Devices for deploying intraocular shunts

Abstract

The present invention generally relates to devices for deploying intraocular shunts without the use of an optical apparatus that contacts an eye, such as a goniolens. In certain embodiments, devices of the invention include a housing, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled inside the housing to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt, and the device includes an insertion configuration and a deployment configuration and the insertion configuration involves the shaft being fully disposed within the housing.

Description

FIELD OF THE INVENTION

The present invention generally relates to devices for deploying intraocular shunts without the use of an optical apparatus that contacts an eye, such as a goniolens.

BACKGROUND

Glaucoma is a disease of the eye that affects millions of people. Glaucoma is associated with an increase in intraocular pressure resulting either from a failure of a drainage system of an eye to adequately remove aqueous humor from an anterior chamber of the eye or overproduction of aqueous humor by a ciliary body in the eye. Build-up of aqueous humor and resulting intraocular pressure may result in irreversible damage to the optic nerve and the retina, which may lead to irreversible retinal damage and blindness.

Glaucoma may be treated by surgical intervention that involves placing a shunt in the eye to result in production of fluid flow pathways between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). Such fluid flow pathways allow for aqueous humor to exit the anterior chamber. Generally, the surgical intervention to implant the shunt involves inserting into the eye a delivery device that holds an intraocular shunt, and deploying the shunt within the eye. A delivery device holding the shunt enters the eye through a cornea (ab interno approach), and is advanced across the anterior chamber. The delivery device is advanced through the sclera until a distal portion of the device is in proximity to a drainage structure of the eye. The shunt is then deployed from the delivery device, producing a conduit between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). See for example, Yu et al. (U.S. Pat. No. 6,544,249 and U.S. patent application number 2008/0108933) and Prywes (U.S. Pat. No. 6,007,511).

Such a surgical procedure requires an optical apparatus, such as a goniolens, so that a surgeon may visualize the delivery device within the eye and ensure proper placement of the shunt after it has been deployed from the delivery device.

SUMMARY

The present invention generally relates to devices for deploying intraocular shunts from a delivery device without use of an optical apparatus that contacts the eye, preferably without use of any optical apparatus. Devices of the invention accomplish shunt deployment without use of an optical apparatus by having a biased distal portion, such that upon entry of the distal portion of the device into an anterior chamber of an eye, the distal portion slides to fit within the anterior chamber angle of the eye. A resistance feedback feature of the device informs an operator that the deployment device is properly positioned within the anterior chamber angle of the eye for deployment and proper placement of the shunt within the eye.

In certain embodiments, devices of the invention include a housing having an angled distal end, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. Devices of the invention may further include an intraocular shunt that is at least partially disposed within the shaft. In particular embodiments, the angle of the distal end is substantially identical to an anterior chamber angle of an eye.

The housing of devices of the invention may include a proximal portion and a distal portion. In certain embodiments, the distal portion of the housing is movable within the proximal portion of the housing. The housing may further include a member that limits axial retraction of the distal portion of the housing. In certain embodiments, the distal portion includes a capsule and a sleeve. In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.

Devices of the invention include numerous configurations, such as an insertion configuration, a shaft exposure configuration, and a deployment configuration. The insertion configuration includes the hollow shaft fully disposed within the sleeve. The shaft exposure configuration includes retraction of the capsule to at least partially within the proximal portion of the housing, thereby exposing a distal portion of the hollow shaft from the sleeve.

The deployment configuration involves engagement of the deployment mechanism. In certain embodiments, the deployment mechanism may include a two stage system. The first stage is a pusher component and the second stage is a retraction component. Rotation of the deployment mechanism sequentially engages the pusher component and then the retraction component. The pusher component pushes the shunt to partially deploy the shunt from within the shaft, and the retraction component retracts the shaft from around the shunt. The deployment mechanism further includes at least one member that limits axial movement of the shaft.

The hollow shaft of the deployment device may have various shapes and sizes. In certain embodiments, a distal end of the shaft is beveled. In particular embodiments, the bevel is a double bevel. In certain embodiments, the angle of the bevel is such that upon insertion of the shaft through the sclera of an eye, the bevel is substantially parallel with the conjunctiva of an eye. In certain embodiments, the hollow shaft is a needle.

Devices of the invention may be completely automated, partially automated, or completely manual. Devices of the invention may be connected to larger robotic systems or may be used as stand alone handheld deployment devices. In particular embodiments, the device is a handheld device.

Devices of the invention may include an indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator know in the art, for example a visual indicator, an audio indicator, or a tactile indicator. In certain embodiments, the indicator is a visual indicator.

Other aspects of the invention provide devices for deploying an intraocular shunt that include a housing, in which a distal end of the housing includes a protrusion, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. The devices may further include an intraocular shunt that is at least partially disposed within the shaft.

The housing of devices of the invention may include a proximal portion and a distal portion. In certain embodiments, the distal portion of the housing is movable within the proximal portion of the housing. The housing may further include a member that limits axial retraction of the distal portion of the housing. In certain embodiments, the distal portion includes a capsule and a sleeve. In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.

Devices of the invention include numerous configurations, such as an insertion configuration, a shaft exposure configuration, and a deployment configuration. The insertion configuration includes the hollow shaft fully disposed within the sleeve. The shaft exposure configuration includes retraction of the capsule to at least partially within the proximal portion of the housing, thereby exposing a distal portion of the hollow shaft from the sleeve.

The deployment configuration involves engagement of the deployment mechanism. In certain embodiments, the deployment mechanism may include a two stage system. The first stage is a pusher component and the second stage is a retraction component. Rotation of the deployment mechanism sequentially engages the pusher component and then the retraction component. The pusher component pushes the shunt to partially deploy the shunt from within the shaft, and the retraction component retracts the shaft from around the shunt. The deployment mechanism further includes at least one member that limits axial movement of the shaft.

The hollow shaft of the deployment device may have various shapes and sizes. In certain embodiments, a distal end of the shaft is beveled. In particular embodiments, the bevel is a double bevel. In certain embodiments, the angle of the bevel is such that upon insertion of the shaft through the sclera of an eye, the bevel is substantially parallel with the conjunctiva of an eye. In certain embodiments, the hollow shaft is a needle.

