Ophthalmic implant and delivery system with pressure sensor

Abstract

To provide an improved system for delivering ocular implants into an eye.SOLUTION: A system comprises: a cannula defining a passageway extending from a proximal end to a distal end, the cannula having a distal opening extending through a side wall and the distal end of the cannula to form a trough, a curved distal portion, a curved intermediate portion, and a proximal portion, the cannula further including a first pressure sensor disposed within the trough; an ocular implant disposed within the passageway of the cannula; and a delivery tool having a distal interlocking portion engaging a complementary interlocking portion of the ocular implant.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates generally, but not limited to, medical devices and methods for manufacturing medical devices. The present invention generally relates to devices implanted within the eye. More particularly, the present invention relates to devices that facilitate the movement of fluid from one region of the eye to another region of the eye. Further, the present disclosure relates to systems, devices, and methods for delivering an ophthalmic implant into the eye.

Background Art

[0002] According to a draft by the National Eye Institute (NEI) of the United States National Institutes of Health (NIH), glaucoma is now the leading cause of irreversible blindness in the world and the second leading cause of blindness after cataract worldwide. Therefore, the NEI draft concludes that "it is important to continue to devote considerable attention and resources to determining the pathophysiology and treatment of this disease." Glaucoma researchers have found a strong correlation between high intraocular pressure and glaucoma. For this reason, ophthalmic treatment specialists constantly examine patients for glaucoma by measuring intraocular pressure using a device known as a tonometer. Many modern tonometers perform this measurement by suddenly blowing air onto the outer surface of the eye.

[0003] The eye can be conceptualized as a sphere filled with fluid. There are two types of liquids inside the eye. The chamber behind the lens is filled with a viscous fluid known as vitreous humor. The chamber in front of the lens is filled with a liquid known as aqueous humor. When a human looks at an object, they are always looking at that object through both the vitreous humor and the aqueous humor.

[0004] When humans see an object, they always see it through the cornea and the lens of the eye. Because they are transparent, the cornea and lens cannot contain blood vessels. Therefore, blood does not flow through the cornea and lens to nourish these tissues and remove waste products from them. Instead, these functions are performed by aqueous humor. The continuous flow of aqueous humor through the eye nourishes the parts of the eye that do not have blood vessels (e.g., the cornea and lens). This flow of aqueous humor also removes waste products from these tissues.

[0005] Aqueous humor is produced by an organ known as the ciliary body. The ciliary body contains epithelial cells that continuously secrete aqueous humor. In a healthy eye, when new aqueous humor is secreted by the epithelial cells of the ciliary body, the flow of aqueous humor flows out of the anterior chamber, through the trabecular network, and into Schlemm's canal. This excess aqueous humor enters the venous bloodstream from Schlemm's canal and is carried away with the venous blood, leaving the eye.

[0006] When the eye's natural drainage mechanism malfunctions, the pressure inside the eye begins to rise. Researchers have theorized that prolonged exposure to high intraocular pressure can cause damage to the optic nerve, which transmits sensory information from the eye to the brain. This damage to the optic nerve leads to loss of peripheral vision. As glaucoma progresses, more and more of the field of vision is lost, and eventually the patient becomes completely blind.

[0007] In addition to drug therapy, various surgical procedures are performed for glaucoma. For example, shunts are implanted to drain aqueous humor from the anterior chamber to the extraocular vein (Non-Patent Document 1). Other implants for treating early glaucoma connect from the anterior chamber to the subconjunctival bleb (e.g., (Patent Document 1) and (Patent Document 2)). Still others are shunts connecting from the anterior chamber to a point inside Schlemm's canal ((Non-Patent Document 2); (Patent Document 3); (Patent Document 4)). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] U.S. Patent No. 4,968,296 [Patent Document 2] U.S. Patent No. 5,180,362 [Patent Document 3] U.S. Patent No. 6,450,984 [Patent Document 4] U.S. Patent No. 6,450,984 [Non-patent literature]

[0009] [Non-Patent Document 1] Lee and Scheppens, "Aqueous-venous shunt and intraocular pressure," Investigative Opthalmology, February 1966. [Non-Patent Document 2] Spiegel et al., "Schlemm's canal implant: a new method to lower intraocular pressure in patients with POAG?", Ophthalmic Surgery and Lasers, June 1999. [Overview of the project]

[0010] This disclosure provides alternative forms of design, materials, and manufacturing methods for medical devices. In the first example, an ophthalmic implant fitted to be at least partially present within a portion of Schlemm's canal of the eye comprises a tubular body having an inner surface and an outer surface, the tubular body extending within a curved volume, the longitudinal axis of the curved volume forming an arc; a plurality of opening regions and support regions formed within the tubular body, the support regions surrounding the plurality of opening regions; and a pressure sensor positioned on the inner surface of the tubular body, the tubular body having a diameter of 0.127 mm (0.005 inches) to 1.016 mm (0.04 inches).

[0011] In place of or in addition to any of the above embodiments, the pressure sensor includes a micro-electro-mechanical system (MEMS) pressure sensor.

[0012] In addition to or instead of any of the above embodiments, the pressure sensor includes an antenna for transmitting data from the pressure sensor to a remote location. In addition to or instead of any of the above embodiments, the data is automatically transmitted from the remote location to the second remote device.

[0013] In addition to or instead of any of the embodiments described above, the support region is connected by one or more spine regions. In addition to or instead of any of the embodiments described above, each support region is circumferentially wavy when it extends longitudinally between the first spinal region and the second spinal region.

[0014] In place of or in addition to any of the above embodiments, the implant is formed from a shape memory material that has a shape approximately equal to the curved volume. Another exemplary system includes a cannula defining a passage extending from a proximal to anterior portion, further comprising a first pressure sensor positioned within the trough, having an apical opening extending through the side walls and apical portion of the cannula to form a trough, a curved apical portion, a curved intermediate portion, and a proximal portion; an ophthalmic implant positioned within the passage of the cannula; and a delivery tool having an apical interlocking portion that engages with complementary interlocking portions of the ophthalmic implant.

[0015] In place of or in addition to any of the embodiments described above, the first pressure sensor includes a micro-electromechanical system (MEMS) pressure sensor. In place of or in addition to any of the above embodiments, the first pressure sensor includes an antenna for transmitting data from the first pressure sensor to a remote location.

[0016] In place of or in addition to any of the above embodiments, a second pressure sensor disposed on or within an ophthalmic implant is further included. In place of or in addition to any of the embodiments described above, the second pressure sensor includes a micro-electromechanical system (MEMS) pressure sensor.

[0017] In place of or in addition to any of the above embodiments, the second pressure sensor includes an antenna for transmitting data from the second pressure sensor to a remote location. In place of or in addition to any of the above embodiments, the interlocking portion at the tip of the delivery tool and the complementary interlocking portion of the ophthalmic implant form a mechanical interlocking connection when the interlocking portion of the delivery tool is proximal to the trough of the cannula.

[0018] Another exemplary ophthalmic implant kit includes an ophthalmic implant adapted to be at least partially present within a portion of the eye's Schlemm's canal. The implant is a tubular body having an inner surface and an outer surface, the tubular body extending within a curved volume, the longitudinal axis of the curved volume forming an arc. The tubular body includes a plurality of opening regions and strut regions formed within the tubular body, the strut regions surrounding the plurality of opening regions, and a first pressure sensor disposed on the inner surface of the tubular body. The tubular body has a diameter of 0.127 millimeters (0.005 inches) to 1.016 millimeters (0.04 inches). The kit further includes a cannula defining a passage extending from a proximal end to a distal end, the cannula having a tip opening extending through the sidewall and tip of the cannula to form a trough, a curved tip portion, a curved intermediate portion, and a proximal portion, and a delivery tool having a tip interlocking portion that engages a complementary interlocking portion of the ophthalmic implant.

[0019] Instead of or in addition to any of the above embodiments, the first pressure sensor includes a microelectromechanical systems (MEMS) pressure sensor. Instead of or in addition to any of the above embodiments, the first pressure sensor includes an antenna for transmitting data from the first pressure sensor to a remote location.

[0020] Instead of or in addition to any of the above embodiments, the data is automatically transmitted from the remote location to a second remote device. Instead of or in addition to any of the above embodiments, the kit further includes a second pressure sensor disposed within the trough of the cannula.

[0021] Instead of or in addition to any of the above embodiments, the second pressure sensor includes a microelectromechanical systems (MEMS) pressure sensor and an antenna for transmitting data from the second pressure sensor to a remote location.

[0022] The above summary of some examples and embodiments is not intended to describe each or all of the embodiments disclosed in this disclosure. The following brief and detailed descriptions of the drawings are illustrative of these embodiments more specifically, but are also illustrative and not limiting.

[0023] This disclosure can be understood in more detail by considering the following detailed description of various embodiments relating to the attached drawings. [Brief explanation of the drawing]

[0024] [Figure 1] This is a schematic perspective view showing a portion of a human eye and a portion of an ophthalmic implant placed within Schlemm's canal. [Figure 2] Figure 1 is an enlarged perspective view showing a portion of the implant. [Figure 3] Figures 1 and 2 are perspective views showing the volume defined by the body of the ophthalmic implant. [Figure 4] This is a perspective view showing the first surface that intersects with the main body of the ophthalmic implant. [Figure 5] This is a perspective view showing the bending moment applied to ophthalmic implants. [Figure 6] Figure 5 is a plan view of the implant, but the bending moment is not indicated. [Figures 7A-7B] Figure 7A is a lateral cross-sectional view of the ophthalmic implant shown in Figure 6, taken along the cross-sectional line AA in Figure 6, and Figure 7B is a lateral cross-sectional view of the ophthalmic implant shown in Figure 6, taken along the cross-sectional line BB in Figure 6. [Figure 8] This is an enlarged cross-sectional view of the ophthalmic implant shown in Figure 6, taken along the cross-sectional line BB in Figure 6. [Figure 9] This is an enlarged cross-sectional view of the ophthalmic implant shown in Figure 6, taken along the cross-sectional line AA in Figure 6. [Figure 10A] This is a magnified perspective view of a portion of an ophthalmic implant, including a pressure sensor. [Figure 10B]Figure 10A is a cross-sectional view of an exemplary pressure sensor taken along line BB. [Figure 10C] This is a magnified perspective view of another part of the ophthalmic implant, including the pressure sensor. [Figure 11] This is a schematic diagram of an electronic device that receives data from an implanted eye implant. [Figure 12] This is a plan view showing an ophthalmic implant according to another embodiment of the present invention, having a longitudinal radius of curvature that changes along its length. [Figure 13] This is a perspective view showing an ophthalmic implant according to yet another embodiment of the present invention, which substantially has no radius of curvature. [Figure 14] This is a schematic diagram of the medical procedure to be followed according to this detailed explanation. [Figure 15] Figure 14 is an enlarged perspective view further showing the delivery system and the eye. [Figures 16A-16B] Figure 16A is a perspective view showing a delivery system including an ophthalmic implant and a cannula defining a passage sized to slidably receive the ophthalmic implant, and Figure 16B is a magnified detail view further showing the ophthalmic implant and cannula 108 shown in Figure 6A. [Figure 17] A perspective view of the cannula, following the detailed explanation. [Figure 18] Figure 17 is a perspective view of an assembly including a cannula and an ophthalmic implant located within the passage defined by the cannula. [Figure 19] Figure 18 is a schematic perspective view including the assembly shown. [Figure 20] Figure 19 is an enlarged perspective view showing a portion of the cannula within the assembly. [Figure 21] This is an additional perspective view showing the ophthalmic implant and cannula shown in Figure 20 above. [Figure 22] Figure 21 is an additional perspective view showing the ophthalmic implant and cannula. [Figure 23] Figures 21 and 22 show additional perspective views of ophthalmic implants and cannulas. [Figure 24] Figure 23 is a perspective view of Schlemm's canal after the cannula has been withdrawn, leaving the entrance portion of the ophthalmic implant in the anterior chamber and the remaining portion of the implant in Schlemm's canal. [Figures 25A-25B] Figure 25A is a perspective view showing another exemplary delivery system including an ophthalmic implant and a cannula defining a passage sized to slidably receive the ophthalmic implant, and Figure 25B is a magnified detail view further showing the ophthalmic implant and cannula shown in Figure 25A. [Figure 26] Figure 25 is a more enlarged and detailed view showing the delivery system and the eye. [Figure 27] Figure 25 is a perspective view further showing the delivery system. [Figure 28] Figure 25 is a side view showing the cannula in more detail. [Figure 28A] Figure 25 is an additional side view showing the cannula. [Figure 29] Figure 25 is a more enlarged and detailed view of the cannula shown in Figure 25. [Figure 30] Figure 25 is a magnified and detailed view showing the tip of the cannula. [Modes for carrying out the invention]

[0025] While this disclosure can be modified into various forms of alteration and alternatives, specific examples are shown in the drawings and described in more detail therein. However, it should be understood that the invention is not limited to the specific embodiments described. On the contrary, the invention encompasses all modifications, equivalents, and alternatives that fall within the spirit and scope of this disclosure.

