Abstract: Apparatus and method for locally generating hyperthermia-induced coagulation necrosis in tissue masses located deeply within the body of a subject. High energy laser radiation is introduced into the target tissue mass using an optical fiber inserted into a metallic cannula through which a suitable fluid is coaxially flowed. A combination of the fluid flow and the slow withdrawal of the cannula/fiber combination during therapy protects the optical fiber tip, thereby preserving its energy transmission characteristics. After establishment of a small fluid bolus in front of the fiber tip, fluid flow which is approximately proportionate to the laser energy employed has been found to be most effective in this regard.

Abstract: A waterproof body for an electric cautery containing cautery parts, comprising a cautery tip assembly, a first hollow half body with a button hole in its side and a receptacle in one end so as to receive the cautery tip assembly, a second hollow half body with a receptacle in on end to receive the cautery tip assembly, a waterproof flexible membrane fastened to the inside of the first half body so as to seal the button hole in a waterproof manner, and an electrical switch button fastened in the button hole of the first half body. The first and second half bodies are joined together in a waterproof manner by ultrasonic welding. The electrical switch button slides in an axial manner relative to the body.

Abstract: A pressure waveform monitor noninvasively monitors the pressure waveform in an underlying vessel such as an artery. The apparatus comprises at least one/continuous, relatively thin and narrow diaphragm mounted in a housing to be placed on the tissue overlying the vessel of interest. The diaphragm is longer than the diameter of the vessel for purposely monitoring pressure in the tissue adjacent the vessel of interest. The tonometer also comprises deformation sensor means for measuring deformation of the diaphragm both over the vessel and adjacent the vessel, and signal processing means for combining the waveform of the vessel as monitored by the part of the diaphragm over the vessel with the waveforms of adjacent tissue to accurately determine the actual pressure waveform in the vessel.

Abstract: This method for establishing the pressure-diameter relationship of an artery employs the measurement results from a non-invasive sensor (3) of the artery diameter, for instance of the humeral artery, and from a non-invasive sensor (4) of the blood pressure applied for instance to the end of a finger. The measurement locations being separated by a distance .DELTA.x, the method provides for the correction of the pressure measurements as if such measurements had been effected at the location of the diameter measurements. The method further provides a correction which takes into account the mechanical properties of the artery, defined by the parameters .alpha., .beta., .gamma., . . . and which are calculated, if necessary by successive iterations, until the pressure-diameter curve appears free from all measurement anomalies (hysteresis).

Abstract: An improved MRI sequence for suppressing a signal from a chemical shift component avoids image artifacts due to relatively large rf fields inhomogeneities as may be caused by using linearly polarized rf fields by selectively inverting the chemical shift component by means of an adiabatic fast passage rf pulse prior to spin echo excitation.

Abstract: Methodology and apparatus for the clinical evaluation of biological matter, in particular human anatomy, examined in situ and in vivo, by selective spectral light transmissivity. An optical probe introduces selected light spectra into the examination subject at a first position and resulting light intensity at a second position located some distance from the infusion point is measured; also, light reception preferably occurs at at least one other location, and the effective distances between these locations and the infusion point are determined.

Abstract: A system for determining the value of a compositional parameter of blood, including a sensor for producing a signal related to the value of the compositional parameter. A computer analyzes the signal and produces an output representing the value of the compositional parameter of blood. There is a delayed response in the system such that the signal has a time-varying waveform that varies from an initial value to an equilibrated value. The equilibrated value is predicted by detecting the occurrence of an inflection point and then computing an estimate of the equilibrated value based upon the assumption that the waveform varies exponentially from the inflection point to the equilibrated value.

Abstract: An apparatus for delivery of high intensity laser radiation of large spot size into arteries and a method for making same are disclosed. An optical radiating apparatus is formed on one end of a light-conducting optical fiber such that high intensity laser radiation leaves the optical radiation apparatus with a spot size that is expanded to a diameter significantly larger than the optical fiber diameter. The apparatus comprises a small diameter, flexible fiber which tapers to a large diameter, smooth, rounded ball tip. The taper allows the beam to expand to several millimeters in diameter and thereby ablate a large channel through an occluded artery. The smooth ball tip minimizes the chance of mechanical dissection or perforation. The fiber material is continuous such that there are no optical interfaces.

Abstract: A pulse oxymeter for measuring a blood oxygen saturation of a subject, including a first device for emitting toward a body portion of the subject a first light having a first wavelength and a second light having a second wavelength different from the first wavelength, a second device for detecting an intensity of each of the first and second lights transmitted through, or reflected by, the body portion of the subject and generating a photoelectric pulse wave signal representative of the detected intensity of each of the first and second lights, a third device for determining a blood oxygen saturation of the subject based on the pulse wave signals corresponding to the first and second lights, a probe which supports the first and second devices and is adapted to contact the body portion of the subject, and a warming device for warming the body portion of the subject.

Abstract: The present invention comprises a method and apparatus for monitoring neuromuscular blockage, and more specifically contemplates the quantitative measurement of movement of the skin of a patient overlying an electrically simulated skeletal muscle as an indicia of such blockage. The preferred embodiment of the apparatus of the present invention includes a piezoelectric film affixed over the patient's skin, the film generating an electric current in proportion to the magnitude of skin movement.

