Method and apparatus for increasing aqueous humor drainage in the eye

Abstract

To provide a device and a method for destroying eye tissue to treat glaucoma and other conditions.SOLUTION: The distal portion sized and configured for insertion abinterno comprises an elongate flexible shaft, a distal guide member, and a tissue disruptor coupled to the shaft proximal of the guide member. The tissue disruptor comprises a protrusion and a blunt tissue engaging surface without any cutting elements. The distal guide member is configured to be inserted through a trabecular meshwork and into a portion of Schlemm's canal. As the distal guide member is advanced along Schlemm's canal, the tissue engaging surfaces of the projections bluntly dissect the trabecular meshwork tissue and remove a portion of the inner wall of Schlemm's canal.SELECTED DRAWING: Figure 21

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of co-pending U.S. patent application Ser. No. 16 / 719,727, filed December 18, 2019, which is a continuation of U.S. patent application Ser. No. 16 / 699,039, filed November 28, 2019, and claims the benefit of priority under 35 U.S.C. 119(e) to U.S. provisional patent application Ser. No. 62 / 876,799, filed July 22, 2019, the disclosures of which are incorporated herein by reference in their entireties. [Technical Field]

[0002] The present invention is directed to methods and devices for increasing the drainage of aqueous humor in the eye. In one particular application, for example, the devices and methods can be used to remove the trabecular meshwork (with or without a portion of Schlemm's canal) to treat glaucoma and other conditions. [Background technology]

[0003] Current trabecular meshwork resection devices typically use cutting blades or sharp needles (e.g., goniotomy), which have been around for decades. These devices typically create a single, stab-like, partial cut in the trabecular meshwork. More recent devices, such as the Kahook Dual Blade (U.S. Pat. No. 9,872,799), Baersveldt (U.S. Pat. No. 9,999,544), and Trabectome (U.S. Pat. No. 9,820,885) cautery / plasma cutting blades, all have sharp cutting or resection surfaces. Therefore, they all suffer from significant clinical drawbacks related to the nature of the sharp cut during tissue engagement. Sharp blades often result in imprecise, intermittent, and inadequate cutting of the inner canal wall, more akin to tissue maceration, rather than extraction of the desired tissue through non-lacerating, atraumatic removal. This is also often associated with significant bleeding and collateral damage to both the sclera, endothelium, and iris tissue. Furthermore, a single cutting blade can simply open the trabecular meshwork without removing much material. To remove material, some prior art devices provide two spaced apart cutting elements (side by side) in an attempt to remove the material between the cutting elements.

[0004] Prior art ablation devices are also typically limited to straight, rigid intraocular shafts connected to a cutting element in a fixed orientation relative to the shaft. A problem with these devices is the complex motions required to advance the cutting element. The distal end of the shaft must be moved longitudinally and laterally to follow the curved shape, while also changing the angle of the shaft relative to the canal. Even when complex motions are accommodated, another challenging aspect associated with prior art devices with rigid shafts is that the orientation of the cutting element may not follow the contours of Schlemm's canal as desired. Summary of the Invention

[0005] The present invention provides methods and devices for increasing aqueous humor drainage from the eye. Some methods and devices of the present invention remove tissue from the eye to increase aqueous humor drainage. In one aspect, the methods and devices may not utilize a cutting element when ablating the trabecular meshwork. The long-term stability of the incised tissue surface may be significantly less than blunt tissue rhexis, which is characterized by a deeper and sometimes more spontaneous detachment of the meshwork fibril roots from their lateral attachments at their origin. This aspect can be characterized as a "trabeculorhexis," which separates the trabecular meshwork and Schlemm's canal tissue by applying non-cutting shear and tension forces to the tissue to tear and potentially detach the tissue from its attachments. Reducing or eliminating the need for sharp cutting instruments within the eye reduces the potential for incision bleeding, maceration of iris and scleral tissue, and further inadvertent tissue damage to the angle structures of the eye.

[0006] In a further aspect of the invention, the device includes a tissue-engaging portion, which may be an element of a non-cutting blunt probe attached to a shaft. A guide member extends distally from the tissue-engaging portion intended to guide the non-cutting tissue-engaging portion along Schlemm's canal to enable smooth, uninterrupted removal (including transection) of the trabecular meshwork. The shaft may be made of a superelastic material, such that the tissue-engaging portion is capable of tearing a strip of TM along an uninterrupted segment of Schlemm's canal.

[0007] In yet another embodiment, the device includes a flexible shaft that can be extended and retracted from the hand piece. The shaft can be curved or have a curved shape memory / contour, naturally changing the angle of the tissue-engaging portion relative to the hand piece as the shaft extends longitudinally from the hand piece. The shaft can change the angle of the tissue-engaging portion relative to the hand piece by at least 45 degrees as the shaft is extended from the hand piece. The shaft can be flexible and can deform during use to apply a spring load to the tissue-engaging portion. For example, the shaft can be resilient to a force applied in the advancement direction such that the shaft generates a spring load in the advancement direction. The shaft can also be resilient in a direction perpendicular to the advancement direction and in the plane of the curve. Thus, the shaft can generate a spring load during use that has a component in the advancement direction and a component in a radially outward direction relative to the axis of the eye. The shaft is shaped to apply a radially outward force to the tissue relative to the axis of the eye as the tissue-engaging portion moves through the trabecular meshwork, which can help stabilize the device as it advances.

[0008] The device includes an elongate shaft coupled to a handpiece. An actuator is coupled to the elongate shaft for extending and retracting the shaft. A body is coupled to the shaft. The body includes a tissue engagement portion used to disrupt and displace the trabecular meshwork. A guide member extends distally from the body and is positioned and advanced through Schlemm's canal during use. The guide member is sized and configured to be positioned adjacent a wall of Schlemm's canal to guide advancement of the tissue engagement portion in an advancing direction to displace the trabecular meshwork.

[0009] The guide member may be a portion of the shaft that extends beyond the distal end of the body. Stated another way, the elongate shaft may extend distally from the tissue-engaging portion to form at least a portion of the guide member and define the distal end of the guide member. The guide member may extend distally from the body between 300 and 5000 microns and have an upper side and a lower side. The lower surface of the guide member slides against the wall of Schlemm's canal. The upper surface is configured to gather tissue as the tissue-engaging portion moves through the trabecular meshwork during use.

[0010] The upper surface is spaced 250 to 550 microns or 250 to 450 microns from the lower surface, as measured at the center of the upper surface, the center of the upper surface being the farthest portion of the upper surface from the lower surface. The upper surface can have a radius of curvature of 100 to 350 microns, or even 50 to 300 microns. In some embodiments, the upper surface is at least partially defined by the elongate shaft.

[0011] The upper surface may have a radius of curvature that is smaller than the radius of curvature of the lower surface. The upper surface may have a convex surface formed by the elongate shaft. The lower surface may be rounded with a radius of curvature of 400 to 750 microns when viewed along the advancement direction.

[0012] The tissue engaging portion may have a height measured perpendicular to the direction of advancement of at least 150 microns, or may be 500 to 800 microns. The tissue engaging portion may also have a width measured perpendicular to the direction of advancement of at least 450 microns, 450 to 850 microns, or 500 to 700 microns.

[0013] The tissue engaging portion has a tissue engaging surface that has a recess when viewed perpendicular to the advancement direction. The recess has an upper lip and a lower lip, the upper lip forming an angle with the advancement direction when viewed perpendicular to the advancement direction of less than 90 degrees, and may be 30 to 70 degrees. The lower lip forming an angle with the advancement direction when viewed perpendicular to the advancement direction of 0 to 30 degrees. The recess forms an indentation (when viewed in the advancement direction) that has a depth of at least 50 microns, at least 100 microns, or at least 200 microns, and may be 300 to 600 microns.

[0014] The indentation has a indentation height, measured perpendicular to the advancement direction and parallel to the central plane, of at least 200 microns, and may be 300 to 600 microns. The indentation also has a indentation width, measured perpendicular to the advancement direction and parallel to the central plane, that may be 300 to 700 microns, or 400 to 600 microns. In some embodiments, the indentation may be defined in part by a convex portion of the elongate shaft.

[0015] The shaft extends proximally from the body at an angle greater than 90 degrees relative to the direction of advancement, or greater than 135 degrees, and may be at an angle of 160 degrees to 200 degrees relative to the direction of advancement.

[0016] The tissue-engaging portion has first and second side walls extending from the tissue-engaging surface on opposite lateral sides. Leading edges of the first and second side walls can be used to displace tissue with material between the two sides during use, severing the connection with native tissue for removal. Gathering tissue between the first and second side walls and displacing the gathered tissue helps ensure material removal more reliably than simply forming a slit.

[0017] The tissue engaging portion defines a central plane along which the direction of advancement lies. The first and second side walls may form an angle with the central plane of less than 45 degrees or less than 30 degrees. In some embodiments, the tissue engaging portion gathers tissue and displaces it as it advances such that the tissue engaging portion has a blunt engagement with the tissue. The blunt engagement helps ensure that the tissue shears along the first and second side walls due to the displacement of the tissue gathered by the tissue engaging portion.

[0018] The tissue engaging portion can shear tissue without cutting the tissue, such that the tissue engaging portion is a blunt, non-cutting probe. In other embodiments, the tissue engaging portion can include a cutting element without departing from numerous aspects of the present invention. When using blunt engagement, the tissue engaging portion compresses and gathers the tissue to bunch it in a direction perpendicular to the direction of advancement (and generally in the central plane). The tissue engaging portion compresses and gathers the tissue while it tears along the first and second side walls due to movement of the gathered tissue.

[0019] The tissue engaging portion may have a tissue engaging surface (proximal to the guide member) that contacts and moves tissue without cutting it. The tissue engaging surface may be oriented within 15 degrees, or even within 10 degrees, of perpendicular to the direction of advancement to help gather the tissue for movement.

[0020] The tissue-engaging portion and shaft are shaped and configured to allow continuous advancement along Schlemm's canal through an angle of 30 to 120 degrees. The shaft can be made of any suitable material, such as a superelastic material like Nitinol. The shaft can have a curved shape with a radius of curvature of 5.0 to 9.0 mm, and the curved shape can extend over 160 to 270 degrees.

[0021] The tissue engaging surface may have a width of at least 400 microns, or may be in the range of 500 to 800 microns. The tissue engaging surface may have a height of at least 400 microns, at least 500 microns, or in the range of 550 to 1000 microns.

[0022] The elongate shaft may have a cross-sectional shape with a minor axis and a major axis. The major axis may be within 30 degrees, or within 15 degrees, of perpendicular to the central plane. The major axis may be at least 20% larger than the minor axis, and the minor axis may be less than 250 microns, while the major axis is greater than 250 microns.

[0023] The elongated shaft advances essentially longitudinally to advance the tissue-engaging portion through the trabecular meshwork. Furthermore, the curved shape of the shaft allows it to naturally follow the shape of the canal, thereby significantly reducing the amount of manipulation required compared to prior art devices. The tissue-engaging portion is configured for ab interno introduction into the eye. The shaft extends through a cavity within the introducer. The introducer has a curved tip (curved 15 to 60 degrees) to facilitate introduction of the guide member into the canal.

[0024] The shaft is coupled to a handpiece having an actuator. The actuator is coupled to the shaft to extend the shaft from the handpiece. As the shaft extends longitudinally from the handpiece, the curved shape of the shaft naturally changes the angle of the tissue-engaging portion relative to the handpiece. As the shaft extends from the handpiece, the shaft changes the angle of the tissue-engaging portion relative to the handpiece by at least 45 degrees (following the curvature of the tube).

[0025] The shaft may also be flexible, deforming during use to apply a spring load to the tissue-engaging portion. In this manner, the shaft is elastic in the advancing direction, causing the shaft to generate a spring load in the advancing direction. Similarly, the shaft is also elastic in a direction perpendicular to the advancing direction (and in the plane of the curve). The elastic nature of the shaft in this direction generates a light spring load in a radially outward direction relative to the axis of the eye (or the round shape of the canal). Thus, the shaft can generate a spring load that has a component in the advancing direction and a component in the radially outward direction. In this manner, the shaft is shaped to apply a radially outward force to the tissue (specifically the wall of the canal) as the tissue-engaging portion moves through the trabecular meshwork.

[0026] The shaft effectively has variable stiffness by varying the length of the shaft extending from the handpiece. The user can "dial in" the desired stiffness by extending or retracting the shaft and then manipulate the handle to move the tissue-engaging portion at a fixed stiffness and length from the handle. The variable stiffness of the shaft can vary by at least 10 times when moving between the first and second operating positions. The first and second operating positions represent different lengths of the shaft extending from the introducer tube. The shaft can have an advancement and / or radial (orthogonal to the advancement direction) stiffness of less than 20 N / mm. The radial direction is perpendicular to the advancement direction and lies in the plane of the curve. The force exerted by the shaft in this direction (radially outward) tends to press the body against the eye as it moves the tissue-engaging portion to displace tissue.

[0027] The tissue engaging portion has a tissue engaging surface with a height measured perpendicular to the advancement direction that may be at least 300 microns, or may range from 550 to 1200 microns, or even 800 to 1200 microns. The tissue engaging portion and tissue engaging surface also have a width measured perpendicular to the advancement direction and radial direction in use that is at least 300 microns, or may range from 300 to 700 microns.

[0028] The tissue engaging portion can quickly attain a steep angle to gather, compress, and push tissue in an advancing direction. Many prior art devices use relatively long ramps that tend to stretch and lift tissue at the ramp. Such ramps can tend to apply an upward force that can stretch the tissue between the sides, increasing the likelihood that the tissue will separate along a single separation line between the sides, rather than tearing along two sides to remove the tissue as described herein. The device of the present invention can have a relatively small height H when the tissue engaging portion begins to form a relatively steep angle to gather, compress, and subsequently tear tissue along the sides. To this end, the body extends proximally from the guide member and has a height that increases in the proximal direction. When the increasing height reaches 0.014 inches, the tissue engaging portion increases to an angle of 60 degrees relative to the advancing direction within a distance D measured in the advancing direction of 0.035 inches. Alternative ranges are when the height reaches 0.012 inches and the angle reaches 80 degrees within 0.030 inches, or when the height reaches 0.010 inches and the angle reaches 90 degrees within 0.025 inches. Stated differently, the height may be 0.035 or less when the tissue engaging portion 10 is at an 80 degree angle relative to the advancing direction AD, and 0.027 or less when the tissue engaging portion 10 is at a 90 degree angle relative to the advancing direction.