[0026] The following description should be understood with reference to the drawings, which are not necessarily to a constant scale, and similar reference numbers in some figures indicate similar elements. Those skilled in the art will recognize that the various elements described and / or shown may be composed of various combinations and configurations without departing from the scope of this disclosure. The detailed description and drawings illustrate exemplary embodiments of the claimed invention.

[0027] Definitions of specific terms are provided below. These definitions apply unless different definitions are given in the claims or elsewhere in this specification. All numerical values ​​herein, whether expressly indicated or not, are to be considered qualified with the term “approximately.” The term “approximately” generally refers to a range of numbers that a person skilled in the art could consider equivalent to (i.e., having the same or substantially the same function or result as) the value shown. Often, the term “approximately” may include numbers rounded to the nearest significant figure. Other uses of the term “approximately” (i.e., related to non-numerical terms) are to be considered to have their own general and customary definitions that are understood in relation to and consistent with this specification, unless otherwise noted.

[0028] Listing numerical ranges by endpoints includes all numbers within that range (for example, 1-5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). As used herein and in the appended claims, the singular “one” and “it” include or refer to singular and plural subjects, respectively, unless otherwise specified. As used herein and in the claims, the term “or” is generally used to include “and / or,” unless otherwise specified.

[0029] References to “certain embodiments,” “several embodiments,” and “other embodiments” in this specification should be noted as indicating that while the described embodiments may include certain features, structures, or characteristics, not all embodiments necessarily include those features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same embodiments. Moreover, if certain features, structures, or characteristics are described in relation to a particular embodiment, it will be apparent to those skilled in the art that such features, structures, or characteristics will be affected in relation to other embodiments, whether or not they are explicitly stated otherwise. In other words, each of the various elements described below, even if not explicitly shown in a particular combination, can be conceivably combined or configured with each other to form other additional embodiments or to perform and / or enhance the described embodiments, as can be understood by those skilled in the art.

[0030] The following detailed description should be understood with reference to the drawings, where similar elements in different drawings are identified by the same reference number. Each drawing is not necessarily to a constant scale, but illustrates exemplary embodiments and is not intended to limit the scope of this disclosure.

[0031] Figure 1 is a schematic perspective view showing a portion of a human eye 20. The eye 20 is conceptualized as a fluid-filled sphere having two chambers. The sclera 22 of the eye 20 surrounds the posterior chamber 24, which is filled with a viscous fluid known as vitreous humor. The cornea 26 of the eye 20 encloses the anterior chamber 30, which is filled with a fluid known as aqueous humor. The cornea 26 is in contact with the sclera 22 at the edge 28 of the eye 20. The lens 32 of the eye 20 is located between the anterior chamber 30 and the posterior chamber 24. The lens 32 is held in place by numerous ciliary zonules 34. Whenever a human being looks at an object, they are seeing the object through the cornea, aqueous humor, and lens of the eye. Because they are transparent, the cornea and lens do not contain blood vessels. Therefore, blood does not flow through the cornea and lens to nourish these tissues and remove waste products from them. Instead, these functions are performed by the aqueous humor. The continuous flow of aqueous humor through the eye nourishes the parts of the eye that lack blood vessels (e.g., the cornea and lens). This flow of aqueous humor also removes waste products from these tissues.

[0032] Aqueous humor is produced by an organ known as the ciliary body. The ciliary body contains epithelial cells that continuously secrete aqueous humor. In a healthy eye, the flow of aqueous humor is interrupted when new aqueous humor is secreted by the epithelial cells of the ciliary body. This excess aqueous humor enters the bloodstream and is carried away by venous blood leaving the eye.

[0033] In a healthy eye, aqueous humor flows out of the anterior chamber 30 through the trabecular network 36 and enters Schlemm's canal 38, located on the outer edge of the iris 42. The aqueous humor exits Schlemm's canal 38 by flowing through numerous outlets 40. After leaving Schlemm's canal 38, the aqueous humor is absorbed into the venous blood flow.

[0034] In Figure 1, the ophthalmic implant 100 is positioned within Schlemm's canal 38 of the eye 20. The ophthalmic implant 100 has a body 102 which includes a plurality of tissue support frames 104 and a plurality of vertebrae 106. The body 102 also includes a first edge 120 and a second edge 122 which define a first opening 124. The first opening 124 is formed as a groove and is in fluid communication with an elongated flow channel 126 defined by the inner surface 128 of the body 102. Referring to Figure 1, it can be seen that the first opening 124 is located on the outside 130 of the body 102. Thus, the flow channel 126 opens radially outward in a direction 132 through the first opening 124.

[0035] The ophthalmic implant 100 may be inserted into Schlemm's canal of a human eye to facilitate the flow of aqueous humor out of the anterior chamber. This flow includes an axial flow along Schlemm's canal, flowing in from the anterior chamber into Schlemm's canal and out of Schlemm's canal via an outlet communicating with Schlemm's canal. When in place within the eye, the ophthalmic implant 100 supports the trabecular reticular tissue and Schlemm's canal tissue, providing improved communication between the anterior chamber and Schlemm's canal (via the trabecular reticular

[0036] Figure 2 is an enlarged perspective view showing a portion of the ophthalmic implant 100 shown in the previous figure. The ophthalmic implant 100 has a main body 102 extending along a generally curved longitudinal axis 134. The main body 102 has a plurality of tissue support frames 104 and a plurality of spines 106. As shown in Figure 2, these spines 106 and frames 104 are arranged in a repeating AB pattern where each A is a tissue support frame and each B is a spine. In the embodiment of Figure 2, one spine extends between each adjacent pair of frames 104.

[0037] The frame 104 of the main body 102 includes a first frame 136 of the ophthalmic implant 100 positioned between the first vertebra 140 and the second vertebra 142. In the embodiment of Figure 2, the first frame 136 is formed as a first support 144 extending between the first vertebra 140 and the second vertebra 142. The first frame 136 also includes a second support 146 extending between the first vertebra 140 and the second vertebra 142. In the exemplary embodiment of Figure 2, each support is circumferentially wavy when extending longitudinally between the first vertebra 140 and the second vertebra 142.

[0038] In the embodiment shown in Figure 2, the body 102 has a longitudinal radius of 150 and a transverse radius of 148. The body 102 of the ophthalmic implant 100 includes a first edge 120 and a second edge 122 that define a first opening 124. The first opening 124 is in fluid communication with a longitudinal flow path 126 defined by the inner surface 128 of the body 102. The second opening 138 is defined by the second edge 122A of the first support 144 and the second edge 122B of the second support 146. The additional openings defined by the first opening 124, the second opening 138 and the ophthalmic implant 100 allow aqueous humor to flow transversely across and / or through the ophthalmic implant 100. The outer surface of the body 102 defines a volume 152.

[0039] Figure 3 is an additional perspective view showing the volume 152 defined by the body of the ophthalmic implant shown in the previous figure. Referring to Figure 3, it will be understood that the volume 152 extends along a generally curved longitudinal axis 134. The volume 152 has a longitudinal radius 150, a transverse radius 148, and a substantially circular transverse cross-section 153.

[0040] Figure 4 is a perspective view showing a first plane 154 and a second plane 155 intersecting the ophthalmic implant 100. In Figure 4, the first plane 154 is depicted with diagonal lines. Referring to Figure 4, it will be understood that the spines 106 of the main body 102 are generally aligned with one another, and the first plane 154 intersects all of the spines 106 shown in Figure 4. In the embodiment of Figure 4, the main body 102 of the ophthalmic implant 100 is generally symmetrical with respect to the first plane 154.

[0041] In the embodiment shown in Figure 4, the flexibility of the main body 102 is maximum when the main body 102 is bent along the first plane 154, and the flexibility of the main body 102 is low when it is bent along a plane other than the first plane 154 (for example, a plane intersecting the first plane 154). For example, in the embodiment shown in Figure 4, when the main body 102 is bent along the second plane 155, it has a second flexibility that is lower than the first flexibility that the main body 102 has when bent along the first plane 154.

[0042] In other words, in the embodiment shown in Figure 4, the bending modulus of the main body 102 is minimum when the main body 102 is bent along the first plane 154. The main body 102 has a first bending modulus when bent along the first plane 154, and a higher bending modulus when bent along a plane other than the first plane 154 (for example, a plane intersecting the first plane 154). For example, in the embodiment shown in Figure 4, when the main body 102 is bent along the second plane 155, it has a second bending modulus that is higher than the first bending modulus that the main body 102 has when bent along the first plane 154.

[0043] Figure 5 is an enlarged perspective view showing a portion of the ophthalmic implant 100 shown in the previous figure. In the exemplary embodiment of Figure 5, a bending moment M is applied to the body 102 of the ophthalmic implant 100. The bending moment M acts around a first axis 156 which is substantially perpendicular to the first plane 154. A second axis 158 and a third axis 160 are also shown in Figure 5. The second axis 158 is substantially perpendicular to the first axis 156. The third axis 160 is inclined with respect to the first axis 156.

[0044] The inner surface 128 of the main body 102 defines a flow path 126. The main body 102 of the ophthalmic implant 100 includes a first edge 120 and a second edge 123 that define a first opening 124. The flow path 126 of the ophthalmic implant 100 is in fluid communication with the first opening 124. The second opening 138 is defined by the second edge 122A of the first support 144 and the second edge 122B of the second support 146. The additional openings defined by the first opening 124, the second opening 138 and the ophthalmic implant 100 allow aqueous humor to flow laterally across and / or through the ophthalmic implant 100.

[0045] As shown in Figure 5, the ophthalmic implant 100 has a first spine 140 and a second spine 142. The first support 144 and the second support 146 form the first frame 136 of the ophthalmic implant 100, which extends between the first spine 140 and the second spine 142. In the exemplary embodiment of Figure 5, each support is circumferentially wavy when it extends longitudinally between the first spine 140 and the second spine 142.

[0046] In the embodiment shown in Figure 5, the flexibility of the body 102 is maximized when the body 102 is bent by a moment acting around the first axis 156, and the body 102 has lower flexibility when bent by a moment acting around an axis other than the first axis 156 (e.g., the second axis 158 and the third axis 160). In other words, the bending modulus of the body 102 is minimized when the body 102 is bent by a moment acting around the first axis 156, and the body 102 has a higher bending modulus when bent by a moment acting around an axis other than the first axis 156 (e.g., the second axis 158 and the third axis 160).

[0047] Figure 6 is a plan view showing the ophthalmic implant 100 shown in the previous figure. In the embodiment of Figure 6, no external force acts on the body 102 of the ophthalmic implant 100, and the body 102 can freely take on the generally curved resting shape shown in Figure 6. The body 102 defines a first opening 124 located on the outer surface 130 of the body 102. A flow path 126 is defined by the inner surface of the body 102 and opens radially outward 132 through the first opening 124. The proximal end 101 of the ophthalmic implant 100 may include a locking portion configured to mate and / or engage with a complementary locking portion of a delivery tool. Section lines AA and BB can be seen in Figure 6. Section line AA intersects the first frame 136 of the ophthalmic implant 100. Section line BB intersects the first spine 140 of the ophthalmic implant 100.

