660 may include a linear potentiometer that generates a varying resistance value based on the longitudinal position of slider 664 along body 662. Thus, the resistance value generated across linear sensor 660 indicates the longitudinal position of needle 708 relative to cannula 702. By way of further example only, linear sensor 660 may include a sensor that senses rotation of knob 602, an optical sensor, or a sensor located within injector assembly 700 to directly monitor movement of needle actuator 710. A variety of other suitable methods for sensing movement of needle 708 will be apparent to those skilled in the art in view of the teachings herein.

[0077] The linear sensor 660 is in communication with the control module 500, such that the control module 500 can control the delivery of the bleb fluid 340 and / or therapeutic agent 341 through the conduits 422, 424 based on the longitudinal position of the needle 708 relative to the cannula 702, as sensed by the linear sensor 660. In this embodiment, whenever the linear sensor 660 detects distal advancement of the needle 708, a corresponding signal is sent to the control module 500 to automatically trigger delivery of the bleb fluid 340. This ensures that the bleb fluid 340 always flows out through the distal tip of the needle 708 whenever the needle 708 is advanced. By ensuring such constant bleb fluid flow 340, the system 400 can minimize the risk of accidental perforation of the retina 308.

[0078] In some variations, the control module 500 is programmed to automatically deliver the bleb fluid 340 at a predetermined rate based on the advancement of the needle 708 as sensed by the linear sensor 660. Even when the delivery of the bleb fluid 340 is automated, the control module 500 still delivers additional bleb fluid 340 at a predetermined rate in response to actuation of the tactile switch 632, regardless of the longitudinal position of the needle 708. It should be appreciated that delivery of the therapeutic agent 341 may also be provided by the control module 500 at a predetermined rate to deliver a predetermined volume in response to actuation of the tactile switch 624. Furthermore, delivery of the therapeutic agent 341 may be fully automated upon the operator actuating the tactile switch 624 via the push button 604. In other words, once the operator activates the tactile switch 624, the operator will not be able to selectively stop (and possibly resume) delivery of the therapeutic agent 341. Thus, the amount of time the push button 604 is depressed, or repeated depression and release of the push button, etc., will not affect delivery of the therapeutic agent 341 once the operator activates the tactile switch 624. Other examples of methods that may automatically provide delivery of the bleb fluid 340 and / or therapeutic agent 341 based on the sensed position of the needle 708 are disclosed in U.S. Patent Application No. [Attorney Docket No. END8061USNP.0614018], filed on even date herewith, entitled "Apparatus and Method to Form Entry Bleb for Subretinal Delivery of Therapeutic Agent," the disclosure of which is incorporated herein by reference.

[0079] In an exemplary use, an operator can align the magnetic pad (460), the injector driver assembly (600), and the injector assembly (700) as shown in FIG. 8. Before or after aligning the magnetic pad (460), the injector driver assembly (600), and the injector assembly (700) as shown in FIG. 8, the operator can perform the steps shown in FIGS. 9A-9L, as previously described. The operator can then form a sclerotomy in the patient's eye (301) and insert the cannula (702) into the eye (301) through the sclerotomy. To assist in forming the sclerotomy, the operator can use a marking instrument such as that described in U.S. Patent Application No. [Attorney Docket No. END8062USNP.0648021], the disclosure of which is incorporated herein by reference. To aid in the insertion of the cannula (702) into the sclerotomy along a substantially tangential path, the operator may use a guide tack such as that described in U.S. Patent Application No. [Attorney Docket No. END8062USNP.0648021], the disclosure of which is incorporated herein by reference. As another merely exemplary alternative, the operator may use a suture loop assembly (332). The cannula (702) may then be advanced to a position as shown in FIGS. 4C-4D relative to the cannula (50).

[0080] Once the cannula 702 is positioned with respect to the cannula 50 as shown in FIGS. 4C-4D , the operator can then rotate the knob 602 to distally advance the needle 708 as shown in FIGS. 4E and 5A with respect to the needle 100. During this advancement of the needle 708, the control module 500 automatically dispenses the bleb fluid 340 through the needle 708 based on a signal from the linear sensor 660, ultimately resulting in a configuration similar to that shown in FIGS. 4G and 5B . After the needle 708 has been sufficiently advanced, the operator actuates the push button 604, which causes the control module 500 to dispense the therapeutic agent 341 through the needle 708, ultimately resulting in a configuration similar to that shown in FIGS. 4H and 5C . The operator then rotates the knob 602 in the reverse direction to retract the needle 708 into the cannula 702. Once the needle (708) has been retracted, the operator then withdraws the cannula (702) from the eye (301) and securely closes the sclerotomy using any suitable technique.

[0081] IV. Exemplary Injector Assembly with Integrated Controls While the combination of the injector driver assembly (600), injector assembly (700), and push-pull cable (692) may enable increased safety, precision, and consistency in the delivery of therapeutic agent (341) to the eye (301), it may be desirable to provide the same results using smaller instrumentation. Reducing the form factor of the instrument and eliminating the push-pull cable (692) may provide easier-to-handle instrumentation and may also eliminate some of the hysteresis that may otherwise occur and adversely affect the precision of control. To that end, Figures 28-29 illustrate an exemplary alternative injector assembly (800) that is operable to provide the same results provided by the injector driver assembly (600), injector assembly (700), and push-pull cable (692) but through an even smaller device.

[0082] As shown in Figure 28, the injector assembly (800) of this embodiment includes a cannula (802), a rotation knob (820), an upper rocker plate (830), a lower rocker plate (840), and a pair of housing halves (850, 858). As shown in Figure 29, the injector assembly (800) further includes a frame member (860), a circuit board assembly (870), a needle driver (880), and a pair of magnets (848). A tubing set (810) extends proximally from the injector assembly (800). Each of these and related components is described in further detail below.

[0083] As shown in Figures 30A-30B, the cannula (802) in this example includes a sideways distal opening (804). A needle (806) is configured to be advanced distally through the opening (804), as shown in Figure 30B. In some variations, the needle (806) has a preformed curve, as described in U.S. Patent Application No. 15 / 438,918, filed February 22, 2017, entitled "Apparatus for Subretinal Administration of Therapeutic Agent via a Curved Needle," the disclosure of which is incorporated herein by reference.