[0029] The width of the tissue engaging portion 10 may be moderate in the area where the tissue is gathered. The width may be 0.010 inches to 0.0030 inches when the tissue engaging portion 10 increases to an 80 degree angle relative to the direction of advancement, and 0.012 inches to 0.0025 inches when the tissue engaging portion 10 increases to a 90 degree angle relative to the direction of advancement.

[0030] The device can further include a suction element coupled to the tissue-engaging portion. The cutting element can be oriented to form a cut that is oriented radially outward relative to a central axis of the eye. The cutting element can be within 60 degrees, or within 30 degrees, or within 15 degrees of the radially outward direction defined by the circular shape of the eye.

[0031] The cutting element, due to the properties of the shaft described herein, can create uninterrupted cuts in the wall of Schlemm's canal of at least 45 degrees, or even at least 90 degrees. Of course, smaller cuts (smaller angular ranges) can be created without departing from the scope of the present invention. The cutting element extends outward from the bottom surface of the tissue-engaging portion, which slides against the canal wall during use. Therefore, the shaft also provides a light spring load in this direction to stabilize the cutting element. The circumferentially oriented cuts in the wall can increase the effective size of Schlemm's canal by increasing the amount of sealing. The cutting element is also positioned so that the circumferential slits form channels that provide fluid communication on the fluid outflow side of the wall of Schlemm's canal formed by the sclera. The circumferential slits also increase the effective surface area available for fluid transport, essentially shortening the circumferentially outward fluid path.

[0032] In use, the device is introduced into the anterior chamber of the eye in any suitable manner, such as by an ab interno approach. In some embodiments, the tissue engagement portion may not include a cutting or resection element, such that the tissue is divided by the trabeculohexil; however, a cutting element may be used in conjunction with or independently of the trabeculohexil. The tissue engagement portion is moved to separate the tissue by the trabeculohexil and may not include a cutting or resection element. The tissue engagement portion displaces the tissue, such that the tissue displaced by the tissue engagement portion tears away from the native tissue due to the displacement. Furthermore, the implantable structure is not coupled to a handpiece or otherwise provided or deployed. Of course, implantable structures may be incorporated without departing from the present invention.

[0033] The aspiration lumen may be coupled to the handpiece for aspirating tissue displaced by the tissue-engaging portion into the aspiration lumen. The introducer tube may form part of the aspiration lumen, and the shaft may be retracted to remove part or all of the aspiration lumen. The device may also include a part-off mechanism for separating the removed tissue strip from native tissue still attached to the eye. The part-off mechanism may be a loop with the tissue strip extending through the loop as the tissue-engaging portion is advanced.

[0034] These and other aspects of the present invention will become apparent from the following description of the preferred embodiments, the drawings and the claims. [Brief explanation of the drawings]

[0035] [Figure 1A] 1 shows a device for removing tissue from an eye having a handpiece with an actuator for manipulating a tissue engaging portion. [Figure 1B] FIG. 1B is a cross-sectional view of the handpiece of FIG. 1A. [Figure 1C] FIG. 1B is a top view of the handpiece of FIG. 1A. [Figure 1D] FIG. 1B is an enlarged view of the distal end of the device of FIG. 1A. [Figure 2A] 10 shows an introducer tube receiving the shaft of the tissue engaging portion. [Figure 2B] FIG. 2B is a perspective view of the introducer tube of FIG. 2A. [Figure 3A] 1 shows the end of the introducer with the tissue engaging portion housed within the cavity of the introducer. [Figure 3B] 13 shows another view of the end of the introducer with the curved shaft extended to advance the tissue engaging portion. FIG. [Figure 3C] 1 shows a close-up view of the distal end of the introducer. [Figure 4] 10 shows a tissue engaging portion attached to a shaft. [Figure 5] 5 shows another view of the tissue engaging portion of FIG. 4. [Figure 6] 1 shows another device for removing tissue from the eye. [Figure 7] FIG. 7 is a side view of the device of FIG. 6. [Figure 8] FIG. 7 is a top view of the device of FIG. 6. [Figure 9] 1 shows another device for removing tissue from the eye. [Figure 10] 10 shows the underside of the guide member of the device of FIG. 9. [Figure 11] FIG. 10 is a side view of the tissue engaging portion of FIG. 9 housed within an introducer. [Figure 12] 10 shows the tissue engaging portion of FIG. 9 with the guide member partially extending from the introducer. [Figure 13] 1 shows another device for removing tissue from the eye. [Figure 14] FIG. 14 is an end view of the device of FIG. 13. [Figure 15A] 10 shows another device having a shaft and tissue engaging portion integrally formed with a shaped wire. [Figure 15B] 15B shows the distal end of the shaft and tissue engaging portion of FIG. 15A. [Figure 15C] 15B shows another view of the distal end of the shaft and tissue engaging portion of FIG. 15A. [Figure 16] 1 shows another device for removing tissue from the eye. [Figure 17] 17 shows the distal end of the device of FIG. 16. [Figure 18] A cross-sectional view of the distal end is shown. [Figure 19] 1 shows the distal end of the shaft advanced from the introducer. [Figure 20] FIG. 10 is another view of the distal end. [Figure 21] 10 shows another device for removing tissue from an eye that includes a cutting element. [Figure 22A] The entrance and exit openings formed in the trabecular meshwork are shown. [Figure 22B] The entrance and exit openings formed in the trabecular meshwork are shown. [Figure 23]The device is shown introduced into the entrance opening and advanced towards the distal opening. [Figure 24] 1 shows an apparatus including a part-off mechanism. [Figure 25] 10 shows a diagram of the device in relation to the dimensions of the tissue engaging portion. DETAILED DESCRIPTION OF THE INVENTION

[0036] Referring to Figures 1 through 5, a device 2 for disrupting the inner wall of a canal is shown. In one embodiment, the device 2 disrupts the canal wall with a blunt trabeculohexil. The trabeculohexil bluntly engages the tissue, tearing and / or shearing, or can achieve severance of the trabecular meshwork from its attachment to the sclera and surrounding angle anatomy without cutting. The device 2 has a tissue engagement portion 10 attached to a shaft 6. The tissue engagement portion 10 is a non-cutting, elongated, blunt probe that moves through the canal and engages the trabecular meshwork as it slides along the inner wall (or outer wall) of Schlemm's canal. The device 2 includes a body 12 having the tissue engagement portion 10, which may be a blunt tissue disruptor that spans the trabecular meshwork to form a continuous, non-cutting trabeculohexil. The device 2 stretches and tears the trabecular meshwork fibers to follow the contours of Schlemm's canal, transecting a portion of the tissue at its origin.

[0037] Referring to Figures 4 and 5, the device 2 has a guide member 15 extending from a body 12, which serves as a leading end for engaging the tube of a blunt, non-dissecting probe. The body 12 has a first sidewall 14 on one side and a second sidewall 16 on the opposite side. The tissue engagement member 10 is introduced into the anterior chamber of the eye, with the guide member 15 positioned adjacent to the wall of Schlemm's canal (which may be the outer wall, leaving the Schlemm's canal intact, or the inner wall, if the guide member 15 is positioned inside the Schlemm's canal to remove a portion of the Schlemm's canal). The tissue engagement member 10 is then moved by manipulating the shaft to advance the guide member in an advancing direction AD along the wall of the Schlemm's canal and remove a portion of the trabecular meshwork. The tissue engagement member 10 may be a blunt, non-dissecting probe configured to engage the trabecular meshwork tissue ab-interno and bluntly tear or transect the trabecular meshwork tissue. During use, tissue engaging portion 10 can strip the inner wall of Schlemm's canal as guide member 15 advances through the canal. Guide member 15 extends distally from body 12 a distance of 300 to 5000 microns, although guide member 15 may be shorter or longer without departing from many aspects of the present invention.

[0038] The shaft 6 may have a curved portion 11 extending proximally from the body 12 (from the tissue-engaging portion 10) and forming a semicircle (or capable of assuming a memorized curved shape / contour) with a contour similar to the structure of the limbus of the eye, approximating a circle with a diameter of approximately 12 mm. The diameter of the arc span of the flexible shaft 6 may have a memorized shape slightly exceeding the diameter of the limbus of an average eye, which enables a slight radial outward force due to the shape of the shaft 6 as it moves along the canal, thereby allowing the stronger outer scleral wall to further guide the device and minimizing pressure on the weaker inner trabecular meshwork wall. The curved portion 11 may extend over an angle of more than 135 degrees, may be 160 to 200 degrees, and may have a radius of curvature of 5.0 to 9.0 mm. The central plane CP is defined as the plane in which the advancement direction AD lies and which contains the shaft 6 at its junction with the tissue-engaging portion 10. The central plane CP may also be defined as the plane in which the advancement direction AD lies and which lies on the centerline of the tissue engagement portion 10 when viewed along the advancement direction AD. The central plane CP may also be defined simply as the plane containing the circular shape of Schlemm's canal. The shaft 6 may be made of a flexible, shape-memory material as needed to substantially conform to the contours of the eye. The curved portion 11 also defines a curved plane PC in use. The shaft 6 has a curved shape that lies in the curved plane PC in use, which is aligned with the plane in which the circular Schlemm's canal lies.

[0039] 1-3, device 2 includes handpiece 13 with shaft 6 coupled to handpiece 13 and operated by actuator 25, which translates shaft 6 back and forth to retract shaft 6 from handpiece 13. When shaft 6 extends from handpiece 13 in use, curved portion 11 of shaft 6 naturally changes the angle of tissue engaging portion 10 relative to the handpiece (and the orientation of the longitudinal axis of shaft 6 at its distal end) by at least 45 degrees, and may even be up to 180 degrees. As shaft 6 extends longitudinally from the handpiece, the curved portion of the shaft naturally changes the angle of tissue engaging portion 10 relative to the handpiece.

[0040] The handpiece 13 may also include an introducer 17 (FIGS. 2A and 2B), with the elongated shaft 6 extending through a cavity 19 of the introducer 17. The curved portion 11 of the shaft 6 is in a straight, biased state when received within the cavity 19 of the introducer 17. The introducer 17 may have a curved tip 21 at its distal end 23, which is curved 15 to 60 degrees to facilitate insertion of the device 2 into the trabecular meshwork and to guide the tissue engagement portion 10 in a desired direction along Schlemm's canal. The distal end 27 of the cavity 19 is inserted into the trabecular meshwork while the tissue engagement portion 10 is received within the cavity 19. The curved tip 21 of the introducer 17 is curved 15 to 60 degrees to facilitate smooth entry into (or into the outer wall of) Schlemm's canal. The cavity 19 may also be coupled to a suction source 29 so that tissue can be removed from the eye by the device 2. Alternatively, a separate suction device may be used to remove the tissue.

[0041] Referring to FIG. 3B , the elongate shaft 6 may be flexible and resilient to provide a “soft” feel during use, with the shaft 6 elastically deflecting during use. Specifically, the shaft 6 may be resilient to forces exerted on the tissue-engaging portion 10 in the advancement direction AD. The shaft 6 may be made of a metal or a superelastic material, such as nitinol, which provides a wide range of elastic response. For example, the shaft may be a 0.15 mm diameter nitinol wire, which may be 0.10 to 0.25 mm. In this manner, the shaft 6 generates a slight spring load in the advancement direction AD as it advances. The curved portion 11 of the shaft 6 also provides an elastic response in a direction perpendicular to the advancement direction AD and in the plane of curvature PC. Thus, the shaft 6 can generate a spring load having a component C1 in the advancement direction and a component C2 in a radially outward direction relative to the axis of the eye. In this manner, the radially outward force causes the tissue-engaging portion 10 to slide against the sclera (or the outer wall of Schlemm's canal) to stabilize the tissue-engaging portion 10. Stated another way, as the tissue-engaging portion 10 moves through the trabecular meshwork tissue, the curved shaft 6 is shaped to apply a radially outward force to the tissue relative to the axis of the eye. The resilience of the shaft 6 also prevents excessive force from being inadvertently applied to the eye. The flexible, spring-loaded characteristics of the shaft can also limit or prevent the accidental application of excessive force or movement. The curved portion 11 of the shaft 6 may extend over an angle of more than 180 degrees, and may be 240 degrees or greater. The curved portion 11 may have a radius of curvature of approximately 7.5 mm.

[0042] As used herein, when referring to the stiffness, elasticity, or spring constant of the shaft 6, the shaft 6 must be (positioned, or otherwise configured) to be operable when moving the tissue-engaging portion to displace the tissue to be removed. The shaft 6 can have a stiffness in the advancement direction of less than 20 N / mm, less than 10 N / mm, or even less than 5 N / mm when the tissue-engaging portion is moved to displace the tissue. The shaft 6 can also have a stiffness in a direction perpendicular to the advancement direction and in a curved plane of less than 20 N / mm, less than 10 N / mm, or even less than 5 N / mm, which presses the main body against the eye when the tissue-engaging portion is moved to displace the tissue. When the guide member is positioned in Schlemm's canal, a perpendicular force presses the main body (and guide member) against the sclera. While the shaft 6 can have the desired stiffness characteristics, the shaft 6 can also change the angle of the tissue-engaging portion 10 by at least 45 degrees, and may also be able to change the angle by at least 90 degrees (by extending or retracting the shaft). The angle of the shaft 6 is changed simply by extending it from the introducer 19. The shaft 6 extends from the tissue-engaging portion 10 at an angle A greater than 90 degrees, or even greater than 135 degrees, relative to the direction of advancement AD, and may be between 160 and 200 degrees, or even between 160 and 240 degrees. An advantage of the shaft 6 is that the complex movement of the handpiece is reduced compared to devices with rigid shafts that require the shaft angle to be changed as the device advances through the canal. Non-flexible (rigid) shafts are limited to partial angulation (only between 10 and 120 degrees) at the ab-interno entry site into the anterior chamber. Alternatively, the flexible shafts of the present invention may be made of elastic or superelastic alloys or polymers that provide sufficient flexibility to access the entire inner circumference of the anterior chamber and the anatomical structures of the angle. Given the limited degrees of freedom and movement of devices introduced into the eye, such movement with a rigid shaft can be difficult. The present invention can reduce or even eliminate the need to change the angle of the shaft / handpiece when breaking a tube.Although the present invention describes trabec- lohexylation rather than cutting, many aspects of the present invention may be practiced with cutting elements rather than tissue-ripping / stripping / tearing elements. For example, all aspects of shaft 6 may be practiced with tissue-engaging portion 6 cutting tissue.