[0048] Figure 7A is a transverse cross-sectional view of the ophthalmic implant 100 along the section line AA shown in the previous figure. Section line AA intersects the first and second supports 144 and 146 of the first frame 136 at the point where the circumferential undulation of these supports is maximum. The body 102 of the ophthalmic implant 100 has a longitudinal radius 150 and a transverse radius 148. The inner surface 128 of the body 102 defines a flow path 126. The first opening 124 is in fluid communication with the flow path 126.

[0049] In Figure 7A, it can be seen that the first opening 124 of the main body 102 extends between the first edge 120A of the first support column 144 and the first edge 120B of the second support column 146. Referring to Figure 7A, it will be understood that the second support column 146 has a shape that is a mirror image of the shape of the first support column 144.

[0050] Figure 7B is a transverse cross-sectional view of the ophthalmic implant 100 along the cutting line BB shown in the previous figure. The cutting line BB intersects the first spine 140 of the ophthalmic implant 100. The body 102 has a longitudinal radius 150 and a transverse radius 148. In the embodiment of Figure 7B, the center 159 of the transverse radius 148 and the center 163 of the longitudinal radius 150 are located on either side of the first spine 140. The center 159 of the transverse radius 148 is located on the first side of the first spine 140. The center 163 of the longitudinal radius 150 is located on the second side of the second spine 142.

[0051] Figure 8 is an enlarged cross-sectional view of the ophthalmic implant 100 along the cutting line BB of Figure 6. The first vertebra 140 includes a first principal surface 161, a second principal surface 162, a first secondary surface 164, and a second secondary surface 166. Referring to Figure 8, it will be understood that the first principal surface 161 includes a concave surface 168. The second principal surface 162 is opposite the first principal surface 161. In the embodiment of Figure 8, the second principal surface 162 includes a convex surface 170.

[0052] The geometric shape of the spine provides the ophthalmic implant with a flexible property that can facilitate the advancement of the ophthalmic implant into Schlemm's canal. In the embodiment of Figure 8, the first spine 140 has a thickness T1 extending between the first main surface 161 and the second main surface 162. Also in the embodiment of Figure 8, the first spine 140 has a width W1 extending between the first secondary surface 164 and the second secondary surface 166.

[0053] In some useful embodiments, the spine of the ophthalmic implant according to this detailed description has an aspect ratio of width W1 to thickness T1 greater than about 2. In some particularly useful embodiments, the spine of the ophthalmic implant according to this detailed description has an aspect ratio of width W1 to thickness T1 greater than about 4. In one useful embodiment, the ophthalmic implant has a spine having an aspect ratio of width W1 to thickness T1 of about 5.2.

[0054] The first axis 156, the second axis 158, and the third axis 160 are shown in Figure 8. The second axis 158 is approximately perpendicular to the first axis 156. The third axis 160 is inclined relative to the first axis 156.

[0055] In the embodiment shown in Figure 8, the flexibility of the first spine 140 is maximized when the first spine 140 is bent by a moment acting around the first axis 156. The first spine 140 has a first degree of flexibility when bent by a moment acting around the first axis 156, and lower flexibility when bent by a moment acting around an axis other than the first axis 156 (e.g., a second axis 158 and a third axis 160). For example, the first spine 140 has a second degree of flexibility when bent by a moment acting around the second axis 158 shown in Figure 8. This second degree of flexibility is lower than the first degree of flexibility the first spine 140 has when bent by a moment acting around the first axis 156.

[0056] In the embodiment shown in Figure 8, the flexural modulus of the first spine 140 is minimized when the first spine 140 is bent by a moment acting around the first axis 156. The first spine 140 has a first flexural modulus when bent by a moment acting around the first axis 156, and a higher flexural modulus when bent by a moment acting around an axis other than the first axis 156 (e.g., a second axis 158 and a third axis 160). For example, the first spine 140 has a second flexural modulus when bent by a moment acting around the second axis 158 shown in Figure 8. This second flexural modulus is higher than the first flexural modulus that the first spine 140 has when bent by a moment acting around the first axis 156.

[0057] Figure 9 is an enlarged cross-sectional view of the ophthalmic implant 100 along the cutting line AA of Figure 6. The cutting line AA intersects the first support 144 and the second support 146 at the point where the circumferential undulation of these supports is greatest.

[0058] Each support shown in Figure 9 includes a first main side surface 161, a second main side surface 162, a first secondary side surface 164, and a second secondary side surface 166. Referring to Figure 9, it will be understood that each first main side surface 161 includes a concave surface 168, and each second main side surface 162 includes a convex surface 170.

[0059] In the embodiment shown in Figure 9, each support has a thickness T2 extending between a first main surface 161 and a second main surface 162. Also in the embodiment shown in Figure 9, each support has a width W2 extending between a first secondary surface 164 and a second secondary surface 166. In some useful embodiments, the ophthalmic implant according to this detailed description includes a spine having a width W1 that exceeds the width W2 of the support of the ophthalmic implant.

[0060] In some useful embodiments, the struts of the ophthalmic implant according to this detailed description have an aspect ratio of width W2 to thickness T2 greater than about 2. In some particularly useful embodiments, the struts of the ophthalmic implant according to this detailed description have an aspect ratio of width W2 to thickness T2 greater than about 4. One exemplary ophthalmic implant has a strut having an aspect ratio of width W2 to thickness T2 of about 4.4.

[0061] The body 102 of the ophthalmic implant 100 has a longitudinal radius of 150 and a transverse radius of 148. In some useful embodiments, the ophthalmic implant according to this detailed description is sufficiently flexible to take shape to match the longitudinal curvature of Schlemm's canal when the ophthalmic implant is advanced into the eye. Also in some useful embodiments, the length of the ophthalmic implant is selected so that when the ophthalmic implant is placed in Schlemm's canal, the ophthalmic implant extends over a pre-selected angular span. Examples of pre-selected angular spans that may be suitable for several applications include 60°, 90°, 150°, and 180°. The diameter of the ophthalmic implant according to this detailed description may be selected so that the ophthalmic implant lies within Schlemm's canal and supports it. In some useful embodiments, the diameter of the ophthalmic implant ranges from about 0.005 inches (0.127 mm) to about 0.04 inches (1.016 mm). In some particularly useful embodiments, the diameter of the ophthalmic implant ranges from approximately 0.005 inches (0.127 millimeters) to approximately 0.02 inches (0.508 millimeters).

[0062] It should be understood that ophthalmic implants described in this detailed explanation may be straight or curved. If an ophthalmic implant is curved, it may have a substantially uniform longitudinal radius over its entire length, or the longitudinal radius of the ophthalmic implant may vary along its length. Figure 6 shows an example of an ophthalmic implant with a substantially uniform radius of curvature. Figure 10 shows an example of an ophthalmic implant with a longitudinal radius of curvature that varies along its length. An example of a substantially straight ophthalmic implant is shown in Figure 13.

[0063] Figure 10A is an enlarged perspective view showing a portion of the ophthalmic implant 100 shown in Figures 2 and 4. The ophthalmic implant 100 may further include an intraocular pressure sensor 180, as shown in detail A, mounted on the inner surface 128 of the ophthalmic implant 100 adjacent to the exit of the implant 100. Although the pressure sensor 180 is shown mounted on the inner surface 128 of the ophthalmic implant 100, it is assumed that, if necessary, the pressure sensor 180 may be located within one of the openings 124, 138 or on the outer surface of the ophthalmic implant 100. Once the ophthalmic implant 100 is implanted, the pressure sensor 180 can continuously measure the patient's intraocular pressure.

[0064] The pressure sensor 180 may be a micro-electromechanical system (MEMS) pressure sensor. While the pressure sensor 180 is described as a MEMS pressure sensor, it is assumed that other pressure sensors may be used instead of or in addition to the MEMS pressure sensor. In some examples, the pressure sensor 180 may have a width in the range of approximately 0.02 millimeters (20 micrometers) to approximately 1.0 millimeter. However, it is assumed that the pressure sensor 180 is smaller than 0.02 millimeters (20 micrometers) or larger than 1.0 millimeter. In some examples, the pressure sensor 180 may have a width dimension in the nanometer range. Furthermore, although only one pressure sensor 180 is shown, the ophthalmic implant 100 may contain two or more pressure sensors 180 as needed. For example, the first pressure sensor may be located at the first end of the ophthalmic implant 100, and the second pressure sensor may be located at the second end of the ophthalmic implant. In some examples, the pressure sensor 180 may be located in a channel 128 adjacent to the proximal end 101 of the implant 100, as shown in Figure 10C. The pressure sensor 180 may include, but is not required, a protective cover to prevent the delivery device (not expressly shown) from damaging the sensor 180 during delivery of the ophthalmic implant 100.

[0065] MEMS pressure sensors are often formed by anisotropically etching a recess toward the back side of a die in a silicon substrate, leaving a thin, flexible diaphragm 182. During use, at least one surface of the diaphragm 182 is exposed to input pressure (e.g., intraocular pressure). The diaphragm 182 flexes in response to the magnitude of the input pressure, which can be detected by one or more electrical components or sensor elements 186 (e.g., piezo resistors) placed on or embedded in the diaphragm 182. Changes in the resistance of the piezo resistor 186 are reflected as changes in the output voltage signal from the resistance bridge at least partially formed by the piezo resistor. In some examples, the diaphragm can be made thinner by adding support bosses, which may facilitate increased sensitivity of the diaphragm compared to a flat diaphragm. Circuit elements may be connected to the sensor element 186 to provide some level of signal processing before providing an output signal to the bond pad 188 of the pressure sensor 180. This signal processing can filter, amplify, linearize, calibrate, and / or otherwise process the raw sensor signal generated by the sensor element (e.g., a piezoristor 186). Although the sensor element 186 is described as a piezoristor, it is assumed that the sensor element may be selected to provide a capacitive pressure sensor 180.

[0066] The pressure sensor 180 may include a first substrate 185 and a second substrate 183, as shown in Figure 10B, which is a cross-section of an exemplary pressure sensor 180 taken along line BB in Figure 10A. In some examples, the first substrate 185 may be a layered silicon-insulator-silicon substrate or wafer formed using silicon-on-insulator (SOI) technology, although this is not required. Other substrates may be used as needed. The first substrate 185 may include a first silicon layer. An insulating layer or oxide layer 187 may be disposed on the first silicon layer 185. In some examples, the insulating layer 187 may be formed from silicon dioxide, silicon nitride, sapphire, and / or any other suitable insulating material. Although not explicitly shown, the pressure sensor 180 may include a second silicon layer disposed on the insulating layer. In some examples, the second silicon layer may be thinned or removed so that the oxide layer 187 is exposed on the side facing away from the second substrate 183. Alternatively, and in some examples, the second silicon layer and oxide layer 187 are not provided from the beginning.

[0067] The second substrate 183 can be any semiconductor wafer (e.g., silicon or germanium) or other substrate as needed. It is conceivable that either or both of the first substrate 185 or the second substrate 183 may be doped with impurities to provide an n-type or p-type external semiconductor. For example, the first substrate 185 may be an n-type substrate and the second substrate 183 may be a p-type substrate. The reverse configuration is also conceivable, or both substrates may be doped to the same polarity. In some examples, the first substrate 185 and / or the second substrate 183 may include an epitaxial layer.

[0068] A portion of the first substrate 185, such as a portion of the first silicon layer, may be removed, leaving a thin flexible diaphragm 182 over a cavity or recess 181. In some examples, a piezo resistor 186 may be positioned inside or on the diaphragm 182 to measure the deflection / stress of the diaphragm 182 in order to form a pressure sensor. During use, at least one surface of the diaphragm 182 may be exposed to an input pressure. The diaphragm 182 can then bend in proportion to the magnitude of the pressure applied to it. The deflection of the diaphragm 182 then results in a change in the resistance of the piezo resistor 186. The change in the resistance of the piezo resistor 186 may be reflected as a change in the output voltage signal of a resistive bridge formed at least partially by the piezo resistor 186. The output voltage provides a measure of the input pressure applied to the diaphragm 182.