[0084] As shown in FIG. 31 , housing half (850) includes an inwardly extending integral pivot strut (852) and an integral strut seat (854). While not shown, it should be understood that housing half (858) may also include an inwardly extending integral pivot strut (852) and an integral strut seat (854). As shown in FIG. 32 , lower rocker plate (840) includes a pair of outwardly extending pivot struts (842) positioned and configured to seat within the integral strut seats (854) of housing halves (850, 858) to provide a pivotal coupling between lower rocker plate (840) and housing halves (850, 858). As shown in Figures 33-34, the upper rocker plate (830) includes a pair of downwardly projecting tabs (832) having openings (834) formed therein. The openings (834) are positioned and configured to receive the pivot posts (852) of the housing halves (850, 858) to provide a pivotal connection between the lower rocker plate (840) and the housing halves (850, 858).

[0085] As shown in FIG. 35, the upper side of the circuit board assembly (870) includes a first tactile switch (872) and a linear sensor (876). The first tactile switch (872) is positioned to be actuated by a dowel (836) (FIG. 29) positioned between the first tactile switch (872) and a dowel seat (836) (FIG. 34) on the underside of the upper rocker plate (840). An operator can actuate the tactile switch (872) in this manner by pushing on the upper rocker plate (840), causing it to pivot about the pivot post (852), thereby driving the dowel (836) downward toward the first tactile switch (872). The first tactile switch 872 may communicate with the control module 500 via one or more of the wires 812 contained in the tubing set 810. By way of example only, the control module 500 may provide for delivery of a therapeutic agent 341 through the needle 806 in response to actuation of the first tactile switch 872, similar to the delivery of a therapeutic agent 341 through the needle 708 in response to actuation of the tactile switch 624 as described above.

[0086] In this embodiment, tactile switch 872 is located near the proximal end of injector assembly 800, and tactile switch 874 is located near the distal end of injector assembly 800. In addition, the pivot point of upper rocker plate 830 is located near the distal end of injector assembly 800, and the pivot point of lower rocker plate 840 is located near the distal end of injector assembly 800. Positioning the pivot point and tactile switches 872, 874 in this manner may reduce the risk of an operator inadvertently activating tactile switch 872 while intending to activate tactile switch 874, and the risk of inadvertently activating tactile switch 874 while intending to activate tactile switch 872.

[0087] Linear sensor (876) includes a slider (878) and is configured and operable similarly to previously described linear sensor (660). Linear sensor (876) communicates with control module (500) via one or more of wires (812) housed in tubing set (810). Control module (500) is configured to provide automatic delivery of bleb fluid (340) through needle (806) in response to distal movement of needle (806) as sensed by linear sensor (876).

[0088] As shown in FIG. 36, the underside of the circuit board assembly (870) includes a second tactile switch (874). The second tactile switch (874) is positioned to be actuated by an integral support post (843) ( FIG. 32 ) of the lower rocker plate (840). An operator can actuate the tactile switch (874) in this manner by pivotally pushing the housing halves (850, 858) downward, causing them to pivot about the pivot post (842), thereby driving the tactile switch (874) downward toward the integral support post (843). The second tactile switch (874) can communicate with the control module (500) via one or more of the wires (812) housed in the tubing set (810). By way of example only, the control module (500) may provide for delivery of bleb fluid (340) through needle (806) in response to activation of the second tactile switch (874), similar to the delivery of bleb fluid (340) through needle (708) in response to activation of tactile switch (632) as described above.

[0089] Referring again to FIG. 32 , a pair of recesses 846 are formed in the bottom of lower rocker plate 840. Recesses 846 are configured to receive elongated magnets 848. Magnets 848 provide a magnetic attraction to magnetic pad 460, similar to magnet 706 described above. Thus, magnets 848 allow injector assembly 800 to be removably secured to, easily repositioned on, and easily removed from magnetic pad 460. As previously described, magnetic pad 460 may take a variety of alternative forms, and other suitable structures and techniques may be used to removably secure injector assembly 800 to a patient.

[0090] As shown in Figures 37-38, the rotation knob (828), frame member (860), and needle actuator (880) are coupled to one another to form an assembly. The rotation knob (820) is operable to rotate relative to the housing halves (850, 858). The frame member (860) is configured to be integrally secured to the housing halves (850, 858), such that the frame member (860) remains stationary relative to the housing halves (850, 858). The needle actuator (880) is operable to translate relative to the housing halves (850, 858) in response to rotation of the rotation knob (820) relative to the housing halves (850, 858). As shown in Figure 39, the underside of the rotation knob (820) includes a helical cam recess (824) and a magnet (822). As shown in Figures 40-41, the frame member 860 includes a pair of support rails 862, a guide slot 864, and a magnet 866. As shown in Figure 42, the needle actuator 880 includes a pair of guide wings 882, a cam follower post 884, and a proximal opening 886.

[0091] 37-38 , guide wings 882 are sized and configured to engage support rails 862. This engagement provides vertical and lateral support for needle actuator 880 and allows needle actuator 880 to slide longitudinally relative to frame member 860. Guide slot 864 is configured to receive and accommodate cam follower post 884 as needle actuator 880 slides longitudinally relative to frame member 860. Proximal opening 886 is positioned and configured to receive slider 878 of linear sensor 876, which slides integrally with needle actuator 880.

[0092] As shown in Figures 43A-43B, the cam follower post (884) of the needle actuator (880) is configured to fit within the helical cam recess (824) of the rotation knob (820). This engagement, and the guidance provided to the cam follower post (884) by the guide slot (864), causes the needle actuator (880) to translate from a proximal position (Figure 43A) to a distal position (Figure 43B) in response to rotation of the rotation knob (820). The needle (806) is rigidly secured to the needle actuator (880), as described in more detail below, and the needle (806) translates longitudinally relative to the cannula (802) in response to rotation of the rotation knob (820). In this embodiment, magnets (822, 866) are positioned such that magnet (822) is directly above magnet (866) when rotatable knob (820) is in the home position as shown in FIG. 43A. At this stage, magnets (822, 866) prevent inadvertent rotation of rotatable knob (420) but allow intentional rotation of rotatable knob (420). In some other variations, magnets (822, 866) are positioned such that magnet (822) is directly above magnet (866) when rotatable knob (820) is in the fully rotated position as shown in FIG. 43B.

