Abstract: A method of determining the accuracy of a pressure sensor in a surgical cassette is disclosed. The method involves displacing a diaphragm of the sensor a pre-defined amount of displacement, and measuring the force exerted on the diaphragm by the displacing step. The accuracy of the pressure sensor is determined by comparing the force measured in the measuring step to a pre-defined force for the pre-defined amount of displacement.

Abstract: An improved, asynchronous method of operating a microsurgical instrument, such as a vitrectomy probe. The instrument includes a port for receiving tissue and an inner cutting member. A flow of tissue is induced into the port with a vacuum source. The port is at least partially occluded with the tissue. The occlusion is detected, and the inner cutting member is actuated to close the port and cut the tissue.

Abstract: A method of determining the accuracy of a pressure sensor in a surgical cassette is disclosed. The method involves displacing a diaphragm of the sensor a pre-defined amount of displacement, and measuring the force exerted on the diaphragm by the displacing step. The accuracy of the pressure sensor is determined by comparing the force measured in the measuring step to a pre-defined force for the pre-defined amount of displacement.

Abstract: A microsurgical system, and a method of mapping the surgical functions of the microsurgical system to a foot controller operatively coupled with the system, are disclosed. The microsurgical system includes a computer, a foot controller operatively coupled to the computer, and a touch screen display operatively coupled to the computer. The foot controller has a plurality of switches. Each of the switches is for controlling a surgical function of the microsurgical system and for actuation by a user's foot. The touch screen display has the ability to display a graphic representation of the foot controller including the plurality of switches, and to display a list of surgical functions so that the list is associated with the graphical representation of one of the plurality of switches. By touching one of the surgical functions in the list, a user can exchange the surgical functions associated with any two of the plurality of switches on the foot controller.

Abstract: A microsurgical system, and a method of mapping the surgical functions of the microsurgical system to a foot controller operatively coupled with the system, are disclosed. The microsurgical system includes a computer, a foot controller operatively coupled to the computer, and a touch screen display operatively coupled to the computer. The foot controller has a plurality of switches. Each of the switches is for controlling a surgical function of the microsurgical system and for actuation by a user's foot. The touch screen display has the ability to display a graphic representation of the foot controller including the plurality of switches, and to display a list of surgical functions so that the list is associated with the graphical representation of one of the plurality of switches. By touching one of the surgical functions in the list, a user can exchange the surgical functions associated with any two of the plurality of switches on the foot controller.

Abstract: An improved, asynchronous method of operating a microsurgical instrument, such as a vitrectomy probe, is disclosed. The instrument includes a port for receiving tissue and an inner cutting member. A flow of tissue is induced into the port with a vacuum source. The port is at least partially occluded with the tissue. The occlusion is detected, and the inner cutting member is actuated to close the port and cut the tissue.

Abstract: Blood from a patient is treated extracorporeally by any selected one of a plurality of predetermined treatments. Each of the treatments involves the flow of blood from the patient into a primary chamber of a filtration unit, past a semipermeable membrane located in the filtration unit which separates the primary chamber from a secondary chamber of the filtration unit, out the filtration unit and back to the patient. A replacement fluid is selectively and controllably added to the blood, as required for the selected treatment. A secondary fluid is controllably and selectively introduced into the secondary chamber of the filtration unit for controllably collecting material passing across the semipermeable membrane from the blood or for supplying material to pass across the semipermeable membrane into the blood as required for the selected treatment. Materials are removed from the secondary chamber and collected in accordance with the selected treatment.

Abstract: Blood from a patient is treated extracorporeally by any selected one of a plurality of predetermined treatments. Each of the treatments involves the flow of blood from the patient into a primary chamber of a filtration unit, past a semipermeable membrane located in the filtration unit which separates the primary chamber from a secondary chamber of the filtration unit, out the filtration unit and back to the patient. A replacement fluid is selectively and controllably added to the blood, as required for the selected treatment. A secondary fluid is controllably and selectively introduced into the secondary chamber of the filtration unit for controllably collecting material passing across the semipermeable membrane from the blood or for supplying material to pass across the semipermeable membrane into the blood as required for the selected treatment. Materials are removed from the secondary chamber and collected in accordance with the selected treatment.