Devices of the invention may be completely automated, partially automated, or completely manual. Devices of the invention may be connected to larger robotic systems or may be used as stand alone handheld deployment devices. In particular embodiments, the device is a handheld device.

Devices of the invention may include an indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator know in the art, for example a visual indicator, an audio indicator, or a tactile indicator. In certain embodiments, the indicator is a visual indicator.

Another aspect of the invention provides devices for deploying an intraocular shunt that include a deployment mechanism, a hollow shaft coupled to the deployment mechanism and configured to hold an intraocular shunt, and a member adapted to provide resistance feedback to an operator upon a distal portion of the device contacting an anatomical feature of the eye, such as the sclera. The resistance feedback indicates to an operator that a distal portion of the device is properly positioned to deploy the shunt.

Another aspect of the invention provides devices for deploying an intraocular shunt that include a deployment mechanism, a hollow shaft coupled to the deployment mechanism and configured to hold an intraocular shunt, and means for providing feedback to an operator advancing the shaft. The feedback indicates to an operator that a distal portion of the shaft is properly positioned to deploy the shunt. In certain embodiments, the feedback is resistance feedback.

Other aspects of the invention provide devices for deploying an intraocular shunt including a housing having a proximal portion and a distal portion, in which the distal portion is movable within the proximal portion, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. The devices may further include an intraocular shunt that is at least partially disposed within the shaft. The housing may further include a member that limits axial retraction of the distal portion of the housing.

In certain embodiments, the distal portion includes a capsule and a sleeve. In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.

Devices of the invention include numerous configurations, such as an insertion configuration, a shaft exposure configuration, and a deployment configuration. The insertion configuration includes the hollow shaft fully disposed within the sleeve. The shaft exposure configuration includes retraction of the capsule to at least partially within the proximal portion of the housing, thereby exposing a distal portion of the hollow shaft from the sleeve.

The deployment configuration involves engagement of the deployment mechanism. In certain embodiments, the deployment mechanism may include a two stage system. The first stage is a pusher component and the second stage is a retraction component. Rotation of the deployment mechanism sequentially engages the pusher component and then the retraction component. The pusher component pushes the shunt to partially deploy the shunt from within the shaft, and the retraction component retracts the shaft from around the shunt. The deployment mechanism further includes at least one member that limits axial movement of the shaft.

The hollow shaft of the deployment device may have various shapes and sizes. In certain embodiments, a distal end of the shaft is beveled. In particular embodiments, the bevel is a double bevel. In certain embodiments, the angle of the bevel is such that upon insertion of the shaft through the sclera of an eye, the bevel is substantially parallel with the conjunctiva of an eye. In certain embodiments, the hollow shaft is a needle.

Devices of the invention may be completely automated, partially automated, or completely manual. Devices of the invention may be connected to larger robotic systems or may be used as stand alone handheld deployment devices. In particular embodiments, the device is a handheld device.

Devices of the invention may include an indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator know in the art, for example a visual indicator, an audio indicator, or a tactile indicator. In certain embodiments, the indicator is a visual indicator.

Other aspects of the invention provide devices for deploying an intraocular shunt including a housing, a deployment mechanism at least partially disposed within the housing, and a hollow shaft coupled inside the housing to the deployment mechanism, in which the shaft is configured to hold an intraocular shunt. These devices include an insertion configuration and a deployment configuration and the insertion configuration involves the shaft being fully disposed within the housing. The devices may further include an intraocular shunt that is at least partially disposed within the shaft.

The housing of devices of the invention may include a proximal portion and a distal portion. In certain embodiments, the distal portion of the housing is movable within the proximal portion of the housing. The housing may further include a member that limits axial retraction of the distal portion of the housing. In certain embodiments, the distal portion includes a capsule and a sleeve. In other embodiments, a distal end of the sleeve further includes a protrusion. The protrusion may be formed integrally with the distal end of the sleeve or may be connected to a distal end of the sleeve. The protrusion may surround the distal end of the sleeve, or the protrusion may extend around only a portion of the sleeve. In certain embodiments, the protrusion is a collar that surrounds the distal end of the sleeve. In other embodiments, the protrusion includes a flat bottom portion and an angled top portion. In particular embodiments, the angle of the top portion is substantially identical to an anterior chamber angle of an eye.

Devices of the invention also include a shaft exposure configuration. The shaft exposure configuration includes retraction of the capsule to at least partially within the proximal portion of the housing, thereby exposing a distal portion of the hollow shaft from the sleeve. The deployment configuration involves engagement of the deployment mechanism. In certain embodiments, the deployment mechanism may include a two stage system. The first stage is a pusher component and the second stage is a retraction component. Rotation of the deployment mechanism sequentially engages the pusher component and then the retraction component. The pusher component pushes the shunt to partially deploy the shunt from within the shaft, and the retraction component retracts the shaft from around the shunt. The deployment mechanism further includes at least one member that limits axial movement of the shaft.

The hollow shaft of the deployment device may have various shapes and sizes. In certain embodiments, a distal end of the shaft is beveled. In particular embodiments, the bevel is a double bevel. In certain embodiments, the angle of the bevel is such that upon insertion of the shaft through the sclera of an eye, the bevel is substantially parallel with the conjunctiva of an eye. In certain embodiments, the hollow shaft is a needle.

Devices of the invention may be completely automated, partially automated, or completely manual. Devices of the invention may be connected to larger robotic systems or may be used as stand alone handheld deployment devices. In particular embodiments, the device is a handheld device.

Devices of the invention may include an indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator know in the art, for example a visual indicator, an audio indicator, or a tactile indicator. In certain embodiments, the indicator is a visual indicator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic showing an embodiment of a shunt deployment device according to the invention. FIG. 1B shows a cross sectional view of the device of FIG. 1. In this figure, the distal portion of the housing is extended from the proximal portion of the housing. FIG. 1C shows a cross sectional view of the device of FIG. 1. In this figure, the distal portion of the housing is retracted within the proximal portion of the housing. FIG. 1D is a schematic showing an enlarged view of a protrusion on a distal end of a distal portion of a housing of the device of FIG. 1A. In this figure, a bottom portion of the protrusion is flat and a top portion of the protrusion is angled.