[0043] The shaft 6 can also have variable stiffness by simply changing the length of the shaft 6 extending from the handpiece 13, providing clear advantages when encountering different tissue conditions and approach angles. The variable stiffness of the shaft 6 may vary by at least 10 times when moving between a first and a second operating position, such that the first position, which has the least stiffness, is at least 10 times less than the second position, which has the greater stiffness, and both positions are operable to move tissue. The variable stiffness can be achieved by simply retracting and extending the shaft 6 to change the length of the shaft 6 extending from the handpiece (specifically the introducer), and the first and second operating positions may change the orientation of the distal end of the shaft by at least 45 degrees relative to the handpiece 13. The cross-section of the shaft 6 may be constant or may increase proximally to maintain more consistent stiffness. For example, the stiffness of the curved portion that is extended or retracted to change the angle of the shaft 6 by at least 45 degrees may change by less than 30%.

[0044] Guide member 15 has an upper surface 18 and a lower surface 20, with lower surface 20 positioned adjacent the wall of Schlemm's canal so that guide member 15 slides against the sclera or outer wall of Schlemm's canal. Tissue-engaging portion 10 has a height H, measured perpendicular to the direction of advancement AD from upper surface 18 to lower surface 20 (and across the wall of Schlemm's canal in a direction essentially radially inward relative to the circularity of the channel), of at least 150 microns, and may be 500 to 1200 microns, or even 500 to 800 microns, although any suitable height can be used depending on the desired amount of trabecular meshwork to be removed. Tissue-engaging portion 10 has a width W, measured perpendicular to the direction of advancement (and height H), of at least 300 microns or at least 400 microns, and may be 300 to 700 microns, or 450 to 850 microns, or even 500 to 700 microns.

[0045] The height H and width W of the tissue-engaging portion are intended to capture and gather the trabecular meshwork. In this manner, the gathered tissue is less likely to tear or rip between the first and second sidewalls 14, 16 compared to tissue along the first and second sidewalls 14, 16. The lower surface 20 slides against the wall of Schlemm's canal or the sclera. The tissue may be gathered by the upper surface 18, which may be spaced 250 to 700 microns or 400 to 700 microns from the lower surface 20, with alternative ranges being 250 to 550 microns, and the center of the upper surface 18 may be 250 to 450 microns, which may be the farthest portion of the upper surface 18 from the lower surface 20.

[0046] The tissue engaging portion 10 has a tissue engaging surface 31 that can have a recess 33 when viewed perpendicular to the advancement direction. The recess 33 has an upper lip 35 and a lower lip 37 that can help gather and compress tissue together as the device 2 advances. The upper lip 35, when viewed perpendicular to the advancement direction AD, forms an angle A2 with the advancement direction AD that is less than 90 degrees (and may be 30 to 70 degrees), and the lower lip 37, when viewed perpendicular to the advancement direction AD, can form an angle A3 with the advancement direction AD that is 0 to 30 degrees. The recess 33 forms an indentation 39 when viewed perpendicular to the advancement direction AD. The indentation 39 has a depth of at least 50 microns measured perpendicular to a line extending between the upper lip 35 and the lower lip 37 of the indentation 39. Stated another way, the indentations 39 have an indentation depth 41 measured in the advancing direction of at least 100 microns, at least 200 microns, or even 300 to 600 microns. The indentations 39 have an indentation height 43 measured perpendicular to the advancing direction AD and parallel to the central plane CP that is at least 200 microns, and may be 300 to 600 microns. The indentations 39 can also have an indentation width 45 measured in the advancing direction AD and perpendicular to the central plane CP that is 300 to 700 microns, and may be 400 to 600 microns.

[0047] The first and second sidewalls 14, 16 extend from the tissue-engaging surface 20 on opposite sides thereof. The first and second sidewalls 14, 16 can have a height of at least 150 microns and can be 500 to 800 microns (measured perpendicular to the advancing direction AD) and 200 to 500 microns in length (measured along the advancing direction AD). The first and second sidewalls 14, 16 can form an angle with the central plane CP of less than 45 degrees, and even less than 20 degrees. The first and second sidewalls extend from the tissue-engaging surface 31 on opposite sides thereof.

[0048] The tissue engaging portion 10 can gather tissue and move it by engaging it without blunt tearing. As the tissue engaging portion 10 moves the gathered tissue forward, the tissue along the first and second side walls 14, 16 is sheared and / or torn without the need for a cutting or cutting element. In other words, the tissue engaging portion 10 compresses and gathers the tissue, bunching it between the upper lip 35 and the lower lip 37 in a direction perpendicular to the forward direction AD and in the central plane CP. The tissue engaging portion 10 compresses and gathers the tissue while it is torn and sheared along the first and second side walls 14, 16 during movement of the gathered tissue. The tissue engaging portion 10 can move continuously through the trabecular meshwork along any angular range of Schlemm's canal, such as 10 to 360 degrees or 30 to 120 degrees. The tissue engaging portion 10 shears tissue along the first sidewall 14 and the second sidewall 16 due to the movement of the tissue gathered by the tissue engaging portion 10. Stated another way, the tissue engaging portion 10 compresses and gathers the tissue to bunch it in a direction perpendicular to the advancement direction and in a central plane. Stated yet another way, the tissue engaging portion 10 compresses and gathers the tissue while tearing the tissue along the first sidewall 14 and the second sidewall 16 due to the movement of the tissue gathered by the tissue engaging portion 10. The tissue engaging portion 10 may also lack a piercing element and tear tissue without cutting or resecting, although many embodiments may be implemented with the tissue engaging portion 10 cutting tissue as described above. The tissue engaging portion 10 is a blunt, non-dissecting probe that can displace the trabecular meshwork tissue to bluntly transect the trabecular meshwork tissue.

[0049] The tissue engaging portion 10 can strip the inner wall of Schlemm's canal as the guide member 15 advances through the canal, or leave the canal intact as the guide member 15 slides along the outer wall of the canal. The tissue engaging portion 10 has a tissue engaging surface 20 proximal to the guide member 15. The tissue engaging surface 20 can contact and move tissue without cutting it. The tissue engaging surface 20 has an orientation that is within 15 degrees, and may be within 10 degrees, of perpendicular to the direction of advancement AD. The tissue engaging surface 20 can have a width W of at least 400 microns, or may be 500 to 800 microns. The tissue engaging surface can have a height H of at least 300 microns, at least 400 microns, at least 500 microns, or may be 550 to 1200 microns, or even 800 to 1200 microns. The width W of the tissue engaging surface helps gather tissue in front of the tissue engaging surface. In this manner, the tissue is torn / torn / sheared away from the native tissue due to the movement of the tissue gathered in front of the tissue engaging surface. This movement of the tissue promotes bilateral tearing of the tissue, thereby releasing a strip of the trabecular meshwork. Thus, stated another way, the tissue engaging surface may displace tissue having a width of at least 300 microns, and may be at least 400 microns.

[0050] Referring to Figures 6 through 8, another device 2A for removing tissue from the eye is shown, where identical or similar reference numerals refer to identical or similar structures. The device 2A has a tissue-engaging portion 10A attached to a shaft 6A. The shaft 6A can have any of the characteristics of the shaft 6 described herein, and the shaft 6A is attached to a handpiece 13 (Figure 1A) in the same manner and use as the shaft 6, and all such uses, features, and characteristics are incorporated herein. The device 2A also has a non-cutting, non-ablating tissue-engaging portion 10A that engages and moves the trabecular meshwork. The tissue-engaging portion 10A (formed by the body 12A) gathers the tissue, stretching and tearing the tissue (trabecular meshwork) along the first sidewall 14A and the second sidewall 16A so that the tissue follows the contours of Schlemm's canal. The shaft 6A may also be made of any suitable material, including metal, including superelastic materials such as Nitinol.

[0051] The device 2A has a guide member 15A that guides the device 2A along Schlemm's canal. The body 12A has a first sidewall 14A and a second sidewall 16A on opposite lateral sides of the body 12A. The guide member 15A may extend distally from the body 12A by a distance of 30 to 500 microns, although the guide member 16A may be shorter or longer without departing from many aspects of the present invention. The shaft 6A extends proximally from the tissue-engaging element 10A. The central plane CP2 is defined as the plane in which the advancement direction AD lies and includes the shaft 6A at its connection to the body 12A (tissue-engaging portion 10A). The central plane CP2 may also be defined as the plane in which the advancement direction AD lies and the curved portion 11 of the shaft 6A. The central plane CP2 also defines the plane in which Schlemm's canal lies.

[0052] The guide member 15A has an upper surface 18A and a lower surface 20A, and in use, the lower surface 20A slides against the wall of Schlemm's canal. The tissue engaging portion 10A has a height H2 measured perpendicular to the advancement direction AD2 of less than 600 microns, which may be 50 to 500 microns. The tissue engaging portion 10A also has a width W2 (measured perpendicular to the advancement direction) which may be 50 to 500 microns. The tissue engaging portion 10A may also have a tissue engaging surface 20A having a recess 22A when viewed perpendicular to the advancement direction AD2. The recess 22A has an upper lip 24A and a lower lip 26A that help gather and compress tissue as the device 2A is advanced. The upper lip 24A may form an angle A3 with the advancement direction AD of less than 90 degrees, or alternatively, an angle of 30 to 70 degrees, when viewed perpendicular to the advancement direction AD. The recess 22A may form a depression 28A (when viewed perpendicular to the direction of advancement) that has a depth of at least 50 microns measured perpendicular to a line extending between the upper and lower lips.

[0053] The first and second sidewalls 14A, 16A extend from the tissue engaging surface 20A on either side of the tissue engaging surface 20A. The first and second sidewalls 14A, 16A can have a height (measured perpendicular to the advancement direction AD) of 500 to 800 microns and a length (measured along the advancement direction AD) of 180 to 220 microns.

[0054] 9-12, another device 2B for removing tissue from the eye is shown, in which identical or similar reference numerals refer to identical or similar structures. Device 2B has a tissue-engaging portion 10B attached to an elongate shaft 6B to form a non-cutting, blunt tissue-engaging portion 10B. Tissue-engaging portion 10B (formed by body 12B) stretches and tears trabecular meshwork fibers as described herein. Shaft 6B may also be constructed of a metal, such as a superelastic material (Nitinol).

[0055] The device 2B has a guide member 15B that guides the device 2B along Schlemm's canal. The guide member 15B may be formed from a formed sheet metal. The body 12B has a first sidewall 14B and a second sidewall 16B on corresponding sides of the body 12B. The guide member 15B may extend distally from the body 12B by a distance of 30 to 500 microns. The central plane CP3 is defined as the plane in which the advancement direction AD lies and which includes the shaft 6B at the junction of the shaft 6B and the tissue engaging portion 10B. The central plane CP3 may also be defined as the plane in which the advancement direction AD lies and which is located on the centerline of the tissue engaging portion 10B when viewed along the advancement direction AD. The shaft 6B may be made of a flexible, shape-memory material, as needed, to conform to the contours of the eye.

[0056] Guide member 15B has an upper surface 18B and a lower surface 20B, with lower surface 20B sliding against the wall of Schlemm's canal in use. Lower surface 20B may be laser etched, chemically etched, or ground to provide a desired texture. Tissue engaging portion 10B has a height H3 measured perpendicular to the direction of advancement AD and a width W3 (measured perpendicular to the direction of advancement) that may have a range of dimensions relative to any of the other devices described herein, all of which dimensions are incorporated herein.

[0057] Additionally, tissue engaging portion 10B may have a tissue engaging surface 20B having a recess 22B when viewed perpendicular to the advancement direction AD. Recess 22B has an upper lip 24B and a lower lip 26B that serve to gather and compress tissue as device 2B advances. The gathered tissue is displaced, and the gathered / displaced tissue tears / shears / tears the tissue from the native tissue. Upper lip 24B may form an angle of less than 90 degrees, or an angle of 30 to 70 degrees, with respect to advancement direction AD when viewed perpendicular to advancement direction AD. Recess 22B may form an indentation 28B (when viewed perpendicular to the advancement direction), with indentation 28B having a depth of at least 50 microns measured perpendicular to a line extending between upper lip 24B and lower lip 26B. Indentation 28B may be defined in part by elongate shaft 6B, but may, of course, be formed independently of shaft 6B.

[0058] First and second side walls 14B, 16B extend from tissue-engaging surface 20B on either side of tissue-engaging surface 20B. First and second side walls 14B, 16B can have any of the heights, widths, orientations, and size ranges of the other embodiments described herein that are incorporated herein.

[0059] 13 and 14, yet another device 2C for removing tissue from an eye is shown, in which same or similar reference numbers refer to same or similar structure. Device 2BC has a tissue engaging portion 10C attached to an elongated shaft 6C to form a non-cutting, elongated, blunt probe.

[0060] The tissue-engaging portion 10C (formed by the body 12C) stretches and tears the trabecular meshwork fibers as described herein. The shaft 6C may be Nitinol wire or any other suitable material. The tissue-engaging portion 10C may be a plastic extrusion bond bonded to or formed with the shaft 6C. The body 12C has a first sidewall 14C and a second sidewall 16C on opposite lateral sides of the body 12C, causing the trabecular meshwork to tear. Thus, the collected tissue displaced by the tissue-engaging portion 10C is substantially free from native tissue. The tissue-engaging portion 10C may have a height measured perpendicular to the direction of advancement of at least 150 microns (and may be 500 to 800 microns). The tissue-engaging portion 10C has a width W measured perpendicular to the direction of advancement of at least 400 microns, and may be 450 to 850 microns, or even 500 to 700 microns.

[0061] The elongated shaft 6C extends beyond the distal end of the body 12C to form the guide member 15C. Stated another way, the elongated shaft 6C extends distally from the tissue engagement portion 10C to form at least a portion of the guide member 15C, such that the elongated shaft 6C defines the distal end of the guide member 15C. The guide member 15C is formed by the shaft 6C and may extend distally from the body 12C by a distance of 30 to 500 microns. The guide member 15C has an upper surface 18C and a lower surface 20C, and in use, the lower surface 20C slides against the wall of Schlemm's canal. The upper surface 18C of the guide member 15C may have a convex surface with a radius of curvature of 100 to 350 microns, or even 200 to 300 microns, and may be at least partially (or completely) defined by the elongated shaft 6C. The upper surface 18C may have a radius of curvature that is smaller than the radius of curvature of the lower surface 20C. The lower surface 20C may be rounded with a radius of curvature of 400 to 750 microns when viewed along the advancement direction.

