Abstract: An apparatus for ultrasonic irradiation of the heart either when the chest is open after surgery or through the chest wall. It may also be used in conjunction with electrical defibrillation equipment or alone. The apparatus includes an EKG for detecting the heart beat, an ultrasonic generator and timing and pulsing circuits for providing timed pulses of ultrasound to coincide with selected events in the cardiac cycle.
November 1, 1985
Date of Patent:
March 24, 1987
Canadian Patents and Development Limited
George V. Forester, Alan J. Mortimer, Orest Z. Roy
Abstract: By using a deconvolution technique, the outputs of a speech processor to the electrodes, based on current spread curves, the proper outputs of each eletrode are determined to provide the desired stimulation of the nerves. It has further been found that either overestimation or underestimation of the problem will result in improper stimulation and, in fact, a diminished accuracy of stimulation of the nerve rather than enhanced stimulation.Thus, the method relies on an inverse convolution of what amounts to the known desired stimulation of the auditory nerves to determine what information should be provided at the electrodes which are connected to the output channels of the stimulator system.
May 16, 1985
Date of Patent:
March 10, 1987
The Board of Trustees of the Leland Stanford Junior University
Abstract: A biological monitoring probe carrier incorporating a spiral retaining coil is easily put in place by a drive wrench passing through a guide channel with a longitudinal slot. Said channel holds the probe carrier near its distal end and holds a monitor cable alongside a shaft of the drive wrench which includes means for engaging the probe carrier to turn and advance it for the purpose of securing to tissue the retaining coil embedded in the distal end of the carrier. The proximal end of the wrench shaft includes a manipulating means for advancing the wrench a predetermined distance once the guide channel is placed against the tissue. The drive wrench is then withdrawn and the cable may then be released as the guide channel is withdrawn by allowing the cable to slip freely through the slot without need for disconnecting the monitor apparatus from the proximal end of the monitor cable.
Abstract: An exemplary electrode arrangement comprises an elongated electrical conductor with a covering of electrical insulation and with an electrode head electrically connected to the distal end of the conductor for supplying stimulation pulses to the heart. The electrode arrangement includes a filamentary element or elements for fixing the conductor assembly to a cardiac wall. In order to be able to flatten the or each element closely against the conductor assembly and to anchor the electrode head securely in the trabeculae and to nonetheless facilitate a subsequent positional correction of the electrode head in the heart, it is inventively proposed that the or each filamentary element be of soft, flexible material and extend in a plane perpendicular to the axis of the conductor, the or each element preferably at least partially encircling the conductor assembly at a substantial spacing therefrom.
Abstract: Optimization of nerve fiber stimulation to substantially increase the activity of the then selected nerve fibers is disclosed, with optimization being achieved through utilization of electrical pulses that are caused to occur in a predetermined pattern with respect to polarity, spacing, frequency and duration so as to interact with the electro-neurophysiological characteristics of the particular nerve fibers then to be electrically stimulated.
Abstract: An electrode probe (1), in particular for electrical stimulation of the heart from the interior of the esophagus, is constructed on the basis of the new finding that the distance from the transition between the stomach and the esophagus to the transition between the left atrium and the left ventricle is substantially the same in adults. The electrode probe (1) has a maximum of two stimulation zones (A, B) (one for atrium and ventricle, respectively) which, when fitted on expansible parts of the probe, allows heart stimulation to be performed with simple equipment without expert assistance, when the distance between a means (4X) for fixing the axial position of the probe in the esophagus and the stimulation zones (A, B) are determined in accordance with the above finding, so that in all conditions optimum stimulation of the heart and reduction in the required stimulation voltage are obtained.
Abstract: Method and apparatus for stimulation of cells in arrhythmic myocardial tissues includes depolarizing the cells by application of a first electrical pulse or shock followed by a second electrical pulse having a polarity opposite to the first pulse. Finally, a third pulse having the same polarity as the first pulse is applied to the cells. Specific relationships between the magnitudes and durations of the pulses are advantageously employed for achieving the most desirable stimulation results.
Abstract: A physiological instrument that includes a first component comprising an ECG monitor and a second component comprising a defibrillator. The second component may also include a pacemaker mounted to and electrically connected with the defibrillator. The first and second components may communicate with one another entirely by means of three optical communication channels, each channel including an optical signal path that includes windows through which the optical signals pass into and out of the components. The components may therefore operate in a fully integrated manner despite the fact that no electrical signal path exists between the components.
January 8, 1985
Date of Patent:
January 13, 1987
Douglas T. Hakala, Joseph M. Bocek, James G. Osborn
Abstract: In a physiological signals processing system including (a) a A/D conversion means for converting physiological signals into digital signals and (b) a data compression means for reducing the number of data points sampled from said digital signals, the improvement which comprises: said data compression means being provided with a first sampling means for sampling a pair of combined peak points from said digital signals by applying the second order differential conversion to said digital signals, and a second sampling means for sampling level points by the level detection of said digital signals in the portion where adjacent peak points are not combined.
Abstract: An optical thermodetector for in vivo testing of tissue is disclosed which has a housing including a case and a needle-like extension projecting therefrom, the extension having a sharp end for piercing the skin of a patient, a temperature element disposed within the housing and having indicating means responsive to a predetermined change in temperature, and an optical element disposed within the housing for recording coloration of tissue. The recording of coloration of tissue takes place as the extension is withdrawn from a depth within the skin of a patient. The recordation on film of the coloration of the tissue corresponds to the recordation of the temperature.
