Devices, system and methods for minimally invasive glaucoma surgery
A surgical device, system and method for forming opening in the trabecular meshwork of eyes to facilitate drainage of aqueous humor and resultant lowering of intraocular pressure are provided. The device comprises a shaft and a distal member or foot on a distal end of the shaft. The distal member or foot may have a forward tip, a right edge, a left edge and a transversely concave depression, cavity or space between the right and left edges. The distal member is insertable into Schlemm's canal of an eye and thereafter advanceable through Schlemm's canal such that trabecular meshwork tissue will be cut by the right and left edges.
1. A device comprising:
a shaft;
a distal member positioned at a distal end of the shaft, said distal member comprising:
a forward end and a rearward end;
a forward tip formed at the forward end of the distal member;
a right edge and a left edge progressing rearwardly from the forward tip;
a depression, trough, cavity or open area rearward of the forward tip and between the right edge and the left edge;
a bottom that is curved upwardly and rearwardly from the forward tip to the rearward end, wherein the right and left edges incline at an angle of between about 35 degrees to 40 degrees relative to a transverse axis of the shaft;
wherein at least portions of the right and left edges are serrated; and
wherein at least portions of the right and left edges are configured to cut tissue as the tissue advances in the rearward direction over the right and left edges.
2. The device according to claim 1 wherein the right edge and left edge rotate as they progress rearward.
3. The device according to claim 2 wherein, at a first location on the forward tip, the right edge and left edge are positioned at a first height and oriented at a first orientation that is vertical or near vertical.
4. The device according to claim 3 wherein, at a second location rearward of the first location, the right edge and left edge are higher than at the first location and have a rotation to a second orientation between horizontal and vertical and further from vertical than the first orientation.
5. The device according to claim 4 wherein, at a third location rearward of the second location, the right edge and left edge are higher than at the second location and have a further rotation to a third orientation that is past horizontal and sloping downward toward the cavity.
6. The device according to claim 5 wherein, at a fourth location rearward of the third location, the right edge and left edge are higher than at the third location.
7. The device according to claim 5 wherein, in a region that includes the third location, the right and left edges are configured to cut tissue.
8. The device according to claim 7 wherein, within said region, the right and left edges have serrations.
9. The device according to claim 1 wherein the right edge and left edge increase in height as they progress rearward.
10. The device according to claim 1 wherein the right edge and left edge increase in height and rotate as they progress rearward.
11. The device according to claim 1 further comprising an aspiration lumen.
12. A system comprising the device according to claim 11 in combination with an aspiration pump connected to the aspiration lumen.
13. The system according to claim 12 wherein the aspiration pump is part of a phacoemulsification console or phacoemulsification surgical system.
14. The device according to claim 1 further comprising an irrigation lumen.
15. The device according to claim 1 further comprising an aspiration lumen and an irrigation lumen.
16. A method for using the device according to claim 1 to form an opening in trabecular meshwork tissue of an eye having a Schlemm's Canal, an anterior chamber and a trabecular meshwork, said method comprising the steps of:
inserting into the anterior chamber a distal portion of said device, said distal portion including the distal member;
advancing the distal member, the forward tip first, through the trabecular meshwork and into Schlemm's Canal; and
advancing the distal member, the forward tip first, through Schlemm's Canal such that trabecular meshwork tissue contacts and is severed by the right and left edges of the distal member.
17. The method according to claim 16 wherein the device further comprises an aspiration lumen and wherein the method further comprises aspirating tissue and/or fluid through the aspiration lumen.
18. The method according to claim 17 wherein the device further comprises an irrigation lumen and wherein the method further comprises delivering fluid into the eye through the irrigation lumen.
19. The method according to claim 18 wherein hyphema or collection of blood within the anterior chamber occurs and wherein irrigation and aspiration are used to clear blood from the anterior chamber.
20. The method according to claim 17 wherein trabecular meshwork tissue that is severed during the procedure is aspirated into the aspiration lumen.
21. The device according to claim 1 , wherein the depression, trough, cavity or open area rearward of the forward tip and between the right edge and the left edge is U-shaped.