[0062] Elongated shaft 6C may also have a non-circular cross-sectional shape having a minor axis 51 and a major axis 53. The major axis may be within 30 degrees, and may be within 15 degrees, of perpendicular to the central plane. The major axis may be at least 20% longer than the minor axis. The minor axis may be less than 250 microns, while the major axis may be greater than 250 microns. Shaft 6C may be interchangeable with any of the other shafts described herein, and vice versa, and all such features, such as the non-circular cross-section of shaft 6C, may be used with any of the other shafts described herein, including all aspects of shaft 6, such as the generated spring load.

[0063] The first and second sidewalls 14C, 16C extend from the tissue-engaging surface 20C on either side of the tissue-engaging surface 20C. The first and second sidewalls 14C, 16B can have a height (measured perpendicular to the advancement direction AD4) of 500 to 800 microns and a length (measured along the advancement direction AD) of less than 100 microns. The first and second sidewalls 14C, 16C can form an angle with the central plane CP4 of less than 45 degrees, or even less than 20 degrees. The central plane CP4 is defined as the plane in which the advancement direction AD4 lies and which includes the shaft 6C at its junction with the tissue-engaging portion 10C. The central plane CP4 can also be defined as the plane in which the advancement direction AD3 lies and which lies on the centerline of the tissue-engaging portion 10C when viewed along the advancement direction AD3. Another definition is the plane in which the tissue-engaging portion 10C moves, which, of course, essentially corresponds to the shape (circular or a segment thereof) of Schlemm's canal.

[0064] 15A-15C, another device 2D for removing tissue from an eye is shown, in which identical or similar reference numerals refer to identical or similar structure. Device 2D has a tissue engaging portion 10D attached to an elongated shaft 6D to form a non-cutting, elongated blunt probe 8D or tissue engaging portion 10D. Tissue engaging portion 10D is formed by a body 12D attached to shaft 6D.

[0065] The shaft may be integrally formed with the guide member 15D and the tissue-engaging portion 10D. When the guide is integrally formed with the shaft 6D, the distal end of the guide member 15D is simply the distal end of the elongate shaft 6D. The wire 15 forming the shaft 6D may have a bent portion 40 that forms the tissue-engaging portion 10D. The shaft 6D has a curved portion 11D, with the bent portion 40 extending inwardly a distance 55 of 200 to 800 microns relative to the curved portion 11D. The bent portion 40 may form an angle of 10 to 150 degrees with the elongate shaft 6D.

[0066] The elongate shaft 6D may be integrally formed with the tissue engaging portion 10D and guide member 15D. The elongate shaft 6D (and optionally the tissue engaging portion 10D and guide member 15D) may be a wire 15D having an effective radius of 40 to 400 microns, or 50 to 300 microns, although different sizes and shapes may be used without departing from the invention. The shaft 6D may be constructed of a metal such as a superelastic material (Nitinol). The effective radius is the equivalent radius of a circle having the same cross-sectional area for a non-circular cross-section (e.g., elliptical or rectangular).

[0067] The body 12D has a first sidewall 14D and a second sidewall 16D on corresponding sides of the body 12D. The guide member 15D may extend distally from the body 12D a distance of 30 to 500 microns. The shaft 6D extends proximally from the tissue engaging element 10D and may form an angle A4 with the advancing direction AD of greater than 135 degrees, and may be between 160 and 200 degrees. The central plane CP4 is defined as the plane in which the advancing direction AD lies and which includes the shaft 6D at its junction with the tissue engaging portion 10D. The central plane CP4 may also be defined as the plane in which the advancing direction AD lies and which lies on the centerline of the tissue engaging portion 10D when viewed along the advancing direction AD.

[0068] Guide member 15D has an upper surface 18D and a lower surface 20D, and in use, lower surface 20D slides against the wall of Schlemm's canal. Tissue engaging portion 10D has a height H measured perpendicular to the direction of advancement AD and a width W that may be defined by any of the ranges described herein, all of which ranges are expressly incorporated herein. First side wall 14D and second side wall 16D can have heights and lengths within any of the ranges described herein, all of which ranges and embodiments are expressly incorporated herein.

[0069] Referring to Figures 16 through 20, another device 2E for increasing aqueous humor drainage of the eye is shown, where identical or similar reference numerals refer to identical or similar structures. The device 2E has a tissue-engaging portion 10E attached to a shaft 6E. The shaft 6E can have any of the shaft characteristics described herein, and the shaft 6E is attached to a handpiece 13 (see Figure 1A) in the same manner and use as the shaft 6E, and all such uses, features, and characteristics are incorporated herein. The tissue-engaging portion 10E engages and displaces the trabecular meshwork and is part of the body 12E. Tissue is gathered along the first sidewall 14E and the second sidewall 16E, stretching and tearing the tissue as described herein. The shaft 6E may be made of any suitable material, including metal, including a superelastic material such as Nitinol. The tissue-engaging portion 10E is coupled to an introducer 17E, which may be a 0.022-inch stainless steel tube with an end shaped to match the tissue-engaging portion 10E. The introducer 17E includes a 0.014 inch OD sleeve 71E.

[0070] The device 2E has a guide member 15E that guides the device 2E along Schlemm's canal. The guide member 15E may be formed by the shaft 6E as shown, or may be part of the body 12E. The body 12E has a first sidewall 14E and a second sidewall 16E on opposite lateral sides of the body 12E. The guide member 15E may extend distally from the body 12E a distance of 30 to 500 microns, although the guide member 16E may be shorter or longer without departing from many aspects of the present invention. The shaft 6E extends proximally from the tissue-engaging portion 10E. The central plane CP2 is defined as the plane in which the advancement direction AD lies and includes the shaft 6E at its connection to the body 12E (tissue-engaging portion 10E). The central plane CP2 may also be defined as the plane in which the advancement direction AD lies and the curved portion 11 of the shaft 6E. The central plane CP2 also defines the plane in which Schlemm's canal lies.

[0071] The guide member 15F has an upper surface 18E and a lower surface 20E, and in use, the lower surface 20E slides against the wall of Schlemm's canal. The tissue-engaging portion 10E is the portion of the body 12E that displaces tissue and includes a frustoconical surface 49E that tapers to the guide member 15F (which may be an extension of the shaft 6E) and to a substantially tubular portion 51E of the body 12E that forms part of the tissue-engaging portion 10E. The tissue-engaging portion 10E has a height H2 measured perpendicular to the advancement direction AD2, which may be at least 600 microns or may be approximately 1000 microns. The height H2 may be at least 300 microns, at least 400 microns, at least 500 microns, or may be 550 to 1200 microns, or even 800 to 1200 microns. The tissue-engaging portion 10E also has a width W2 (measured perpendicular to the advancement direction), which may be approximately 560 microns. The width W2 is measured perpendicular to the advance direction and may be at least 300 microns, at least 400 microns, or in the range of 300 to 700 microns, 450 to 850 microns, or even 500 to 700 microns.

[0072] The various surfaces and dimensions described herein for all embodiments are intended to be defined by the drawings that relate to a particular surface or orientation. When considering a rectangular cross-section, each of the four defined sides can be fully defined. When a circular cross-sectional shape is used, such as in device 6E, defining the upper and lower surfaces is understood to be a subdivision of the circular cross-section into two semicircles. Similarly, the sidewalls are subdivided into two semicircles, meaning that each portion of the surface can define two surfaces, since the surface is exposed in two orientations and contributes to both width and height.

[0073] The tissue-engaging portion 10E may also have a tissue-engaging surface 20E, which may have a recess 22E when viewed perpendicular to the advancement direction AD2. The tissue-engaging surface 20E also includes a frustoconical surface 49E and a tubular portion 51E. The recess 22E has an upper lip 24E and a lower lip 26E (formed by the top of the frustoconical portion 49E) that help gather tissue as the device 2E advances. The upper lip 24E may form an angle A3 with the advancement direction AD of less than 90 degrees, alternatively between 30 and 70 degrees, when viewed perpendicular to the advancement direction AD. The recess 22E also constitutes a depression 28E, as used herein, which (when viewed perpendicular to the advancement direction) has a depth of at least 50 microns measured perpendicular to a line extending between the upper and lower lips.

[0074] The first and second side walls 14E, 16E extend on opposite lateral sides of the tissue engaging surface 20E. The first and second side walls 14E, 16E may have a height (measured perpendicular to the advancing direction AD) of 500 to 800 microns and a length (measured along the advancing direction AD) of 180 to 220 microns, although any of the ranges described herein may be used and are incorporated herein.

[0075] 21, yet another device 2F for improving aqueous flow within the eye is shown, where like or similar reference numerals refer to like or similar structure, and all features, uses, and characteristics of like structure are incorporated herein. Device 2F includes a body 13E having a tissue-engaging portion 10F substantially similar to that described above, except that it also includes a cutting element 61. Cutting element 61 cuts a circumferential slit in the canal wall as the device advances along the canal wall.

[0076] The device 2F includes a shaft 6F that extends through the introducer 17F, attaches to the handpiece 13 (see FIG. 1A), and operates in the manner described herein. The tissue-engaging portion 10F (formed by the body 12F) can gather tissue, causing it to stretch and tear along the first sidewall 14F and the second sidewall 16F as described herein. The device 2F can also operate without a trabeculohexyl without departing from aspects of the invention that can be implemented with the cutting element 61. The shaft 6F can be made of any suitable material, including metal, including superelastic materials such as Nitinol.

[0077] The device 2F includes a guide member 15F that guides the device 2F along Schlemm's canal. The guide member 15F may be formed by the shaft 6F as shown, or may be part of the body 12F. The body 12F has a first sidewall 14F and a second sidewall 16F on opposite lateral sides of the body 12F. The guide member 15F has an upper surface 18F and a lower surface 20F, and in use, the lower surface 20F slides against the wall of Schlemm's canal. The body 12F includes a torus-shaped tip 75 that connects to a tubular portion 77. The torus-shaped tip 75 tapers downward toward the guide member 15F and then toward the tubular portion 51F.

[0078] 21, 22A, and 22B, the cutting element 61 extends from the lower surface 20F in a radially outward direction defined by the circular shape of the eye (and the central axis CA of the eye). The cutting element 61 is coupled to a tissue-engaging portion along the lower surface 20F that presses against the wall of the tube. The cutting element 61 may be oriented to make a cut that is essentially in a radially outward direction RO relative to the central axis of the eye. The cutting element 61 may be oriented to make a cut at an angle AC within 60 degrees, 30 degrees, or even 15 degrees of the radially outward direction RO defined by the circular shape and the central axis CA of the eye.

[0079] The cutting element 61 can form a continuous slit in the wall of Schlemm's canal to increase its effective size. The effective size increases because the slit increases the potential sealing capacity of the canal. Slits of any length can be formed, and the device can form a continuous slit of at least 45 degrees in Schlemm's canal during use, and may be at least 90 degrees. The cutting element 61 can extend from a surface that slides against the canal wall, which can help stabilize the cutting element 61. The shaft 6F can also generate a spring response, as described herein, which can also provide advantages when advancing the cutting element 61 through the canal wall. The cutting element 61 can be incorporated into any of the other devices described herein and easily positioned with the same relative positions, features, and uses. All such combinations are expressly provided herein, and all uses and characteristics of the cutting element 61 are equally applicable to combination with any of the other devices described herein.

[0080] The cutting element 61 also forms an elongated (circumferential) slit that increases the available surface area for fluid transfer. The slit also effectively shortens the fluid path since the fluid path is generally radially outward and the slit is formed generally radially outward. The method of the present invention can also be performed without removing the trabecular meshwork in an angioplasty procedure. The tissue engaging portion and cutting element are reduced in size and delivered through a cannula to form one or more circumferential slits in the radially outer (scleral) wall. The elongated slit can provide improved fluid flow as a primary angioplasty therapy for the reasons discussed above.

[0081] The tissue-engaging portion 10F may also have a similar structure to other devices described herein, and these similar structures are described herein, with all features of the similar structure of any other device described herein incorporated herein. The tissue-engaging surface 20F may have a recess 22F when viewed perpendicular to the advancement direction AD2. The recess 22F has an upper lip 24F and a lower lip 26F that help gather and compress tissue as the device 2F advances. The upper lip 24F, when viewed perpendicular to the advancement direction AD, may form an angle A3 less than 90 degrees, or an angle between 30 and 70 degrees, with the advancement direction AD. The recess 22F also constitutes a depression 28F, as that term is used herein, when viewed perpendicular to the advancement direction. A first sidewall 14F and a second sidewall 16F extend from the tissue-engaging surface 20F on either side of the tissue-engaging surface 20A. The first sidewall 14F and the second sidewall 16F can have a height, width, and length consistent with the ranges set forth herein incorporated by reference.

[0082] Reference is made to FIG. 25, which is a schematic diagram of one of the devices described herein for purposes of defining further dimensional characteristics. The tissue engaging portion 10 can quickly assume a steep angle AN to gather, compress, and push tissue in an advancing direction AD. The tissue engaging portion 10 may be tightly curved in this region so that the tissue engaging portion 10 quickly assumes a steep angle AN at point P over a relatively short distance D. Of course, a beveled or rounded atraumatic transition T from the guide member 15 may be desirable, but many prior art devices use relatively long ramps that tend to stretch the tissue over the ramp. Such ramps may tend to apply an upward force that may stretch the tissue between the sides, increasing the likelihood that the tissue will separate along a single separation line between the sides, rather than tearing along two sides to remove the tissue as described herein.

[0083] The device of the present invention can have a relatively small height H when the tissue-engaging portion 10 begins to form a relatively steep angle to laterally gather, compress, and subsequently tear tissue. To this end, the body 12 extends proximally from the guide member 15 and has a height H that increases in the proximal direction. When the increasing height reaches 0.014 inches, the tissue-engaging portion 10 increases to an angle AN of 60 degrees relative to the advancing direction within a distance D measured in the advancing direction of 0.035 inches. Alternative ranges are when the height H reaches 0.012 inches, the angle AN reaches 80 degrees within 0.030 inches, or when the height H reaches 0.010 inches, the angle AN reaches 90 degrees within 0.025 inches. Stated differently, the height H2 may be 0.035 or less when the tissue-engaging portion 10 forms an 80-degree angle with respect to the advancing direction AD, and may be 0.027 or less when the tissue-engaging portion 10 forms a 90-degree angle with respect to the advancing direction AD.