[0093] As shown in FIGS. 44-45 , needle (806) extends distally from the distal end of needle actuator (880) and is securely secured thereto by ferrule (807). Conduits (415, 423) extend proximally from the proximal end of needle actuator (880). Conduit (415) is coupled to one-way valve assembly (413), which is further coupled to conduit (422). As previously described, conduit (422) is in communication with syringe actuation cassette (550) and is configured to deliver bleb fluid (340). One-way valve assembly (413) is configured to only provide fluid delivery from conduit (422) to conduit (415) and prevent fluid delivery from conduit (415) to conduit (422). Conduit (423) is coupled to one-way valve assembly (421), which is further coupled to conduit (424). As previously described, conduit (424) is in communication with syringe actuation cassette (550) and is configured to deliver therapeutic agent (431). One-way valve assembly (421) is configured to only provide fluid delivery from conduit (424) to conduit (423) and to prevent fluid delivery from conduit (423) to conduit (424). Various structures that may be incorporated into one-way valve assemblies (413, 421) will be apparent to those skilled in the art in view of the teachings herein. Conduits (422, 424), along with wire (872), are incorporated into tubing set (810).

[0094] As shown in FIG. 45 , the distal end of the conduit 415 is inserted into a proximal opening 881 of the needle actuator 880, and the distal end of the conduit 423 is inserted into another proximal opening 883 of the needle actuator 880. The proximal opening 881 is in fluid communication with a lumen 885 formed in the needle actuator 880, and the proximal opening 883 is in fluid communication with a lumen 887 formed in the needle actuator 880. The lumens 885, 887 are in fluid communication with a chamber 889 formed in the needle actuator 880. The proximal end of the needle 806 is positioned within the chamber 889. Thus, the needle 806 receives the fluids 840, 841 delivered through the conduits 415, 413. Thus, the needle actuator (880) defines a fluid manifold.

[0095] In an exemplary use, an operator may position the magnetic pad (460) as shown in FIG. 8 and place the injector assembly (800) on the magnetic pad (460). Before or after positioning the magnetic pad (460) and the injector assembly (800), the operator may perform the steps shown in FIGS. 9A-9L as previously described. The operator may then form a sclerotomy in the patient's eye (301) and insert the cannula (802) into the eye (301) through the sclerotomy. To assist in forming the sclerotomy, the operator may use a marking instrument such as that described in U.S. Patent Application No. [Attorney Docket No. END8062USNP.0648021], the disclosure of which is incorporated herein by reference. To aid in the insertion of the cannula (802) into the sclerotomy along a substantially tangential path, the operator may use a guide tack such as that described in U.S. Patent Application No. [Attorney Docket No. END8062USNP.0648021], the disclosure of which is incorporated herein by reference. As another merely exemplary alternative, the operator may use a suture loop assembly (332). The cannula (802) may then be advanced to a position as shown in FIGS. 4C-4D relative to the cannula (50).

[0096] Once the cannula 802 is positioned relative to the cannula 50 as shown in FIGS. 4C-4D, the operator can then rotate the knob 820 to distally advance the needle 806, as shown in FIGS. 4E and 5A relative to the needle 100. During this advancement of the needle 806, the control module 500 automatically dispenses the bleb fluid 340 through the needle 806 based on a signal from the linear sensor 876, ultimately resulting in a configuration similar to that shown in FIGS. 4G and 5B. After the needle 806 has been sufficiently advanced, the operator actuates the upper rocker plate 830, which causes the control module 500 to dispense the therapeutic agent 341 through the needle 806, ultimately resulting in a configuration similar to that shown in FIGS. 4H and 5C. The operator then rotates the knob 820 in the reverse direction to retract the needle 806 into the cannula 802. Once the needle (806) has been retracted, the operator then withdraws the cannula (802) from the eye (301) and securely closes the sclerotomy using any suitable technique.

[0097] V. Exemplary Alternative Injector Systems As previously mentioned, if the therapeutic agent (341) is pumped through the conduit (424) too quickly, there may be a risk of damaging the cells in the therapeutic agent (341). This risk may be particularly pronounced during the priming process when the therapeutic agent (341) is required to travel a significant distance to reach the needle (100, 708, 806). Therefore, it may be desirable to ensure that the cells in the therapeutic agent (341) are not damaged by pumping the therapeutic agent (341) through the conduit (424) too quickly.

[0098] Figure 46 shows system 900, which represents a modified version of system 400, in which an air gap is included after therapeutic agent 341 during the priming process. System 900 in this example includes a control module 902, a BSS reservoir 910, a pump 912, a pressure regulator 914, an occlusion detector 916, a syringe assembly 918, a three-position four-way valve 920, an injector driver assembly 926, and an injector assembly 930. Control module 902 is in communication with pump 912 via a first wire 904, with occlusion detector 916 via a second wire 906, and with three-position four-way valve 920 via a third wire 908.

[0099] BSS reservoir (910) contains a volume of bleb fluid (340). BSS reservoir (910) is connected to pump (912) via conduit (911). Pump (912) is operable to pump bleb fluid (340) from BSS reservoir (910), through pressure regulator (914) and occlusion detector (916), and ultimately to three-position four-way valve (920).

[0100] Syringe 918 contains a volume of therapeutic agent 341. Syringe 918 is connected to a three-position four-way valve 920 via conduit 919.

