L-shaped implant with bi-directional flow

#The present invention generally relates to improved medical devices and methods for the reduction of elevated pressure in organs of the human body. More particularly, the present invention relates to the treatment of glaucoma by trabecular bypass surgery, which is a means for using an implant or seton, such as a micro stent, shunt or the like, to bypass diseased trabecular meshwork at the level of trabecular meshwork and use/restore existing outflow pathways.

#About two percent of people in the United States have glaucoma. Glaucoma is a group of eye diseases that causes pathological changes in the optic disk and corresponding visual field loss resulting in blindness if untreated. Intraocular pressure elevation is the major etiologic factor in all glaucomas.

#In glaucomas associated with an elevation in eye pressure the source of resistance to outflow is in the trabecular meshwork. The tissue of the trabecular meshwork allows the “aqueous” to enter Schlemm's canal, which then empties into aqueous collector channels in the posterior wall of Schlemm's canal and then into aqueous veins. The aqueous or aqueous humor is a transparent liquid that fills the region between the cornea at the front of the eye and the lens. The aqueous humor is constantly secreted by the ciliary body around the lens, so there is a continuous flow of the aqueous humor from the ciliary body to the eye's front chamber. The eye's pressure is determined by a balance between the production of aqueous and its exit through the trabecular meshwork (major route) or via uveal scleral outflow (minor route). The trabecular meshwork is located between the outer rim of the iris and the internal periphery of the cornea. The portion of the trabecular meshwork adjacent to Schlemm's canal causes most of the resistance to aqueous outflow (juxtacanilicular meshwork).

#Additional objects and features of the present invention will become more apprent and the invention itself will be best understood from the following Detailed Description of Exemplary Embodiments, when read with reference to the accompanying drawings.

#FIG. 1 is a sectional view of an eye for illustration purposes.

#FIG. 2 is a close-up sectional view, showing the anatomical diagram of trabecular meshwork and the anterior chamber of the eye.

#Referring to FIGS. 1 to 7, what is shown is a method for the treatment of glaucoma by trabecular bypass surgery. In particular, a seton implant is used to bypass diseased trabecular meshwork at the level of trabecular meshwork to use or restore existing outflow pathways and methods thereof.

#For background illustration purposes, FIG. 1 shows a sectional view of an eye 10, while FIG. 2 shows a close-up view, showing the relative anatomical locations of the trabecular meshwork, the anterior chamber, and Schlemm's canal. Thick collagenous tissue known as sclera 11 covers the entire eye 10 except that portion covered by the cornea 12. The cornea 12 is a thin transparent tissue that focuses and transmits light into the eye and the pupil 14 which is the circular hole in the center of the iris 13 (colored portion of the eye). The cornea 12 merges into the sclera 11 at a juncture referred to as the limbus 15. The ciliary body 16 begins internally in the eye and extends along the interior of the sclera 11 and becomes the choroid 17. The choroid 17 is a vascular layer of the eye underlying retina 18. The optic nerve 19 transmits visual information to the brain and is sequentially destroyed by glaucoma.

#The anterior chamber 20 of the eye 10, which is bound anteriorly by the cornea 12 and posteriorly by the iris 13 and lens 26, is filled with aqueous. Aqueous is produced primarily by the ciliary body 16 and reaches the anterior chamber angle 25 formed between the iris 13 and the cornea 12 through the pupil 14. In a normal eye, the aqueous is removed through the trabecular meshwork 21. Aqueous passes through trabecular meshwork 21 into Schlemm's canal 22 and through the aqueous veins 23 which merge with blood-carrying veins and into venous circulation. Intraocular pressure of the eye 10 is maintained by the intricate balance of secretion and outflow of the aqueous in the manner described above. Glaucoma is characterized by the excessive buildup of aqueous fluid in the anterior chamber 20 which produces an increase in intraocular pressure (fluids are relatively incompressible and pressure is directed equally to all areas of the eye).