[0084] The width W2 of the tissue engaging portion 10 (see FIG. 20) may be moderate in the area where the tissue is gathered. The tissue engaging portion 10 is curved to gather the tissue while allowing sufficient lateral space for the tissue to "drape" around the tissue engaging portion 10 and tear along both sides. The width W2 may be 0.010 inches to 0.0030 inches when the tissue engaging portion 10 increases to an 80-degree angle AN relative to the direction of advancement, and 0.012 inches to 0.0025 inches when the tissue engaging portion 10 increases to an 80-degree angle AN relative to the direction of advancement.

[0085] Use of devices 2 and 2A-2F will now be described with reference to device 2D and FIGS. 22A and 23. An elongated shaft 6D is advanced longitudinally from introducer 17 and through the trabecular meshwork tissue relative to tissue-engaging portion 10D as follows: Device 6D is introduced ab interno into the eye (see FIG. 16). An entrance opening 63 and a first terminal opening 65 are created through the trabecular meshwork into Schlemm's canal using a conventional bladed instrument 67 (see FIG. 22A). Device 2D is then introduced into entrance opening 63 with the introducer extending therein, and device 2D is then advanced toward first terminal opening 65 by extending shaft 6 from handpiece 13 (FIG. 1). As tissue-engaging portion 10D advances, the flexible, curved shaft redirects the tissue-engaging portion to conform to Schlemm's canal. In this manner, the user may not need to substantially change the orientation or position of the handpiece as the tissue-engaging portion advances.

[0086] When the tissue-engaging portion reaches the first end opening 65, a first strip of tissue is released and removed, exposing a portion of the wall of Schlemm's canal. Device 6D can be used to form a second end opening and strip another portion of the trabecular meshwork, exposing more of Schlemm's canal, by advancing the tissue-engaging portion to the second end opening. An entrance opening is formed by removing or dissecting the trabecular meshwork up to or through the outer wall of Schlemm's canal to expose the sclera. The strip of trabecular meshwork released by the device may also be separated (by cutting or tearing) with a separate device or the device itself, as described herein.

[0087] Referring to FIG. 24, the device 2 can include a part-off mechanism 50 for separating the tissue strip from the native tissue. The part-off mechanism 50 can be a loop 52 of material through which the tissue strip is initially guided. The loop is maintained in the open position of FIG. 24 until it is desired to part off the tissue, at which point the loop is tightened (closed) to sever the tissue strip. If a part-off mechanism is provided, it may not be necessary to form an end opening as part of the procedure. The part-off mechanism can also be implemented using a sharp cutting instrument or a separate device without departing from many aspects of the present invention. The part-off mechanism has an actuator coupled to the handpiece, which, upon activation, separates the tissue strip from the native tissue. The loop of material can be a superelastic material such as nitinol. Alternatively, a suture or polymer filament or any other suitable filament or wire can be used. As the tissue engaging portion advances, the tissue strip extends through the loop. The loop closes upon activation of the actuator to sever the tissue strip. The device can also include a suction lumen coupled to the handpiece for removing tissue displaced and released by the device. Of course, the step of parting off the tissue strip may not be necessary when forming the terminal openings.

[0088] As used herein, the term "mobilizing tissue" includes not only blunt engagement to move tissue, but also cutting tissue to move tissue within the path of a tissue-engaging portion. The terms "gathering" tissue and "gathering" tissue shall mean that the tissue gathers into a bundle in front of the tissue-engaging portion. The gathered tissue may be somewhat compressed as it gathers in front of the device. This movement of the gathered tissue advantageously tears / tears / shears the tissue along both sides so that a strip of material is released from the native tissue. The use of a cutting element may create a slit without significantly removing material. Similarly, the use of a rounded tube or element may simply tear the trabecular meshwork open along the seam without significant material removal. The ability of the device of the present invention to collect tissue does not require that the device collect all of the tissue to be removed. The gathered tissue can slide to one side or the other or "over" the tissue-engaging portion, gathering a different portion of the trabecular meshwork to allow the tissue-engaging portion, which tears / tears the tissue, to become free by moving the newly gathered different portion of the trabecular meshwork. The present invention gathers tissue corresponding to the width of the tissue-engaging element; rounded tubes (or cutting elements) cannot gather tissue in this manner.

[0089] The advancement direction as used herein is defined as a local vector that is essentially a circular tangent to Schlemm's canal. Thus, rather than defining a single direction, the advancement direction essentially follows the curvature of Schlemm's canal. All compatible features of any embodiment are intended to be interchangeable with any other embodiment, and all such combinations are expressly incorporated herein. For example, a non-circular cross-sectional shape of the elongate shaft may be used (and claimed) with any of the other embodiments described herein, and the dimensions and properties of any indentation may be attributed to any other indentation. As another example, the shape, stiffness, and properties of a shaft (e.g., shaft 6) described in any embodiment may be used in any of the devices described herein, and all such uses are incorporated herein, whether or not explicitly described. Finally, dimensions and distances are considered averages of particular quantities, where appropriate.

[0090] Additionally, both the non-cutting probe and / or tissue microdisruptor / trabeclohexyl element can have tissue-modulating surface elements on their exterior surfaces that can engage and / or modify the surface of the exterior vessel wall. For example, such elements can include micro-ablation surfaces for cleaning, debridement, and / or thinning of the vessel wall. In addition to the trabeclohexyl configuration, further embodiments of the combined trabeclohexyl and angioplasty device incorporate features designed to alter, modify, scrape, shave, thin, or micro-perforate the vessel wall exterior / contralateral to the TM. This can be achieved through modified surface architectures of the non-smooth ablative guide probe and / or tissue disruptor and / or flexible shaft, including, but not limited to, lattice configurations, notches, and other surface elements designed to manipulate and modify the vessel wall surface as the device moves along the vessel contour. This combined trabeculohexil and angioplasty procedure not only transects and removes the TM, but can also modify and alter the anatomy of the remaining vessel wall to further improve aqueous outflow. Furthermore, in a further embodiment, the surfaces of such ab-interno devices (the guide probe and tissue disruption portion) can be coated with a hemostatic coating (e.g., silver nitrate) that can reduce bleeding during the procedure. While the devices are preferably introduced ab-interno, aspects of the present invention may also be practiced using an ab-external approach without departing from the scope of the present invention. When the devices of the present invention are actuated to lacerate tissue, they preferably do so without cutting or resecting the tissue. Of course, cutting devices, and even cutting elements, can be provided with the devices of the present invention without departing from many aspects of the present invention. The present invention can also be practiced without leaving any implantable structure (including implantable structures coupled to a handpiece) in the eye. Of course, aspects of the present invention can be practiced in conjunction with shunts or stent-like structures without departing from the scope of the present invention.

[0091] As used herein, these terms are often used with reference to illustrations of the device in use and may be modified as explained below to provide further clarification of these terms. The term "advancement direction" may be modified with the term "oriented tangentially relative to the circular shape of the eye." The term "height" may be modified with the term "oriented radially relative to the circular shape of the eye." Similarly, the term "width" may be modified with the terms "oriented perpendicular to the advancement direction and height" or "oriented parallel to the central axis of the eye." Finally, the terms "upper side" or "top surface" and "lower side" or "bottom surface" may be modified with the terms "oriented radially inward relative to the circular shape of the eye" and "oriented radially outward relative to the circular shape of the eye," respectively. The terms referred to above apply equally to circular, tubular, and frustoconical shapes.

[0092] While the device and method have been described with reference to preferred embodiments, various modifications are possible within the scope of the invention. For example, flexible shaft aspects can be used with cutting or ablating elements, or the device can be used with a rigid shaft having an articulating head, without departing from the trabeculohexyl aspects of the invention.

Claims

1. 1. A device for destroying eye tissue, comprising: a distal portion sized and configured for ab interno insertion into the anterior chamber of the eye, an elongated flexible shaft; a distal guide member; and a distal portion including a tissue disruption portion coupled to the shaft proximal to the distal guide member, the tissue disruption portion including protrusions without any cutting elements and a blunt tissue engaging surface; Including, the distal portion is configured to be positioned adjacent to the trabecular meshwork of the eye; The device is configured such that the distal guide member is inserted through the trabecular meshwork into a portion of Schlemm's canal and advanced along the Schlemm's canal of the eye, away from the portion of Schlemm's canal, and as the distal guide member advances along the Schlemm's canal, the tissue engaging surfaces of the protrusions bluntly tear the trabecular meshwork tissue to remove a portion of the inner wall of Schlemm's canal.

2. further comprising an introducer tube including a curved or bent distal portion and a cavity; The device of claim 1 , wherein a portion of the shaft is configured to be inside the cavity of the curved or bent portion during insertion of the distal portion into the anterior chamber.

3. The device of claim 2 , wherein the guide member and the tissue disruption portion are configured to remain distal to the curved or bent portion of the introducer tube during insertion of the distal portion into the anterior chamber.

4. The device of claim 2 , wherein the shaft is configured to advance from the introducer tube to advance the distal guide member along Schlemm's canal.

5. The device of claim 4 , wherein the shaft generates a spring load as the shaft extends from the introducer tube.

6. The device of claim 4 , wherein the shaft exerts a radially outward force against the outer wall of Schlemm's canal as the shaft extends from the introducer tube.

7. The device of claim 4 , wherein the stiffness of the shaft is variable by changing the length of the shaft that extends from the introducer tube.

8. The device of claim 7 , wherein the stiffness of the shaft can vary by at least a factor of 10 as the length of the shaft extending from the introducer tube increases.

9. The device of claim 1 , wherein the device further comprises a proximal portion configured to remain outside the eye when the distal portion is inserted inside the eye.

10. The device of claim 9 , wherein the proximal portion comprises an actuator operably coupled to the shaft, the actuator configured to advance the distal guide member along Schlemm's canal.

11. The apparatus of claim 10 , wherein the actuator comprises a slide.

12. The device of claim 1 , wherein the shaft comprises elasticity.

13. The device of claim 12 , wherein the shaft comprises nitinol.

14. The device of claim 12 , wherein the elasticity of the shaft causes the distal guide member to slide along the inner or outer wall of Schlemm's Canal as the distal guide member is advanced along Schlemm's Canal.

15. The device of claim 1 , wherein the distal guide member comprises a blunt distal portion of the shaft, and further wherein the shaft comprises a wire.

16. The device of claim 1 , wherein the protrusion of the tissue disruption portion protrudes radially inward from the shaft through the trabecular meshwork when the device is in use.

17. The device of claim 1, wherein the tissue disruption portion further comprises a cutting edge disposed radially outward from the shaft, and when the device is in use and the distal guide member advances along the Schlemm's canal, the cutting edge cuts the outer wall of the Schlemm's canal while the protrusion bluntly tears the trabecular meshwork tissue.

18. 10. The device of claim 1, wherein the distal portion of the device includes a cutting element configured to cut the outer wall of Schlemm's canal when the tissue engaging surface of the tissue disruption portion bluntly tears through trabecular meshwork tissue to remove the portion of the inner wall of Schlemm's canal.

19. The device of claim 1 , wherein a portion of the shaft has a curved shape with a radius of curvature of 5 to 9 mm.

20. The device of claim 1 , wherein the distal guide member has a length sufficient to advance from about 30 degrees to 120 degrees of the circumference of Schlemm's canal.

21. 1. A device for increasing aqueous humor drainage of an eye, comprising: Handpiece, an elongated shaft coupled to the handpiece; and a body coupled to the shaft, the body having a tissue engaging portion; a guide member extending distally from the body and configured to be positioned adjacent a wall of Schlemm's canal to guide advancement of the tissue engaging portion in an advancing direction. An apparatus comprising:

22. 22. The device of claim 21, wherein the elongate shaft extends beyond the distal end of the body.

23. 22. The device of claim 21, wherein the elongate shaft extends distally from the tissue engaging portion to form at least a portion of the guide member.

24. The device of claim 21 , wherein the elongate shaft defines a distal end of the guide member.

25. 22. The device of claim 21, wherein the guide member extends distally from the body from 300 to 5000 microns.

26. 22. The apparatus of claim 21, wherein the guide member has an upper surface and a lower surface.

27. 22. The device of claim 21, wherein the lower surface of the guide member slides against the wall of Schlemm's canal.

28. 25. The device of claim 24, wherein the upper surface is configured to gather the tissue as the tissue engaging portion moves through the trabecular meshwork during use.

29. 25. The apparatus of claim 24, wherein the upper surface is spaced from the lower surface by 250 to 550 microns.

30. 25. The apparatus of claim 24, wherein the upper surface is spaced 250 to 450 microns from the lower surface at a center of the upper surface, the center of the upper surface being the farthest portion of the upper surface from the lower surface.

31. 25. The device of claim 24, wherein the upper surface has a radius of curvature of 100 to 350 microns.

32. 25. The device of claim 24, wherein the radius of curvature is between 50 and 300 microns.

33. 25. The device of claim 24, wherein the upper surface is defined at least in part by the elongate shaft.

34. 25. The apparatus of claim 24, wherein the upper surface has a radius of curvature that is smaller than the radius of curvature of the lower surface.

35. 25. The device of claim 24, wherein the upper surface has a convex surface.

36. 25. The device of claim 24, wherein the convex surface of the upper surface is formed by the elongate shaft.

37. 25. The device of claim 24, wherein the lower surface is rounded and has a radius of curvature of 400 to 750 microns when viewed along the direction of advancement.

38. 22. The device of claim 21, wherein the tissue engaging portion has a height measured perpendicular to the direction of advancement.

39. 22. The device of claim 21, wherein the tissue engaging portion has a height of 500 to 800 microns.

40. 22. The device of claim 21, wherein the tissue engaging portion has a height of at least 150 microns.

41. 22. The device of claim 21, wherein the tissue engaging portion has a width measured perpendicular to the direction of advancement, the width being at least 450 microns.

42. 22. The device of claim 21, wherein the width of the tissue engaging portion is between 450 and 850 microns.

43. 22. The device of claim 21, wherein the width of the tissue engaging portion is between 500 and 700 microns.

44. 22. The device of claim 21, wherein the tissue engaging portion has a tissue engaging surface that has a recess when viewed perpendicular to the direction of advancement.

45. 22. The device of claim 21, wherein the recess has an upper lip and a lower lip.

46. 22. The apparatus of claim 21, wherein the upper lip forms an angle of less than 90 degrees with the forward movement direction when viewed perpendicular to the forward movement direction.