[0069] The second substrate 183 is expected to be flexible so as to allow the substrate 183 to be mounted flush with the inner surface 128 of the ophthalmic implant 100. Alternatively or additionally, the second substrate 183 may have a curved outer surface (facing away from the diaphragm 182) that is shaped to substantially match the curved inner surface 128 of the ophthalmic implant 100. The material forming the pressure sensor 180 is expected to be selected so that the pressure sensor 180 is biocompatible.

[0070] As described above, the pressure sensor 180 is described as a MEMS pressure sensor, but it is assumed that the pressure sensor 180 may take other suitable forms. In one alternative example, the pressure sensor can be formed in such a way that radio waves can be used to detect changes in pressure without a sensor element incorporated into the device. Such a pressure sensor may include a flexible base substrate, a bottom induction coil disposed on the base substrate, a pressure-sensitive rubber pyramid layer disposed on the bottom induction coil, an upper induction coil disposed on top of the rubber pyramid, and an upper substrate disposed on top of the upper induction coil. When pressure is applied to the sensor, the induction coils move closer to each other. Radio waves reflected by the induction coils (from the applied source) have a lower resonant frequency if the coils are placed closer together. Thus, the frequency of the radio waves can indicate the distance between the coils, which is then correlated with the pressure applied to the device.

[0071] The pressure sensor 180 may further comprise an antenna or inductor 184 to enable wireless communication of data from the pressure sensor 180 to a reading device. In some examples, if it is desired that the pressure sensor 180 transmit data from the pressure sensor 180 to another device located outside the body, radio frequency communication protocols such as cellular communication, ZigBee®, Bluetooth®, Wi-Fi®, IrDA, dedicated short-range communication (DSRC), EnOcean®, or any other suitable radio protocol may be used. The data may be transmitted to any number of such appropriately enabled devices, including but not limited to specially designed devices such as mobile phones, tablets or laptop computers, desktop computers, portable handheld devices, personal digital assistants (PDAs), or medical devices. This may enable physicians, patients, or other parties to monitor intraocular pressure without using a tonometer. In some cases, pressure data may be automatically transmitted from a remote device to a physician. For example, once an ocular implant 100 equipped with a pressure sensor 180 is implanted, an enabled remote device 192 can be placed within communication range of the patient's eye, as shown in Figure 11. This may allow the enabled device 192 to receive intraocular pressure data recorded by the pressure sensor 180. The enabled device 192 may be configured to automatically transmit the data to a physician, for example, a second remote device.

[0072] Figure 12 is a plan view showing an ophthalmic implant 200 having a radius of curvature that varies along its length. The proximal end 201 of the ophthalmic implant 200 may include a reciprocating portion configured to mate and / or engage with a complementary reciprocating portion of a delivery tool. In the embodiment of Figure 12, the ophthalmic implant 200 has a generally curved resting state. This resting state can be established, for example, by using a heat-setting process. The shape of the ophthalmic implant shown in Figure 12 includes a tip radius RA, a proximal radius RC, and a mid-radius RB. In the embodiment of Figure 12, the tip radius RA is greater than both the mid-radius RB and the proximal radius RC. Also in the embodiment of Figure 12, the mid-radius RB is greater than the proximal radius RC and smaller than the tip radius RA. In one useful embodiment, the tip radius RA is approximately 0.320 inches (8.128 millimeters), the mid-range radius RB is approximately 0.225 inches (5.715 millimeters), and the base radius RC is approximately 0.205 inches (5.207 millimeters).

[0073] In the embodiment shown in Figure 12, the tip portion of the ophthalmic implant follows an arc extending over angle AA. The proximal portion of the ophthalmic implant follows an arc extending over angle AC. The intermediate portion of the ophthalmic implant is located between the tip and proximal portions. The intermediate portion extends over angle AB. In one useful embodiment, angle AA is approximately 55 degrees, angle AB is approximately 79 degrees, and angle AC is approximately 60 degrees.

[0074] The ophthalmic implant 200 may be used in combination with a method for treating the eye of a human patient for a disease and / or disorder (e.g., glaucoma). Some such methods may include the step of inserting a core member into a lumen defined by the ophthalmic implant 200. The core member may include, for example, a wire or a tube. The tip of the ophthalmic implant can be inserted into Schlemm's canal. The ophthalmic implant and core member can then be advanced into Schlemm's canal until the ophthalmic implant reaches a desired position. In some embodiments, the inlet portion of the implant may be located in the anterior chamber, while the rest of the implant extends into Schlemm's canal through a trabecular network. The core member can then be withdrawn from the ophthalmic implant, leaving the implant in place and supporting the tissue forming Schlemm's canal. Further details of the ophthalmic implant delivery system can be found in U.S. Patent Application No. 11 / 943,289, filed November 20, 2007, now U.S. Patent No. 8,512,404, the disclosures of which are incorporated herein by reference.

[0075] The flexibility and flexural modulus characteristics of the ophthalmic implant of the present invention facilitate ensuring the proper orientation of the implant within Schlemm's canal. Figure 1 shows the desired orientation of the opening 124 when the implant 100 is placed within Schlemm's canal. As shown in the figure, the opening 124 faces radially outward. Thus, the implant 100 is designed to be maximally flexible when bent along a plane defined by the longitudinal axis of the implant 100, as shown in Figure 1, and less flexible when bent along other planes, thereby allowing the curved shape of Schlemm's canal to automatically position the implant in the desired orientation if the implant is initially placed within Schlemm's canal in a different orientation.

[0076] Figure 13 is a perspective view showing an ophthalmic implant 300 according to an additional embodiment described in detail in the present invention. Referring to Figure 13, it will be understood that the ophthalmic implant 300 has a generally linear resting (i.e., stress-free) shape. The ophthalmic implant 300 extends along a generally linear longitudinal axis 334. In some useful embodiments, the ophthalmic implant 300 is sufficiently flexible to take on a curved shape when advanced into Schlemm's canal of the eye.

[0077] The ophthalmic implant 300 includes a body 302. Referring to Figure 13, it will be understood that the body 302 includes a plurality of tissue support frames 304 and a plurality of vertebrae 306. As shown in Figure 13, these vertebrae 306 and frames 304 are arranged in an alternating pattern in which one vertebra extends between each adjacent pair of frames 304. The frames 304 of the body 302 include a first frame 336 of the ophthalmic implant 300, which is positioned between a first vertebra 340 and a second vertebra 342. In the embodiment of Figure 13, the first frame 336 includes a first support 344 that extends between the first vertebra 340 and the second vertebra 342. A second support 346 of the first frame also extends between the first vertebra 340 and the second vertebra 342. Each support column is circumferentially wavy when it extends longitudinally between the first vertebra 340 and the second vertebra 342.

[0078] The inner surface 328 of the main body 302 defines a flow path 326. The main body 302 of the ophthalmic implant 300 includes a first edge 320 and a second edge 322 that define a first opening 324. The flow path 326 of the ophthalmic implant 300 is in fluid communication with the first opening 324. The first support column 344 of the first frame 336 includes a first edge 325A. The second support column 346 has a first edge 325B. In Figure 13, it can be seen that the first opening 324 of the main body 302 extends between the first edge 325A of the first support column 344 and the first edge 325B of the second support column 346.

[0079] The first axis 356, the second axis 358, and the third axis 360 are shown in Figure 13. The second axis 358 is approximately perpendicular to the first axis 356. The third axis 360 is approximately inclined with respect to the first axis 356. The flexibility of the body 302 is maximum when the body 302 is bent by a moment acting around the first axis 356, and the body 302 has lower flexibility when bent by moments acting around axes other than the first axis 356 (e.g., the second axis 358 and the third axis 360). In other words, in the embodiment shown in Figure 13, the bending modulus of the body 302 is minimal when the body 302 is bent by a moment acting around the first axis 356, and the body 302 has a higher bending modulus when bent by a moment acting around axes other than the first axis 356 (e.g., the second axis 358 and the third axis 360).

[0080] The ophthalmic implant 300 may further include an intraocular pressure sensor 380 attached to the inner surface 328 of the ophthalmic implant 300. The pressure sensor 380 may be similar in shape and function to the pressure sensor 180 described above. Although the pressure sensor 380 is shown to be attached to the inner surface 328 of the ophthalmic implant 300, it is conceivable that the pressure sensor 380 may be attached in one of the openings 324 or on the outer surface of the ophthalmic implant 300, if necessary. The pressure sensor 380 can continuously measure the patient's intraocular pressure once the ophthalmic implant 300 is implanted.

[0081] The pressure sensor 380 may be a micro-electromechanical system (MEMS) pressure sensor. While the pressure sensor 380 is described as a MEMS pressure sensor, it is assumed that other pressure sensors may also be used instead of or in addition to MEMS pressure sensors. MEMS pressure sensors are often formed by anisotropically etching recesses into the back of a die on a silicon substrate, leaving a thin, flexible diaphragm. During use, at least one surface of the diaphragm is exposed to an input pressure (e.g., intraocular pressure). The diaphragm flexes in response to the magnitude of the input pressure, which can be detected by one or more electrical components or sensor elements (e.g., piezoristors) placed on or embedded in the diaphragm. Changes in the resistance of the piezoristor are reflected as changes in the output voltage signal from the resistance bridge at least partially formed by the piezoristor. In some examples, the diaphragm can be made thinner by adding support bosses, which may facilitate increased sensitivity of the diaphragm compared to a flat diaphragm. Before providing an output signal to the bond pad of the pressure sensor, circuit elements may be connected to the sensor element to provide some level of signal processing. This signal processing can involve filtering, amplifying, linearizing, calibrating, and / or otherwise processing the raw sensor signal generated by the sensor element (e.g., a piezoristor). Although the sensor element is described as a piezoristor, it is assumed that the sensor element may be selected to provide a capacitive pressure sensor 380.

[0082] The pressure sensor 380 may further include an antenna or inductor to enable wireless communication of data from the pressure sensor 380 to a reading device. In some examples, if it is desired to transmit data from the pressure sensor 380 to another device located outside the body, the pressure sensor 380 may use radio frequency communication protocols such as cellular communication, ZigBee®, Bluetooth®, Wi-Fi®, IrDA, Dedicated Short Range Communication (DSRC), EnOcean®, or any other suitable radio protocol, but is not limited to these. The data may be transmitted to any number of such appropriately enabled devices, including but not limited to mobile phones, tablet computers, computers, portable handheld devices, such as personal digital assistants (PDAs), or specially designed devices. This may enable physicians, patients, or other parties to monitor intraocular pressure without using a tonometer.

[0083] Figure 14 is a schematic representation of the medical procedure described in this detailed explanation. In the procedure in Figure 14, a physician is treating the eye 400 of patient P. In the procedure in Figure 14, the physician holds the handpiece of the delivery system 450 in his right hand RH. The physician's left hand (not shown) may be used to hold the handle H of the goniolens 402. Alternatively, some physicians may prefer to hold the delivery system handpiece in their left hand and the goniolens handle H in their right hand RH.

[0084] During the procedure shown in Figure 14, the physician can view the inside of the anterior chamber using a goniolens 402 and a microscope 404. Detail A in Figure 14 is a stylized simulation of the image the physician saw. The tip of the cannula 452 can be seen in Detail A. The shadow-like lines indicate the location of Schlemm's canal SC lying beneath the various tissues surrounding the anterior chamber (e.g., the trabecular meshwork). The tip opening 454 of the cannula 452 is positioned near Schlemm's canal SC in eye 400.