Abstract: A nerve-stimulating electrode assembly for installation within or adjacent the lower end of the dura mater to enable regaining of at least partial control over lower-body functions directed by nerves emerging from the end of the spinal cord. In one form, the electrode assembly has an internal passage enabling injection of fluids, whereby electrical stimulation, chemical treatment, or both forms of therapy may be used either intra- or extradurally.
Abstract: Normal nerve function is restored across severed ends of a nerve fascicle by inserting between the severed ends a laminated chip perforated with an array of holes each sized to accommodate approximately one axon and each containing at least two electrically conductive regions in ohmic contact with the inner surface of the hole at discrete locations along the axial direction of the hole. Proximal axon segments are permitted to propagate through the holes to join distal segments in random fashion and to be in contact with each of the two electrical contacts. Each contact is part of a circuit pattern capable of monitoring impulses, applying blocking potentials and placing selected pairs of proximal and distal axon segments in electrical contact such that nerve impulses can be routed as desired to restore normal nerve impulse communication and hence nerve function.
Abstract: A simplified transcutaneous nerve stimulating device is disclosed that combines simplicity of structure with dependability of operation. The device utilizes a 45 volt battery source for circuitry simplification by eliminating the need for circuitry such as voltage multipliers, with the battery source powering an oscillator and a pair of constant current regulated drive circuits from which pulses are alternately coupled to isolated output pairs connectable with electrodes positionable on the skin of a user for imparting stimulation pulses to the body of the user for pain suppression.
Abstract: A visual prosthesis for blindness due to retinal malfunction includes a compact device having a close-packed array of photosensitive devices on one surface thereof. A plurality of electrodes extend from the opposed surface of the device and are connected to the outputs of the photosensitive devices. The device is adapted to be inserted in the posterior chamber of the eye, generally disposed at the focal plane of the optical pathway and impinging on the retina. Anchoring means secure the device with the electrodes operatively connected to the neuron array at the surface of the retina to stimulate the neurons in a pattern corresponding to the illumination pattern of the photosensitive array. The device is powered by externally induced electromagnetic or radio frequency energy, and is encased in a biologically inert housing. An amplifier array may be interposed between the sensing elements and the electrodes to amplify, shape, and time-process the visual signals.
Abstract: A nerve trunk (A) has an annular electrode cuff (B) positioned therearound for imposing electrical signals on to the nerve trunk for the purpose of generating unidirectionally propagated action potentials. The electrode cuff includes an annular cathode (30) having a circular passage therethrough of a first diameter. An annular anode (40) has a larger circular passage therethrough of a second diameter, which second diameter is about 1.2 to 3.0 times the first diameter. A non-conductive sheath (50) extends around the anode, cathode, and nerve trunk. The anode and cathode are placed asymmetrically to one side of the non-conductive sheath. Specifically, a first length (L1) along the electrode sheath between a first end (56) and the cathode is at least twice a second length (L2) between the anode and cathode. A third length (L3) between the anode and a second end (58) of the conductive sheath is smaller than the first or second lengths.
Abstract: A monitoring circuit for use in conjunction with an electrical stimulator and an electrical monitor, such as an EKG monitor, having a differential amplifier input. The circuit functions by equalizing the electrical signals due to the stimulator on both inputs of the electrophysiological monitoring device. Because the stimulator induced signals appear at equal levels on both inputs, the differential amplifier of the monitoring device will cancel them out, allowing display of the underlying physiological signals.
Abstract: Migraine modulator apparatus and methodology employs a transcutaneous electronic wave to reduce and control migraine headaches. A first positive contact electrode is placed at the pain site and a second positive contact is placed at the web of the contra-lateral hand; a first negative contact is placed at the contra-lateral trapezius origin, and a second negative contact electrode is placed at the web of the ipsilateral hand. An electronic current wave comprising relatively high frequency pulses with a low frequency amplitude modulation is then applied between the positive and negative electrodes.
Abstract: An implantable microprocessor-controlled dual chamber heart pacemaker is programmed to control the timing of the pacing of the ventricle in response to high rate atrial signals. The microprocessor operates in conjunction with an atrial timer to detect atrial signals which occur at a rate in excess of a predefined atrial rate limit. The microprocessor paces the ventricle at a predefined desirable demand rate and inhibits pacing of the atrium in response to the high rate atrial activity. The microprocessor also controls the timing of an atrial refractory interval which includes an absolute refractory portion during which atrial signals are not detected and a relative refractory portion during which atrial signals are detected but are not tracked. The combined absolute and relative atrial refractory portions insure that relatively high rate atrial signals are detected and spurious signals conducted from the ventricle are ignored.
May 7, 1985
Date of Patent:
November 25, 1986
Ross G. Baker, Jr., Richard V. Calfee, Richard S. Sanders, Joe Vandegriff, Jay Warren
Abstract: A method and apparatus for establishing a stress index S of a subject by determining from the EKG of the subject the peak valve of the R-wave and the T-wave; determining the ratio of the R-peak to the T-peak as an initial stress value Z; determining the corresponding stress value Z after the subject experiences stress or relief of stress and establishing the stress index S as the ratio of the Z values (after/before). A stress meter is proposed to provide visual or other indications of the instantaneous stress index. Methods of exercising subjects or treating subjects in accordance with stress index values are disclosed.
Abstract: A muscle stimulator system produces an electrical output pulse train which provides functional electrical stimulation (FES) of muscles or muscle groups. The muscle stimulator system includes a clinical device (which is line powered and independently programmable) and a battery-operated personal device (which can be programmed using the clinical device). In addition, external memory modules are provided to store the FES regimens established in the clinical device during the PROGRAM mode. The clinical device is capable of retrieving the FES regimens from the external memory module. The personal device includes a manually operated amplitude control which provides an amplitude control signal for controlling the amplitude of the output pulse train.