47. 22. The device of claim 21, wherein the upper lip forms an angle of between 30 and 70 degrees with the forward movement direction when viewed perpendicular to the forward movement direction.

48. 22. The device of claim 21, wherein the lower lip forms an angle of 0 to 30 degrees with the forward movement direction when viewed perpendicular to the forward movement direction.

49. 22. The device of claim 21, wherein the recess forms a depression when viewed in the advancement direction, the recess having a depth of at least 50 microns.

50. 50. The apparatus of claim 49, wherein the indentation has an indentation depth measured in the advancement direction of at least 100 microns.

51. 50. The apparatus of claim 49, wherein the indentation has an indentation depth measured in the advancement direction of at least 200 microns.

52. 35. The apparatus of claim 34, wherein the depth of the depression is between 300 and 600 microns measured along the direction of advancement.

53. 35. The apparatus of claim 34, wherein the indentation has a indentation height measured perpendicular to the advancement direction and parallel to the central plane, the indentation height being at least 200 microns.

54. 40. The device of claim 39, wherein the height of the depression is between 300 and 600 microns.

55. 35. The apparatus of claim 34, wherein the indentation has an indentation width measured perpendicular to the direction of advancement and the central plane, the indentation width being between 300 and 700 microns.

56. 41. The device of claim 40, wherein the depression has a width of 400 to 600 microns.

57. 35. The device of claim 34, wherein the depression is defined in part by a convex portion of the elongate shaft.

58. 22. The device of claim 21, wherein the shaft extends proximally from the body at an angle greater than 90 degrees relative to the direction of advancement.

59. 22. The device of claim 21, wherein the shaft extends from the tissue engaging element at an angle greater than 135 degrees relative to the direction of advancement.

60. 22. The device of claim 21, wherein the shaft extends from the tissue engaging element at 160 to 200 degrees relative to the direction of advancement.

61. 22. The device of claim 21, wherein the tissue engaging portion has first and second side walls extending from the tissue engaging surface on opposite lateral sides.

62. 22. The device of claim 21, wherein the first sidewall and the second sidewall have a height of at least 150 microns.

63. 22. The apparatus of claim 21, wherein the first sidewall and the second sidewall have a length of 200 to 500 microns, the length being measured along the advancement direction.

64. 。

65. 22. The device of claim 21, wherein the tissue engaging portion defines a central plane in which the direction of advancement lies, and wherein the first sidewall and the second sidewall form an angle with the central plane that is less than 45 degrees.

66. 22. The apparatus of claim 21, wherein the first sidewall and the second sidewall form an angle with the central plane that is less than 20 degrees.

67. 22. The device of claim 21, wherein the tissue engaging portion gathers tissue and displaces the tissue as the tissue engaging portion advances.

68. 22. The device of claim 21, wherein the tissue engaging portion has a blunt engagement with the tissue.

69. 22. The device of claim 21, wherein the tissue engaging portion shears tissue along the first side wall and the second side wall due to movement of tissue gathered by the tissue engaging portion.

70. 22. The device of claim 21, wherein the tissue engaging portion shears the tissue without cutting the tissue.

71. 22. The device of claim 21, wherein the tissue engaging portion compresses and gathers tissue to bunch the tissue in a direction perpendicular to the direction of advancement and in a central plane.

72. 22. The device of claim 21, wherein the tissue engaging portion compresses and gathers tissue while movement of the gathered tissue by the tissue engaging portion causes the tissue to tear along the first and second side walls.

73. 22. The device of claim 21, wherein the tissue engaging portion and shaft are shaped and configured for continuous advancement along Schlemm's canal along an angle of 30 to 120 degrees.

74. 22. The device of claim 21, wherein the shaft is made of a superelastic material.

75. 22. The device of claim 21, wherein the shaft is shaped to provide a curved shape with a radius of curvature of 5.0 to 9.0 mm.

76. 22. The device of claim 21, wherein the shaft is shaped to provide the curved shape extending over 160 to 270 degrees.

77. 22. The device of claim 21, wherein the tissue engaging portion is a blunt non-dissecting probe.

78. 22. The device of claim 21, wherein the tissue engaging portion engages the trabecular meshwork tissue ab-interno, and wherein the tissue engaging portion bluntly transects the trabecular meshwork tissue.

79. 22. The device of claim 21, wherein the tissue engaging portion ablates the inner wall of the Schlemm's canal.

80. 22. The device of claim 21, wherein the tissue engaging portion has a tissue engaging surface proximal to the guide member, the tissue engaging surface contacting and moving the tissue without cutting the tissue, and the tissue engaging surface oriented within 15 degrees of perpendicular to the advancement direction.

81. 22. The device of claim 21, wherein the tissue engaging surface is within 10 degrees of perpendicular to the direction of advancement.

82. 22. The device of claim 21, wherein the tissue engaging surface has a width of at least 400 microns.

83. 22. The device of claim 21, wherein the width of the tissue engaging surface is between 500 and 800 microns.

84. 22. The device of claim 21, wherein the tissue engaging surface has a height of at least 400 microns.

85. 22. The device of claim 21, wherein the tissue engaging surface has a height of at least 500 microns.

86. 22. The device of claim 21, wherein the tissue engaging surface has a height of 550 to 1000 microns.

87. 22. The device of claim 21, wherein the elongate shaft has a cross-sectional shape having a minor axis and a major axis.

88. 22. The device of claim 21, wherein the major axis is within 30 degrees of perpendicular to the central plane.

89. 22. The device of claim 21, wherein the major axis is within 15 degrees of perpendicular to the central plane.

90. 22. The device of claim 21, wherein the major axis is at least 20% larger than the minor axis.

91. 22. The device of claim 21, wherein the minor axis is less than 250 microns and the major axis is greater than 250 microns.

92. 22. The device of claim 21, wherein the elongate shaft is longitudinally advanced to advance the tissue engaging portion through the trabecular meshwork.

93. 22. The device of claim 21, wherein the width of the tissue engaging portion does not pierce tissue.

94. 22. The device of claim 21, wherein the tissue engaging portion is a blunt, non-dissecting probe that does not have a cutting or ablating element.

95. 22. The device of claim 21, wherein the tissue engaging portion bluntly transects the trabecular meshwork tissue.

96. 22. The device of claim 21, wherein the tissue engaging portion ablates the inner wall of the Schlemm's canal in use.

97. 22. The device of claim 21, wherein the tissue engaging portion is configured for introduction into the eye ab interno.

98. 22. The device of claim 21, wherein the tissue engaging portion shears the tissue without a cutting or resecting element.

99. 22. The device of claim 21, wherein the shaft has a curved shape defining a curved surface.

100. 22. The device of claim 21, wherein the shaft conforms to the shape of the Schlemm's canal and defines a plane in which the Schlemm's canal is curved.

101. 22. The apparatus of claim 21, further comprising a handpiece including an introducer having a cavity, the shaft extending through the cavity in the introducer.

102. 22. The device of claim 21, wherein the introducer has a curved tip that is curved from 15 to 60 degrees.

103. 22. The device of claim 21, wherein the distal end of the cavity of the introducer is configured to be inserted into the trabecular meshwork.

104. 102. The device of claim 101, wherein the tissue engaging portion is received within the cavity when the distal end of the cavity is inserted into the trabecular meshwork.

105. 22. The device of claim 21, wherein the shaft is coupled to a handpiece having an actuator, the actuator coupled to the shaft to extend the shaft from the handpiece, and the shaft is curved to naturally change the angle of the tissue engaging portion relative to the handpiece as the shaft extends longitudinally from the handpiece.

106. 22. The device of claim 21, wherein the shaft changes the angle of the tissue engaging portion relative to the hand piece by at least 45 degrees as the shaft extends from the hand piece.

107. 22. The device of claim 21, wherein the shaft is flexible and deforms during use to provide a spring load to the tissue engaging portion.

108. 22. The device of claim 21, wherein the shaft is elastic in the forward direction, the shaft generating the spring load in the forward direction.

109. 22. The device of claim 21, wherein the shaft is elastic in a direction perpendicular to the direction of advancement and in the curved plane.

110. 22. The device of claim 21, wherein the shaft, in use, generates a spring load having a component in the forward-forward direction and a component in a direction radially outward relative to the axis of the eye.

111. 22. The device of claim 21, wherein the shaft is shaped to exert a radially outward force on the tissue against the axis of the eye as the tissue engaging portion moves through the trabecular meshwork.

112. 22. The device of claim 21, wherein the elongate shaft is integrally formed with the tissue engaging portion.

113. 22. The device of claim 21, wherein the elongate shaft is integrally formed with the guide member.

114. The device of claim 21 , wherein the tissue engaging portion is integrally formed with the guide member.

115. 22. The device of claim 21, wherein the elongate shaft comprises a wire.

116. 22. The device of claim 21, wherein the wire has an effective radius of 40 to 400 microns.

117. 22. The device of claim 21, wherein the tissue engaging portion is a bent portion of a wire integrally formed with the elongate shaft.

118. 22. The device of claim 21, wherein the shaft has a curved portion, the bent portion extending inwardly relative to the curved portion from 200 to 800 microns.

119. 22. The device of claim 21, wherein the bent portion forms an angle with the elongate shaft of between 10 and 150 degrees.

120. 22. The device of claim 21, wherein the guide member is integrally formed with the elongate shaft and includes a wire, the guide member having a distal end formed by the wire.

121. 1. A method for improving aqueous humor drainage of an eye, comprising: Providing a device having an elongate shaft and a tissue engaging portion coupled to the elongate shaft; introducing the shaft into the anterior chamber of the eye; positioning the guide member adjacent to a wall of Schlemm's canal; and the method comprising: moving the tissue engaging portion after said positioning to move tissue with the tissue engaging portion.

122. 122. The method of claim 121, wherein the providing is performed using the device having a guide member extending distally from a body, the body being coupled to the shaft.

123. 123. The method of claim 122, wherein the providing is performed with the elongate shaft extending beyond the distal end of the body to form the guide member.

124. 122. The method of claim 121, wherein the providing is performed with the elongate shaft extending distally from the tissue engaging portion to form at least a portion of a guide member, the guide member being positioned within Schlemm's canal during use.

125. 122. The method of claim 121, wherein the providing is performed with the elongate shaft defining the distal end of the guide member.

126. 123. The method of claim 122, wherein the providing is performed with the guide member having an upper surface and a lower surface.

127. 122. The method of claim 121, wherein the moving is performed with the underside of the guide member sliding against the wall of Schlemm's canal.

128. 127. The method of claim 126, wherein the moving is performed while the tissue is gathered by the upper surface.

129. 127. The method of claim 126, wherein said providing is performed with said upper surface spaced 250 to 550 microns from said lower surface.

130. 127. The method of claim 126, wherein said providing is performed with said upper surface spaced 250 to 450 microns from said lower surface at a center of said upper surface, said center of said upper surface being the farthest portion of said upper surface from said lower surface.

131. 127. The method of claim 126, wherein said providing is performed with said upper surface having a radius of curvature of 100 to 350 microns.

132. 127. The method of claim 126, wherein said providing is performed with said upper surface having a radius of curvature of 200 to 300 microns.

133. 127. The method of claim 126, wherein said providing is performed with said upper surface at least partially defined by said elongate shaft.

134. 127. The method of claim 126, wherein said providing is performed with said upper surface having a radius of curvature that is smaller than a radius of curvature of said lower surface.

135. 127. The method of claim 126, wherein the providing is performed with the upper surface having a convex surface.

136. 127. The method of claim 126, wherein the providing is performed with the convex surface formed by the elongate shaft.

137. 127. The method of claim 126, wherein said providing is performed with said lower surface being rounded and having a radius of curvature when viewed along said direction of advancement of between 400 and 750 microns.

138. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a height measured perpendicular to said direction of advancement.

139. 122. The method of claim 121, wherein said providing is performed with said height being between 500 and 800 microns.

140. 122. The method of claim 121, wherein said providing is performed with said height being at least 150 microns.

141. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a width measured perpendicular to said direction of advancement, said width being at least 400 microns.

142. 122. The method of claim 121, wherein said providing is performed with the width of said tissue engaging portion being between 450 and 850 microns.

143. 122. The method of claim 121, wherein said providing is performed with the width of said tissue engaging portion being between 500 and 700 microns.

144. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a tissue engaging surface that is concave when viewed perpendicular to said advancement direction.

145. 122. The method of claim 121, wherein said providing is performed with said recess having an upper lip and a lower lip.

146. 122. The method of claim 121, wherein said providing is performed with said upper lip forming an angle of less than 90 degrees with said forward movement direction when viewed perpendicular to said forward movement direction.

147. 122. The method of claim 121, wherein said providing is performed with said upper lip forming an angle of between 30 and 70 degrees with said forward movement direction when viewed perpendicular to said forward movement direction.

148. 122. The method of claim 121, wherein said providing is performed with said lower lip forming an angle of 0 to 30 degrees with said forward movement direction when viewed perpendicular to said forward movement direction.

149. 122. The method of claim 121, wherein said providing is performed such that said recess forms a depression when viewed perpendicular to said direction of advancement.

150. 150. The method of claim 149, wherein said providing is carried out with said recess having a depth of at least 50 microns measured perpendicular to a line extending between an upper lip and a lower lip of said recess.

151. 150. The method of claim 149, wherein said providing is performed with said indentation having an indentation depth measured in said advancement direction of at least 100 microns, or at least 200 microns.

152. 150. The method of claim 149, wherein the providing is performed with the recess having a depth of 300 to 600 microns.

153. 150. The method of claim 149, wherein said providing is performed such that said indentation has an indentation height measured perpendicular to said advancement direction and parallel to said central plane, said indentation height being at least 200 microns.

154. 154. The method of claim 153, wherein said providing is performed with the depression having a height of 300 to 600 microns.

155. 150. The method of claim 149, wherein said providing is performed with said indentation having an indentation width measured perpendicular to said advancement direction and at said central plane, said indentation width being between 300 and 700 microns.

156. 156. The method of claim 155, wherein said providing is performed with the depression having a width of 400 to 600 microns.

157. 150. The method of claim 149, wherein said providing is performed with said recess being partially defined by said elongate shaft.

158. 122. The method of claim 121, wherein the providing is performed with the shaft extending proximally from the body at an angle greater than 90 degrees.

159. 122. The method of claim 121, wherein said providing is performed with said shaft extending at an angle greater than 135 degrees from said tissue engaging element.