FIGS. 2A-2C are schematics showing an enlarged view of a protrusion on a distal end of a distal portion of a housing of devices of the invention. FIG. 2B is a side view of the protrusion shown in FIG. 2A. FIG. 2C is a top view of the protrusion shown in FIG. 2A.

FIG. 3A shows a deployment device in an insertion configuration and fit into an anterior chamber of an eye. FIG. 3B shows a deployment device in an insertion configuration and inserted at too shallow an angled, thus abutting the sclera above the anterior chamber angle. FIG. 3C shows a deployment device in an insertion configuration after the protrusion has caused the device to slide down the sclera and be fit into an anterior chamber of an eye. FIG. 3D shows a deployment device in an insertion configuration and inserted at too steep an angled, thus abutting the iris below the anterior chamber angle. FIG. 3E shows a deployment device in an insertion configuration after the protrusion has caused the device to deflect off of the iris and slide along the iris and be fit into an anterior chamber of an eye.

FIG. 4 shows an exploded view of the device shown in FIG. 1.

FIGS. 5A to 5D are schematics showing different enlarged views of the deployment mechanism of the deployment device.

FIGS. 6A to 6C are schematics showing interaction of the deployment mechanism with a portion of the housing of the deployment device.

FIG. 7 depicts a schematic of an exemplary intraocular shunt.

FIG. 8 shows a cross sectional view of the deployment mechanism of the deployment device.

FIG. 9A is a schematic showing deployment devices of the invention in a pre-deployment or insertion configuration. FIG. 9B shows an enlarged view of the distal portion of the deployment device of FIG. 9A. This figure shows an intraocular shunt loaded within a hollow shaft of the deployment device and that the shaft is completely disposed within the sleeve of the housing. FIG. 9C show a schematic of the deployment mechanism in a pre-deployment or insertion configuration. FIG. 9D is another schematic showing deployment devices of the invention in a pre-deployment or insertion configuration.

FIG. 10 is a schematic showing insertion of a device of the invention into an anterior chamber of the eye. This figure also shows the sleeve and protrusion fitted within an anterior chamber angle of the eye.

FIG. 11 is a schematic showing extension of the shaft from within the sleeve, which is accomplished by partial retraction of the distal portion of housing to within the proximal portion of housing.

FIGS. 12A and 12B show schematics of the deployment mechanism at the end of the first stage of deployment of the shunt from the deployment device. FIG. 12C shows an enlarged view of the distal portion of the deployment device of FIG. 12A. This figure shows an intraocular shunt partially deployed from within a hollow shaft of the deployment device.

FIG. 13 is a schematic showing the deployment device after completion of the first stage of deployment of the shunt from the device and in to the eye.

FIG. 14A show a schematic of the deployment mechanism at the end of the second stage of deployment. FIG. 14B shows a schematic of the deployment device at the end of the second stage of deployment. FIG. 14C shows another view of the deployment device at the end of the second stage of deployment.

FIG. 15 is a schematic showing the deployment device after completion of deployment of the shunt from the device and in to the eye.

DETAILED DESCRIPTION

Reference is now made to FIG. 1A which shows an embodiment of a shunt deployment device 100 according to the invention. While FIG. 1 shows a handheld manually operated shunt deployment device, it will be appreciated that devices of the invention may be coupled with robotic systems and may be completely or partially automated. As shown in FIG. 1A deployment device 100 includes a generally cylindrical body or housing 101, however, the body shape of housing 101 could be other than cylindrical. Housing 101 may have an ergonomical shape, allowing for comfortable grasping by an operator. Housing 101 is shown with optional grooves 102 to allow for easier gripping by a surgeon.

FIG. 1B shows a cross sectional view of device 100. This figure shows that housing 101 includes a proximal portion 101a and a distal portion 101b. The distal portion 101b is movable within proximal portion 101a. In this figure, spring mechanism 120 includes a spring 121 that controls movement of distal portion 101b. Spring mechanism 120 further includes a member 122 that acts as a stopper and limits axial retraction of distal portion 101b within proximal portion 101a. Spring mechanism 120 further includes members 123 and 124 that run the length of spring 121. The ends of members 123 and 124 include flanges 125 and 126 that project inward from members 123 and 124. An end of distal portion 101b includes flanges 127 and 128 that project outward from distal portion 101b. Flanges 125 and 126 interact with flanges 127 and 128 to prevent release of distal portion 101b from proximal portion 101a. The flanges 125 and 126 and 127 and 128 hold the distal portion 101b in an extended position until a compressive force acts upon distal portion 101b, thereby causing distal portion 101b to partially retract within proximal portion 101a.

Distal portion 101b includes a capsule 129 and a hollow sleeve 130. Capsule 129 and sleeve 130 may be formed integrally or may be separate components that are coupled or connected to each other. The hollow sleeve 130 is configured for insertion into an eye and to extend into an anterior chamber of an eye. FIG. 1B shows distal portion 101b of housing 101 extended from proximal portion 101a of housing 101. In this configuration, hollow shaft 104 (not shown in this figure) is completely disposed within sleeve 130. FIG. 1C shows distal portion 101b of housing 101 retracted within proximal portion 101a of housing 101. Retraction of distal portion 101b of housing 101 within proximal portion 101a of housing 101 exposes hollow shaft 104, which is discussed in greater detail below.