Abstract: A body electrode comprising one or more galvanically active sensors, a first layer capable of adhering to the skin on the body contact side and a non-adhesive covering second layer on the side of said sensors opposite the body contact side. The first layer comprises an electrically conducting adherent, elastic hydrophilic material. The body electrode is characterized by the fact that the first layer and the second layer have been produced by mold casting. The chief advantage of such electrodes is the fact that they may be produced by casting in a simple and cost-effective manner, thus avoiding stamping processess.

Abstract: A bipolar coagulation forceps wherein the switch at the inner side of one of its legs can be closed by an actuator at the inner side of the other leg. The switch and the actuator have cooperating centering and guide elements which engage one another to prevent any shifting of the jaws at the working ends of the legs during that stage of pivoting of the legs when the jaws already engage each other but the pivoting of the legs relative to each other must continue in order to close the switch. The latter is connected with a terminal at the rear ends of the legs by a conductor which is confined in a tube at the inner side of the leg carrying the switch. The outer side of the leg which carries the actuator has a finger-receiving flute which enhances the flexibility of the respective leg and renders it possible to pivot the legs relative to each other subsequent to engagement of the jaws with one another.

Abstract: Radiofrequency medical devices for ohmic heating of tissue of a patient include a temperature sensor carried by and in thermally conductive relationship with a thermally conductive electrode. The sensor is connected for feedback to a control circuit that modulates RF power applied to the electrode according to the signal received from the temperature sensor. The control circuit and RF power supply alternate between two operating modes. In the first mode the RF power supply applies RF power to the electrode. In the second mode the control circuit senses a signal from the temperature sensor in the absence of RF signal. The control circuit compares the signal from the temperature sensor to a set value and modulates the RF power applied to the electrode in accordance with the set value.

Abstract: A pulse wave detecting apparatus including a pulse wave sensor; a pressing device for pressing the sensor against an arterial vessel of a subject, while varying the pressing force; a first device for determining an amplitude of each of pulses of pulse wave which are detected by the sensor while the pressing force is varied; a second device for determining, based on the determined pulse amplitudes, a first range of the pressing force within which the pulse amplitudes are generally constant, the first range including a point at which a rate of change of the pulse amplitudes with respect to the pressing force is zero; a third device for determining a minimum value of each of the pulses detected by the sensor; a fourth device for determining, based on the determined pulse minimum magnitude, a second range of the pressing force within which the pulse minimum magnitudes are generally constant, the second range including a point at which a rate of change of the pulse minimum magnitudes with respect to the pressing f

Abstract: A mechanically expandable esophageal catheter has an elongated flexible body which carries at a distal end thereof one or more electrically conducting members. The conducting members are moveable laterally with respect to the body portion of the catheter by means of a mechanical structure contained therein. The degree and extent of mechanical movement can be controlled by a stylet from a proximal end of the catheter.

Abstract: A fiber-optic sensor for measuring a parameter of a test fluid, including a chemical sensor, incorporating a dye composition which displays changes in its optical properties correlated to changes in the parameter to be measured. The sensor is coupled to an apparatus including a light source, and means for measuring light received from said sensor at three different peak wavelengths. The first wavelength is chosen such that the optical characteristics of the dye with respect to that wavelength do not change significantly with changes in the parameter to be measured. The second and third wavelengths are chosen such that optical characteristics of the dye with respect to these wavelengths do change along with changes in the parameter to be measured, and also change as a function of temperature. The light received from the sensor at first, second and third wavelengths is compared to determine the temperature of the test fluid and to provide a temperature correction for the parameter to be measured.

Abstract: This is a hand switch adapter for use with two prong bipolar forceps. It utilizes a reed spring for energizing a circuit which in turn activates the main circuit.

Abstract: A device for storing and delivering a sensor through a catheter. A sensor delivery device (10, 10') includes an elongate tube (20), which is attached to a rigid housing (22,22'). A sensor (12), stored within a sterile environment comprising an interior of the sensor delivery device, has an attached signal line (16) that extends along the longitudinal axis of the delivery device and through its proximal end. The proximal end is open when the sensor is in its stored position. An eversible sheath (34) extends between the rigid housing and the signal line, sealingly separating the sterile environment (48) in which the sensor is stored from the open end of the rigid housing. To use the sensor, the signal line is moved into the rigid housing, causing the eversible sheath to turn inside out as the sensor is advanced through the catheter into its use position. The projection afforded by the eversible sheath permits the sensor to be withdrawn through the catheter and then reinsertd without introducing contamination.

Abstract: This invention is related to an improved method and apparatus for use in controlling the ultrasonic fragmentation of the body tissue. The ultrasonic apparatus includes a transducer assembly mounted in the handpiece assembly. The transducer is operable for converting electrical power to ultrasonic mechanical vibrational energy. A vibrational amplifying device is coupled to the transducer assembly and includes in series asymmetrical horn and symmetrical horn portions. Included in one of the horn portions is an operative tip.

Abstract: A wireless low-frequency medical treatment device having a sending section for sending data for low-frequency medical treatment and a pulse applying section for receiving the above data and applying a low-frequency pulse corresponding to the data on a living body, the device being characterized in that the sending section comprises a plurality of sending coils, whose axes cross each other in a space, and a sending coil driving circuit for supplying the sending coils with resonating currents having different phases, respectively, the currents indicating a signal corresponding to the data; and that the pulse applying section comprises a receiving coil for receiving the signal sent from the sending coils through electromagnetic induction.