160. 122. The method of claim 121, wherein said providing is performed with said shaft extending from said tissue engaging element at an angle of between 160 and 200 degrees relative to said direction of advancement.

161. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a first sidewall and a second sidewall extending from said tissue engaging surface on opposite lateral sides of said tissue engaging surface.

162. 122. The method of claim 121, wherein said providing comprises: said first sidewall and said second sidewall both having a height of at least 150 microns.

163. 122. The method of claim 121, wherein said providing comprises: said first sidewall and said second sidewall each having a length of 200 to 500 microns, said length being measured along said advancement direction.

164. 122. The method of claim 121, wherein said providing occurs with said first sidewall and said second sidewall forming an angle of less than 45 degrees with said central plane.

165. 122. The method of claim 121, wherein said providing occurs with said first sidewall and said second sidewall forming an angle with said central plane of less than 20 degrees.

166. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion gathering tissue and moving the tissue with the tissue engaging portion.

167. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion gathering tissue and the tissue engaging portion having a blunt engagement with the tissue.

168. 122. The method of claim 121, wherein the moving of the tissue engaging portion is performed in a state that shears tissue along the first side wall and the second side wall due to movement of tissue gathered by the tissue engaging portion.

169. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion moving the tissue so as to tear the tissue without cutting the tissue.

170. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion compressing and gathering the tissue to bunch the tissue in a direction perpendicular to the direction of advancement and in a central plane.

171. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion compressing and gathering tissue while tearing tissue along the first and second side walls due to movement of tissue gathered by the tissue engaging portion.

172. 122. The method of claim 121, wherein the moving is performed continuously to advance along Schlemm's canal along an angle of 30 to 120 degrees.

173. 122. The method of claim 121, wherein said providing is performed with said shaft made from a superelastic material.

174. 122. The method of claim 121, wherein the providing is performed in a state where the shaft is shaped to provide a curved shape with a radius of curvature of 5.0 to 9.0 mm.

175. 122. The method of claim 121, wherein said providing is performed with said shaft being shaped to provide said curved shape extending over 160 to 270 degrees.

176. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion being a blunt non-dissecting probe.

177. 122. The method of claim 121, wherein said moving is performed with said tissue engaging portion moving said trabecular meshwork tissue to bluntly transection said trabecular meshwork tissue.

178. 122. The method of claim 121, wherein the moving is performed in a state in which the tissue engaging portion ablates the inner wall of the Schlemm's canal.

179. 122. The method of claim 121, wherein the providing is performed with the tissue engaging portion having a tissue engaging surface proximal to the guide member, the tissue engaging surface contacting and moving the tissue without cutting the tissue, and the tissue engaging surface oriented within 15 degrees of perpendicular to the advancement direction.

180. 122. The method of claim 121, wherein said providing occurs with said tissue engaging surface within 10 degrees of normal to said direction of advancement.

181. 122. The method of claim 121, wherein said providing is performed with said tissue engaging surface having a width of at least 400 microns.

182. 122. The method of claim 121, wherein said providing is performed with the width of said tissue engaging surface being between 500 and 800 microns.

183. 122. The method of claim 121, wherein said providing is performed with the tissue engaging surface having a height of at least 400 microns.

184. 122. The method of claim 121, wherein said providing is performed with the tissue engaging surface having a height of at least 500 microns.

185. 122. The method of claim 121, wherein said providing is performed with the tissue engaging surface having a height of 550 to 1000 microns.

186. 122. The method of claim 121, wherein said providing is performed with said elongate shaft having a cross-sectional shape with a minor axis and a major axis.

187. 187. The method of claim 186, wherein the providing is performed with the major axis within 30 degrees of perpendicular to the central plane.

188. 187. The method of claim 186, wherein the providing is performed with the major axis within 15 degrees of perpendicular to the central plane.

189. 187. The method of claim 186, wherein the providing is performed with the major axis being at least 20% larger than the minor axis.

190. 187. The method of claim 186, wherein the providing is performed with the minor axis being less than 250 microns and the major axis being greater than 250 microns.

191. 122. The method of claim 121, wherein said moving is performed by longitudinally advancing said elongate shaft to advance said tissue engaging portion through said trabecular meshwork tissue.

192. 122. The method of claim 121, wherein the moving is performed with the tissue engaging portion moving but not piercing the tissue.

193. 122. The method of claim 121, wherein said introducing is performed ab interno.

194. 122. The method of claim 121, wherein said moving is performed without cutting or ablation.

195. 122. The method of claim 121, wherein the providing is performed while the shaft has a curved shape, the curved shape being in a curved plane.

196. 122. The method of claim 121, wherein the moving is performed in a state in which the Schlemm's canal defines a curved plane.

197. 122. The method of claim 121, wherein the providing is performed with the elongate shaft extending through a cavity in an introducer.

198. 122. The method of claim 121, wherein the providing is performed with the introducer having a curved tip that is curved between 15 and 60 degrees.

199. 122. The method of claim 121, further comprising inserting the distal end of the cavity of the introducer into the trabecular meshwork.

200. 200. The method of claim 199, wherein the inserting is performed before the moving, and the tissue engaging portion is contained within the cavity during the inserting.

201. 122. The method of claim 121, wherein the providing is performed with the shaft coupled to a handpiece, and the moving is performed by extending the shaft from the handpiece, the shaft being curved to naturally change the angle of the tissue engaging portion relative to the handpiece.

202. 122. The method of claim 121, wherein said providing is performed with said shaft changing the angle of said tissue engaging portion relative to said hand piece by at least 45 degrees as said shaft extends from said hand piece.

203. 122. The method of claim 121, wherein the providing is performed while the elongate shaft is flexible.

204. 122. The method of claim 121, wherein said providing is performed with said shaft being resilient in said forward direction, said shaft generating a spring load in said forward direction.

205. 122. The method of claim 121, wherein said providing is performed while said shaft is elastic in a direction perpendicular to said advancement direction and is in said curved plane.

206. 122. The method of claim 121, wherein the providing is performed in a state in which the shaft generates a spring load having a component in the forward-forward direction and a component in a radially outward direction relative to the axis of the eye.

207. 122. The method of claim 121, wherein the moving is performed with the shaft shaped to apply a radially outward force to the tissue relative to the axis of the eye during the moving.

208. 122. The method of claim 121, wherein said providing is performed such that said elongate shaft is integrally formed with said tissue engaging portion.

209. 122. The method of claim 121, wherein the providing is performed such that the elongate shaft is integrally formed with the guide member.

210. 122. The method of claim 121, wherein said providing is performed such that said tissue engaging portion is integrally formed with said guide member.

211. 122. The method of claim 121, wherein said providing is performed with said elongate shaft being a wire.

212. 122. The method of claim 121, wherein the providing is performed with the tissue engaging portion being a wire.

213. 122. The method of claim 121, wherein the providing is performed with the wire having an effective radius of 40 to 400 microns.

214. 122. The method of claim 121, wherein the providing step is performed with the tissue engaging portion integrally formed with the elongate shaft, the shaft comprising a wire having a bend that forms with the tissue engaging portion.

215. 122. The method of claim 121, wherein the providing is performed with the shaft having a curved portion, the bent portion extending inwardly relative to the curved portion from 200 to 800 microns.

216. 122. The method of claim 121, wherein said providing is performed with said bent portion forming an angle of 10 to 150 degrees with said elongate shaft.

217. 122. The method of claim 121, wherein the providing is performed with the guide member integrally formed with the elongate shaft, the guide member having a distal end formed by a wire that also forms the elongate shaft.

218. 122. The method of claim 121, wherein the moving is performed with the shaft having a stiffness in the forward direction of less than 20 N / mm.

219. 122. The method of claim 121, wherein the moving is performed using the shaft having a surface that is stiff in a direction perpendicular to the advancement direction and curved less than 20 N / mm to press the body against the eye when moving the tissue engaging portion to move the tissue.

220. 122. The method of claim 121, wherein the moving is performed to divide tissue with trabeculohexyl and the device does not include a cutting or ablating element.

221. 22. The device of claim 21, wherein the shaft has a variable stiffness by changing the length of the shaft that extends from the handpiece.

222. 22. The device of claim 21, wherein the variable stiffness of the shaft changes by at least a factor of 10 when moving between a first actuation position and a second actuation position.

223. 22. The device of claim 21, wherein the shaft has a stiffness in the advancement direction of less than 20 N / mm.

224. 22. The device of claim 21, wherein the shaft has stiffness in a direction perpendicular to the advancement direction and is in the plane of curvature of less than 20 N / mm that presses the body against the eye when moving the tissue engaging portion to displace the tissue.

225. 22. The device of claim 21, wherein the shaft has a variable stiffness by varying the length of the shaft that extends from the handpiece.

226. 22. The device of claim 21, wherein the variable stiffness of the shaft changes by at least a factor of 10 when moving between a first actuation position and a second actuation position.

227. 22. The device of claim 21, wherein the tissue engaging portion does not include a cutting or ablating element such that the tissue is divided by a trabeculohexyl.

228. 22. The device of claim 21, further comprising an aspiration lumen coupled to the handpiece.

229. 22. The device of claim 21, further comprising a part-off mechanism having an actuator coupled to the handpiece, the part-off mechanism separating the tissue strip from the native tissue upon actuation.

230. 230. The device of claim 229, wherein the part-off mechanism comprises a loop through which the tissue strip extends when the tissue engagement portion advances, and the loop closes to cut the tissue strip when the actuator is activated.

231. 122. The method of claim 121, further comprising aspirating the tissue displaced by the tissue engaging portion into an aspiration lumen coupled to the handpiece.

232. 122. The method of claim 121, further comprising separating the tissue strip with a part-off mechanism having an actuator coupled to the handpiece, the part-off mechanism separating the tissue strip from the native tissue when actuated.

233. 233. The method of claim 232, wherein the separating is performed using the part-off mechanism comprising a loop, through which the tissue strip extends as the tissue engagement portion advances, and which closes to cut the tissue strip upon activation of the actuator.

234. 122. The method of claim 121, wherein said providing is performed such that said tissue engaging portion has a width measured perpendicular to said advancement direction, and said moving is performed such that said tissue engaging portion moves said tissue, and said tissue moved by said tissue engaging portion is free to tear from native tissue due to the movement.

235. 122. The method of claim 121, wherein said introducing is performed ab interno.

236. 122. The method of claim 121, wherein the providing is performed without providing or deploying an implantable structure.

237. 22. The device of claim 21, wherein the shaft is configured for ab interno introduction.

238. 22. The device of claim 21, wherein the implantable structure is not coupled to the handpiece.

239. 22. The device of claim 21, wherein the tissue engaging portion has a tissue engaging surface having a height measured perpendicular to the direction of advancement.

240. 240. The device of claim 239, wherein the tissue engaging surface is at least 300 microns in height.

241. 240. The device of claim 239, wherein the tissue engaging surface is 550 to 1200 microns in height.

242. 240. The device of claim 239, wherein the tissue engaging surface is 800 to 1200 microns in height.

243. 22. The device of claim 21, wherein the tissue engaging portion has a tissue engaging surface and a width.

244. 244. The device of claim 243, wherein the width of the tissue engaging portion is measured perpendicular to the advancement direction and radial direction in use.

245. 245. The device of claim 244, wherein the width of the tissue engaging portion is at least 300 microns.

246. 245. The device of claim 244, wherein the width of the tissue engaging portion is between 300 and 700 microns.

247. 22. The device of claim 21, further comprising a suction element coupled to the tissue engaging portion.

248. 248. The device of claim 247, wherein the cutting element is oriented to form a cut that is within 60 degrees of a radially outward direction defined by the circle of the eye.

249. 248. The apparatus of claim 247, further comprising the cutting element being oriented to form a cut that is within 30 degrees of the radially outward direction.

250. 248. The device of claim 247, wherein the cutting element is oriented to form a cut that is within 15 degrees of the radially outward direction.

251. 248. The device of claim 247, further comprising the cutting element being oriented radially outward relative to the central axis of the eye in use.

252. 248. The device of claim 247, further comprising: the cutting element being capable of forming a continuous cut in the wall of Schlemm's canal.

253. 248. The device of claim 247, wherein the cutting element is capable of forming the continuous cut that increases the effective size of Schlemm's canal.

254. 248. The device of claim 247, wherein the cutting element is capable of forming at least a 45 degree uninterrupted severance of Schlemm's canal when in use.

255. 248. The device of claim 247, wherein the cutting element is capable of forming at least a 90 degree uninterrupted severance of Schlemm's canal when in use.

256. 248. The device of claim 247, wherein the cutting element extends outward from a surface of the tissue engaging portion that slides against the vessel wall in use.

257. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a tissue engaging surface, said tissue engaging surface having a height measured perpendicular to the direction of advancement.

258. 258. The method of claim 257, wherein the providing is performed such that the height of the tissue engaging surface is at least 300 microns.

259. 258. The method of claim 257, wherein the providing is performed with the height of the tissue engaging surface being between 550 and 1200 microns.

260. 258. The method of claim 257, wherein the providing is performed with the height of the tissue engaging surface being between 800 and 1200 microns.

261. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a tissue engaging surface having a width.

262. 262. The method of claim 261, wherein the providing is performed with the width measured perpendicular to the forward direction and radial direction in use.

263. 263. The method of claim 262, wherein the providing is performed such that the width of the tissue engaging portion is at least 300 microns.

264. 263. The method of claim 262, wherein the providing is performed with the width of the tissue engaging portion being between 300 and 700 microns.

265. 122. The method of claim 121, further comprising: said providing being performed with said tissue engaging portion including a cutting element.

266. 266. The method of claim 265, wherein the providing is performed with the cutting element oriented to form a cut that is within 60 degrees of a radially outward direction defined by the circle of the eye.

267. 266. The method of claim 265, further comprising: the providing step being performed with the cutting element oriented to form a cut that is within 30 degrees of the radially outward direction.

268. 266. The method of claim 265, wherein the providing is performed with the cutting element oriented to form a cut that is within 15 degrees of the radially outward direction.

269. 266. The method of claim 265, further comprising: the providing step being performed with the cutting element oriented radially outward relative to a central axis of the eye when in use.

270. 266. The method of claim 265, further comprising: the providing step being performed in a state in which the cutting element is capable of forming a continuous cut in the wall of Schlemm's canal.

271. 266. The method of claim 265, wherein the providing is performed in a state in which the cutting element is capable of forming the continuous cut that increases the effective size of Schlemm's canal.