Abstract: An organ support system and method adapted for use with a patient and designed to modify the blood from the patient includes a control system, a venous line coupled to an output of a patient, an arterial line coupled to an input of the patient, and a cell line inserted into a hollow fiber cartridge to form an organ assist device. Blood is passed through the organ assist device. A small flow is extracted from the extracapillary space to check the integrity of the organ assist device. With this closed loop arrangement, a proper fluid balance can be maintained for the patient without requiring any dialysate, and leaks from the cell line to the patient can be immediately detected and prevented from reaching the patient.

Abstract: Dialysis unit with vacuum removal therethrough of priming saline and selective circulation therethrough of dialysate and other fluids. The dialyzer unit includes a drain configured to sealingly cooperate with a tubing set having a cap with a central conduit portion and sealing fins for cooperating with the drain, and a venturi in a main effluent passage in fluid communication with the drain.

Abstract: Apparatus for collecting blood components including a supply line that is connected to a blood line and has a filter on it to permit passage of supply solution (e.g., anticoagulant or saline prime) and blocks passage of bacteria.

Abstract: A liquid conductivity sensor which features simply and inexpensively driving the excitation transformer of a two-transformer/fluid-loop remote conductivity sensor with a square wave excitation signal provided by a digital timer and a flip-flop. Also disclosed is using an electrodeless conductivity sensor to sense conductivity of dialysate.

Abstract: A tubing injection site guard comprising a compressible, penetrable sleeve for surrounding a continuous tube and a rigid casing enclosing the sleeve. The casing comprises two opposing longitudinal sections longitudinally hinged, with a needle access port in one section to allow insertion of a needle through the sleeve and into the tube. The sections are capable of being locked together to radially compress the sleeve over its entire length and thereby seal needle holes. An adjustable locking means is provided to lock the sections together and to allow adjustment of the radial compression. The site guard also protects the operator from injury while inserting the needle by enclosing the entire injection site except at the needle access port.

Abstract: Making temperature measurements of blood inside a disposable, sterilized medical device by providing receptacles in the walls of the device for receiving temperature-sensitive probes, the receptacles including a tubular heat-conductive member, extending through a wall of the device and being sealed to the wall, and a cylindrical body having protuberances extending radially for cooperating with slots in a temperature-sensitive probe.

Abstract: Diffusing gas into and out of a liquid at a uniform rate by distributing a foam consisting of bubbles with liquid walls surrounding the gas through elongated passages defined by a corrugated surface adjacent to a smooth surface, while simultaneously providing for indirect heat - exchange of the blood foam while the foam is within the elongated passages.

Abstract: A blood oxygenator with an oxygen filter in the oxygen inlet chamber, featuring in a particular aspect elevating the filter above the diffuser plug of the oxygenator.

Abstract: A fluid valve with a core received in the bore of a valve body, the bore being positioned in a separate inner body spaced radially inward from and connected by support means to the main valve body so as to hasten cooling of the bore during manufacturing and thereby improve sealing of the core by reducing dimensional variations in the bore.

Abstract: Monitoring the level of both opaque and clear liquids in a reservoir without contacting the liquids by providing first and second reservoir wall portions that define a region through which a light beam is passed from a light source to a light sensor so that opaque liquid extinguishes the light beam and so that the wall portions cooperate with the clear liquid to refract the light beam away from the sensor. A monitoring line segment, defined as the portion of a hypothetically unrefracted and unreflected light beam between the first and second reservoir wall portions, is a small fraction of the largest interior linear dimension of the reservoir in a plane containing the monitoring line segment and a line normal to the first reservoir wall portion.