Abstract: A system for blood pressure measurement ascertains blood pressure indirectly by the oscillometric method at the user's index finger. Finger measurement allows the system to be smaller and easier to use than systems using conventional upper arm measurement. By using the oscillometric technique, the system according to the invention needs no microphone and so avoids the problems associated with microphone positioning. The system employs a rigid finger cuff with an inflatable inner bladder. The system extracts pulse signals transmitted via air pressure while simultaneously providing accurate pressure control.

Abstract: Single-turn loop-gap solenoidal resonators for establishing RF fields (B.sub.1) transverse to the static B.sub.0 field of a magnetic resonance imaging system. Tubular forms of dielectric (plastic) material have conductive foil bands attached to their outside walls with one or more gaps between the ends of the bands and provide solenoidal signal-turn coils. A circuit resonant at radio frequencies is defined by the inductance of the solenoidal coils formed by the bands and the capacitance across the gap. The resistors and/or capacitors spaced along the axis of the tubular bodies tune the circuit and provide RF magnetic field homogeneity within the structure. Holes in the sides of the forms through the bands provide for the entrance of the analytical sample of body mass of a subject (the head, shoulder, hand, foot, knee or elbow).

Abstract: A sensor for measuring the oxygen availability of blood flow within the skull is described. In a first embodiment the sensor comprises a photodetector and a pair of light emitting diodes surface mounted near the end of a length of flexible printed wiring. The sensor is sealed by a coating of rubber or polymeric material which has an optical window over the photodetector and light emitting diodes. The sensor is inserted through a burr hole drilled in the skull and slides between the skull and the dura of the drain. The light emitting diodes are pulsed to illuminate blood flow in the brain beneath the dura with light, and light reflected by the blood is received by the photodetector and converted to electrical signals. The signals are processed by a pulse oximeter to provide an indication of blood availability. In a second embodiment the photodetector and light emitting diodes are mounted at the end of a core of compressible foam extending from the end of a hollow bone screw.

Abstract: A method and apparatus for use with medical electrode systems that sense the integrity of lead connections and patient transthoracic impedance is provided. In an ECG electrode application, a carrier circuit (12) produces two carrier signals (S.sub.C1 and S.sub.C2) that are out of phase with each other. The S.sub.C1 signal is applied to an RA lead through a terminating impedance (Z1). The S.sub.C2 signal is applied to LA, LL and V leads through terminating impedances (Z2, Z3, and Z4). Each of the S.sub.C1 and S.sub.C2 carrier signals comprises a lead impedance frequency component (S.sub.LI) and an impedance respiration frequency component (S.sub.IR). First stage amplifiers (A1, A2, and A3) located in an ECG preamplifier (13) amplify the difference between a lead voltage on the RA lead (V.sub.RA) and lead voltages on the LA, LL, and V leads (V.sub.LA, V.sub.LL and V.sub.V). High pass filters (F1, F2 and F3) remove patient ECG signals from the outputs of A1, A2 and A3 to produce first stage output voltages (V.

Abstract: A method for rendering a gallbladder dysfunctional without surgical removal comprises the steps of infusing the gallbladder with methyl-tert-butyl ether (MTBE), then, while the gallbladder is so infused, irradiating the gallbladder with an ultrasound beam in such an ultrasound delivery format as not to elevate the average temperature of the gallbladder more than five degrees Centigrade over the period of treatment, and then removing the MTBE from the gallbladder.

Abstract: The present invention pertains to a fiducial implant for the human body that is detectable by an imaging system. The invention is comprised of a first portion and a second portion. The first portion is configured to be detected by an imaging system when placed beneath the skin. The second portion is configured for fixed attachment to a bone beneath the skin without penetrating entirely through the bone and without fracturing the bone. The first portion is of detectable size and comprised of a material for detection by an imaging system, and sufficiently small to avoid the distortion of the skin when placed at an interface between the skin and the bone. The first portion also has at least a portion which is spherical and defines a surface for cooperating with a tool for securing the second portion to the bone. Additionally, the placement into a fiducial implants, where n.gtoreq.