[0085] The method according to this detailed description may include the step of advancing the tip of cannula 452 through the cornea of ​​eye 400 so that the tip of cannula 452 is positioned within the anterior chamber. Cannula 452 may then be used to enter Schlemm's canal of the eye, for example, by penetrating the wall of Schlemm's canal with the tip of cannula 452. The tip opening 454 of cannula 452 may be in fluid communication with the lumen defined by Schlemm's canal. The ophthalmic implant can be advanced into Schlemm's canal from the tip opening 454. Insertion of the ophthalmic implant into Schlemm's canal may facilitate the flow of aqueous humor from the anterior chamber.

[0086] Figure 15 is an enlarged perspective view further showing the delivery system 450 and eye 400 shown in the previous figure. In Figure 15, the cannula 452 of the delivery system 450 is shown to extend through the cornea 426 of the eye 400. The tip portion of the cannula 452 is positioned inside the anterior chamber defined by the cornea 426 of the eye 400. In the embodiment of Figure 15, the cannula 452 is configured so that its tip opening 454 can be in fluid communication with Schlemm's canal.

[0087] In the embodiment shown in Figure 15, the ophthalmic implant is positioned within a passage defined by a cannula 452. The delivery system 450 includes a mechanism that allows the ophthalmic implant to be advanced and retracted along the length of the cannula 452. The ophthalmic implant may be positioned within the Schlemm's canal of the eye 400 by advancing the ophthalmic implant through the tip opening of the cannula 452 while the tip opening is in fluid communication with the Schlemm's canal.

[0088] Figure 16A is a perspective view showing a delivery system 500 including an ophthalmic implant 550 and a cannula 508 defining a passage sized to receive the ophthalmic implant 550 in a sliding manner. The delivery system 500 may be used to advance the ophthalmic implant 550 toward a target location within the patient's eye. Examples of target locations that may be appropriate in some applications include the Schlemm's canal, trabecular network, suprachoroidal space, and intra- and peri-anterior chamber regions of the eye. Figure 16B is a magnified detail view further showing the ophthalmic implant 550 and the cannula 508 of the delivery system 500.

[0089] The delivery system 500 in Figure 16A can control the advancement and retraction of the ophthalmic implant 550 within the cannula 508. The ophthalmic implant 550 can be positioned within a target location (e.g., Schlemm's canal) by advancing the implant through the tip opening 532 while the tip opening is in fluid communication with Schlemm's canal. In the embodiment of Figure 16A, the ophthalmic implant 550 is advanced through the tip opening 532 of the cannula 508 for illustrative purposes.

[0090] The delivery system 500 in Figure 16A includes a housing 502, a sleeve 504, and an end cap 510. A tracking wheel 506 extends through the wall of the housing 502 in Figure 16A. The tracking wheel 506 is part of a mechanism that allows the delivery tool 552 of the delivery system 500 to move forward and backward. The delivery tool 552 extends through the tip opening of the cannula 508 in Figure 16B. When the tracking wheel is rotated, the delivery tool 552 moves axially along the passage defined by the cannula 508. The axial direction can be the tip direction D or the proximal direction P. The delivery tool 552 and the mechanism for moving the delivery tool 552 are described in U.S. Patent Application No. 62 / 024,295, assigned to a common assignee, which is incorporated herein by reference.

[0091] In the embodiment shown in Figure 16A, the housing 502 is configured to be held in one hand while providing axial forward and backward control of the ophthalmic implant via the tracking wheel 506. The housing of the delivery system 500 results in a favorable ergonomic relationship of the fingers to the hand. This design provides a configuration that allows a user, such as a physician, to use part of their hand to stabilize the device while leaving the middle or index finger free to move independently from the rest of the hand. The middle or index finger can move independently and freely to rotate the wheel to advance and / or retract the ophthalmic implant.

[0092] Figure 16B is a magnified detail view further showing the cannula 508 of the ophthalmic implant 550 and delivery system 500. The cannula 508 includes a generally tubular member 598 having a proximal portion 540, an apical portion 534, and an apical portion 544 extending between the apical portion 534 and the proximal portion 540. In the embodiment of Figure 6, the apical portion 544 is curved. In some useful embodiments, the apical portion 544 is sized and configured to be received in the anterior chamber.

[0093] Figure 16B shows a delivery tool 552 of the delivery system 500 extending through the tip opening 532 of the cannula 508. The delivery tool 552 includes a mutual locking portion 560 configured to form a connection with a complementary mutual locking portion 562 of the ophthalmic implant 550, as will be described in more detail below. In the embodiment of Figure 16, as the tracking wheel is rotated, the delivery tool 552 and the ophthalmic implant 550 are moved along the path defined by the cannula 508. The cannula 508 is sized and configured so that its tip can be advanced through the trabecular network of the eye and into Schlemm's canal. Positioning the cannula 508 in this manner places its tip opening 532 in fluid communication with Schlemm's canal. The ophthalmic implant 550 can be positioned in Schlemm's canal by advancing the ophthalmic implant through the tip opening 532 of the cannula 508 while its tip opening is in fluid communication with Schlemm's canal. The tip of the cannula may include a cutting portion configured to cut through tissues such as the trabecular network and the walls of Schlemm's canal, for example, by providing a sharp edge at the tip 534 that is adapted to cut through such tissues.

[0094] Figure 17 is a perspective view of a cannula 508 according to a detailed description of the present invention. The cannula 508 in Figure 17 includes a generally tubular member 598 having a central axis 596. The generally tubular member 598 in Figure 17 includes a proximal portion 540, a distal portion 534, and an distal portion 544 extending between the distal portion 534 and the proximal portion 540. The distal opening surface 542 surrounds the distal opening 532, extending through the distal portion 534 and through the side wall of the cannula 508. An oblique edge 565 is positioned at the distal end of the distal opening surface 542 and extends from the distal portion 534 to the proximal end range 567 of the oblique edge 565. The tubular member 598 defines the distal opening 532, the proximal opening 536, and a passage 538 extending between the proximal opening 536 and the distal opening 532.

[0095] In the embodiment of Figure 17, the proximal portion 540 of the cannula 508 is substantially straight, and the anterior portion 544 of the cannula 508 is curved, with the central axis 596 defining a curved surface 548. The curved surface 548 is sometimes called the plane of curvature. The curved surface 548 divides the cannula 508 into a first portion PA and a second portion PB. In the embodiment of Figure 17, the second portion PB is substantially a mirror image of the first portion PA. In Figure 17, the anterior portion 544 is shown to extend between the anterior portion 534 and the proximal portion 540 without any intervening elements. In the embodiment of Figure 17, the anterior portion 544 is curved along its entire length.

[0096] The method described in this detail may include the step of advancing the tip 534 of the cannula 508 through the cornea of ​​the human eye so that the tip 534 is positioned within the anterior chamber. The cannula 508 can then be used to enter Schlemm's canal of the eye, for example, by penetrating the wall of Schlemm's canal using the tip 534 of the cannula 508. The oblique rim 565 may be inserted into Schlemm's canal to keep at least a portion of the tip opening 532 of the cannula 508 in communication with Schlemm's canal, as will be discussed in more detail below. The ophthalmic implant can be advanced into Schlemm's canal through the tip port of the cannula.

[0097] In the embodiment shown in Figure 17, the tip portion 544 of the cannula 508 defines a trough 554. In some useful embodiments, the trough 554 is configured to receive the entire outer cross-section of the ophthalmic implant as it is being advanced through Schlemm's canal. In this case, the trough 554 may have a depth dimension greater than the width of the ophthalmic implant. This cannula configuration advantageously prevents the ophthalmic implant from crossing the layers of the trabecular meshwork as it is being advanced through Schlemm's canal. The trough 554 may also be configured to allow the proximal portion of the ophthalmic implant to be released from the delivery tool, as will be discussed later.

[0098] The cannula 508 may further include a pressure sensor 580 positioned within the trough 554. The pressure sensor 580 may be similar in shape and function to the pressure sensor 180 described above. Although the pressure sensor 580 is shown mounted within the trough 554 of the cannula, it is conceivable that the pressure sensor 580 may be mounted within the cannula 508 or at other locations on the cannula 508. The pressure sensor 580 can provide immediate pressure readings during or immediately after implantation of the ophthalmic implant 550. In some examples, pressure readings obtained from the pressure sensor 580 on the cannula 508 can be compared with pressure readings obtained from a pressure sensor mounted on the ophthalmic implant 550, if provided in that manner.

[0099] The pressure sensor 580 may be a micro-electromechanical system (MEMS) pressure sensor. While the pressure sensor 580 is described as a MEMS pressure sensor, other pressure sensors may also be used instead of or in addition to the MEMS pressure sensor. Furthermore, although only one pressure sensor 580 is shown, the cannula 508 may contain two or more pressure sensors 580 as needed. MEMS pressure sensors are often formed by anisotropically etching a recess into the back of a die on a silicon substrate, leaving a thin, flexible diaphragm. During use, at least one surface of the diaphragm is exposed to an input pressure (e.g., intraocular pressure). The diaphragm flexes in response to the magnitude of the input pressure, which can be detected by one or more electrical components or sensor elements (e.g., piezoristors) positioned on or embedded in the diaphragm. Changes in the resistance of the piezoristor are reflected as changes in the output voltage signal from the resistance bridge at least partially formed by the piezoristor. In some examples, the diaphragm can be made thinner by adding support bosses, which may facilitate a higher sensitivity of the diaphragm than that of a flat diaphragm. Circuit elements may be connected so that the sensor element provides some level of signal processing before providing an output signal to the bond pad of the pressure sensor. This signal processing can involve filtering, amplifying, linearizing, calibrating, and / or otherwise processing the raw sensor signal generated by the sensor element (e.g., a piezoristor). Although the sensor element is described as a piezoristor, it is conceivable that the sensor element may be selected to provide a capacitive pressure sensor 580.

[0100] The pressure sensor 580 may further include an antenna or inductor to enable wireless communication of data from the pressure sensor 580 to a reading device. In some examples, if it is desired to transmit data from the pressure sensor 580 to another device located outside the body, the pressure sensor 580 may use radio frequency communication protocols such as cellular communication, ZigBee®, Bluetooth®, Wi-Fi®, IrDA, Dedicated Short Range Communication (DSRC), EnOcean®, or any other suitable radio protocol, but is not limited to these. The data may be transmitted to any number of such appropriately enabled devices, including but not limited to mobile phones, tablet computers, computers, portable handheld devices, such as personal digital assistants (PDAs), or specially designed devices. This may enable physicians, patients, or other parties to monitor intraocular pressure without using a tonometer.

[0101] Figure 18 is a perspective view of the assembly including the cannula 508 shown in the previous figure. For illustrative purposes, the cannula 508 is shown in cross-section in Figure 23. In Figure 18, the ophthalmic implant 550 can be seen to be placed within the passage 538 defined by the cannula 508. Referring to Figure 18, it will be understood that the tip portion 544 of the cannula 508 is curved such that the central axis 596 of the cannula 508 defines a curved surface 548. Referring to Figure 23, it will be understood that the curved surface 548 divides the cannula 508 into a first portion and a second portion PB. In the exemplary embodiment of Figure 18, only the second portion PB of the cannula 508 is shown.

[0102] Figure 19 is a schematic perspective view including the assembly shown in the previous figure. In the embodiment of Figure 19, the tip portion of a cannula 508 extending through the wall of Schlemm's canal SC is shown. The tip of the cannula 508 may include a sharp portion configured to cut and / or penetrate the columnar mesh and the wall of Schlemm's canal so that the passage defined by the cannula can be placed in fluid communication with the lumen defined by Schlemm's canal. Since the passage of the cannula is in fluid communication with the lumen of Schlemm's canal, the ophthalmic implant 550 can be advanced into Schlemm's canal from the tip opening of the cannula. In Figure 19, the tip portion of the ophthalmic implant 550 can be seen through the tip opening 532 of the cannula 508.