272. 266. The method of claim 265, wherein the providing is performed in a state in which the cutting element is capable of forming an uninterrupted cut along at least 45 degrees of Schlemm's canal when in use.

273. 266. The method of claim 265, wherein the providing is performed in a state in which the cutting element is capable of forming an uninterrupted cut along at least 90 degrees of Schlemm's canal when in use.

274. 266. The method of claim 265, wherein the providing is performed with the cutting element extending outward from a surface of the tissue engaging portion that slides against the vessel wall in use.

275. 22. The device of claim 21, wherein the body extends proximally from the guide member and has a height that increases in the proximal direction to a height of 0.014 inches, and the tissue engaging portion increases to an angle of 60 degrees relative to the advancement direction within a distance measured in the advancement direction of 0.035 inches as the height increases to 0.014 inches.

276. 22. The device of claim 21, wherein the body extends proximally from the guide member and has a height that increases in the proximal direction to a height of 0.012 inches, and the tissue engaging portion increases to an angle of 80 degrees relative to the advancement direction within a distance measured in the advancement direction of 0.030 inches as the height increases to 0.012 inches.

277. 22. The device of claim 21, wherein the body extends proximally from the guide member and has a height that increases in the proximal direction to a height of 0.010 inches, and the tissue engaging portion increases to a 90 degree angle relative to the advancement direction within a distance measured in the advancement direction of 0.025 inches as the height increases to 0.010 inches.

278. 22. The device of claim 21, wherein the tissue engaging portion has a height, the height being less than or equal to 0.035 when the tissue engaging portion forms an 80 degree angle with respect to the direction of advancement.

279. 22. The device of claim 21, wherein the tissue engaging portion has a height, the height being 0.027 or less when the tissue engaging portion forms a 90 degree angle with respect to the direction of advancement.

280. 22. The device of claim 21, wherein the tissue engaging portion has a width of 0.010 to 0.0030 when the tissue engaging portion forms an 80 degree angle with the direction of advancement.

281. 22. The device of claim 21, wherein the tissue engaging portion has a width of 0.012 to 0.0025 when the tissue engaging portion forms a 90 degree angle with respect to the direction of advancement.

282. 122. The method of claim 121, wherein the providing is performed with the body extending proximally from the guide member and having a height that increases in the proximal direction to a height of 0.014 inches, and the tissue engaging portion increasing to an angle of 60 degrees relative to the advancing direction within a distance measured in the advancing direction of 0.035 inches as the height increases to 0.014 inches.

283. 122. The method of claim 121, wherein the providing is performed with the body extending proximally from the guide member and having a height that increases in the proximal direction to a height of 0.012 inches, and the tissue engaging portion increasing to an angle of 80 degrees relative to the advancing direction within a distance measured in the advancing direction of 0.030 inches as the height increases to 0.012 inches.

284. 122. The method of claim 121, wherein the providing is performed with the body extending proximally from the guide member and having a height that increases in the proximal direction to a height of 0.010 inches, and the tissue engaging portion increasing to a 90 degree angle relative to the advancing direction within a distance measured in the advancing direction of 0.025 inches as the height increases to 0.010 inches.

285. 122. The method of claim 121, wherein the providing is performed while the tissue engaging portion has a height, the height being 0.035 or less when the tissue engaging portion forms an 80 degree angle with the advancement direction.

286. 122. The method of claim 121, wherein the providing is performed while the tissue engaging portion has a height, the height being 0.027 or less when the tissue engaging portion forms a 90 degree angle with the advancement direction.

287. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a width of 0.010 to 0.0030 when said tissue engaging portion forms an 80 degree angle with said advancement direction.

288. 122. The method of claim 121, wherein said providing is performed with said tissue engaging portion having a width of 0.012 to 0.0025 when said tissue engaging portion forms a 90 degree angle with respect to said advancement direction.

289. 1. A method of lacerating trabecular meshwork tissue in an eye, comprising: inserting a distal portion of a device into the anterior chamber of the eye, the distal portion including an elongate flexible shaft, a distal guide member, and a tissue disruption portion coupled to the shaft proximal to the distal guide member, the tissue disruption portion including protrusions without any cutting elements and a blunt tissue engaging surface; positioning the distal portion adjacent the trabecular meshwork of the eye; inserting the distal guide member through the trabecular meshwork and into a portion of Schlemm's canal; and advancing the distal guide member along Schlemm's canal away from the portion of Schlemm's canal, wherein the tissue engaging surfaces of the protrusions bluntly lacerate trabecular meshwork tissue as the distal guide member advances along Schlemm's canal, removing a portion of the inner wall of Schlemm's canal.

290. 290. The method of claim 289, wherein the distal portion of the device is inserted ab interno into the anterior chamber.

291. the device further comprising an introducer tube including a curved or bent distal portion and a lumen; The method of claim 289, wherein inserting the distal portion of the device includes inserting the curved or bent distal portion of the introducer tube into the anterior chamber, and further wherein a portion of the shaft is within the cavity of the curved or bent portion during the insertion.

292. 292. The method of claim 291, wherein the guide member and the tissue disruption portion remain distal to the curved or bent portion of the introducer tube during the insertion into the anterior chamber.

293. 292. The method of claim 291, wherein advancing the distal guide member along Schlemm's canal comprises extending the shaft from the introducer tube and advancing the distal guide member along Schlemm's canal.

294. 294. The method of claim 293, wherein the shaft generates a spring load as the shaft extends from the introducer tube.

295. 294. The method of claim 293, wherein the shaft exerts a radially outward force against the outer wall of Schlemm's canal as the shaft extends from the introducer tube.

296. 294. The method of claim 293, further comprising varying the stiffness of the shaft by changing the length of the shaft extending from the introducer tube.

297. 297. The method of claim 296, wherein the stiffness of the shaft can vary by at least 10 times as the length of the shaft extending from the introducer tube increases.

298. 290. The method of claim 289, wherein the device further comprises a proximal portion that remains outside the eye.

299. 299. The method of claim 298, wherein the proximal portion comprises an actuator operably coupled to the shaft, and the method further comprises operating the actuator to advance the distal guide member along Schlemm's canal.

300. 300. The method of claim 299, wherein the actuator comprises a slide, and the method further comprises moving the slide to advance the distal guide member along Schlemm's canal.

301. 294. The method of claim 293, further comprising moving a slide to extend the shaft from the introducer tube and advance the distal guide member along Schlemm's canal.

302. 302. The method of claim 301, further comprising retracting the slide to retract the distal guide member toward the introducer tube.

303. 290. The method of claim 289, wherein the shaft comprises elasticity.

304. 304. The method of claim 303, wherein the shaft comprises nitinol.

305. 304. The method of claim 303, wherein the elasticity of the shaft causes the distal guide member to slide along the inner or outer wall of Schlemm's canal during the advancement along Schlemm's canal.

306. 290. The method of claim 289, wherein the distal guide member comprises a blunt distal portion of the shaft, and further wherein the shaft comprises a wire.

307. 290. The method of claim 289, wherein when the device is in use, the protrusion of the tissue destruction portion protrudes radially inward from the shaft through the trabecular meshwork.

308. The method of claim 307, wherein when the device is in use, the tissue destruction portion further includes a cutting edge positioned radially outward from the shaft, and the method further includes cutting the outer wall of Schlemm's canal with the cutting element as the distal guide member advances along Schlemm's canal.

309. The method of claim 289, further comprising severing the trabecular meshwork tissue from attachment to other ocular tissue with the blunt tissue engaging surface of the tissue disruption portion as the distal guide member advances along Schlemm's canal.

310. The method of claim 289, wherein the distal portion of the device includes a cutting element, and the method further comprises removing a portion of the inner wall of Schlemm's canal and cutting the outer wall of Schlemm's canal with the cutting element when the tissue engaging surface of the tissue disruption portion bluntly tears through trabecular meshwork tissue to remove the portion of the inner wall of Schlemm's canal.

311. 311. The method of claim 310, wherein cutting the outer wall of Schlemm's canal forms a continuous slit in the outer wall of Schlemm's canal.

312. The method of claim 310, wherein cutting the outer wall of Schlemm's canal increases the effective size of Schlemm's canal.

313. 290. The method of claim 289, further comprising removing the distal portion of the device from the eye without deploying or providing any implantable structure with the device.

314. 290. The method of claim 289, wherein a portion of the shaft has a curved shape with a radius of curvature of 5 to 9 mm.

315. 290. The method of claim 289, wherein advancing the distal guide member along Schlemm's canal comprises advancing the distal guide member to approximately 30 to 120 degrees of the circumference of Schlemm's canal.

316. 1. A method of performing a procedure on an eye of a patient, comprising: advancing a portion of the medical device at least partially inserted into Schlemm's canal along Schlemm's canal; and During said advancement along said Schlemm's canal, bluntly tearing or transection of the trabecular meshwork without cutting; Cutting, slitting, grinding, shaving, debridement, or microperforation of the outer wall of Schlemm's canal A method that includes both.

317. 317. The method of claim 316, wherein the procedure is performed without deploying or placing any implantable structure.

318. 317. The method of claim 316, wherein the portion of the medical device includes a guide member inserted into Schlemm's canal.

319. 1. A method of destroying eye tissue, comprising: inserting a distal portion of a device into the anterior chamber of the eye, the distal portion including an elongate flexible shaft, a distal guide member, and a tissue disruption portion coupled to the shaft proximal to the distal guide member, the tissue disruption portion including a protrusion extending radially inward from the shaft and a cutting edge disposed radially outward from the shaft, the protrusion including a blunt tissue engaging surface devoid of any cutting element; positioning the distal portion adjacent the trabecular meshwork of the eye; inserting the distal guide member through the trabecular meshwork and into a portion of Schlemm's canal; and advancing the distal guide member along Schlemm's canal away from the portion of Schlemm's canal. Including, As the distal guide member advances along Schlemm's Canal, the tissue engaging surfaces of the protrusions bluntly tear through the trabecular meshwork tissue to remove a portion of the inner wall of Schlemm's Canal, while the cutting edges simultaneously cut through the outer wall of Schlemm's Canal.

320. 320. The method of claim 319, wherein the distal portion of the device is inserted ab interno into the anterior chamber.

321. the device further comprising an introducer tube including a curved or bent distal portion and a lumen; 320. The method of claim 319, wherein inserting the distal portion of the device comprises inserting the curved or bent distal portion of the introducer tube into the anterior chamber, and further wherein a portion of the shaft is within the cavity of the curved or bent portion during the insertion.

322. 322. The method of claim 321, wherein the guide member and the tissue disruption portion remain distal to the curved or bent portion of the introducer tube during the insertion into the anterior chamber.

323. 322. The method of claim 321, wherein advancing the distal guide member along Schlemm's canal comprises extending the shaft from the introducer tube to advance the distal guide member along Schlemm's canal.

324. 324. The method of claim 323, wherein the shaft generates a spring load as the shaft extends from the introducer tube.

325. 324. The method of claim 323, wherein the shaft exerts a radially outward force against the outer wall of Schlemm's canal as the shaft extends from the introducer tube.

326. 324. The method of claim 323, further comprising varying the stiffness of the shaft by changing the length of the shaft extending from the introducer tube.

327. 327. The method of claim 326, wherein the stiffness of the shaft can vary by at least 10 times as the length of the shaft extending from the introducer tube increases.

328. 320. The method of claim 319, wherein the device further comprises a proximal portion that remains outside the eye.

329. 329. The method of claim 328, wherein the proximal portion comprises an actuator operably coupled to the shaft, the method further comprising operating the actuator to advance the distal guide member along Schlemm's canal.

330. 330. The method of claim 329, wherein the actuator comprises a slide, and the method further comprises moving the slide to advance the distal guide member along Schlemm's canal.

331. 324. The method of claim 323, further comprising moving a slide to extend the shaft from the introducer tube and advance the distal guide member along Schlemm's canal.

332. 332. The method of claim 331, further comprising retracting the slide to retract the distal guide member toward the introducer tube.

333. 320. The method of claim 319, wherein the shaft comprises elasticity.

334. The method of claim 333, wherein the shaft comprises nitinol.

335. 334. The method of claim 333, wherein the elasticity of the shaft causes the distal guide member to slide along the inner or outer wall of Schlemm's canal during the advancement along Schlemm's canal.

336. 320. The method of claim 319, wherein the distal guide member comprises a blunt distal portion of the shaft, and further wherein the shaft comprises a wire.

337. The method of claim 319, further comprising severing the trabecular meshwork tissue from attachment to other ocular tissue with the blunt tissue engaging surface of the tissue disruption portion as the distal guide member advances along Schlemm's canal.

338. 320. The method of claim 319, wherein cutting the outer wall of Schlemm's canal forms a continuous slit in the outer wall of Schlemm's canal.

339. 320. The method of claim 319, wherein cutting the outer wall of Schlemm's canal increases the effective size of Schlemm's canal.

340. 320. The method of claim 319, further comprising removing the distal portion of the device from the eye without deploying or providing any implantable structure with the device.

341. 320. The method of claim 319, wherein a portion of the shaft has a curved shape with a radius of curvature of 5 to 9 mm.

342. 320. The method of claim 319, wherein advancing the distal guide member along Schlemm's canal comprises advancing the distal guide member to approximately 30 to 120 degrees of the circumference of Schlemm's canal.

343. The method of claim 319, wherein the outer wall of Schlemm's canal includes the sclera, and further wherein the cutting edge of the tissue disruption portion forms an elongated slit in the outer wall to thin the sclera as the distal guide member advances along Schlemm's canal.

344. 320. The method of claim 319, wherein the advancing along Schlemm's canal includes following the circumferential contour of Schlemm's canal.

345. 320. The method of claim 319, wherein the elongate flexible shaft applies a radially outward force against the outer wall of Schlemm's canal as the distal guide member advances along Schlemm's canal.

346. 1. A method of performing a procedure on an eye of a patient, comprising: advancing a portion of the medical device at least partially inserted into Schlemm's canal along Schlemm's canal; and During said advancement along Schlemm's canal, Bluntly tearing or transection of the trabecular meshwork tissue without cutting, and simultaneously Cutting, slitting, grinding, shaving, debridement, or microperforation of the outer wall of Schlemm's canal A method that includes both.

347. 347. The method of claim 346, wherein the procedure is performed without deploying or placing any implantable structure.

348. The method of claim 346, wherein the portion of the medical device includes a guide member inserted into Schlemm's canal.

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