Abstract: A medical NMR scanner adapted to be supported on the floor of a building or other structure by vibration limiting supports is disclosed. The scanner includes a frame defining a patient-receiving space adapted to receive a human body. It also includes a pair of opposed polar regions aligned on a polar axis. The polar regions are disposed on opposite sides of the patient-receiving space. Structure is provided in each of the polar regions for producing a magnetic field within the patient-receiving space. Attenuators, positioned intermediate the frame and the building floor, are provided for attenuating transmission of vibrations from the floor to the magnetic field producing structure in order to reduce scanner image degradation.

Abstract: The phantom kidney stone system for use with a commercial lithotripsy system includes a phantom kidney stone which simulates a human kidney stone and is suspended into the field of operation of the commerical lithotripsy system. The system also includes a trigger which is connected to receive a shock wave signal from the lithotripter which is representative of a shock wave output from the lithotripter. The trigger generates a trigger signal in response to the signal from the lithotripter. A counter is connected to receive the trigger signal and counts the number of trigger signals which is representative of the number of shock waves output from the lithotripter. A detection circuit is connected to the phantom kidney stone and produces a signal proportional to the detected size of the stone at a given point in time and compares the detected size of the stone to a predetermined reference size indicative of a condition wherein the stone would be crushed.

Abstract: A support stand (B) adjustably supports either (i) a localized coil assembly or (ii) a portion of a patient within an image region of a magnetic resonance imager (A). A vertical member (42) extends upward from a base (40). A follower (44) is selectively positionable along the vertical member. In one embodiment, a universal joint (48) adjustably mounts a bracket (50) to the follower (FIG. 2). In another embodiment, the follower includes an arm (70) which receives a mounting pin (72) of the supported device. The supported device may be a surface coil (22) or an orthopedic appliance such as a knee support (80) or limb support (90). Every part of the support stand and the supported orthopedic structure, including screws and fasteners are constructed of a material which is invisible in the magnetic resonance images generated by the imager and which is a dielectric to avoid patient shock from induced currents.

Abstract: Apparatus for spatial location and destruction of an object inside a patient's body by means of ultrasound transmitted to the patient's body via a coupling fluid, the apparatus comprises a focusing transducer for generating the ultrasound piezoelectrically to destroy the object, at least two transmitting and receiving locating transducers for locating the object under visual observation, said at least two locating transducers being incorporated, installed or mounted in said focusing transducer and being operable to generate B-images which are displayed optionally individually and/or in combination as a spatial image on at least one monitor, there being preferably, three such locating transducers for generating the B-images.

Abstract: The invention contemplates an ultrasonic body treatment system wherein a body applicator is self-contained unit with its own radio-frequency oscillator/driver, factory-pretuned to its own transducer. A remote-control unit supplies control signals via optical coupling to the oscillator-driver of the body-applicator unit. Another optical coupling from the body-applicator unit to the remote-control unit enables fidelity of applicator performance to be monitored at the remote-control unit. A safety interlock at the body-applicator unit precludes transducer operation in the absence of adequate coupling to a patient's body. The remote-control unit can thus provide all supervisory and control functions for the body-applicator unit without any electrical interconnection between these units.

Abstract: A cardiac monitor (62, 64) monitors the cardiac cycles of a patient in an examination region (10). Each cardiac cycle includes an R-wave (40) at the beginning of the end-diastole. A conditioning pulse trigger (74) enables a preconditioning pulse control (34) to generate a conditioning pulse (42) at a time selected in accordance with the R-wave (40.sub.n-1) of one cardiac cycle. More specifically, an R-wave predictor (72) predicts when the next R-wave (40.sub.n) will occur and the conditioning pulse trigger enables the application of the conditioning pulse (42.sub.n) a selected duration before the next predicted R-wave (40.sub.n). An imaging sequence trigger (78) enables an image sequence controller (24) to start an imaging sequence in an imaging window (44.sub.n) in conjunction with the R-wave (40.sub.n). Preferably, the imaging sequence starts immediately with the R-wave (40.sub.n) such that the end-diastole stage of the heart is imaged.

Abstract: A permanent magnet assembly used for creating a uniform magnetic field across a portion of an air gap has a permanent magnet grouping, including a first, principal magnet, a pole piece contacting said principal magnet,and a set of auxiliary magnets extending about the periphery of the pole piece. Two such magnet groupings are positioned within a test chamber, separated by spacers, with the magnet groupings and the chamber defining an air gap across which the magnetic field extends. Apertures formed in selected panels of the test chamber enable an object to be tested to be inserted into the chamber and held within a selected portion of the magnetic field formed therewithin. The strength and uniformity of the magnetic field is adjusted by including a second set of auxiliary permanent magnets or a set of electromagnetic coils positioned within the chamber proximate the respective pole pieces.

