Ocular delivery systems and methods
Described here are systems and methods for accessing Schlemm's canal and for delivering an ocular device, tool, or fluid composition therein. The ocular devices may maintain the patency of Schlemm's canal without substantially interfering with transmural fluid flow across the canal. The fluid composition may be a viscoelastic fluid that is delivered into the canal to facilitate drainage of aqueous humor by disrupting the canal and surrounding trabeculocanalicular tissues. Some systems described here may be configured to cut or tear the trabecular meshwork with the body of an elongate member located within Schlemm's canal. Other tools for disrupting these tissues and minimally invasive methods for treating medical conditions associated with elevated intraocular pressure, including glaucoma, are also described.
1. A method for treating a condition of an eye comprising:
advancing a distal end of a device comprising an elongate member and a fluid assembly coupled to a linear gear via a linkage into an anterior chamber of the eye;
advancing the elongate member into Schlemm's canal by advancing the linear gear and the fluid assembly, wherein the linkage maintains a fixed distance between the linear gear and the fluid assembly during advancement; and
retracting the elongate member and simultaneously delivering a fluid composition through the elongate member into Schlemm's canal by retracting the linear gear without retracting the fluid assembly or the linkage.
2. The method of claim 1 further comprising tearing a trabecular meshwork of the eye.
3. The method of claim 2 , wherein the trabecular meshwork is torn by the elongate member.
4. The method of claim 3 , wherein the trabecular meshwork is torn by a body of the elongate member.
5. The method of claim 2 , wherein the elongate member is advanced a first length around Schlemm's canal, and wherein the fluid composition is delivered to the same first length around Schlemm's canal.
6. The method of claim 5 , wherein the trabecular meshwork is torn along the same first length around Schlemm's canal.
7. The method of claim 6 , wherein the trabecular meshwork is torn by the elongate member.
8. The method of claim 5 , wherein the trabecular meshwork is torn along a length other than the first length around Schlemm's canal.
9. The method of claim 2 , wherein the elongate member is advanced about 180 degrees around Schlemm's canal in a first direction.
10. The method of claim 9 further comprising:
advancing the elongate member about 180 degrees around Schlemm's canal in a second direction; and
retracting the elongate member and simultaneously delivering a fluid composition through the elongate member.
11. The method of claim 10 further comprising tearing the trabecular meshwork a second time.
12. The method of claim 10 , wherein tearing the trabecular meshwork comprises tearing the trabecular meshwork around Schlemm's canal in the first direction and tearing the trabecular meshwork around Schlemm's canal in the second direction.
13. The method of claim 12 , wherein tearing the trabecular meshwork in the first direction comprises tearing the trabecular meshwork 180 degrees around Schlemm's canal in the first direction.
14. The method of claim 13 , wherein tearing the trabecular meshwork in the second direction comprises tearing the trabecular meshwork 180 degrees around Schlemm's canal in the second direction.
15. The method of claim 10 , wherein advancing the elongate member into Schlemm's canal moves the fluid assembly distally to a first position, and wherein advancing the elongate member into Schlemm's canal in the second direction moves the fluid assembly from the first position distally to a second position.
16. The method of claim 1 , wherein between about 2 microliters and about 9 microliters of the fluid composition are delivered to Schlemm's canal.
17. The method of claim 16 , wherein about 4.5 microliters of the fluid composition are delivered to Schlemm's canal.
18. The method of claim 9 , wherein about 10 microliters of the fluid composition are delivered to Schlemm's canal.
19. The method of claim 10 , wherein about 20 microliters of the fluid composition are delivered to Schlemm's canal in total.
20. The method of claim 1 , wherein the device further comprises a housing and a lock configured to restrict movement of the fluid assembly relative to the housing prior to use, and the method further comprises disengaging the lock to allow movement of the fluid assembly relative to the housing.
21. The method of claim 1 , wherein the device further comprises a housing, and wherein the fluid assembly moves distally, but not proximally, relative to the housing.
22. The method of claim 21 , wherein the housing comprises teeth that allow the fluid assembly to move distally relative to the housing during advancement of the elongate member and that fix the fluid assembly relative to the housing during retraction of the elongate member.
23. The method of claim 1 , wherein the fluid assembly comprises a luer fitting or a one-way valve for transfer of the fluid composition into the fluid assembly.
24. The method of claim 1 , wherein retracting the elongate member and delivering the fluid composition are both actuated by rotation of a wheel.
25. A method for treating a condition of an eye comprising:
advancing a distal end of a device comprising an elongate member and a fluid assembly coupled to a linear gear via a linkage into an anterior chamber of the eye;
advancing the elongate member into Schlemm's canal in a first direction by advancing the linear gear and the fluid assembly;
retracting the elongate member and simultaneously delivering a fluid composition through the elongate member into Schlemm's canal by retracting the linear gear without retracting the fluid assembly or the linkage;
advancing the elongate member into Schlemm's canal in a second direction by advancing the linear gear and the fluid assembly a second time;
retracting the elongate member and simultaneously delivering a fluid composition through the elongate member into Schlemm's canal by retracting the linear gear without retracting the fluid assembly or the linkage a second time; and
tearing the trabecular meshwork along the first direction and the second direction,
wherein the linkage maintains a fixed distance between the linear gear and the fluid assembly during advancement.