Abstract: A therapy apparatus for treatment with focused acoustic waves which has a source of focused acoustic waves, an acoustic receiver for the reception of parts of the acoustic waves reflected from a subject to be acoustically irradiated, and can be switched from a therapy mode to a locating mode. The apparatus also include circuitry for varying the oscillatory frequency of the generated acoustic waves dependent on whether the apparatus is switched to the therapy or locating mode. A method for operating such an apparatus is also disclosed.

Abstract: The integrity (density) of discrete pieces of hard tissue (bones) in a patient may be determined by either one of two methods. In a first method, an impulse of energy is introduced into the hard tissue, such as by striking the patient's hard tissue, and the induced vibration is sensed and analyzed in order to compute the damping factor thereof, the damping factor being directly related to the density thereof. With this method, a transducer is coupled to the hard tissue and its output is amplified by an amplifier before input to a computer which determines the damping factor. In a second method, a continuous energy input is provided to the hard tissue, such as by utilizing a frequency generator coupled to a power amplifier whose output drives a transducer such as a speaker or the like for inducing a continuous vibration in the hard tissue. This continuous vibration is measured with a transducer, having amplified output, and a damping factor is calculated with a computer.

Abstract: Methods for measuring the perfusion of fluid in a substance are shown to include subjecting the fluid to electromagnetic energy so as to cause a response related to the magnetization of the fluid before it enters the substance, performing magnetic resonance measurements on the substance to generate intensity information and processing the intensity information to determine perfusion. In one embodiment of the invention, perfusion is measured by labeling atoms in the fluid at a base point, generating a steady state in the substance by continuing to label atoms until the effect caused by labeled atoms perfusing in the substance, reaches a steady state, generating image information for the substance and processing the image information to determine perfusion. It is preferred to label atoms by applying magnetic resonance perturbation. In one embodiment the labeling of atoms involves saturating spins associated with the atoms.

Abstract: The invention is a portable spirometer for measuring the respiration rate of a patient. In detail, the invention includes a housing having a top and bottom, and first and second ends with an air passage extending therethrough. An air flow sensing member is movably mounted within the passage, the member movable forwards and backwards in response to the directional flow of air in the passage as the patient breaths in and out one end of the passage. A position sensing system is mounted within the housing for sensing the position of the air flow sensing member, the sensing system providing a first output signal when the air flow sensing member moves forward and backwards. A circuit is coupled to the sensing system for counting the number of times per unit time the air flow sensing member moves forward and backwards and provides a second signal proportional thereto.

Abstract: A diagnostic method is described for determining the treatment modality for neoplastic (cancer) tissue within the peritoneal cavity of a patient. The method utilizes a laparoscope with a visual display output as well as a radiation responsive instrument. These instruments are employed first to carry out a visual survey of the colon and then a radionuclide survey of the colon to locate concentrations of radiolabeled locator. A next survey is carried out with the radiation responsive instrument to determine the location of lymph node involvement in the cancer as well as other metastatic disease. Should the latter involvement be found, open laparotomy is indicated as the treatment modality. On the other hand, where no lymph node involvement is determined and the region of locator concentration can additionally be visualized, then conventional laparoscopic resection procedure is the determined treatment modality.

Abstract: In a shock wave generating apparatus, phase shifts contained in echo signals reflected from a calculus are corrected in order to clearly judge whether or not such a calculus is actually present at a focal point or a near region.

Abstract: An MRI system includes static and gradient field generators for respectively generating static and gradient fields to be applied to an object, a radio-frequency (RF) field transmitter/receiver for transmitting and receiving an RF field, a sequence controller for applying the gradient field and the RF field to the object at a predetermined timing while the object is being applied with the static field, thereby causing a predetermined MR phenomenon, a signal processor for performing predetermined processing of MR signal data detected through the RF field transmitter/receiver to obtain an MR image, and a display for displaying the image obtained by the signal processor. The sequence controller comprises a multi-slice controller for executing a multi-slice method using a sequence with a relatively long echo time so that an MR signal of a proton of a fat is suppressed and an MR signal of a proton of a CSF is emphasized.

Abstract: Fast NMR pulse sequences are employed to acquire data sets from which a set of images can be reconstructed depicting a patient's heart at successive phases during the cardiac cycle. The number of images is increased by selecting views from adjacent data sets to form interpolated data sets that are employed to reconstruct images depicting the patient's heart at cardiac phases between the successive phases.

Abstract: A method for monitoring the pH of a patient includes the step of providing a magnetic resonance system having a magnet with a bore configured to receive a portion of a finger of a patient without receiving a substantially larger portion of the body of the patient. The method proceeds by inserting the finger of the patient into the bore of the magnet and monitoring the pH level of capillary bed tissue in the finger with the magnetic resonance system. Preferably, the system is configured to monitor the spectrum of phosphorus-31 metabolites in the finger and produce information in the form of a normalized phosphorous integral ratio indicative of the spectral area in order to alert an operator of the occurrence of a condition in which the normalized phosphorous integral ratio is greater than one in the setting of decreasing pH, as indicative of capillary bed tissue shock--lactic acidosis.

Abstract: A connector attached to an end of a twisted wire pair, whose other end has fetal and maternal electrodes. A driving tube is removed from the twisted wire pair by pulling a drive handle and driving tube over the connector. The outer diameter of the connector is smaller than the inner diameter of the driving tube. After the connector is free, it is inserted into a housing of a leg plate, which electrically interconnects terminals of the connector and thereby the electrodes with a remote monitoring device. The housing has finger grips to help hold the housing during the insertion of the connector. The leg plate also has a base which is held in position against a mother's leg and has a ground electrode which is also electrically interconnected with the device. The housing is rotatable relative to the base.

