Abstract: Irrigation fluid is aspirated from an eye and through an aspiration instrument by operating a vacuum pump, including moving first and second plungers between respective suction strokes and discharge strokes. Vacuum pressure at an input side of the pump is maintained at a desired vacuum pressure setting by controlling speeds and directions of the plungers, and controlling positions of input and output valves communicating with cylinders in which the plungers move. Controlling is based on the pressure setting and measured pressures in the cylinders. Vacuum pressure is maintained while transitioning from the suction stroke of the first plunger to the suction stroke of the second plunger, by synchronizing respective positions of the plungers and the valves, such that initiation of the suction stroke of the second plunger during the transitioning is delayed until a vacuum pressure in the second cylinder is equal to a vacuum pressure in the first cylinder.

Abstract: A tissue removal device includes a cannula that can aspirate tissue under a vacuum applied in the cannula, and a hermetically sealed fluid regulator in fluid communication with the cannula that generates vacuum pulses according to a controllable pulse rate and flow rate. The tissue removal device may also have a vacuum conduit having two or more conduit sections where the inner diameter of an upstream conduit section is smaller than the inner diameter of a succeeding conduit section. A device is also provided for applying an elastic membrane to an open end of the cannula to allow a user to remove any remaining cortical material after cataract material has first been removed from the eye by vacuum pressure applied in the cannula.

Abstract: Irrigation fluid is aspirated from an eye and through an aspiration instrument by operating a vacuum pump, including moving first and second plungers between respective suction strokes and discharge strokes. Vacuum pressure at an input side of the pump is maintained at a desired vacuum pressure setting by controlling speeds and directions of the plungers, and controlling positions of input and output valves communicating with cylinders in which the plungers move. Controlling is based on the pressure setting and measured pressures in the cylinders. Vacuum pressure is maintained while transitioning from the suction stroke of the first plunger to the suction stroke of the second plunger, by synchronizing respective positions of the plungers and the valves, such that initiation of the suction stroke of the second plunger during the transitioning is delayed until a vacuum pressure in the second cylinder is equal to a vacuum pressure in the first cylinder.

Abstract: A tissue removal device includes a cannula that can aspirate tissue, and a thermal element located at a tip of the cannula that can apply localized heat to the tissue to be aspirated. The tissue removal device may also include a device for applying a vacuum in the cannula, which may be configured for applying vacuum pulses according to a controlled pulse rate and vacuum level. The tissue removal device may also include a device for applying the heat at the tip according to a controllable pulse rate and power level.

Abstract: An ophthalmic cutter system that includes a cutter adapted to cut tissue such as a cataract lens and an irrigation handpiece adapted to hold the lens. The irrigation handpiece may be coupled to an irrigation system that introduces an irrigation fluid to the surgical site through the handpiece. The cutter may be coupled to an aspiration system that provides vacuum pulses to the surgical site. The vacuum pulses may pull tissue into a wire located at a distal end of a cutter cannula. The pulses may break and emulsify the tissue which is then aspirated through the cannula by the aspiration system. The wire may be connected to a controller that provides a current which is transformed into heat. The heat may assist in emulsifying the tissue.