[0103] For illustrative purposes, a virtual window W is cut into the wall of the cannula 508 in Figure 19. The interlocking portion 560 of the delivery tool 552 and the complementary interlocking portion 562 of the ophthalmic implant 550 can be seen through the window W. In the embodiment of Figure 19, the interlocking portion 560 of the delivery tool 552 and the complementary interlocking portion 562 of the ophthalmic implant 550 engage with each other such that the proximal end 549 of the ophthalmic implant 550 is on the proximal side relative to the tip 551 of the delivery tool 552. The surface 561 of the delivery tool 552 rests on the wall of the cannula 508 so that the interlocking portion 560 of the delivery tool 552 and the complementary interlocking portion 562 of the ophthalmic implant 550 do not detach from each other. Once connected in this manner, the delivery tool 552 and the ophthalmic implant 550 move together as the delivery tool is advanced and retracted relative to the cannula 508 by the delivery system mechanism.

[0104] Figure 20 is an enlarged perspective view showing a portion of the cannula 508 shown in the previous figure. In some useful embodiments, the cannula 508 is curved to achieve substantially tangential entry into Schlemm's canal SC. In the embodiment of Figure 20, the cannula 508 is in contact with the outer main wall of Schlemm's canal at the contact point PT. Also in the embodiment of Figure 20, the curved tip portion of the cannula 508 is sized to be positioned within the anterior chamber.

[0105] As shown in Figure 20, the tip 534 and oblique margin of the cannula 508 are inserted into Schlemm's canal up to the proximal end range 567 of the oblique margin 565. At this position, the ophthalmic implant 550 extending into the trough 554 can be seen. In some useful embodiments, the ophthalmic implant has a radius of curvature larger than that of the cannula. This configuration ensures that the ophthalmic implant advances along the trough 554 as it is pushed apex-towards by the delivery system 500.

[0106] Figure 21 is an additional perspective view showing the ophthalmic implant 550 and cannula 508 shown in the previous figure. By comparing Figure 21 with the previous figure, it will be understood that the ophthalmic implant 550 is advanced in the apical direction D, while the cannula 508 remains stationary, thereby positioning the apical portion of the ophthalmic implant 550 within Schlemm's canal SC. The trough 554 opens into an elongated opening 532 defined by the edge 542 of the apical portion of the cannula 508. In the embodiment of Figure 21, the elongated opening defined by the cannula enables direct visualization of the ophthalmic implant as it advances within Schlemm's canal. The configuration that enables direct visualization of the ophthalmic implant has many clinical advantages. Monitoring the advancement of the implant by viewing it through a trabecular mesh during medical procedures is often difficult. For example, blood perfusion can push blood into Schlemm's canal, preventing the physician from seeing the portion of the implant that has entered the Schlemm's canal. Referring to Figure 21, the ophthalmic implant 550 advances along the trough 554 as it is advanced pteroarterially along the cannula 508. The trough opening allows the physician to monitor the advancement of the implant by viewing the implant structure as it advances through the trough before entering Schlemm's canal. The trough opening also allows the physician to locate the position of the tip of the ophthalmic implant relative to the incision made by the cannula to enter Schlemm's canal.

[0107] Figure 22 is an additional schematic perspective view showing the ophthalmic implant 550 and the cannula 508. In the embodiment of Figure 22, it can be seen that the interlocking portions 560 and 562 of the delivery tool 552 and the ophthalmic implant 550, respectively, are inserted into the tip opening 532 defined by the cannula 508. As shown, the ophthalmic implant 550 is advanced in the tip direction D such that (compared to the embodiment shown in the previous figure) more of the ophthalmic implant 550 is positioned inside the Schlemm's canal SC. The corresponding surface 561 of the interlocking portion 560 of the delivery tool 552 is still in contact with the inner wall of the cannula 508, maintaining the delivery tool in an interlocked state with the ophthalmic implant 550.

[0108] Figure 23 is an additional schematic perspective view showing the ophthalmic implant 550 and cannula 508. As shown in Figure 23, the ophthalmic implant 550 and delivery tool 552 are advanced further pteroposteriorly so that the delivery tool surface 561 and a portion of the reduced diameter portion 563 pass through the opening 532, thereby allowing the curved portion 553 of the delivery tool to move toward its curved resting position, thereby causing the delivery tool engagement surface 560 to disengage from the complementary engagement surface 562 on the ophthalmic implant 550.

[0109] In some useful embodiments, the delivery tool may be colored to visually distinguish it from the implant. After detachment from the ophthalmic implant, the cannula 508 and delivery tool 552 can be withdrawn from Schlemm's canal SC, leaving the ophthalmic implant 550 in the fully extended position shown in Figure 23. After delivery of the ophthalmic implant 550 is complete, the delivery tool and cannula can be removed from the eye, leaving at least the tip portion of the ophthalmic implant in Schlemm's canal.

[0110] Figure 24 is a perspective view of Schlemm's canal SC after the cannula (as seen in the previous figure) has been withdrawn, leaving the inlet portion of the ophthalmic implant 550 in the anterior chamber and the remainder of the ophthalmic implant 550 in Schlemm's canal. The presence of the ophthalmic implant 550 in Schlemm's canal can facilitate the flow of aqueous humor from the anterior chamber. This flow may include axial flow along Schlemm's canal, flow from the anterior chamber to Schlemm's canal, and flow away from Schlemm's canal through an outlet communicating with Schlemm's canal. When in place within the eye, the ophthalmic implant 550 supports the trabecular network and Schlemm's canal tissue, improving communication between the anterior chamber and Schlemm's canal (via the trabecular network) and between pockets or compartments along Schlemm's canal.

[0111] In some cases, but not limited to, it may be desirable to deliver an ophthalmic implant into Schlemm's canal in combination with another corrective surgery, such as cataract surgery. When an ophthalmic implant is placed during another surgical procedure, it may be desirable to insert the implant through the same incision used for the other procedure. Figure 25A is a perspective view showing another exemplary delivery system 600 that may be used to advance an ophthalmic implant 650 to a target position in the patient's eye through an incision site made for another procedure, such as cataract surgery. The delivery system 600 may include the ophthalmic implant 650 and a cannula 608 defining a passage sized to slidably receive the ophthalmic implant 650. Embodiments of the delivery system 600 may be similar in shape and function to the delivery system 500. Examples of target positions that may be appropriate in some applications include Schlemm's canal, the trabecular network, the suprachoroidal space, and the intra- and peri-anterior chamber regions. Figure 25B is a magnified detail view further showing the ophthalmic implant 650 and the cannula 608 of the delivery system 600.

[0112] The delivery system 600 in Figure 25A can control the advancement and retraction of the ophthalmic implant 650 within the cannula 608. The ophthalmic implant 650 may be positioned at a target location (e.g., Schlemm's canal) by advancing it through the tip opening 632 of the cannula 608 while the tip opening is in fluid communication with Schlemm's canal. In the embodiment of Figure 25A, the ophthalmic implant 650 is advanced through the tip opening 632 of the cannula 608 for illustrative purposes.

[0113] The delivery system 600 in Figure 25A includes a housing 602, a sleeve 604, and an end cap 610. A tracking wheel 606 extends through the wall of the housing 602 in Figure 25A. The tracking wheel 606 is part of a mechanism that allows the delivery tool 652 of the delivery system 600 to move forward and backward. The delivery tool 652 is slidably positioned within a cannula 608 and is configured to extend through the tip opening of the cannula 608. When the tracking wheel is rotated, the delivery tool 652 moves axially along the passage defined by the cannula 608. The axial direction may be the tip direction D or the proximal direction P. The delivery tool 652 may be similar in shape and function to the delivery tool 152.

[0114] In the embodiment shown in Figure 25A, the housing 602 is configured to be held in one hand while providing axial forward and backward control of the ophthalmic implant via the tracking wheel 606. This feature of the housing 602 results in a favorable ergonomic relationship of the fingers to the hand. This design provides a configuration that allows a user, such as a physician, to use part of their hand to stabilize the device while leaving the middle or index finger free to move independently from the rest of the hand. The middle or index finger can move independently and freely to rotate the wheel to advance and / or retract the ophthalmic implant.

[0115] Figure 25B is a magnified detail view further showing the cannula 608 of the ophthalmic implant 650 and delivery system 600. The cannula 608 includes a generally tubular member 698 having a proximal portion 640, an intermediate portion 645, an apical portion 644, and an apical end 634. The intermediate portion 645 may extend aptocentrically from a first point 643 on the apical side relative to the proximal portion 641 to a second point 647 on the proximal side relative to the apical end 634. The apical portion 644 may extend aptocentrically from the second point 647 to the apical end 634 of the cannula 608 (shown in Figure 28). In the embodiment of Figure 25, both the apical portion 644 and the intermediate portion 645 may be curved. In some examples, the apical portion 644 may have a smaller radius of curvature and therefore a higher curvature than the intermediate portion 645, but this is not required. In some useful embodiments, the tip portion 644 may be sized and configured to be received by the anterior chamber.

[0116] In some cases, but not limited to, it may be desirable to place the ophthalmic implant 650 during another ophthalmic procedure, such as cataract surgery. It is conceivable that the optimal location of the incision for cataract surgery may not be the same as the optimal location of the incision for simply placing an ophthalmic implant, such as implant 650, into Schlemm's canal. Conventional ophthalmic implant delivery system designs may require two separate incisions when the implant is placed in combination with another ophthalmic procedure, in order to allow the cannula to enter Schlemm's canal substantially tangentially. The curved configurations of both ends of the tip portion 644 may be configured to allow the cannula 608 to enter Schlemm's canal substantially tangentially. Furthermore, the curved configuration of the middle portion 645 is envisioned to allow the cannula 608 to enter Schlemm's canal substantially tangentially, while still allowing it to advance through a typical incision associated with and / or optimized for cataract surgery, such as a scleral tunnel incision, but not limited to. This makes it possible to perform two or more eye procedures using a single incision. Performing multiple procedures through a single incision is further anticipated to reduce patient discomfort and recovery time. Figure 25B shows a delivery tool 652 of the delivery system 600 extending through the tip opening 632 of the cannula 608. The delivery tool 652 includes a locking portion 660 configured to form a connection with a complementary locking portion 662 of the ophthalmic implant 650, as will be described in more detail below. In the embodiment of Figure 25, as the tracking wheel is rotated, the delivery tool 652 and the ophthalmic implant 650 move along the path defined by the cannula 608. The cannula 608 is sized and configured so that its tip can advance into Schlemm's canal through the ocular trabecular network. By positioning the cannula 608 in this way, the tip opening 632 is placed in fluid communication with Schlemm's canal. The ophthalmic implant 650 can be positioned in Schlemm's canal by advancing the ophthalmic implant through the tip opening 632 of the cannula 608 while the tip opening is in fluid communication with Schlemm's canal.The tip of the cannula 608 may include a cutting portion configured to cut through tissues such as the trabecular network and the walls of Schlemm's canal, for example, by providing a sharp edge on the tip 634 that is adapted to cut through such tissues.

[0117] Figure 26 is an enlarged perspective view further showing the delivery system 600 and eye 601 shown in the previous figure. Figure 26 shows a cannula 608 of the delivery system 600 extending through the cornea 603 of eye 601. The tip portion of the cannula 608 is positioned inside the anterior chamber defined by the cornea 603 of eye 601. In the embodiment of Figure 26, the cannula 608 is configured such that its tip opening 632 can be in fluid communication with Schlemm's canal. For example, the tip portion 644 and the intermediate portion 645 of the cannula 608 can be sized and configured so that the cannula 608 can advance through an incision 607 made for another visual surgical procedure.

[0118] In the embodiment shown in Figure 26, the ophthalmic implant is positioned within a passage defined by the cannula 608. The delivery system 600 includes a mechanism that allows the ophthalmic implant to be advanced and retracted along the length of the cannula 608. The ophthalmic implant can be positioned within the Schlemm's canal of the eye 601 by advancing the ophthalmic implant through the tip opening of the cannula 608 while the tip opening is in fluid communication with the Schlemm's canal.

