Abstract: An apparatus and a process are disclosed for communicating an electrogram from a patient. An enclosure having a tuned coil mounted therein is implanted in the patient. The tuned coil is adapted to reradiate a signal in the presence of an externally generated carrier signal. A variable impedance device is provided across the tuned coil. The resistance of the variable impedance device can be altered linearly and it is set at a reference level that is approximately the center of its linear range. An analog signal, representative of the electrogram, is coupled to the input of the variable impedance device. In this manner, the variable impedance device will be modulated in response to the electrogram.

Abstract: A dual chamber pacemaker system is disclosed with means for operating in one or another of alternate rate adaptive modes. The pacemaker incorporates an atrial synchronous mode, wherein, pacing rate is determined as a function of sensed atrial signals. It also incorporates a T.sub.x mode, wherein pacing rate is controlled by a sensed QT interval, and an extra sensor mode, wherein pacing rate is controlled as a function of at least one sensed body parameter. The pacemaker comprises means for automatically testing the applicability or appropriateness of the mode currently in use, and for automatically selecting the appropriate rate control mode.

Abstract: Ventricular fibrillation (VF) is detected by comparing the electrocardiogram (ECG) waveform of the patient's heart against a stored library of compilation of waveform characteristics of various heart conditions as recorded by an ECG. Since the waveform for ventricular fibrillation of arrythmias are completely unformed compexes, disorganized and irregular, the presence or absence of any of the stored or library features in the patient ECG is used as the criteria for diagnosing VF and automatically subjecting the patient to a prescribed electroshock therapy.

Abstract: This invention essentially relates to a method of using a pulse generator for aesthetic treatment of the skin with a view to removing wrinkles, puckers or the like therefrom, which consists in connecting to the said pulse generator a needle which is introduced immediately under the skin and in substantially parallel relationship to the wrinkle or pucker to be removed, and in making pass through the said needle a weak current of preferably low frequency comprised between about 100 and 500 cps to thus fill up the depression of the pucker or the wrinkle.

Abstract: An endocardial electrode assembly of three or more spring legs to be inserted into the heart, sets of electrodes on respective spring legs comprising distinctive geometrical patterns, over the ventricle-contacting span of the legs, such that the active sets of electrodes provide recognizable patterns when within a ventricle of the heart and viewed with a fluoroscope, the respective locations of at least some of the electrodes of these patterns being staggered relative to electrodes on other legs in the manner to reduce lateral clumping, thus to permit the numerous electrodes to be housed in a catheter sized to be conveniently introduced into the heart.

Abstract: A method for growth promotion in animals consists in percutaneous application of an electromagnetic field having a frequency of from 25 to 150 MHz and a power of from 30 to 40 W, to the region of the epididymal lobules of the spermatic cords and the epididymides, said application of an electromagnetic field being carried until a subcutaneous induration appears in the aforesaid region, that is, within an exposure time of from 10 to 20 s.

Abstract: A transvenous, endocardial heart pacemaker lead having a conical fixation device on its distal end for holding a distal tip electrode in proper pacing position within the heart. There are open spaces around the conical surface of the fixation device defined by spaced apart, circumferential rings interconnected with spaced apart ribs extending lengthwise along the conical device. Engagement of trabeculae of the heart within the open spaces and against the rings holds the lead in place.An electrical conductor contained within an insulating sheath or catheter connects the distal tip electrode with a source of power. The conical fixation device is made out of flexible, nonconducting material.

Abstract: Disclosed is a method and apparatus for maintaining the potential between a cathode and a reference electrode substantially constant during electrically-induced osteogenesis. Two separate embodiments of electronic circuits are provided which will generate a D.C. current to flow between a cathode and anode while maintaining the potential between the cathode and the reference electrode substantially constant within the range of 0.1 to 1.26 Volts and preferably within the range of 1.0 to 1.26 Volts. Improvement in the amount of new bone grown over prior art bone growth stimulators is on the order of 200 to 300 percent. The electronic circuits provide the substantially constant cathodic potential over a wide range of load impedances between the anode and cathode. The disclosure is applicable not only to improving osteogenesis in bone fracture sites, but also to applications in which it is desirable to provide bone accretion for any reason.

Abstract: A synchronizable heart pacemaker includes a timing circuit, a differentiating circuit for receiving signals, and an interference recognition circuit connected to the output of the differentiating circuit. The interference recognition circuit includes a testing stage for each signal. An output signal normally appears on an output of the testing stage, and the testing stage includes a peak detector circuit which stores a positive maximum value and a negative maximum value of each signal differentiated by the differentiating stage, and an adder forming the sum of said maximum values. A discriminator stage is postcoupled to the testing stage.