A distal end of sleeve 130 includes a protrusion 131 (FIG. 1D). Protrusion 131 provides resistance feedback to an operator as the operator is advancing the sleeve 130 through an anterior chamber of an eye. In a standard ab interno approach (see for example Yu et al. U.S. Pat. No. 6,544,249 and U.S. patent application number 2008/0108933) a deployment device holding a shunt enters an eye through a cornea. The deployment device is advanced across the anterior chamber in what is referred to as a transpupil implant insertion. The deployment device is advanced to the sclera on the opposite side of the eye from which the device entered the eye. With devices of the invention, upon advancement of the device 100 across an anterior chamber of the eye, the protrusion 131 at the distal end of the hollow sleeve 130 will contact the sclera, providing resistance feedback to an operator that no further advancement of the device 100 is necessary. This feedback also informs the operator that the device 100 is in proper position for exposure of the hollow shaft 104, which will advance through the sclera for deployment of an intraocular shunt. The protrusion 131, provides adequate surface area at the distal end of sleeve 130, thus preventing sleeve 130 from entering the sclera.

In certain embodiments, protrusion 131 has a substantially flat bottom portion and an angled top portion (FIG. 1D). In other embodiments, protrusion 131 has a slightly tapered top and a slightly tapered bottom with a rounded distal portion (FIGS. 2A-2C).

Referring back to FIG. 1D, the angle of the top portion is substantially identical to an anterior chamber angle of an eye. Such a shape of the protrusion ensures that the device of the invention will also finds its way to fit into the anterior chamber angle of the eye, the place for proper deployment of an intraocular shunt. This is explained with reference to FIGS. 3A to 3E. FIG. 3A shows device 100 in an insertion configuration and inserted into an eye 140. In this figure, protrusion 131 at the distal end of the sleeve 130 has been advanced across the anterior chamber 141 to the sclera 142 on the opposite side of the eye 140 from which the device entered the eye 140. FIG. 3A shows protrusion 131 fitted within the anterior chamber angle 143 of the eye 140. If sleeve 130 enters the anterior chamber 141 at too shallow an angle, i.e., the protrusion 131 hit the sclera 142 above the anterior chamber angle 143, the angled top portion of the protrusion 131 causes the sleeve 130 to slide down the sclera 142 (direction of arrow) until the protrusion 131 is fit within the anterior chamber angle 143 of the eye 140 (FIGS. 3B and 3C). The sleeve 130 will slide down the sclera 142 instead of entering the sclera 142 at the contact point because the shaft 104 is completely disposed within the sleeve 130 and the protrusion 131 provides adequate surface area at the distal end of sleeve 130 to prevent enough force from being generated at the distal end of sleeve 130 that would result in sleeve 130 entering the sclera 142.

Conversely, if sleeve 130 enters the anterior chamber 141 at too steep an angle, i.e., the protrusion 131 hit the iris 144 below the anterior chamber angle 143, the substantially flat bottom portion of the protrusion 131 causes the sleeve 130 to deflect off the iris 144 and proceed is a direction parallel to the iris 144 until the protrusion 131 is fit within the anterior chamber angle 143 of the eye 140 (FIGS. 3D and 3E). The sleeve 130 will deflect off the iris 144 instead of entering the iris 144 at the contact point because the shaft 104 is completely disposed within the sleeve 130 and the protrusion 131 provides adequate surface area at the distal end of sleeve 130 to prevent enough force from being generated at the distal end of sleeve 130 that would result in sleeve 130 entering the iris 144.

In certain embodiments, protrusion 131 is not required. In these embodiments, the sleeve 130 is of a sufficient outer diameter such that the sleeve itself may serve the function of the protrusion as described above. In these embodiments, a distal end of the sleeve is shaped to have a flat bottom portion and an angled top portion.

Referring back to FIG. 1A, the proximal portion 101a of the housing 101 is open at its proximal end, such that a portion of a deployment mechanism 103 may extend from the proximal end of the proximal portion 101a of the housing 101. The sleeve 130 of the distal portion 101b of the housing 101 is also open such that at least a portion of a hollow shaft 104 may extend inside the housing, into sleeve 130 of the distal portion 101b of the housing 101, and extend beyond the distal end of the sleeve 130 in certain configurations (such as the deployment configuration). Housing 101 further includes a slot 106 through which an operator, such as a surgeon, using the device 100 may view an indicator 107 on the deployment mechanism 103.

Housing 101 and protrusion 131 may be made of any material that is suitable for use in medical devices. For example, housing 101 and protrusion 131 may be made of a lightweight aluminum or a biocompatible plastic material. Examples of such suitable plastic materials include polycarbonate and other polymeric resins such as DELRIN and ULTEM. In certain embodiments, housing 101 and protrusion 131 are made of a material that may be autoclaved, and thus allow for housing 101 and protrusion 131 to be re-usable. Alternatively, device 100, may be sold as a one-time-use device, and thus the material of the housing and the protrusion does not need to be a material that is autoclavable.

The proximal portion 101a of housing 101 may be made of multiple components that connect together to form the housing. FIG. 4 shows an exploded view of deployment device 100. In this figure, proximal portion 101a of housing 101, is shown having two components 101a1 and 101a2. The components are designed to screw together to form proximal portion 101a of housing 101. FIG. 5 also shows deployment mechanism 103. The housing 101 is designed such that deployment mechanism 103 fits within assembled housing 101. Housing 101 is designed such that components of deployment mechanism 103 are movable within housing 101.

FIGS. 5A to 5D show different enlarged views of the deployment mechanism 103. Deployment mechanism 103 may be made of any material that is suitable for use in medical devices. For example, deployment mechanism 103 may be made of a lightweight aluminum or a biocompatible plastic material. Examples of such suitable plastic materials include polycarbonate and other polymeric resins such as DELRIN and ULTEM. In certain embodiments, deployment mechanism 103 is made of a material that may be autoclaved, and thus allow for deployment mechanism 103 to be re-usable. Alternatively, device 100 may be sold as a one-time-use device, and thus the material of the deployment mechanism does not need to be a material that is autoclavable.

Deployment mechanism 103 includes a distal portion 109 and a proximal portion 110. The deployment mechanism 103 is configured such that distal portion 109 is movable within proximal portion 110. More particularly, distal portion 109 is capable of partially retracting to within proximal portion 110.