[0119] Figure 27 is a perspective view further showing the delivery system 600 shown in the previous figure. In Figure 27, a portion of the housing 602 has been removed for illustrative purposes. The delivery system 600 includes a delivery tool subassembly 670 and a cannula subassembly 680. The delivery tool subassembly 670 includes a rotary rack gear 620 and a delivery tool (not shown). In the embodiment of Figure 27, the delivery tool extends into a passage defined by the cannula 608. In Figure 27, the cannula 608 can be seen extending beyond the sleeve 604. The cannula subassembly 680 includes the cannula 608, a hub 672, and an extension tube (not shown). In the embodiment of Figure 27, the extension tube of the cannula subassembly 680 is located inside the lumen defined by the rotary rack gear 620.

[0120] The delivery system 600 includes a mechanism 617 that controls the movement of the delivery tool subassembly 670. The mechanism 617 includes a number of components located within a housing 602, which include a tracking wheel 606, an idler gear 622, and a rotating rack gear 620. In the embodiment shown in Figure 27, both the tracking wheel 606 and the idler gear 622 are rotatably supported by the housing 602. Teeth on the tracking wheel 606 engage with teeth on the idler gear 622, and teeth on the idler gear 622 engage with teeth on the rotating rack gear 620. When the tracking wheel 606 is rotated counterclockwise (CCW), the idler gear 622 rotates clockwise (CW), causing the rotating rack gear 620 to move toward the tip (D). When the tracking wheel 606 is rotated clockwise (CW), the idler gear 622 rotates counterclockwise (CCW), causing the rotating rack gear 620 to move toward the base (P). In other embodiments, the idler gear 622 may be removed from the device, thereby allowing the counterclockwise movement of the tracking wheel to move the rack gear toward the base end.

[0121] In the embodiment of Figure 27, the sleeve 604 is fixed to the cannula subassembly 680. The sleeve 604 may be rotated by the user to change the orientation of the cannula 608 relative to the housing 602. The sleeve 604 may include gripping features such as grooves, rubber coatings, or other friction surfaces to facilitate this use (as illustrated). In some applications, correct alignment between the cannula and the iris is advantageous to ensure that the core tube and / or ophthalmic implant advances in the correct trajectory relative to Schlemm's canal or other anatomical structure in the eye into which the ophthalmic implant is implanted. The device is configured to maintain the ophthalmic implant in an aligned state within the device during rotation. Selected groups of components are brought together to allow axial movement of the ophthalmic implant while ensuring that they rotate as a single body. In the embodiment of Figure 27, the cannula subassembly 680 and the delivery tool subassembly 670 can rotate relative to the housing 602 in harmony with the sleeve 604.

[0122] In the embodiment shown in Figure 27, the rotary rack gear 620 is configured to rotate with the sleeve 604 while maintaining the ability to move axially in the amphitheater and proximal directions before, during, and after rotation. As the rotary rack gear 620 moves in the amphitheater and / or proximal direction, a corresponding movement of the delivery tool relative to the cannula 608 occurs. If the delivery tool 652 is coupled to the ophthalmic implant 650, this movement is transmitted to the ophthalmic implant 650. The delivery tool subassembly 670 and the cannula subassembly 680 engage with each other in a keyed configuration, as will be described in more detail below. This keyed configuration allows the delivery tool subassembly 670 and the cannula subassembly 680 to maintain a constant rotational orientation relative to each other, while simultaneously allowing the delivery tool subassembly 670 to move parallel to the cannula subassembly 680 in the amphitheater direction D and the proximal direction P.

[0123] In some embodiments, the delivery tool 652 is formed from a shape memory material (e.g., nitinol), and at least a portion of the delivery tool 652 takes on a curved resting shape when no external force is acting on it. The delivery tool 652 can be prompted to take on a straight shape, for example, by inserting the delivery tool 652 through a straight portion of a passage defined by the cannula 608. When the delivery tool 652 is confined within the cannula 608, the interlocking portions can engage with complementary interlocking portions, thereby joining the delivery tool and the ophthalmic implant together and allowing the delivery tool and the ophthalmic implant to move together through the cannula 608, which will be described in more detail below.

[0124] Figures 28, 29, and 30 show more detailed illustrations of the cannula 608. Figure 28 is a side view of the cannula 608 in this detailed description, Figure 29 is a magnified detail view of the cannula 608, and Figure 30 is a magnified perspective view further showing a portion of the tip portion 644 of the cannula 608. The cannula 608 includes a generally tubular member 698 having a central axis 696. Generally, the tubular member 698 includes a proximal end 641, a proximal portion 640, an intermediate portion 645, a tip portion 644, and a tip portion 634. The cannula 608 may extend over a distance D1 between the proximal end 641 and the tip portion 634. The tubular member 698 may have a length along the central axis 696 that is longer than the distance D1 between the proximal end 641 and the tip portion 634. For example, distance D1 may be in the range of 1.50–3.50 inches (3.81–8.89 centimeters), 2.0–3.0 inches (5.08–7.62 centimeters), or approximately 2.50 inches (6.35 centimeters). The cannula 608 may extend to any desired distance D1. The proximal portion 640 may extend over distance D2 from the proximal end 641 to point 643 on the apicial side of the proximal end 641. The proximal portion 640 may be roughly linear such that distance D2 is approximately equal to or equal to the length of the proximal portion 640 measured along the central axis 696. Distance D2 may be in the range of 1.50–2.50 inches (3.81–6.35 centimeters), 1.75–2.25 inches (4.652–5.72 centimeters), or approximately 2.0 inches (5.08 centimeters). The intermediate portion 645 may extend between the first point 643 and the second point 647, which is located proximal to the tip 634 of the cannula 608. The intermediate portion 645 may extend over a distance D3 from points 643 and 647. The distance D3 may be in the range of 0.15 to 0.50 inches (0.38 to 1.27 centimeters), 0.25 to 0.40 inches (0.64 to 1.02 centimeters), or approximately 0.33 inches (0.84 centimeters). The intermediate portion 645 may have a length along the central axis 696 of the tubular member 698 that is longer than the distance D3.The difference in length between the intermediate portion 645 and distance D3 may be determined by the degree of curvature of the intermediate portion 645, as will be discussed in more detail below. The tip portion 644 may extend between the second point 647 and the tip portion 634. The tip portion 644 may extend to a distance D4 from point 647 and tip portion point 634. Distance D4 may be in the range of 0.05 to 0.30 inches (0.13 to 0.76 centimeters), 0.13 to 0.23 inches (0.33 to 0.58 centimeters), or approximately 0.17 inches (0.43 centimeters). The tip portion 644 may have a length along the central axis 696 of the tubular member 698 that is longer than distance D4. The difference in length between the tip portion 644 and distance D4 may be determined by the degree of curvature of the tip portion 644, as will be discussed in more detail below.

[0125] The tip opening surface 642 surrounds the tip opening 632, which extends through the tip portion 634 and through the side wall of the cannula 608. The beveled edge 665 is located at the tip of the tip opening surface 642 and extends from the tip portion 634 to the base end range 667 of the beveled edge 665. The tubular member 698 defines the tip opening 632, the base end opening 636, and the passage 638 extending between the base end opening 636 and the tip opening 632.

[0126] The proximal portion 640 of the cannula 608 is substantially straight, while the intermediate portion 645 and the tip portion 644 of the cannula 608 may be curved. In the embodiment of Figure 28, the tip portion 644 is curved along its entire length, and the intermediate portion 645 is curved along its entire length. The intermediate portion 645 can be defined as having a curve with a first radius R1, measured from the central axis 696, which determines a first radius of curvature. The length of the intermediate portion 645 along the central axis 696 can be determined by the measured value (degrees) of the arc and the radius of the curve using Equation 1 below.

[0127]

number

[0128] Figure 28A is an additional side view of the cannula shown in Figure 25, and shows a cross-sectional view. For example, the cannula 608 includes a generally tubular member 698 having a central axis 696. The generally tubular member 698 includes a proximal end 641, a proximal portion 640, an intermediate portion 645, an anterior portion 644, and an anterior portion 634. Furthermore, for example, the central axis 696 of the proximal portion 640 is tangential to the tangent at a first point 643 of the intermediate portion 645. Furthermore, the tangent at a second point 647 of the intermediate portion 645 is tangential to the tangent at a second point 647 of the anterior portion 644. The tangent at the anterior portion 634 of the anterior portion 644 and the central axis 696 of the proximal portion may have a third radius R3 having an angle in the range of approximately 90° to 165°.

[0129] The method described in this detailed explanation may include the step of advancing the tip 634 of the cannula 608 through the cornea of ​​the human eye so that the tip 634 is positioned within the anterior chamber. The cannula 608 can then be used to enter Schlemm's canal of the eye, for example, by penetrating the wall of Schlemm's canal using the tip 634 of the cannula 608. The oblique edge 665 may be inserted into Schlemm's canal to keep at least a portion of the tip opening 632 of the cannula 608 in communication with Schlemm's canal. For example, the cannula 608 may be advanced until the tip 634 and oblique edge 665 of the cannula 608 are inserted into Schlemm's canal up to the proximal end range 667 of the oblique edge 665. With the passage of the cannula 608 in fluid communication with the lumen of Schlemm's canal, the ophthalmic implant can be advanced into Schlemm's canal from the tip port of the cannula 608.

[0130] In embodiments further shown in Figures 29 and 30, the tip portion 644 of the cannula 608 defines a trough 654. In some embodiments, the trough 654 is configured to receive the entire outer cross-section of the ophthalmic implant as it is advanced within Schlemm's canal. In this case, the trough 654 may have a depth dimension greater than the width of the ophthalmic implant. This cannula configuration advantageously prevents the ophthalmic implant from crossing the layers of the trabecular meshwork as it is advanced within Schlemm's canal. The trough 654 may also be configured to allow the proximal portion of the ophthalmic implant to be released from the delivery tool in a manner similar to that of the trough 554 described above.

[0131] Briefly referring to Figure 25B, although not explicitly shown, during the advancement of the ophthalmic implant 650, the interlocking portion 660 of the delivery tool 652 and the complementary interlocking portion 662 of the ophthalmic implant 650 may engage with each other such that the proximal end of the ophthalmic implant 650 is proximal to the tip of the delivery tool 652. The surface 661 of the delivery tool 652 abuts against the wall of the cannula 608, preventing the interlocking portion 660 of the delivery tool 652 and the complementary interlocking portion 662 of the ophthalmic implant 650 from disengaging from each other. Once connected in this manner, the delivery tool 652 and the ophthalmic implant 650 move together as the delivery tool is advanced and retracted relative to the cannula 608 by the delivery system mechanism. In some embodiments, the ophthalmic implant 650 has a radius of curvature greater than the radius of curvature of the tip portion 644 of the cannula 608. This configuration ensures that when the ophthalmic implant is pushed tipwise by the delivery system 600, the ophthalmic implant advances reliably along the trough 654.

[0132] Once the cannula 608 is positioned in the desired location, the ophthalmic implant 650 may advance pteroposteriorly while the cannula 608 remains stationary. As the ophthalmic implant advances within Schlemm's canal, the elongated opening 632 can provide direct visualization of the ophthalmic implant 650. The configuration that allows direct visualization of the ophthalmic implant has several clinical advantages. During medical procedures, monitoring the advancement of the implant by viewing it through a trabecular meshwork is often difficult. For example, blood perfusion can push blood into Schlemm's canal, preventing the physician from seeing the portion of the implant that has entered the Schlemm's canal. As the ophthalmic implant 650 advances pteroposteriorly along the cannula 608, it advances along the trough 654. The trough opening allows the physician to monitor the advancement of the implant by viewing the implant structure as it advances through the trough before entering Schlemm's canal. The trough opening also allows the physician to locate the position of the pteroposterior portion of the ophthalmic implant relative to the incision made by the cannula to enter Schlemm's canal.

