VARYING A NUMERICAL APERTURE OF A LASER DURING LENS FRAGMENTATION IN CATARACT SURGERY

摘要

Some embodiments disclosed here provide for a method fragmenting a cataractous lens of a patient's eye using an ultra-short pulsed laser. The method can include determining, within a lens of a patient's eye, a high NA zone where a cone angle of a laser beam with a high numerical aperture is not shadowed by the iris, and a low NA zone radially closer to the iris where the cone angle of the laser beam with a low numerical aperture is not shadowed by the iris. Laser lens fragmentation is accomplished by delivering the laser beam with the high numerical aperture to the high NA zone, and the laser beam with the low numerical aperture to the low NA zone. This can result in a more effective fragmentation of a nucleus of the lens without exposing the retina to radiation above safety standards.

主权项

1. A method for fragmenting a lens of a patient's eye using a surgical laser comprising:
measuring features of the patient's eye to find a total laser treatment region; determining:
a safety zone comprising a region of the patient's eye that will not receive focused laser radiation;a high NA zone, the high NA zone comprising a region where a cone angle of a laser beam with a high numerical aperture is not shadowed by an iris of the patient's eye; anda low NA zone, the low NA zone comprising a region radially closer to the iris than the high NA zone where the cone angle of the laser beam with a low numerical aperture is not shadowed by the iris; and delivering the laser beam with the high numerical aperture to the high NA zone, and delivering the laser beam with the low numerical aperture to the low NA zone, wherein the high NA zone, the low NA zone, and the safety zone occupy, in aggregate, approximately the entirety of the total laser treatment region.