In this embodiment, the distal portion 109 is shown to taper to a connection with a hollow shaft 104. This embodiment is illustrated such that the connection between the hollow shaft 104 and the distal portion 109 of the deployment mechanism 103 occurs inside the housing 101. Hollow shaft 104 may be removable from the distal portion 109 of the deployment mechanism 103. Alternatively, the hollow shaft 104 may be permanently coupled to the distal portion 109 of the deployment mechanism 103.

Generally, hollow shaft 104 is configured to hold an intraocular shunt 115. An exemplary intraocular shunt 115 in shown in FIG. 7. Other exemplary intraocular shunts are shown in Yu et al. (U.S. patent application number 2008/0108933). Generally, in one embodiment, intraocular shunts are of a cylindrical shape and have an outside cylindrical wall and a hollow interior. The shunt may have an inner diameter of approximately 50 μm to approximately 250 μm, an outside diameter of approximately 190 μm to approximately 300 μm, and a length of approximately 0.5 mm to about 20 mm. Thus, hollow shaft 104 is configured to at least hold a shunt of such shape and such dimensions. However, hollow shaft 104 may be configured to hold shunts of different shapes and different dimensions than those described above, and the invention encompasses a shaft 104 that may be configured to hold any shaped or dimensioned intraocular shunt. In particular embodiments, the shaft has an inner diameter of approximately 200 μm to approximately 400 μm.

The shaft 104 may be any length. A usable length of the shaft may be anywhere from about 5 mm to about 40 mm, and is 15 mm in certain embodiments. In certain embodiments, the shaft is straight. In other embodiments, shaft 104 is of a shape other than straight, for example a shaft having a bend along its length or a shaft having an arcuate portion. Exemplary shaped shafts are shown for example in Yu et al. (U.S. patent application number 2008/0108933). In particular embodiments, the shaft includes a bend at a distal portion of the shaft. In other embodiments, a distal end of the shaft is beveled or is sharpened to a point.

The shaft 104 may hold the shunt at least partially within the hollow interior of the shaft 104. In other embodiments, the shunt is held completely within the hollow interior of the shaft 104. Alternatively, the hollow shaft may hold the shunt on an outer surface of the shaft 104. In particular embodiments, the shunt is held within the hollow interior of the shaft 104. In certain embodiments, the hollow shaft is a needle having a hollow interior. Needles that are configured to hold an intraocular shunt are commercially available from Terumo Medical Corp. (Elkington, Md.).

A proximal portion of the deployment mechanism 103 includes optional grooves 116 to allow for easier gripping by an operator for easier rotation of the deployment mechanism, which will be discussed in more detail below. The proximal portion 110 of the deployment mechanism also includes at least one indicator that provides feedback to an operator as to the state of the deployment mechanism. The indicator may be any type of indicator known in the art, for example a visual indicator, an audio indicator, or a tactile indicator. FIG. 5 shows a deployment mechanism having two indicators, a ready indicator 111 and a deployed indicator 119. Ready indicator 111 provides feedback to an operator that the deployment mechanism is in a configuration for deployment of an intraocular shunt from the deployment device 100. The indicator 111 is shown in this embodiment as a green oval having a triangle within the oval. Deployed indicator 119 provides feedback to the operator that the deployment mechanism has been fully engaged and has deployed the shunt from the deployment device 100. The deployed indicator 119 is shown in this embodiment as a yellow oval having a black square within the oval. The indicators are located on the deployment mechanism such that when assembled, the indicators 111 and 119 may be seen through slot 106 in housing 101.

The proximal portion 110 includes a stationary portion 110b and a rotating portion 110a. The proximal portion 110 includes a channel 112 that runs part of the length of stationary portion 110b and the entire length of rotating portion 110a. The channel 112 is configured to interact with a protrusion 117 on an interior portion of housing component 101a (FIGS. 6A and 6B). During assembly, the protrusion 117 on housing component 101al is aligned with channel 112 on the stationary portion 110b and rotating portion 110a of the deployment mechanism 103. The proximal portion 110 of deployment mechanism 103 is slid within housing component 101al until the protrusion 117 sits within stationary portion 110b (FIG. 6C). Assembled, the protrusion 117 interacts with the stationary portion 110b of the deployment mechanism 103 and prevents rotation of stationary portion 110b. In this configuration, rotating portion 110a is free to rotate within housing component 101al.

Referring back to FIG. 5, the rotating portion 110a of proximal portion 110 of deployment mechanism 103 also includes channels 113a, 113b, and 113c. Channel 113a includes a first portion 113al that is straight and runs perpendicular to the length of the rotating portion 110a, and a second portion 113a2 that runs diagonally along the length of rotating portion 110a, downwardly toward a proximal end of the deployment mechanism 103. Channel 113b includes a first portion 113bl that runs diagonally along the length of the rotating portion 110a, downwardly toward a distal end of the deployment mechanism 103, and a second portion that is straight and runs perpendicular to the length of the rotating portion 110a. The point at which first portion 113al transitions to second portion 113a2 along channel 113a, is the same as the point at which first portion 113bl transitions to second portion 113b2 along channel 113b. Channel 113c is straight and runs perpendicular to the length of the rotating portion 110a. Within each of channels 113a, 113b, and 113c, sit members 114a, 114b, and 114c respectively. Members 114a, 114b, and 114c are movable within channels 113a, 113b, and 113c. Members 114a, 114b, and 114c also act as stoppers that limit movement of rotating portion 110a, which thereby limits axial movement of the shaft 104.

FIG. 8 shows a cross-sectional view of deployment mechanism 103. Member 114a is connected to the distal portion 109 of the deployment mechanism 103. Movement of member 114a results in retraction of the distal portion 109 of the deployment mechanism 103 to within the proximal portion 110 of the deployment mechanism 103. Member 114b is connected to a pusher component 118. The pusher component 118 extends through the distal portion 109 of the deployment mechanism 103 and extends into a portion of hollow shaft 104. The pusher component is involved in deployment of a shunt from the hollow shaft 104. An exemplary pusher component is a plunger. Movement of member 114b engages pusher 118 and results in pusher 118 advancing within hollow shaft 104.