[0101] Three-position four-way valve 920 is in fluid communication with injector driver assembly 926 via tubing 922, 924. Three-position four-way valve 920 is operable to transition between three different states. In a first state, three-position four-way valve 920 couples conduit 911 with tubing 922, thereby allowing bleb fluid 340 to be delivered through tubing 922 to injector driver assembly 926. Also in the first state, three-position four-way valve 920 prevents communication between conduit 919 and tubing 924. In a second state, three-position four-way valve 920 couples conduit 919 with tubing 924, thereby allowing therapeutic agent 341 to be delivered through tubing 924. Also, in the second state, three-position four-way valve 920 prevents communication between conduit 911 and tubing 922. In the third state, three-position four-way valve 920 couples conduit 911 with tubing 924, thereby allowing bleb fluid 340 to pass through tubing 924. Also, in the third state, three-position four-way valve 920 prevents communication between conduit 919 and tubing 922.

[0102] By way of example only, the injector driver assembly (926) may be configured and operative similarly to the injector driver assembly (600) described above. The injector driver assembly (926) is in communication with the injector assembly (930) via a tube and cable assembly (928), which may be configured and operative similarly to the tube and cable assembly (690) described above. The injector assembly (930) may be configured and operative similarly to the injector assembly (700). In some alternative variations, the injector driver assembly (926) and the injector assembly (930) are essentially combined into a single assembly, similar to the injector assembly (800) described above.

[0103] In an exemplary method of operation, system (900) begins with three-position four-way valve (920) in the position shown in FIG. 46. Pump (912) is used to prime the bleb fluid (340) pathway by forcing the bleb fluid (340) through conduit (911), tubing (922), and the corresponding conduit of tubing and cable assembly (928). Three-position four-way valve (920) is then actuated to place conduit (919) in fluid communication with tubing (924). Syringe (918) is then actuated to inject a volume of therapeutic agent (341) (e.g., approximately 280 μL) through tubing (924). By way of example only, tube (924) may have a length of about 84 inches and an inner diameter of about 0.03 inches to about 0.04 inches.

[0104] As a volume of therapeutic agent (341) is injected into tubing (924), an air gap is injected into tubing (924) after the volume of therapeutic agent (341). In some variations, syringe (918) may be replaced with another syringe containing air, and the air-filled syringe is used to inject the air gap into tubing (924) while three-position four-way valve (920) remains in a state where conduit (919) is in fluid communication with tubing (924). In some other variations, three-position four-way valve (920) is switched to a state where conduit (911) is in fluid communication with tubing (924), and an air gap is provided through conduit (911). In either case, by way of example only, the air gap may have a volume of approximately 10 μL.

[0105] After the air gap is injected, if the three-position four-way valve (920) is not already in fluid communication with the conduit (911) and the tubing (924), the three-position four-way valve (920) is switched to a state where the conduit (911) is in fluid communication with the tubing (924). The pump (912) is then activated to pump a volume of bleb fluid (340) from the BSS reservoir (910) and into the tubing (924). The volume of bleb fluid (340) is selected to ensure that the therapeutic agent (341) reaches the injector assembly (930). The air gap between the bleb fluid (340) and the therapeutic agent (341) can prevent the bleb fluid (340) and the therapeutic agent (341) from mixing.

[0106] At this stage, tubing (922, 924) and injector assembly (930) are fully primed, and system (900) is ready to be used in the procedure as previously described. During this procedure, three-position four-way valve (920) is first switched to place conduit (911) in fluid communication with tubing (922) to provide bleb fluid (340) to the subretinal space. Three-position four-way valve (920) is then switched to place conduit (911) in fluid communication with tubing (924) to provide therapeutic agent (341) to the subretinal space. Bleb fluid (340) and therapeutic agent (341) can be provided to the subretinal space in accordance with the teachings previously described with respect to Figures 4E-4G and 5A-5C.

[0107] VI. Exemplary Alternative Needle Guides As previously mentioned, cannula 50 includes an internal needle guide 60 that slidably receives needle 100 and guides it at a particular exit angle from side opening 56 of cannula 50. It should also be understood that cannula 702 and cannula 802 may each include an internal needle guide. While such a needle guide needs to be flexible to conform to the inner curvature of eye 301, it may also be important for such a needle guide to maintain axial stiffness (tensile strength) to prevent elongation of the needle guide during operation. Otherwise, elongation of the needle guide could adversely affect smooth movement of the needle through the needle guide. Therefore, it may be desirable to provide a needle guide that has substantial lateral flexibility as well as substantial axial stiffness.

[0108] Figure 47 illustrates an exemplary needle guide (950) that may be disposed within any of the cannulas (50, 702, 802) described herein. The needle guide (950) of this example is formed of a metallic material and has a laterally oriented opening (954) at the distal end of the shaft (952) and a bent section (960) including a linear array of cutouts (970) formed proximal to the laterally oriented opening (954). The laterally oriented openings (954) may be positioned to correspond with the side openings of the cannula (e.g., any of the cannulas (50, 702, 802)) and thereby guide a needle through the side opening of the cannula. The cutouts (970) may be formed using laser cutting techniques or any other suitable technique.

[0109] As best seen in Figure 48, each cutout 970 includes an angularly extending portion 972 and a pair of longitudinally extending portions 974. Each cutout 970 in the linear array of cutouts 970 is angularly offset by 90° relative to adjacent cutouts 970 in the linear array of cutouts 970. The configuration and arrangement of cutouts 970 in this embodiment provides needle guide 950 with substantial lateral flexibility, while also providing needle guide 950 with substantial axial stiffness.

[0110] VII. Exemplary Combinations The following examples relate to various non-exhaustive methods in which the teachings herein may be combined or applied. It should be understood that the following examples are not intended to limit the scope of any claims that may be presented from time to time in this application or any subsequent application thereto. No disclaimer is intended. The following examples are provided for illustrative purposes only. It is contemplated that the various teachings herein may be arranged and applied in many other ways. It is also contemplated that certain features referred to in the following examples may be omitted in some variations. Accordingly, none of the aspects or features referred to below should be considered essential unless later expressly indicated as such by the inventors or the inventors' successors in interest. If any claim including additional features beyond those referred to below is presented in this application or any subsequent application thereto, the additional features shall not be presumed to have been added for patentability reasons.

