Abstract: A pulsed fluid jet surgical instrument includes a cannula extending from a handpiece, the cannula emitting a pulsed fluid jet for cutting and emulsification purposes, and also providing suction for aspiration and evacuation of the fluid and tissue. A pressure intensifier piston arrangement receives fluid at relatively low pressure, and operates reciprocally and reiteratively to pump the fluid through the jet needle in a series of high pressure pulses, each having a nearly rectangular pressure waveform. The pressure intensifier piston is T-shaped, including a broad end which divides a drive bore into a driving chamber and a retracting chamber. A bistable valve is connected to admit high pressure gas into the actuating chamber, driving the piston to translate. The narrow end of the piston is disposed in a fluid pumping chamber connected to a supply of fluid.

Abstract: A method and apparatus for the excision and removal of tissue, such as the lens of the eye includes a pencil-like handpiece having a cannula probe extending from the distal end thereof. The probe includes an inner jet tube to direct a high pressure jet of fluid toward a tissue target, and an outer concentric aspiration tube to aspirate and remove fluid and tissue. The jet tube is recessed proximally within the concentric aspiration tube, and the aspiration tube has an end area significantly larger than the end area of the jet tube. These factors cooperate so that the negative pressure exerted by the aspiration tube creates a suction force that offsets and exceeds the force of the fluid jet. The jet tube is connected to a fluid pressure system including a positive displacement pump, a pressure regulator, safety release, control valve, and a pulse former.

Abstract: Apparatus for supporting and guiding the movement of a high speed liquid jet for ophthalmic incisions includes a fixture for removably securing the device with respect to the apex of the cornea. The corneal apex extends through an opening in the fixture, and a concentric suction ring secures the fixture to the eyeball. A proximal portion of the fixture is provided with an internal cutout to permit resilient horizontal flexure of the proximal portion. A first linear actuator is arranged to drive the first flexible bracket to translate horizontally in precisely controlled motion. Joined orthogonally to the fixture is a second flexible bracket, having an internal cutout that permits resilient vertical flexure. One end of the second flexible bracket is secured rigidly to the fixture, and a micrometer actuator is joined to the movable end of the second flexible bracket to position it vertically in precisely controlled spacing.

Abstract: A fluid jet surgical cutting instrument having a pressure generating mechanism disposed within the housing of the instrument. The pressure generating mechanism includes a piston member which is reciprocatingly movable within the housing by alternately supplying gas to the distal end of the piston and the proximal end of the piston. The gas is supplied in an alternating manner through the provision of a novel actuator mechanism which includes a plurality of passageways which permits charging of gas to the pressure amplifying mechanism as well as venting of gas from the pressure amplifying mechanism to permit reciprocating movement.

Abstract: A pulsed fluid jet surgical instrument includes a cannula extending from a handpiece, the cannula emitting a pulsed fluid jet for cutting and emulsification purposes, and also providing suction for aspiration and evacuation of the fluid and tissue. A pressure intensifier piston arrangement receives fluid at relatively low pressure, and operates reciprocally and reiteratively to pump the fluid through the jet needle in a series of high pressure pulses, each having a nearly rectangular pressure waveform. The pressure intensifier piston is T-shaped, including a broad end which divides a drive bore into a driving chamber and a retracting chamber. A bistable valve is connected to admit pressure gas into the actuating chamber, driving the piston to translate. The narrow end of the piston is disposed in a fluid pumping chamber connected to a supply of fluid.