Reference is now made to FIGS. 9-15, which accompany the following discussion regarding deployment of a shunt 115 from deployment device 100. FIG. 9A shows deployment device 100 in a pre-deployment or insertion configuration. In this configuration, shunt 115 is loaded within hollow shaft 104 (FIG. 9B). As shown in FIG. 9B, shunt 115 is only partially within shaft 104, such that a portion of the shunt is exposed. However, the shunt 115 does not extend beyond the end of the shaft 104. In other embodiments, the shunt 115 is completely disposed within hollow shaft 104. The shunt 115 is loaded into hollow shaft 104 such that the shunt abuts pusher component 118 within hollow shaft 104.

In the pre-deployment or insertion configuration, the distal portion 101b of the housing 101 is in an extended position, with spring 121 in a relaxed state (FIG. 9A). Additionally, in the pre-deployment configuration, the shaft 104 is fully disposed within the sleeve 130 of the distal portion 101b of the housing 101 (FIG. 9B). Pusher 118 abuts shunt 115 (FIG. 9B).

The deployment mechanism 103 is configured such that member 114a abuts a distal end of the first portion 113al of channel 113a, and member 114b abut a proximal end of the first portion 113bl of channel 113b (FIG. 9C). In this configuration, the ready indicator 111 is visible through slot 106 of the housing 101, providing feedback to an operator that the deployment mechanism is in a configuration for deployment of an intraocular shunt from the deployment device 100 (FIG. 9D). In this configuration, the device 100 is ready for insertion into an eye (insertion configuration or pre-deployment configuration).

FIG. 10 shows device 100 in the insertion configuration and inserted into an eye 140. Any of a variety of methods known in the art may be used to insert devices of the invention into an eye. In certain embodiments, devices of the invention may be inserted into the eye using an ab externo approach (entering through the conjunctiva) or an ab interno approach (entering through the cornea). In particular embodiment, the approach is an ab interno approach as shown Yu et al. (U.S. Pat. No. 6,544,249 and U.S. patent application number 2008/0108933) and Prywes (U.S. Pat. No. 6,007,511), the content of each of which is incorporated by reference herein in its entirety.

FIG. 10 shows an ab interno approach for insertion of device 100 into the eye 140. In this figure, protrusion 131 at the distal end of the sleeve 130 has been advanced across the anterior chamber 141 to the sclera 142 on the opposite side of the eye 140 from which the device entered the eye 140. FIG. 10 shows protrusion 131 and sleeve 130 fitted within the anterior chamber angle 143 of the eye 140. Such insertion and placement is accomplished without the use of an optical apparatus that contacts the eye, such as a goniolens. In certain embodiments this insertion is accomplished without the use of any optical apparatus.

Insertion without the use of an optical apparatus that contacts the eye, or any optical apparatus, is possible because of various features of the device described above and reviewed here briefly. The shape of the protrusion 131 is such that it corrects for an insertion angle that is too steep or too shallow, ensuring that the sleeve 130 is fitted into the anterior chamber angle of the eye, the place for proper deployment of an intraocular shunt. Further, the shape of the protrusion provides adequate surface area at the distal end of sleeve 130 to prevent enough force from being generated at the distal end of sleeve 130 that would result in sleeve 130 entering an improper portion of the sclera 142 (if the insertion angle is too shallow) or entering an improper portion of the iris 144 (if the insertion angle is too steep). Additionally, since the shaft 104 is fully disposed within the sleeve 130, it cannot pierce tissue of the eye until it is extended from the sleeve 130. Thus, if the insertion angle is too shallow or too steep, the protrusion 131 can cause movement and repositioning of the sleeve 130 so that the sleeve 130 is properly positioned to fit in the anterior chamber angle of the eye for proper deployment of the shunt. Due to these features of device 100, devices of the invention provide for deploying intraocular shunts without use of an optical apparatus that contacts the eye, preferably without use of any optical apparatus.

Once the device has been inserted into the eye and the protrusion 131 and the sleeve 130 are fitted within the anterior chamber angle of the eye, the hollow shaft 104 may be extended from within the sleeve 130. Referring now to FIG. 11 which shows extension of the shaft 104 from within the sleeve 130, which is accomplished by partial retraction of distal portion 101b of housing 101 to within proximal portion 101a of housing 101.

Retraction of the distal portion 101b of housing 101 to within proximal portion 101a of housing 101 is accomplished by an operator continuing to apply force to advance device 100 after the protrusion 131 and the sleeve 130 are fitted within the anterior chamber angle of the eye. The surface area of protrusion 131 prevents the application of the additional force by the operator from advancing sleeve 130 into the sclera 134. Rather, the additional force applied by the operator results in engagement of spring mechanism 120 and compression of spring 121 within spring mechanism 120. Compression of spring 120 results in retraction of distal portion 101b of housing 101 to within proximal portion 101a of housing 101. The amount of retraction of distal portion 101b of housing 101 to within proximal portion 101a of housing 101 is limited by member 122 that acts as a stopper and limits axial retraction of distal portion 101b within proximal portion 101a.

Retraction of distal portion 101b of housing 101 to within proximal portion 101a of housing 101 results in extension of hollow shaft 104, which now extends beyond the distal end of sleeve 130 and advances through the sclera 142 to an area of lower pressure than the anterior chamber. Exemplary areas of lower pressure include Schlemm's canal, the subconjunctival space, the episcleral vein, the suprachoroidal space, or the intra-Tenon's space.

In this figure, a distal end of the shaft is shown to be located within the intra-Tenon's space. Within an eye, there is a membrane known as the conjunctiva, and the region below the conjunctiva is known as the subconjunctival space. Within the subconjunctival space is a membrane known as Tenon's capsule. Below Tenon's capsule there are Tenon's adhesions that connect the Tenon's capsule to the sclera. The space between Tenon's capsule and the sclera where the Tenon's adhesions connect the Tenon's capsule to the sclera is known as the intra-Tenon's space. This figure is exemplary and depicts only one embodiment for a location of lower pressure. It will be appreciated that devices of the invention may deploy shunts to various different locations of the eye and are not limited to deploying shunts to the intra-Tenon's space is shown by way of example in this figure. In this configuration, the shunt 115 is still completely disposed within the shaft 104.