[0111] Example 1 The device includes: (a) a pad assembly sized and configured to be placed on a patient's forehead; (b) an injector assembly including: (i) a body configured to be removably secured to the pad assembly; (ii) a flexible cannula extending distally from the body and sized to be inserted through an incision in the patient's eye; and (iii) a needle slidably disposed within the cannula; (c) an injector driver operable to drive the needle longitudinally relative to the flexible cannula; and (d) a fluid source assembly in fluid communication with the needle. Example 2 In the device described in Example 1, The injector driver is built into the main body of the instrument. Example 3 10. The device of any one or more of Example 1, The instrument, wherein the injector driver is remotely coupled to the injector assembly via a flexible drive cable. Example 4 In one or more of the devices described in Examples 1 to 3, The device, wherein the injector assembly includes a magnet, the magnet configured to removably secure the body to the pad. Example 5 In the device described in Example 4, The pad includes a plurality of ferrous elements. Example 6 In any one or more of Examples 1 to 5, The injector assembly further includes a needle actuator positioned within the body, the needle being rigidly secured to the needle actuator, the needle actuator configured for translational movement relative to the body to thereby drive the needle longitudinally relative to the cannula. Example 7 In the device described in Example 6, The device, wherein the needle actuator further includes at least two fluid inputs in fluid communication with the needle, the needle actuator configured to form a manifold. Example 8 In any one or more of Examples 1 to 7, An instrument wherein the injector driver includes a rotation knob, the rotation knob being rotatable to drive the needle longitudinally relative to the flexible cannula. Example 9 In the device described in Example 8, The instrument, wherein the rotation knob includes a helical cam feature configured to cooperate with another needle drive element to thereby drive the needle longitudinally in response to rotational movement of the rotary actuator. Example 10 In one or more of the devices of Examples 8-9, The injector driver further includes a translatable member having a cam follower coupled with a helical cam feature, the cam follower and the helical cam feature cooperating to thereby translate rotational movement of the rotatable knob into longitudinal movement of the needle. Example 11 In the device according to any one or more of Examples 1 to 10, The device, wherein the injector driver further includes a first user input feature, the first user input feature operable to provide delivery of the therapeutic agent through the needle. Example 12 In the device described in Example 11, The first user input feature includes a push button. Example 13 In any one or more of Examples 1 to 13, The injector driver further includes a bleb fluid delivery input feature, the bleb fluid delivery input feature operable to provide delivery of bleb fluid through the needle. Example 14 In the device described in Example 13, The device wherein the bleb fluid delivery feature includes a sensor, the sensor configured to sense the position of the needle relative to the body. Example 15 In the device described in Example 14, The instrument, wherein the sensor includes a linear potentiometer. Example 16 In any one or more of Examples 1 to 15, The device, wherein the fluid source assembly includes a syringe actuation cassette configured to provide automatic actuation of the syringe, thereby expelling the contents of the syringe through the needle. Example 17 In any one or more of Examples 1 to 16, The apparatus, wherein the fluid source assembly further includes a thawing module, the thawing module operable to thaw the volume of frozen therapeutic agent. Example 18 1. An apparatus comprising: (a) a pad assembly sized and configured to be placed on a patient's forehead and including at least one ferrous element; and (b) an injector assembly including: (i) a body configured to be removably secured to the pad assembly; (ii) a flexible cannula extending distally from the body and sized to be inserted through an incision in the patient's eye; (iii) a needle slidably disposed within the cannula; (iv) a needle driver slidably disposed within the body, the needle driver operable to drive the needle longitudinally relative to the cannula; and (v) at least one magnet positioned to interact with the at least one ferrous element, thereby removably coupling the injector assembly with the pad assembly. Example 19 The method includes: (a) positioning a pad on a patient's forehead, the pad including at least one ferrous element; (b) positioning an injector assembly over the pad, the injector assembly including at least one magnet, the at least one magnet removably securing the injector assembly on the pad; (c) inserting a flexible cannula of the injector assembly through the patient's eye and into a sclerotomy created therein; (d) advancing a needle distally through the flexible cannula; and (e) administering a therapeutic agent into the patient's eye through the needle. Example 20 In the method described in Example 19, The method, wherein the act of distally advancing the needle includes rotating a knob of an injector assembly, and the act of administering the therapeutic agent includes activating a switch of the injector assembly.

[0112] VIII. Other It should be understood that any of the variations of the instruments described herein may include various other features in addition to or in place of those described above. By way of example only, any of the devices herein may also include one or more of the various features disclosed in any of the various references incorporated by reference herein.

[0113] It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Accordingly, the foregoing teachings, expressions, embodiments, examples, etc. should not be considered in isolation from one another. Various suitable ways in which the teachings herein can be combined will be readily apparent to those of skill in the art in view of the teachings herein. Such modifications and variations are intended to be within the scope of the claims.

[0114] It should be recognized that any patent, publication, or other disclosure material said to be incorporated by reference herein is incorporated herein, in whole or in part, only to the extent that the incorporated material does not contradict existing definitions, statements, or other disclosure material set forth in this disclosure. Thus, to the extent necessary, the disclosure expressly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, said to be incorporated herein by reference but which contradicts existing definitions, statements, or other disclosure material set forth herein, is only incorporated to the extent that no contradiction arises between the incorporated material and the existing disclosure material.

[0115] The aforementioned variants may be designed to be disposed of after a single use, or they may be designed to be used multiple times. In either case, or both, the variants may be reconditioned for reuse after at least one use. Reconditioning may include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular parts, and subsequent reassembly. In particular, some variants of the device may be disassembled, and any number of particular parts or components of the device may be selectively replaced or removed in any combination. Following cleaning and / or replacement of particular parts, some variants of the device may be reassembled for subsequent use at a reconditioning facility or by an operator immediately prior to a procedure. Those skilled in the art will recognize that reconditioning of a device may utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. The use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0116] By way of example only, the variants described herein can be sterilized before and / or after treatment. In one sterilization technique, the device is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and device can then be placed in a radiation field that can penetrate the container, such as gamma rays, x-rays, or high-energy electrons. The radiation can kill bacteria on the device and in the container. The sterilized device can then be stored in a sterile container for later use. The device can also be sterilized using any other technique known in the art, including, but not limited to, beta or gamma radiation, ethylene oxide, or steam.