[0133] The delivery tool 652 may advance the ophthalmic implant 650 tipwise until the delivery tool surface 661 and a portion of the reduced diameter portion 663 pass through the opening 632, thereby allowing the curved portion of the delivery tool to move toward its curved resting shape, thereby disengaging the delivery tool engagement surface 660 from the complementary engagement surface 662 on the ophthalmic implant 650. After disengaging from the ophthalmic implant, the cannula 608 and delivery tool 652 can be withdrawn from Schlemm's canal, leaving the ophthalmic implant 650 in a fully extended position. After delivery of the ophthalmic implant 650 is complete, the delivery tool 652 and cannula 608 can be removed from the eye, leaving at least the tip portion of the ophthalmic implant 650 in Schlemm's canal. The inlet portion of the ophthalmic implant 650 may be positioned in the anterior chamber, and the remainder of the ophthalmic implant 650 in Schlemm's canal. The presence of the ophthalmic implant 650 in Schlemm's canal may facilitate the flow of aqueous humor from the anterior chamber. This flow may include axial flow along Schlemm's canal, flow from the anterior chamber into Schlemm's canal, and flow leaving Schlemm's canal through an outlet communicating with Schlemm's canal. When in place within the eye, the ophthalmic implant 650 supports the trabecular network and Schlemm's canal tissue, improving communication between the anterior chamber and Schlemm's canal (via the trabecular network) and between pockets or compartments along Schlemm's canal.

[0134] The cannula 608 may further include a pressure sensor 690 positioned within the trough 654. The pressure sensor 690 may be similar in shape and function to the pressure sensor 180 described above. Although the pressure sensor 690 is shown mounted within the trough 654 of the cannula, it is conceivable that the pressure sensor 690 may be mounted within or at other locations on the cannula 608. The pressure sensor 690 can provide immediate pressure readings during or immediately after implantation of the ophthalmic implant 650. In some examples, pressure readings obtained from the pressure sensor 690 on the cannula 608 can be compared with pressure readings obtained from a pressure sensor mounted on the ophthalmic implant 650, if provided in that manner.

[0135] The pressure sensor 690 may be a micro-electromechanical system (MEMS) pressure sensor. While the pressure sensor 690 is described as a MEMS pressure sensor, it is assumed that other pressure sensors may be used instead of or in addition to the MEMS pressure sensor. Furthermore, although only one pressure sensor 690 is shown, the cannula 608 may contain two or more pressure sensors 690 as needed. MEMS pressure sensors are often formed by anisotropically etching a recess into the back of a die on a silicon substrate, leaving a thin, flexible diaphragm. During use, at least one surface of the diaphragm is exposed to an input pressure (e.g., intraocular pressure). The diaphragm flexes in response to the magnitude of the input pressure, which can be detected by one or more electrical components or sensor elements (e.g., piezoresistives) placed on or embedded in the diaphragm. The change in the resistance of the piezoresistive is reflected as a change in the output voltage signal from the resistance bridge at least partially formed by the piezoresistive. In some examples, the diaphragm can be made thinner by adding support bosses, which may facilitate a higher sensitivity of the diaphragm than that of a flat diaphragm. Circuit elements may be connected so that the sensor element provides some level of signal processing before providing an output signal to the bond pad of the pressure sensor. This signal processing can involve filtering, amplifying, linearizing, calibrating, and / or otherwise processing the raw sensor signal generated by the sensor element (e.g., a piezoristor). Although the sensor element is described as a piezoristor, it is conceivable that the sensor element may be selected to provide a capacitive pressure sensor 690.

[0136] The pressure sensor 690 may further include an antenna or inductor to enable wireless communication of data from the pressure sensor 690 to a reading device. In some examples, if it is desired to transmit data from the pressure sensor 690 to another device located outside the body, the pressure sensor 690 may use radio frequency communication protocols such as cellular communication, ZigBee®, Bluetooth®, Wi-Fi®, IrDA, Dedicated Short Range Communication (DSRC), EnOcean®, or any other suitable radio protocol, but is not limited to these. The data may be transmitted to any number of such appropriately enabled devices, including but not limited to mobile phones, tablet computers, computers, portable handheld devices, such as personal digital assistants (PDAs), or specially designed devices. This may enable physicians, patients, or other parties to monitor intraocular pressure without using a tonometer.

[0137] Components of ophthalmic devices may be made from metals, metal alloys, polymers (some examples thereof are disclosed below), metal-polymer composites, ceramics, combinations thereof and similar materials, or other suitable materials. Some examples of suitable polymers include polytetrafluoroethylene (PTFE), ethylenetetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, e.g., Delrin® available from DuPont), polyether block esters, polyurethane (e.g., Polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyether esters (e.g., Arnitel® available from DSM Engineering Plastics), ether or ester-based copolymers (e.g., ethylene / poly(alkylene ether) phthalate and / or other polyester elastomers such as Hytrel® available from DuPont), polyamides (e.g., Durethhan® available from Bayer or Elf Atchem)Cristamid (registered trademark) available from Atochem, elastomeric polyamides, block polyamides / ethers, polyether block amides (PEBA, available under trade name PEBAX, for example), ethylene vinyl acetate copolymer (EVA), silicone, polyethylene (PE), Marlex high-density polyethylene, Marlex low-density polyethylene, linear low-density polyethylene (for example, REXELL (registered trademark)). (Trademark) Polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalene (PEN), polyether ether ketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly-p-phenylene terephthalamide (e.g., KEVLAR®), polysulfone, nylon, nylon-12 (EMS American Grilon (EMS) The materials may include, for example, Grilamid (registered trademark) available from American Grilon, perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (e.g., SIBS and / or SIBS50A), polycarbonates, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers, polymer / metal composites and the like. In some embodiments, the sheath can be blended with liquid crystal polymer (LCP). For example, the mixture may contain up to about 6% LCP.

[0138] Some examples of suitable metals and metal alloys include stainless steels such as 304V, 304L, and 316LV stainless steel; mild steel; nickel-titanium alloys such as linear elastic and / or superelastic Nitinol; other nickel alloys, e.g., nickel-chromium-molybdenum alloys (e.g., UNS:N06625 such as Inconel® 625, UNS:N06022 such as Hastelloy® C-22, USN:N10276 such as Hastelloy® C276, other Hastelloy® alloys, and similar ones); nickel-copper alloys (e.g., Monel® 400, Nickel VAC (NICKEL UNS:N04400) such as VAC(registered trademark) 400, NICORROS(registered trademark) 400, and similar products, nickel-cobalt-chromium-molybdenum alloys (e.g., UNS:R30035) such as MP35-N(registered trademark) and similar products, nickel-molybdenum alloys (e.g., UNS:N10665) such as Hastelloy(registered trademark) Alloy B2(registered trademark), other nickel-chromium alloys, other nickel-molybdenum alloys, etc. This includes nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and similar materials; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS:R30003, such as ELGILOY®, PHYNOX®, and similar materials); platinum-enriched stainless steel; titanium; combinations thereof; and similar materials; or any other suitable material.

[0139] As suggested herein, within the family of commercially available nickel-titanium or nitinol alloys, there are categories classified as “linear elastic” or “non-hyperelastic” that may be chemically similar to conventional shape-memory and hyperelastic species but exhibit distinct and useful mechanical properties. Linear elastic and / or non-hyperelastic nitinol can be distinguished from hyperelastic nitinol in that it does not exhibit a corresponding “hyperelastic plateau” or “flag region” in its stress / strain curve as hyperelastic nitinol exhibits. Instead, in linear elastic and / or non-hyperelastic nitinol, as the recoverable strain increases, the stress continues to increase in a substantially linear relationship, or a somewhat, but not necessarily perfectly linear relationship, or at least in a relationship that is more linear than the hyperelastic plateau and / or flag region that may be seen in hyperelastic nitinol, until plastic deformation begins. Thus, for the purposes of this disclosure, linear elastic and / or non-hyperelastic nitinol may be referred to as “substantially” linear elastic and / or non-hyperelastic nitinol.

[0140] In some cases, linear elastic and / or non-hyperelastic nitinol can also be distinguished from hyperelastic nitinol in that linear elastic and / or non-hyperelastic nitinol can accept up to approximately 2–5% strain while remaining substantially elastic (e.g., before plastic deformation), while hyperelastic nitinol can accept up to approximately 8% strain before plastic deformation. Both of these materials can be distinguished from other linear elastic materials such as stainless steel (which can also be distinguished based on its composition) which can accept only about 0.2–0.44 percent strain before plastic deformation.

[0141] In some embodiments, linear elastic and / or non-hyperelastic nickel-titanium alloys are alloys that do not exhibit martensite / austenite phase changes detectable by differential scanning calorimetry (DSC) and dynamic metal thermal analysis (DMTA) over a wide temperature range. For example, in some embodiments, there may be no martensite / austenite phase changes detectable by DSC and DMTA analysis in the range of about -60°C to about 120°C in linear elastic and / or non-hyperelastic nickel-titanium alloys. Therefore, the mechanical bending properties of such materials may be largely inert to the effects of temperature over this very wide temperature range. In some embodiments, the mechanical bending properties of linear elastic and / or non-hyperelastic nickel-titanium alloys at ambient or room temperature are substantially the same as their mechanical properties at body temperature, for example, in that they do not exhibit hyperelastic plateaus and / or flag regions. In other words, linear elastic and / or non-hyperelastic nickel-titanium alloys maintain their linear elastic and / or non-hyperelastic characteristics and / or properties over a wide temperature range.

[0142] In some embodiments, the linearly elastic and / or non-superelastic nickel-titanium alloys are in the range of about 50 to about 60 wt% nickel, with the remainder being essentially titanium. In some embodiments, the composition is in the range of about 54 to about 57 wt% nickel. An example of a suitable nickel-titanium alloy is the FHP-NT alloy, commercially available from Furukawa Technomaterials Co., Ltd. (Kanagawa, Japan). Several examples of nickel-titanium alloys are disclosed in U.S. Patent Nos. 5,238,004 and 6,508,803, which are incorporated herein by reference. Other suitable materials may include Ultanium (trademark) (available from Neo-Metrics) and Gum Metal (trademark) (available from Toyota). In some other embodiments, superelastic alloys, such as superelastic nitinol, can be used to achieve the desired properties.

[0143] Numerous features of various embodiments are described above, along with details of the structure and function of various embodiments. However, this detailed description is illustrative only, and it should be understood that modifications in detail are possible, particularly with respect to the structure and arrangement of the parts shown by various embodiments, to the full extent indicated by the broad general meaning of the terms used in the appended claims.

Claims

1. 1. A system comprising: a cannula defining a passageway extending from a proximal end to a distal end, the cannula having a distal opening extending through a sidewall of the cannula and the distal end to form a trough, a curved distal portion, a curved intermediate portion, and a proximal portion, the cannula further including a first pressure sensor disposed within the trough; an ocular implant disposed within the passageway of the cannula; a delivery tool having a distal interlocking portion that engages a complementary interlocking portion of the ocular implant; A system comprising:

2. The system of claim 1 , wherein the first pressure sensor is positioned within the trough opposite the tip opening extending through the side wall.

3. 2. The system of claim 1, wherein the delivery tool is configured to advance the ocular implant through the cannula passage, past the first pressure sensor, and into Schlemm's canal when the tip of the cannula is inserted into Schlemm's canal.

4. The system of claim 1 , wherein the first pressure sensor comprises a micro-electromechanical systems (MEMS) pressure sensor.

5. The system of claim 1 , wherein the first pressure sensor includes an antenna for transmitting data from the first pressure sensor to a remote location.

6. The system of claim 1 , further comprising a second pressure sensor disposed on or within the ocular implant.

7. The system of claim 6 , wherein the second pressure sensor comprises a micro-electromechanical systems (MEMS) pressure sensor.

8. The system of claim 6 , wherein the second pressure sensor includes an antenna for transmitting data from the second pressure sensor to a remote location.

9. The system of claim 1 , wherein the distal interlocking portion of the delivery tool and the complementary interlocking portion of the ocular implant form a mechanical interlocking connection when the interlocking portion of the delivery tool is proximal to the trough of the cannula.

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