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 laser cataract surgery control system comprising:
a laser source configured to emit a laser beam; a controller comprising one or more physical processors; a fragmentation module configured to use the one or more physical processors to determine a laser lens fragmentation treatment plan by determining:
a first region of a lens of a patient's eye to receive a first focus of the laser beam having a first numerical aperture; anda second region of the lens of the patient's eye to receive a second focus of the laser beam having a second numerical aperture, the second numerical aperture being lower than the first numerical aperture, and the second region being radially closer, on average, to an iris of the patient's eye than the first region; a laser control module in communication with the laser source and configured to:
control the laser source to deliver the laser beam having the first numerical aperture and a first energy to the first region of the lens; andcontrol the laser source to deliver the laser beam having the second numerical aperture and a second energy to the second region of the lens without delivering the laser beam having the first numerical aperture and the first energy to the second region of the lens, wherein the first numerical aperture and the first energy are configured to deliver a first peak laser energy to a retina of the patient's eye that is less than or equal to a safety threshold.