[0117] While various embodiments of the present invention have been illustrated and described, further adaptations of the methods and systems described herein may be achieved by appropriate modifications by those skilled in the art without departing from the scope of the present invention. Some of these potential modifications have been mentioned; others will be apparent to those skilled in the art. For example, the examples, embodiments, geometric features, materials, dimensions, proportions, steps, etc. described above are illustrative and not required. Accordingly, the scope of the present invention should be considered in terms of the claims, and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.

[0118] [Embodiment] (1) In the case of equipment: (a) a pad assembly sized and configured to be placed on a patient's forehead; (b) an injector assembly, (i) a body configured to be removably secured to the pad assembly; (ii) a flexible cannula extending distally from the body and sized for insertion through an incision in the patient's eye; and (iii) a needle slidably disposed within the cannula; an injector assembly including: (c) an injector driver operable to drive the needle longitudinally relative to the flexible cannula; (d) a fluid source assembly in fluid communication with the needle; Including, fixtures. (2) In the device according to embodiment 1, The injector driver is integrated into the body. (3) In the device according to embodiment 1, The injector driver is remotely coupled to the injector assembly via a flexible drive cable. (4) In the device according to embodiment 1, The device, wherein the injector assembly includes a magnet, the magnet configured to removably secure the body to the pad. (5) In the device according to embodiment 4, The pad includes a plurality of ferrous elements.

[0119] (6) In the device according to embodiment 1, The injector assembly further includes a needle actuator positioned within the body, the needle being rigidly secured to the needle actuator, the needle actuator configured for translational movement relative to the body to thereby drive the needle longitudinally relative to the cannula. (7) In the device according to embodiment 6, The device, wherein the needle actuator further includes at least two fluid inputs in fluid communication with the needle, the needle actuator configured to form a manifold. (8) In the device according to embodiment 1, An instrument wherein the injector driver includes a rotation knob, the rotation knob being rotatable to drive the needle longitudinally relative to the flexible cannula. (9) The device according to embodiment 8, the rotation knob includes a helical cam feature configured to cooperate with another needle drive element to thereby drive the needle longitudinally in response to rotational movement of the rotary actuator. (10) The device according to embodiment 8, The injector driver further includes a translatable member having a cam follower coupled with the helical cam feature, the cam follower and the helical cam feature configured to cooperate to thereby translate rotational movement of the rotatable knob into longitudinal movement of the needle.

[0120] (11) The device according to embodiment 1, The device, wherein the injector driver further includes a first user input feature, the first user input feature operable to provide delivery of a therapeutic agent through the needle. (12) The device according to embodiment 11, The apparatus, wherein the first user input feature includes a push button. (13) The device according to embodiment 1, The device wherein the injector driver further includes a bleb fluid delivery input feature, the bleb fluid delivery input feature operable to provide delivery of bleb fluid through a needle. (14) The device according to embodiment 13, The device, wherein the bleb fluid delivery feature includes a sensor, the sensor configured to sense the position of the needle relative to the body. (15) The device according to embodiment 14, The instrument, wherein the sensor comprises a linear potentiometer.

[0121] (16) The device according to embodiment 1, The device wherein the fluid source assembly includes a syringe actuation cassette configured to provide automatic actuation of a syringe to thereby expel the contents of the syringe through the needle. (17) The device according to embodiment 1, The apparatus, wherein the fluid source assembly further includes a thawing module, the thawing module operable to thaw a volume of frozen therapeutic agent. (18) In the case of equipment, (a) a pad assembly sized and configured to be placed on a patient's forehead, the pad assembly including at least one ferrous element; (b) an injector assembly, (i) a body configured to be removably secured to the pad assembly; (ii) a flexible cannula extending distally from the body and sized for insertion through an incision in the patient's eye; (iii) a needle slidably disposed within the cannula; (iv) a needle driver slidably disposed within the body, the needle driver operable to drive the needle longitudinally relative to the cannula; and (v) at least one magnet positioned to interact with the at least one ferrous element, thereby removably coupling the injector assembly with the pad assembly; an injector assembly including: Including, fixtures. (19) In the method, (a) positioning a pad on a patient's forehead, said pad including at least one ferrous element; (b) positioning an injector assembly over the pad, the injector assembly including at least one magnet, the at least one magnet removably securing the injector assembly onto the pad; (c) inserting a flexible cannula of the injector assembly through the patient's eye and into a sclerotomy created therein; (d) advancing a needle distally through the flexible cannula; (e) administering a therapeutic agent into the patient's eye through the needle; A method comprising: (20) In the method according to embodiment 19, The act of distally advancing the needle comprises rotating a knob of the injector assembly, and the act of administering the therapeutic agent comprises activating a switch of the injector assembly. [Brief explanation of the drawings]