The distal end of shaft 104 may be beveled to assist in piercing the sclera and advancing the distal end of the shaft 104 through the sclera. In this figure, the distal end of the shaft 104 is shown to have a double bevel (See also FIG. 9B). The double bevel provides an angle at the distal end of the shaft 104 such that upon entry of the shaft into intra-Tenon's space, the distal end of shaft 104 will by parallel with Tenon's capsule and will thus not pierce Tenon's capsule and enter the subconjunctival space. This ensures proper deployment of the shunt such that a distal end of the shunt 115 is deployed within the intra-Tenon's space, rather than deployment of the distal end of the shunt 115 within the subconjunctival space. Changing the angle of the bevel allows for placement of shunt 115 within other areas of lower pressure than the anterior chamber, such as the subconjunctival space. It will be understood that FIG. 12 is merely one embodiment of where shunt 115 may be placed within the eye, and that devices of the invention are not limited to placing shunts within intra-Tenon's space and may be used to place shunts into many other areas of the eye, such as Schlemm's canal, the subconjunctival space, the episcleral vein, or the suprachoroidal space.

Reference is now made to FIGS. 12A to 12C. After extension of hollow shaft 104 from sleeve 130, the shunt 115 may be deployed from the device 100. The deployment mechanism 103 is a two-stage system. The first stage is engagement of the pusher component 118 and the second stage is retraction of the distal portion 109 of deployment mechanism 103 to within the proximal portion 110 of the deployment mechanism 103. Rotation of the rotating portion 110a of the proximal portion 110 of the deployment mechanism 103 sequentially engages the pusher component and then the retraction component.

In the first stage of shunt deployment, the pusher component is engaged and the pusher partially deploys the shunt from the deployment device. During the first stage, rotating portion 110a of the proximal portion 110 of the deployment mechanism 103 is rotated, resulting in movement of members 114a and 114b along first portions 113al and 113bl in channels 113a and 113b. Since the first portion 113al of channel 113a is straight and runs perpendicular to the length of the rotating portion 110a, rotation of rotating portion 110a does not cause axial movement of member 114a. Without axial movement of member 114a, there is no retraction of the distal portion 109 to within the proximal portion 110 of the deployment mechanism 103. Since the first portion 113bl of channel 113b runs diagonally along the length of the rotating portion 110a, upwardly toward a distal end of the deployment mechanism 103, rotation of rotating portion 110a causes axial movement of member 114b toward a distal end of the device. Axial movement of member 114b toward a distal end of the device results in forward advancement of the pusher component 118 within the hollow shaft 104. Such movement of pusher component 118 results in partially deployment of the shunt 115 from the shaft 104.

FIGS. 12A to 12C show schematics of the deployment mechanism at the end of the first stage of deployment of the shunt from the deployment device. As is shown FIG. 12A, members 114a and 114b have finished traversing along first portions 113al and 113b1 of channels 113a and 113b. Additionally, pusher component 118 has advanced within hollow shaft 104 (FIG. 12B), and shunt 115 has been partially deployed from the hollow shaft 104 (FIG. 12C). As is shown in FIG. 12C, a portion of the shunt 115 extends beyond an end of the shaft 104.

FIG. 13 shows device 100 at the end of the first stage of deployment of the shunt 115 from device 100 and into the eye 140. This figure shows that the distal portion 101b of the housing 101 remains retracted within the proximal portion 101a of the housing 101, and that the shaft 104 remains extended from the sleeve 130. As is shown in this figure, pusher 118 has been engaged and has partially deployed shunt 115 from shaft 104. As is shown in this figure, a portion of the shunt 115 extends beyond an end of the shaft 104 and is located in the intra-Tenon's space.

Reference is now made to FIGS. 14A to 14C. In the second stage of shunt deployment, the retraction component of deployment mechanism is engaged and the distal portion of the deployment mechanism is retracted to within the proximal portion of the deployment mechanism, thereby completing deployment of the shunt from the deployment device. During the second stage, rotating portion 110a of the proximal portion 110 of the deployment mechanism 103 is further rotated, resulting in movement of members 114a and 114b along second portions 113a2 and 113b2 in channels 113a and 113b. Since the second portion 113b2 of channel 113b is straight and runs perpendicular to the length of the rotating portion 110a, rotation of rotating portion 110a does not cause axial movement of member 114b. Without axial movement of member 114b, there is no further advancement of pusher 118. Since the second portion 113a2 of channel 113a runs diagonally along the length of the rotating portion 110a, downwardly toward a proximal end of the deployment mechanism 103, rotation of rotating portion 110a causes axial movement of member 114a toward a proximal end of the device. Axial movement of member 114a toward a distal proximal end of the device results in retraction of the distal portion 109 to within the proximal portion 110 of the deployment mechanism 103. Retraction of the distal portion 109, results in retraction of the hollow shaft 104. Since the shunt 115 abuts the pusher component 118, the shunt remains stationary at the hollow shaft 104 retracts from around the shunt 115. The shaft 104 retracts completely to within the sleeve 130 of the distal portion 101b of the housing 101. During both stages of the deployment process, the housing 101 remains stationary and in a fixed position.

Referring to FIG. 14A, which shows a schematic of the deployment mechanism at the end of the second stage of deployment of the shunt from the deployment device. As is shown in FIG. 14A, members 114a and 114b have finished traversing along second portions 113a2 and 113b2 of channels 113a and 113b. Additionally, distal portion 109 has retracted to within proximal portion 110, thus resulting in retraction of the hollow shaft 104 to within the housing 101.

FIG. 14B shows a schematic of the device 100 in the eye [after the second stage of deployment has been completed. FIG. 14B shows that the distal portion 101b of the housing 101 remains retracted within the proximal portion 101a of the housing 101. As is shown in these FIGS. 14B and 14C, shaft 104 has withdrawn through the sclera 134 and has fully retracted to within sleeve 130. At completion of the second stage of deployment, a distal portion of the shunt 115 has been deployed and resides in the intra-Tenon's space, a middle portion of the shunt 115 spans the sclera, and a proximal portion of shunt 115 has been deployed from shaft 104 yet still resides within sleeve 130. The proximal portion of the shunt 115 still abuts pusher 118.

