Abstract
A surgical technique and device wherein an indwelling tube is placed in the eye of a patient having glaucoma. The tube diverts aqueous humor from the anterior chamber to the suprachoroidal space from which it is removed by blood flowing in the choroidal and uveal tissues. This decreases the intraocular pressure.
Claims
1. A method of treating glaucoma, comprising: providing an elongated tube comprising a first end having at least one inflow port, at least one outflow port and an internal fluid passageway communicating between the at least one inflow port and at least one outflow port; forming a flap in a sclera of an eye; folding back the flap; removing tissue from the sclera to form a scleral lake; inserting the tube into the eye so that the tube diverts fluid from the scleral lake to a suprachoroidal space of the eye.
2. A method as in claim 1, further comprising suturing the tube to the eye.
3. A method as in claim 1, further comprising cutting through a scleral bed formed when the flap in the sclera is folded back.
4. A method as in claim 1, further comprising removing a trabeculectomy specimen.
5. A method as in claim 4, wherein removing the trabeculectomy specimen creates a direct communication to the anterior chamber from the scleral lake.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when considered in conjunction with the subsequent detailed description, in which:
(2) FIG. 1 illustrates a top, three-dimensional, perspective, enlarged view of a portion of the eye, shown in partial cut-away;
(3) FIG. 2 depicts a top, three-dimensional perspective view of the second type of internal tube shunt procedure, enlarged view of the portion of the eye, shown in partial cutaway;
(4) FIG. 3 shows a top view of the portion of the eye illustrated in FIG. 1; and
(5) FIG. 4 illustrates a sectional view of the portion of the eye depicted in FIGS. 1 and 3.
(6) For purposes of brevity and clarity, like components and elements of the apparatus of this invention will bear the same designations or numbering throughout the FIGURES.
DETAILED DESCRIPTION
(7) Generally speaking, a surgical technique and apparatus is described wherein an indwelling shunt is placed in the eye of patients having glaucoma. The shunt diverts aqueous humor from the anterior chamber to the suprachoroidal space from which it is removed by the blood flowing in the choroidal and uveal tissues. This decreases the intra-ocular pressure. The indwelling shunt maintains the area of exposure of aqueous humor with the uvea by physically preventing scarring of the surrounding tissues. The method utilizes the 25 mm Hg driving force of the protein colloidal osmotic pressure of the blood to drive aqueous humor into the blood.
(8) In FIGS. 1 through 4, a portion of an eye is shown being surgically prepared with a hollow tube (indwelling shunt) 1 for the treatment of glaucoma. The hollow tube 1 has an interior open space 2 in which fluid (not shown) is transferred. The tube 1 diverts aqueous humor from the scleral lake 8 (FIG. 4) to the suprachoroidal space 12, as best observed with reference to FIGS. 1 and 3. This shunting of the aqueous humor decreases the intra-ocular pressure. The indwelling shunt 1 maintains the area of exposure of aqueous humor with the uvea by physically preventing scarring of the surrounding tissues. The method utilizes the 25 mm Hg driving force of the protein colloidal osmotic pressure of the blood of the uveal blood vessels 14 to maximize the flow (Yablonski, ibid.).
(9) The method comprises the initial step of folding back the scleral flap 4 of the eye (FIG. 1). A small cavity, the deep scleral lake 8, is generated by the removal of tissue in the sclera 7. The suprachoroidal space 12, a normally occurring potential space, is entered by cutting directly, or at a slanted angle through the scleral bed 9. The shunt 1, which can comprise a precut tube with polished edges, is then inserted into the suprachoroidal space 12 and sutured by sutures 15 to the overlying sclera 7 therein, as best seen in FIGS. 1 and 2. The precut tube 1 can also contain sutures fabricated in place for ease of deployment.
(10) After suturing the tube 1 in place, a trabeculectomy specimen 5 may be removed, thus creating a direct communication to the anterior chamber 21 (best seen in FIG. 4). A peripheral iridectomy 6 may be created in the iris 11. The scleral flap 4 is then replaced, resting on the deep scleral shelf 3 where it is tightly sutured to the adjacent sclera 7. The shunt 1 can be fabricated from silicone or other biocompatible materials. It can be seen, therefore, that this technique does not create a permanent cyclodialysis cleft and does not disinsert the ciliary body from the scleral spur.
(11) Referring to FIG. 1, the internal tube shunt 1 of the present invention is inserted and sutured between the suprachoroidal space 12 and the deep scleral lake 8 generated by the surgical forming of a scleral flap 4, and a deep sclerectomy starting 4.5 mm from the limbus and extending into the peripheral cornea 10. Since the deep sclerectomy is about 1 mm smaller than the dimensions of the scleral flap 4, a deep scleral ledge 3 approximately 0.5 mm in width is created on the lateral and posterior aspect of the deep scleral lake 8.
(12) Referring now to FIG. 2, the shunt 1 of the present invention is illustrated passing from the anterior chamber 21 through the adjacent sclera 7, through a posterior deep scleral lake 8, and into the posterior suprachoroidal space 12 where it is sutured to the overlying sclera 7. The deep scleral lake 8 is generated by forming a scleral flap 4 and deep sclerectomy similar to that of FIG. 1 but with an anterior end 3 mm posterior to the cornea 10.
(13) Referring now to FIG. 3, the shunt 1 of the present invention is inserted and laterally sutured into the suprachoroidal space 12 on each side of the deep scleral lake 8 generated by forming a scleral flap 4 and a deep sclerectomy, with the scleral flap 4 sutured back into place over the ends of the tube shunts 1. Also shown are the peripheral iridectomy 6 and the trabeculectomy site 5.
(14) Referring to FIG. 4, the shunt of this invention is seen in the deep scleral lake 8 between the overlying scleral flap 4 and the underlying scleral bed 9. Also shown are the trabeculectomy site 5 and the peripheral iridectomy 6.
(15) FIGS. 1, 3, and 4 show one possible incorporation of the invention where aqueous humor gains access to the shunt 1 via a trabeculectomy 5 between the anterior chamber 21 and the deep scleral lake 8 where one end of the tube 1 lies. From the deep scleral lake 8, aqueous humor is shunted via the tube 1 to the suprachoroidal space 12.
(16) FIG. 2 shows another possible incorporation of the invention in which aqueous humor is shunted directly by a tube 1 that passes from the anterior chamber 21 through the sclera 7 between the anterior chamber 21 and the deep sclerectomy space, and into the suprachoroidal space 12 at the posterior aspect of the deep sclerectomy where it is sutured to the overlying sclera 7.
(17) In this version, the deep sclerectomy is smaller than the deep scleral lake 8 shown in FIGS. 1 and 4. Unlike the version in FIGS. 1 and 4 where the deep scleral lake 8 serves as the pool of aqueous humor which flows into the tube 1, in the version of FIG. 2, the deep sclerectomy serves only to allow the surgeon access for insertion of the tube 1 into the anterior chamber 21, anteriorly, and the suprachoroidal space 12, posteriorly. After the tube 1 is in place, the scleral flap 4 is sutured to the adjacent sclera 7 and no permanent deep scleral lake 8 need persist.
(18) Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the examples chosen for purposes of disclosure and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention.
(19) Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.
