Abstract: The invention discloses a medical instrument, comprising: a handle, a blade portion having a sharpened edge for cutting a lens capsule of an eye at the periphery of a portion of said capsule to be removed during surgery, said blade portion being extendible and retractable from the handle tip portion thereby permitting insertion of said blade portion through a small incision in the eye when the blade is retracted and thereafter to correspond to a peripheral extent to said portion of the capsule to be removed during surgery, a mechanism for extending and retracting said blade portion, said mechanism located in said handle portion, and a foot pedal-controlled motor coupled to said handle for effecting cutting of capsule by sad blade portion. The invention additionally relates to a method for utilizing a medical instrument in performing cataract surgery.

Abstract: A medical instrument including (a) a handle; (b) a cautery for burning a lens capsule of an eye at the periphery of a portion of the capsule to be removed during surgery, the cautery including a retractable-extendible cautery portion being retractable into and extendible from the handle, so as to permit insertion of the cautery portion through a small incision formed in the eye when retracted and thereafter to correspond to a peripheral extent of the portion of the capsule to be removed when extended; (c) a mechanism for retracting and extending the cautery portion, the mechanism being engaged by the handle; and (d) an arrangement for connecting the cautery with an electrical apparatus for heating the cautery portion, whereby the peripheral extent of the capsule portion to be removed is searable by the cautery portion when extended and heated.