[0122] [Figure 1] 1 depicts a perspective view of an exemplary device for subretinal administration of a therapeutic agent via a suprachoroidal approach. [Figure 2] 2 depicts a perspective view of the distal end of an exemplary cannula that may be incorporated into the device of FIG. 1; [Figure 3A]3 depicts a cross-sectional side view of the cannula of FIG. 2, the cross-section being taken along line 3-3 of FIG. 2, with the needle in a first longitudinal position. [Figure 3B] 3 depicts a cross-sectional side view of the cannula of FIG. 2, the cross-section being taken along line 3-3 of FIG. 2, with the needle in a second longitudinal position. [Figure 4A] Draw a cross-section of the patient's eye with the chandelier in place. [Figure 4B] A cross-sectional view of the eye is depicted in Figure 4A, where a suture loop has been attached to the eye and a sclerotomy has been performed. [Figure 4C] 4A depicts the cross-sectional view of the eye of FIG. 4A with the instrument of FIG. 1 inserted through the sclerotomy opening and between the sclera and choroid of the eye. [Figure 4D] 4A depicts a cross-sectional view of the eye of FIG. 4A in which the device of FIG. 1 is visualized directly at the fundus between the sclera and choroid. [Figure 4E] The needle of the instrument of Figure 1 is advanced under direct visualization at the fundus, compressing the outer surface of the choroid and "tenting" the choroid, depicting the cross-sectional view of the eye in Figure 4A. [Figure 4F] A cross-sectional view of the eye in Figure 4A is depicted where the needle is dispensing the leading bleb with direct visualization at the fundus, with the needle between the sclera and choroid and the leading bleb in the subretinal space between the choroid and retina. [Figure 4G] 4A depicts a cross-sectional view of the eye in which a needle is dispensing a therapeutic agent into the eye between the sclera and choroid at the fundus. [Figure 5A] 4E depicts a detailed cross-sectional view of the eye of FIG. 4A depicted in the state shown in FIG. 4E. [Figure 5B] 4F depicts a detailed cross-sectional view of the eye of FIG. 4A depicted in the state shown in FIG. 4F. [Figure 5C] 4G depicts a detailed cross-sectional view of the eye of FIG. 4A depicted in the state shown in FIG. 4G. [Figure 6] 1 depicts a perspective view of an exemplary system for subretinal administration of a therapeutic agent via a suprachoroidal approach. [Figure 7] 7 depicts a top view of a kit containing some components of the system of FIG. 6. [Figure 8]7 depicts a perspective view of the components of the system of FIG. 6 mounted near a patient. [Figure 9A] 7 depicts a perspective view of the control module of the system of FIG. 6 during the first stage of treatment. [Figure 9B] 9B depicts a perspective view of the control module of FIG. 9A with the cover in an open position during a second stage of the procedure of FIG. 9A. [Figure 9C] 9B depicts a perspective view of the control module of FIG. 9A during a third stage of the procedure of FIG. 9A, with the cover in an open position and a therapeutic substance vial inserted into the thawing chamber of the control module. [Figure 9D] 9B depicts a perspective view of the control module of FIG. 9A with the cover in a closed position during a fourth stage of the procedure of FIG. 9A. [Figure 9E] 9B depicts a perspective view of the therapeutic substance vial of FIG. 9C being inserted into the syringe adapter during a fifth stage of the procedure of FIG. 9A. [Figure 9F] 9E depicts a perspective view of a syringe withdrawing therapeutic substance from the therapeutic substance vial of FIG. 9C through the syringe adapter of FIG. 9E during a sixth stage of the procedure of FIG. 9A. [Figure 9G] 9F depicts a perspective view of the syringe of FIG. 9F being inserted into the syringe actuation cassette during the seventh stage of the procedure of FIG. 9A. [Figure 9H] 9G depicts a perspective view of a spike from a first conduit of the syringe actuation cassette of FIG. 9G being inserted into a balanced salt solution bottle during an eighth stage of the procedure of FIG. 9A. [Figure 9I] 9G depicts a perspective view of the syringe actuation cassette of FIG. 9G inserted into the control module of FIG. 9A with the cover in an open position during a ninth stage of the procedure of FIG. 9A. [Figure 9J] 9G depicts a perspective view of the syringe actuation cassette of FIG. 9G fully installed in the control module of FIG. 9A with the cover in the open position during the tenth stage of the procedure of FIG. 9A. [Figure 9K] 9B depicts a perspective view of the control module of FIG. 9A with the cover in a closed position during an eleventh stage of the procedure of FIG. 9A. [Figure 9L]9B depicts a perspective view of the control module of FIG. 9A with the cover in a closed position during a twelfth stage of the procedure of FIG. 9A. [Figure 10] 7 depicts a perspective view of an exemplary magnetic pad that may be used as part of the system of FIG. 6. [Figure 11] 7 depicts a perspective view of another exemplary magnetic pad that may be used as part of the system of FIG. 6. [Figure 12] 7 depicts a perspective view of another exemplary magnetic pad that may be used as part of the system of FIG. 6. [Figure 13] 7 depicts a perspective view of an exemplary injector assembly and an exemplary injector driver assembly of the system of FIG. 6. [Figure 14] 14 depicts an exploded perspective view of the injector assembly of FIG. 13. [Figure 15A] FIG. 14 depicts a top view of the injector assembly of FIG. 13 with the top cover removed and the needle actuator in the proximal position. [Figure 15B] FIG. 14 depicts a top view of the injector assembly of FIG. 13 with the top cover removed and the needle actuator in the distal position. [Figure 16] 15B depicts an exploded perspective view of the needle actuator of FIG. 15A. [Figure 17] 15B depicts an exploded perspective cross-sectional view of the needle actuator of FIG. 15A. [Figure 18] 15B depicts a top cross-sectional view of the needle actuator of FIG. 15A. [Figure 19] 14 depicts an exploded perspective view of the injector driver assembly of FIG. 13; [Figure 20] 14 depicts a perspective view of the bottom portion of the injector driver assembly of FIG. 13; [Figure 21] 14 depicts a perspective view of the upper rocker plate of the injector driver assembly of FIG. 13; [Figure 22] 14 depicts a perspective view of a rotating cam member of the injector driver assembly of FIG. 13; [Figure 23] 23 depicts another perspective view of the rotating cam member of FIG. 22. [Figure 24] 14 depicts a perspective view of a cam follower of the injector driver assembly of FIG. 13; [Figure 25]25 depicts an exploded perspective view of the rotating cam member of FIG. 22 and the cam follower of FIG. 24. [Figure 26A] 25 depicts a top view of the injector driver assembly of FIG. 13 with the upper portion removed and the cam follower of FIG. 24 in a proximal position. [Figure 26B] 25 depicts a top view of the injector driver assembly of FIG. 13 with the upper portion removed and the cam follower of FIG. 24 in a distal position. [Figure 27A] 14 depicts a perspective view of an exemplary linear sensor of the injector driver assembly of FIG. 13 with the slider of the sensor in a proximal position. [Figure 27B] 27B depicts a perspective view of the linear sensor of FIG. 27A with the slider of the sensor in a distal position. [Figure 28] 7 depicts a perspective view of an exemplary alternative injector assembly that may be incorporated into the system of FIG. 6. [Figure 29] 29 depicts an exploded perspective view of the injector assembly of FIG. 28. [Figure 30A] 29 depicts a perspective view of the distal end of the cannula of the injector assembly of FIG. 28 with the needle retracted within the cannula. [Figure 30B] 30B depicts a perspective view of the distal end of the cannula of FIG. 30A with a needle extending from the cannula. [Figure 31] 29 depicts a perspective view of a housing half of the injector assembly of FIG. 28. [Figure 32] 29 depicts a perspective view of the lower rocker plate of the injector assembly of FIG. 28. [Figure 33] 29 depicts a perspective view of the upper rocker plate of the injector assembly of FIG. 28. [Figure 34] 34 depicts another perspective view of the upper rocker plate of FIG. 33; [Figure 35] 29 depicts a perspective view of the circuit board assembly of the injector assembly of FIG. 28. [Figure 36] 36 depicts another perspective view of the circuit board assembly of FIG. 35. [Figure 37] 29 depicts a perspective view of the needle actuation assembly of the injector assembly of FIG. 28. [Figure 38] 38 depicts a front view of the frame member and needle driver of the needle actuation assembly of FIG. 37; [Figure 39] 38 depicts a perspective view of the rotating cam of the needle actuation assembly of FIG. 37; [Figure 40] Draw a top view of the frame member of Figure 38. [Figure 41] 39 depicts a perspective view of the frame member of FIG. 38. [Figure 42] 39 depicts a perspective view of the needle driver of FIG. 38. [Figure 43A] 43 depicts a cross-sectional view of the needle actuation assembly of FIG. 37 along line 43-43 of FIG. 37, with the rotating cam of FIG. 39 in a first angular position and the needle driver of FIG. 38 in a proximal position. [Figure 43B] 43 depicts a cross-sectional view of the needle actuation assembly of FIG. 37 along line 43-43 of FIG. 37, with the rotating cam of FIG. 39 in a second angular position and the needle driver of FIG. 38 in a distal position. [Figure 44] FIG. 39 depicts a top view of the needle driver of FIG. 38 with a fluid conduit connected thereto. [Figure 45] 45 depicts a cross-sectional view of the needle driver of FIG. 38 along line 45-45 of FIG. 42 with the fluid conduit of FIG. 44 connected thereto. [Figure 46] 1 depicts a schematic diagram of an exemplary alternative system for subretinal administration of a therapeutic agent via a suprachoroidal approach. [Figure 47] 1 depicts a perspective view of an exemplary alternative needle guide that may be disposed within the cannula of the injector. [Figure 48] 48 depicts a cross-sectional view of a portion of the needle guide of FIG. 47.