Referring to FIG. 14C, in the post-deployment configuration, the deployed indicator 119 is visible through slot 106 of the housing 101, providing feedback to the operator that the deployment mechanism 103 has been fully engaged and that the deployment mechanism 103 has completed its second stage of deployment.

Referring to FIG. 15, which shows a schematic of the device 100 after completion of deployment of the shunt 115 from the device 100 and in to the eye 140. After completion of the second stage of the deployment by the deployment mechanism 103, as indicated to the operator by visualization of deployed indicator 119 through slot 106 of the housing 101, the operator may pull the device 100 from the eye 140. Backward force by the operator reengages spring mechanism 120 and results in uncoiling of spring 121. Uncoiling of spring 121 proceeds as the proximal portion 101a of housing 101 is pulled from the eye 140. Such action causes distal portion 101b to return to its extended state within proximal portion 101a of housing 101. Continued backward force by the operator continues to pull the device 100 from the eye 140. As the device 100 is continued to be pulled from the eye, the sleeve 130 is also pulled backward and the proximal portion of the shunt 115 is exposed from within the sleeve 130 and resides within the anterior chamber 141 of the eye 140. The operator continues to apply backward force until the device 100 is completely withdrawn from the eye 140.

Combinations of Embodiments

As will be appreciated by one skilled in the art, individual features of the invention may be used separately or in any combination. Particularly, it is contemplated that one or more features of the individually described above embodiments may be combined into a single shunt.

Incorporation By Reference

References and citations to other documents, such as patents, patent applications, patent publications, journals, books, papers, web contents, have been made throughout this disclosure. All such documents are hereby incorporated herein by reference in their entirety for all purposes.

Equivalents

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting on the invention described herein.

Claims

1. A device for deploying an intraocular shunt, the device comprising: a housing comprising a proximal portion and a distal portion, the distal portion comprising a sleeve;a deployment mechanism at least partially disposed within the housing; anda hollow shaft coupled inside the housing to the deployment mechanism, wherein the shaft is positioned at least partially within the sleeve and configured to hold an intraocular shunt at least partially within the shaft;wherein the distal portion is movable (i) relative to the proximal portion, the deployment mechanism, and the hollow shaft and (ii) between a distal position and a proximal position, the distal portion being biased toward the distal position; wherein the deployment mechanism comprises a pusher component and a retraction component; wherein the deployment mechanism comprises a rotatable portion, the rotatable portion being configured to sequentially engage the pusher component and then the retraction component as the rotatable distal portion rotates.

2. The device according to claim 1, further comprising an intraocular shunt that is at least partially disposed within the shaft.

3. The device according to claim 1, further comprising a member that limits axial retraction of the distal portion of the housing.

4. The device according to claim 1, wherein the distal portion further comprises a capsule.

5. The device according to claim 4, wherein the capsule is at least partially within the proximal portion when the distal portion is in the proximal position.

6. The device according to claim 1, wherein a distal end of the hollow shaft extends distally from the sleeve when the distal portion is in the proximal position.

7. The device according to claim 1, wherein the pusher component is configured to push the shunt to partially deploy the shunt from within the shaft, and the retraction component is configured to retract the shaft from around the shunt.

8. The device according to claim 1, wherein the deployment mechanism further comprises at least one member that limits axial movement of the shaft.

9. The device according to claim 1, wherein a distal end of the shaft is beveled.

10. The device according to claim 9, wherein the bevel is a double bevel.

11. The device according to claim 1, wherein the hollow shaft is a needle.

12. The device according to claim 1, wherein the device is a handheld device.

13. The device according to claim 1, further comprising an indicator mechanism formed on the housing and the deployment mechanism that provides feedback to an operator as to the state of the deployment mechanism.

14. The device according to claim 13, wherein the indicator mechanism comprises a slot, formed in the housing and extending along the deployment mechanism, for providing a visual indication of the state of the deployment mechanism.

15. The device according to claim 1, wherein the distal portion is biased toward the distal position by a spring.

16. A device for deploying an intraocular shunt, the device comprising: a housing comprising a sleeve;a deployment mechanism at least partially disposed within the housing; anda hollow shaft coupled inside the housing to the deployment mechanism, wherein the shaft is configured to hold an intraocular shunt;wherein the device comprises an insertion configuration and a deployment configuration and, when the device is in the insertion configuration, the shaft is fully disposed within the housing;wherein a distal end of the sleeve comprises a protrusion that provides resistance against advancement of the device when the protrusion contacts scleral tissue on an inside of an anterior chamber.

17. The device according to claim 16, wherein the protrusion is formed integrally with the distal end of the sleeve.

18. The device according to claim 16, wherein the protrusion is formed separately from the sleeve and connected to a distal end of the sleeve.

19. The device according to claim 16, wherein the protrusion surrounds the distal end of the sleeve.

20. The device according to claim 16, wherein the protrusion extends around only a portion of the sleeve.

21. The device according to claim 16, wherein the protrusion comprises a collar that surrounds the distal end of the sleeve.

22. A device for deploying an intraocular shunt, the device comprising: a housing comprising a sleeve;a deployment mechanism at least partially disposed within the housing; anda hollow shaft coupled inside the housing to the deployment mechanism, wherein the shaft is configured to hold an intraocular shunt;wherein the device comprises an insertion configuration and a deployment configuration and, when the device is in the insertion configuration, the shaft is fully disposed within the housing;wherein a distal end of the sleeve comprises a protrusion that comprises a flat bottom portion and an angled top portion.

23. The device according to claim 22, wherein an angle of orientation of the top portion with respect to the flat bottom portion is configured to be substantially identical to an anterior chamber angle of an eye.

24. The device according to claim 22, wherein the top portion and bottom portion are oriented at an acute angle.