Abstract: An air-puff tonometer, in which a puff of compressed air is blown out through a nozzle (N) toward the cornea of a subject eye (H), said compressed air being produced by energizing with an electric current a piston drive, which when thus driven compresses the air within a cylinder (5) in which the piston is mounted. The tonometer is provided with: pressure detector (11) for detecting the pressure within the cylinder (5); and current control (12, 14) for comparing a pressure signal (Vp) outputted from said pressure detector (11) with a predetermined reference signal (Vt) and for controlling the current supplied to said piston drive in such a manner that the difference between said pressure signal and said reference signal will be reduced.The air-puff tonometer so constructed will allow air within the cylinder thereof to be compressed in accordance with a predetermined pressure-time characteristic curve in spite of any change occurring in the clearance between the piston and the cylinder walls.

Abstract: To enable conventional adapter assemblies used to accurately position a removable biosensor, to be used for measurements in the interior of the skull of small children, the disclosed is a support sleeve which ensures an axial length compensation, taking into account the thinner skull bone thickness, and at the same time ensures accurate alignment of the adapter assembly and the biosensor. The support sleeve also ensures a more even distribution of axial thrust forces when the adapter assembly and the biosensor are positioned. The support sleeve comprises an inwardly extending peripheral flange defining an annular space between the flange and a tubular element slidably inserted in the sleeve. A spring element disposed in the space assures adequate anchorage in the skull bone.

Abstract: The present invention pertains to a fiducial implant for the human body that is detectable by an imaging system. The invention is comprised of a first portion and a second portion. The first portion is configured to be detected by an imaging system when place beneath the skin. The second portion is configured for fixed attachment to a bone beneath the skin without penetrating entirely through the bone and without fracturing the bone. The first portion is of dectable size and comprised of a material for detection by an imaging system, and sufficiently small to avoid the distortion of the skin when placed at an interface between the skin and the bone. The first portion also has at least a portion which is spherical defines a surfacee for cooperating with a tool for securing the second portion to the bone.

Abstract: Device construction facilitating the visibility of a device when inserted into a body being subjected to magnetic resonance imaging having a member adapted to be inserted into the body. The member carries material exhibiting a characteristic under magnetic resonance imaging which differs substantially from that of the body so that the visibility of the member under magnetic resonance imaging is substantially enhanced.Method for imaging foreign objects in a body having tissue by the use of magnetic resonance imaging and x-ray imaging. The method comprises the steps of causing the foreign object to carry at least one material causing the foreign object to exhibit a characteristic under magnetic resonance imaging which differs from the characteristic of the tissue of the body to enhance the visibility of the foreign object when positioned in the body and also to exhibit a characteristic under x-ray imaging. The foreign object is inserted into the body.

Abstract: An NMR system acquires data by performing a scan using a spin echo pulse sequence. An image is produced from the acquired data using a 2DFT reconstruction method. During the scan the echo time (TE) or the repetition time (TR) is altered as a function of phase encoding value to decrease total scan time or to improve signal-to-noise.

Abstract: This invention relates to an apparatus for disintegrating calculus having a main ultrasonic transducer for emitting a high power ultrasonic shock wave to disintegrate a kidney stone in a patient, and for emitting a weak ultrasonic shock wave, before emitting the high power ultrasonic shock wave. A sound receiver receives sounds generated by the patient's body in response to the weak ultrasonic shock wave, and converts the sounds into electrical signals. A kidney stone confirming circuit receives electrical signals from the sound receiver and determines whether the kidney stone is positioned at the focal point of the main transducer. The apparatus prevents the emission of the high power ultrasonic shock wave when the position of the kidney stone is not coincident with the focal point of the main transducer in order to prevent any harm to the patient's normal tissue.

Abstract: A therapeutical apparatus includes a measuring apparatus including a probe which generates an X-ray or ultrasonic wave in order to detect the location of a target to be treated such as calculi situated within the kidney, liver, biliary ducts. A therapeutical energy generator generates a shock wave of sufficient energy for purpose of therapy externally of the physical body and focusses it upon the target. Structure is provided for causing a displacement of the generator and the measuring apparatus around the surface of a patient. Structure is provided to activate the generator.