Abstract: A local RF and gradient coil for acquiring images of the human brain using fast NMR pulse sequences includes an end capped RF bird cage coil surrounded by a 3 axis gradient coil assembly. An RF shield is disposed between the RF coil and the gradient coils and it is divided into separate segments to reduce eddy currents induced by the changing gradient fields.

Abstract: There is disclosed a patient immobilization system for repeated use in imaging and radiation therapy of a patient, the system comprising an immobilization plate, side rails mounted on the plate with mask studs outwardly projecting therefrom engaging a thermoplastic immobilization mask with at least two anchor bars holding the mask on said studs, wherein the improvement comprises a relatively rigid plastic arch having two ventricle leg portions and an apex, the lower ends of each of the leg portions being mounted on a respective one of the anchor bars; a flap of material outwardly projecting from the mask to a point adjacent the arch; a fixation member for mounting the outwardly projecting flap of material to the arch whereby the mask can be tightly held between the bars and the side rails on the studs and at a third point to the arch. Contrast material is provided at the apex of the arch and in each of the leg portions such that the x, y, and z axes can be shown in three-dimensional images of the patient.

Abstract: A quadrature local coil includes two coil sets placed on opposite sides of the patient, each coil set having a single loop and a split loop so as to be sensitive to quadrature components of a flux field substantially centered between the coil sets. Signals are developed from the loops in a manner to reduce current flow in the loops preventing coupling of the opposing loops and the degradation of the signal. The signals may be summed to produce a single signal of improved signal-to-noise ratio.

Abstract: Surgery is performed with pulsed heat means that selectively destroys tissue in a region within a patient. The size of the region destroyed is dependent upon the frequency of the pulses of the pulsed heat means and thermal conductivity of the tissue of the patient. The pulsed heat means can be a coherent optical source that is guided by laser fiber to the tissue to be destroyed. In another embodiment the pulsed heat means is a focussed ultrasound transducer that dissipates ultrasonic energy at a focal point within the region of tissue to be destroyed. A magnetic resonance imaging system employing a temperature sensitive pulse sequence creates an image of the tissue and the region being heated to allow a surgeon to alter the position of the pulsed heat means or vary the pulse frequency.

Abstract: The device of the present application, an adhesive disk, relates to non-invasive multi-modality radiographic surface markers and provides means for marking patients and diagnostic images taken of those patients through different methods including X-Ray, Computerized Tomography, Positron Emission Tomograph, and Nuclear Magnetic Resonance Imaging among others. The device of the present application also provides means for enabling the accurate location of internal structures of a patient.

Abstract: An insertable intracavity probe for use in magnetic resonance imaging of an area of interest in a relatively inaccessible region of the body is disclosed. The probe has an internal pickup coil carried at the distal end of a shaft for rectal insertion of the coil and an inflatable anti-migration cuff to hold the probe in position and prevent outward migration thereof during a procedure. The anti-migration cuff is carried on an outer sleeve which is slidably and rotatably mounted on the shaft. The coil is carried on a resilient tip structure at the distal end of the shaft which is flexible in the plane normal to the plane of the coil. Deflection of the coil assembly is controlled by a pair of control lines attached to the distal end of the tip structure. The lines may be selectively tensioned to deflect the coil in the direction of tension by a thumb wheel control at the handle of the probe.

Abstract: A method and apparatus for measuring blood iodine concentration draws a continuous specimen of blood containing iodine from the left ventricle of the heart and exposes that specimen to a source of X-rays. The attentuated level of X-rays passing through the specimen is compared with the unobstructed level of X-rays to determine the concentration of iodine in the blood. The measurement is then corrected to account for the effects of dispersion caused by the travel of the specimen from the heart to the measurement zone.

Abstract: A magnetic resonance imaging receiver system for producing high resolution images of the foot and ankle regions of a human subject. The magnetic resonance imaging receiver comprises an antenna for receiving resonance signals produced by a magnetic resonance imaging, radio frequency excitation magnetic apparatus, a free standing foot cradle assembly for supporting and rigidly holding the foot and ankle of the subject, and a tuning/impedance matching circuit for providing for the maximum transfer of radio frequency energy from the antenna to the receiver unit in the magnetic resonance imaging, radio frequency excitation magnet apparatus. The system utilizes fixed local coils which operate in the receive only mode for receiving electromagnetic signals from resonating nuclei produced by a whole body MRI scanner system or the like to produce high quality images.

Abstract: A medical diagnostic method comprises the steps of automatically sensing an acoustic vibration inside a person, converting the sensed acoustic vibration to an electrical signal, amplifying the electrical signal, and converting the amplified electrical signal to an acoustic pressure wave. The steps of sensing and converting the sensed acoustic vibration to an electrical signal are implemented by operating an acoustoelectric transducer in a hand held device, and the method further comprises the step of holding the hand held device against a skin surface of the person. The method further comprises the steps of wirelessly transmitting the amplified signal to a receiver and printing or displaying the transmitted acoustic information after a processing thereof. The acoustic information or the processed information derived therefrom is advantageously printed in graphic form. Original acoustic information or processed information may be stored for subsequent use in diagnosing a patient.

Abstract: For generating a signal corresponding to the respiration volume per unit of time of a patient, a signal component correlated with the respiration is filtered out of a measured impedance signal acquired in the region of the heart of the patient, and the zero-axis crossings of this signal component are detected and the maximum values respectively arising in between two successive pairs of zero-axis crossings are identified in terms of amplitude. These maxima are added during a prescribed time interval to form a value corresponding to the respiration volume per unit of time.