Appts. for extn. of fragments during surgical treatment of cataract

摘要

Lens fragments are rinsed out of the eye in liq. supplied from an infusion bottle (30) to the hand-held cannula (21), and drawn through suction lines (16, 17) by a peristaltic pump (11). A junction (18) allows the extn. path to be vented from a valve (26). The vacuum is variable in steps from zero to 550 torr with a choice of six rates of increase set by a controller (32). A computer (35) adjusts the speed of the pump motor (12) by means of a regulating amplifier (44) responsive to a pressure gauge (23) and a set-point (40).