Abstract: The programming of pulse intervals and the inhibition of the output of an implanted cardiac pacemaker are disclosed. The occurence of either an output pulse from the implanted unit or of cardiac activity allows for synchronization of the programming unit with the implanted device so the external programmer can control the pulse timing sequence of the implanted unit. The implanted unit can be programmed after each pulse, or as required, to obtain a pulse sequence which may be used to provoke, or terminate, tachyarrhythmics thus enabling non-invasive electrophysiologic studies, or therapeutic stimulation.

Abstract: A heart rate monitor for use where direct contact with a patient cannot be made utilizes two continuous radio frequency (RF) signals, one of relatively low frequency and one of relatively high frequency directed toward the patient whose heart is to be determined. Doppler shifted signals are reradiated by the patient back to the monitor. The reradiated low RF signal has doppler components due to bodily motion caused by respiration and heartbeat. The reradiated high RF signal has doppler components due to patient bodily movement caused by respiration. Doppler components due to heartbeat if any, are of substantially lower value than those associated with the low RF signal. The heart rate monitor includes a difference amplifier which effectively subtracts the doppler signal associated with the high RF frequency from the doppler signal associated with the low RF frequency to obtain a signal which contains only components due to the heartbeat of the patient.

Abstract: A physiological device adapted for implantation in a human patient, e.g. a cardiac pacemaker or muscle stimulator, characterized by having programmable means for generating data and assembling same for presentation of one or more histograms. The implanted device has circuitry for registering the occurrence of sensed or evoked events, as well as device operating events such as cycles of operation, and means, preferably software control of a microprocessor, for classifying registered events into respective classes of one or more parameters associated with the events and for accumulating counts of events for each such class. The system also includes external apparatus for communicating programmed instructions to the device, whereby histogram selection and histogram classes are programmed, and for receiving the histogram data transmitted from the implanted device and displaying it in a convenient histogram form. Time based histograms are also generated, utilizing a software clock for continuously tracking time.

Abstract: The present invention is a sensing amplifier circuit for a tissue stimulator (72) for supplying or attenuating far field signal voltage artifacts comprising a full differential amplifier having a first (94, 136) and second (96, 142) stage amplifiers for respectively receiving a second and first signal voltage output from a sensing mean (80, 82), and a switch means for controlling an input of the second signal voltage output from said sensing means to the first stage amplifier (94, 136).

Abstract: An electrical energy source, particularly suitable for portable emergency equipment such as cardiac defibrillators, uses a small explosive charge of which the energy is converted into a short intense electrical pulse by an electromechanical convertor for example a piezoelectric transducer.

Abstract: Apparatus for stimulating osteogenesis in a living body comprises a portable, light weight, self-contained, low drain, battery powered stimulating instrument adapted to be carried by a patient during treatment for applying a high frequency alternating current treatment signal to the skin of the patient according to a treatment program and for generating a readable record of a parameter of the treatment signal during the treatment program, and a clinical control instrument in the custody of a person supervising the treatment program and connectable to the stimulation instrument when desired for monitoring the condition of the latter and for reading out data recorded therein during the treatment program.

Abstract: The present invention discloses human headache relief by application of electrical pulses of an approximate frequency of 10-12 pulses per second to a headache sufferer's skin. Ideally, the pulses are of an amplitude just below the sufferer's pain tolerance level (typically 60 to 150 volts) and are applied by two electrodes: a ground electrode makes contact with any skin area away from the neck or head and a live electrode makes contact with the sufferer's neck or head, depending on the type headache suffered. Further, the pulses preferably have a square wave form with the pulse width approximately 40 microseconds. An application for two minutes is normal and usually provides at least 6 hours relief.

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: Apparatus and method for therapeutic treatment of persons having paralyzed legs. The apparatus and method make use of four sets of transcutaneous electrodes which are placed above the iliac and quadriceps muscles of the paralyzed person. The person is seated upon an exercycle, and a series of pulsed stimulation signals are applied to the electrodes to cause coordinated contraction of the iliac and quadriceps muscles. This causes pedaling of the exercycle by the paralyzed legs. A position sensor senses the position of the pedals and transmits an indication thereof to a computer which generates control signals for stimulation driving circuits connected to the stimulation electrodes. A pair of paddle controllers are connected to the computer for manual adjustment of the stimulation amplitude.

Abstract: An attachment for use in connection with ultrasound transducers to assist in conducting various surgical procedures involving the withdrawal of fluid from or injection of fluid into selected body organs or biopsies of various organs. The attachment serves to accurately guide a needle or catheter into the selected site scanned by the ultrasound transducer. The device employs a removable and rotatable guide that provides for the use of instruments of different sizes for insertion in body parts within a wide range of angles.

Abstract: A non-destructive testing technique, particularly suitable for the non-invasive examination of human body tissue, wherein the object of interest is transilluminated with multi-wavelength light. Apparatus for practicing the technique generates transillumination light containing different colors and the light which passes through the tissue is divided and filtered to provide plural light beams lying in separate wavelength ranges. These light beams are detected by a video system which provides information bearing signals to data processing circuitry which determines the transmissivity at each wavelength of each point of the object within the viewing field.