Ocular implants deployed in schlemm's canal of the eye
View Patent ↗An ocular implant is provided that is adapted to reside at least partially in a portion of Schlemm's canal of an eye. The implant includes an implant body having plurality of filars extending along a longitudinal axis of the implant. The implant is configured to move between a radially collapsed state and a radially expanded state. In some embodiments, the implant is configured to assume the radially expanded state when no external forces are acting thereon. Methods of delivering and using the ocular implant are also provided.
1. An ocular implant, comprising:
an implant body sized and configured to be inserted into Schlemm's canal of an eye, the implant body comprising a plurality of filars, each filar having a proximal end, a distal end and an intermediate portion extending between the proximal end and the distal end, the distal ends of the filars being fixed to each other and the proximal ends of the filars being fixed to each other; and
sacrificial material constraining at least a portion of the implant body in a radially collapsed state;
the ocular implant being configured to move between the radially collapsed state and a radially expanded state, wherein the ocular implant is configured to assume the radially expanded state when the sacrificial material erodes or dissolves.
2. The ocular implant of claim 1 , wherein constraining forces are applied to the intermediate portions of the filars by the sacrificial material that adheres the individual filars together in a matrix which restricts motion between the individual filars so that expansion of the ocular implant is prohibited.
3. The ocular implant of claim 1 , wherein:
the ocular implant has a first pushability when the ocular implant is in the radially expanded state;
the ocular implant has a second pushability when the ocular implant is in the radially collapsed state; and
the second pushability is greater than the first pushability so as to facilitate advancement of the ocular implant into Schlemm's canal.
4. The ocular implant of claim 1 , wherein:
the ocular implant has a first lateral dimension when the ocular implant is in the radially expanded state;
the ocular implant has a second lateral dimension when the ocular implant is in the radially collapsed state; and
the second lateral dimension is smaller than the first lateral dimension so as to facilitate advancement of the ocular implant into Schlemm's canal.
5. The ocular implant of claim 1 , wherein a volume defined by the ocular implant has a circular cross-section.
6. The ocular implant of claim 1 , a volume defined by the ocular implant has a non-circular cross-section.
7. The ocular implant of claim 1 , a volume defined by the ocular implant has a generally ovoid or elliptical cross-section.
8. The ocular implant of claim 1 , wherein the proximal ends of the filars are fixed to a proximal hub and the distal ends of the filars are fixed to a distal hub.
9. The ocular implant of claim 8 , wherein each hub comprises a weld bead formed of material from the filars.
10. The ocular implant of claim 8 , wherein each filar follows a path that curves through three dimensional space as the filar extends distally between the proximal hub and the distal hub.
11. The ocular implant of claim 10 , wherein the path followed by each filar substantially conforms to the shape of a helix.
12. The ocular implant of claim 1 , wherein a proximal portion of the ocular implant is not fixed in the radially collapsed state so as to be free to expand into contact with Schlemm's canal to prevent migration of the ocular implant while the sacrificial material is dissolving.