Claims

1. In the instrument, (a) an injector assembly, comprising: (i) a body; (ii) a flexible cannula extending distally from the body, the flexible cannula being sized for insertion through an incision in a patient's eye; and (iii) a longitudinally extending needle slidably disposed within the flexible cannula; an injector assembly including: (b) an injector driver operable to drive the needle in the longitudinal direction relative to the flexible cannula; (c) a fluid source assembly in fluid communication with the needle; (d) a magnetic pad assembly sized and configured to be placed on the patient's forehead having a curvature in a sagittal plane, the magnetic pad assembly at least partially conforming to the curvature of the patient's forehead when placed on the patient's forehead, the magnetic pad assembly including an adhesive; the body of the injector assembly is configured to be removably secured to the magnetic pad assembly in a plurality of positions and a plurality of orientations; the injector assembly further includes a magnet configured to removably secure the body to the magnetic pad assembly via magnetic attraction, the magnet being held in a stationary position relative to the body; The plurality of directions differ both in height relative to a coronal plane and in directions within the coronal plane.

2. 10. The device of claim 1, The injector driver is integrated into the body.

3. 10. The device of claim 1, The injector driver is remotely coupled to the injector assembly via a flexible drive cable.

4. 10. The device of claim 1, The magnetic pad assembly includes at least one ferrous element.

5. 10. The device of claim 1, the injector assembly further includes a needle actuator positioned within the body, the needle being rigidly secured to the needle actuator, the needle actuator configured for translational movement relative to the body to thereby drive the needle in the longitudinal direction relative to the flexible cannula.

6. 6. The device of claim 5, The device, wherein the needle actuator further includes at least two fluid inputs in fluid communication with the needle, the needle actuator configured to form a manifold.

7. 10. The device of claim 1, An instrument wherein the injector driver includes a rotation knob, the rotation knob being rotatable to drive the needle in the longitudinal direction relative to the flexible cannula.

8. 8. The device of claim 7, the rotatable knob includes a helical cam feature configured to cooperate with another needle drive element to thereby drive the needle in the longitudinal direction in response to rotational movement of the rotatable knob.

9. 9. The device of claim 8, The injector driver further includes a translatable member having a cam follower coupled with the helical cam feature, the cam follower and the helical cam feature configured to cooperate with one another to thereby translate the rotational movement of the rotatable knob into the longitudinal movement of the needle.

10. 10. The device of claim 1, The device, wherein the injector driver further includes a first user input feature, the first user input feature operable to provide delivery of a therapeutic agent through the needle.

11. 11. The device of claim 10, The apparatus, wherein the first user input feature includes a push button.

12. 10. The device of claim 1, The injector driver further includes a bleb fluid delivery input feature, the bleb fluid delivery input feature operable to provide delivery of bleb fluid through the needle.

13. 13. The device of claim 12, The device wherein the bleb fluid delivery input feature includes a sensor configured to sense a position of the needle relative to the body, the sensor including a linear potentiometer.

14. 10. The device of claim 1, The device wherein the fluid source assembly includes a syringe actuation cassette configured to provide automatic actuation of a syringe to thereby expel the contents of the syringe through the needle.

15. 10. The device of claim 1, The apparatus, wherein the fluid source assembly further includes a thawing module, the thawing module operable to thaw a volume of frozen therapeutic agent.

Images