Abstract: Method for assisting in the maintenance of a balanced stance by a person who has lost the sense of touch in one or both feet. Load signals are generated in correspondence with body weight loads applied at forward and rearward portions of the feet. The load signals are used for creation of tactile stimuli in a spaced pattern on a sensitive skin area of the person.

Abstract: A device to stop bleeding of a part by supplying a heating current to and heating a heating element which is contained in the end part of a probe and whose voltage drop at its ends shows temperature dependency and by applying the end part to the bleeding part. The device includes a resistance installed in series with the heating element, compares the voltage of the resistance with a reference voltage, and controls the heating current value using the comparison output which depends on the temperature increase of the heating element, thus keeping the heating temperature at a temperature suitable for stanching.

Abstract: There is disclosed herein a system for providing control of multiple functions needed to perform eye surgery. A microprocessor based system controls a vacuum generation system using venturis and linear valves and a pneumatic system for driving vitrectomy probes and pneumatic scissors in either a variable frequency, multicut mode or a proportional cut mode where the cutting pressure is proportional to the position of a foot operated position sensor. The frequency of the vitrectomy probe cutting action can also be controlled and the level of vacuum can be controlled from a foot operated position sensor which can also be used to turn on or off a fragmentation device. The footswitch can also be used to turn irrigation fluid on or off, and the flow rate can be controlled from a control on the front panel. By making a certain foot motion in any certain aspiration modes, reflux of the aspiration line can be controlled.

Abstract: A delivery system for brachytherapy comprising a conformable sheet of material which is absorbable in living tissue and a plurality of radioactive seeds in a predetermined array within the sheet. In one form, the sheet is a continuous flexible film in which the seeds are positioned in a predetermined array and which film can be sutured or stapled in place on the surface of a tumor area.

Abstract: A blood pressure cuff is applied about a subject's artery, and inflated above the systolic level thus fully occluding the artery for a full heart cycle. The cuff pressure is thereafter reduced to permit an increasing flow through the progressively less occluded artery, and a measure of the peak amplitudes of the successively encountered blood flow (oscillatory complex) pulses stored in memory. Also retained is the cuff pressure obtaining for each stored complex peak. In accordance with varying aspects of the present invention, the stored complex peak-representing data ensemble is corrected for aberrations; and improved data processing operates on the stored (and advantageously corrected) pulse peak data and the corresponding cuff pressure information to determine the subject's mean arterial blood pressure.

Abstract: Acoustic signals generated by muscles during contraction are used, in accordance with the invention, to generate signals responsive to muscle activity, measure muscle fatigue and excitation-contraction decoupling, provide a biofeedback response, control cybernetic systems, and control prosthetic devices. Such myoacoustic signals, when compared against myoelectric signals permit the extent of contraction of muscles to be compared against the excitation thereto. Moreover, a plurality of such myoacoustic signals can be compared synchronously against one another in a multichanneled recorder to analyse dynamic muscle problems, such as situations which result in poor posture and improper gait. These myoacoustic signals can also be used to drive prosthetic devices which are currently driven by myoelectric signals. It is an advantage of the present invention that myoacoustic signals can be analyzed using circuitry which is currently available and in use for analyzing myoelectric signals.

Abstract: In a method for the application of cuts, perforations and/or microlesions to biological material, such as cell agglomerates, individual cells or chromosomes, by means of laser pulses fed into a microscope, the laser pulses are focussed to a cross-section which is limited by diffraction phenomena, and the nth order diffraction maxima (n=1, 2, 3, . . . ) of the laser pulses are used to apply the cuts.

Abstract: This unit is for stopping hemorrhage by supplying a current for heating to a semi-conductive thermal element of small heat capacity to insure good heat response which is incorporated in the distal extremity of a slender probe, and possesses a means to recognize whether, or not, voltage fall between the both ends of the thermal element is within the permissible range in order to make it possible to detect qualitative deterioration of thermal element.

Abstract: A method and apparatus for removing cataracts in which a flexible line preferably 1 mm or less in diameter is inserted through an incision into the anterior chamber until its end is adjacent the cataract. Coherent radiation, preferably at a frequency between 193 and 351 nm, is coupled to the cataract by an optical fiber in the line. An irrigation sleeve provided about the fiber and an aspiration sleeve extending partially around the irrigation sleeve conduct irrigating liquid to and remove ablated material from the anterior chamber and form with the optical fiber the flexible line.

Abstract: A microprocessor controlled electrosurgical generator provides plural ground-isolated and mutually isolated monopolar r-f cutting signals for respective surgical pencils to permit plural surgeons to use the same generator while maintaining independent control over output power and mode selection. A bipolar output signal is also isolated from ground and from the monopolar signals so that the removal of the dispersive patient return pad is not required when changing between monopolar and bipolar operation. Adjustment of the r-f cutting signal power level is effected by providing an adjustable d.c. bias level for an output amplifier. The d.c. bias level is derived from an a.c. control signal which is duty-cycle modulated in accordance with selected r-f power level settings.

Abstract: A ventriculostomy tube having a semi-rigid body and a fluid transmissive passageway extending from a first end to a second end of the tube is inserted through an aperture in a skull. The first end of the tube includes a port for establishing fluid communication between the passageway and a fluid space within the brain tissue surrounding the tube known as the lateral ventricle. By establishing fluid communication between the lateral ventricle of the brain and the second end of the tube, the ventriculostomy tube enables intracranial pressure to be continuously monitored. An electric current is passed through electrical leads extending along the length of the ventriculostomy tube to a thermistor which is secured to the exterior surface of the tube at a first elevation to measure the temperature of the brain tissue at a first elevation.

Abstract: The invention contemplates controlled ablation of the cornea, using ultraviolet laser radiation, wherein irradiated flux density and exposure time are so controlled as to achieve desired depth of the ablation. Sculpturing action results from controlled change of projected laser-spot size, in the course of a given treatment, wherein, in one illustrative case, projected laser-spot size ranges from a maximum which covers the entire area to be treated, down to a predetermined minimum tolerable size, wherein cornea-curvature change is myopia-corrective. Further illustrative techniques and situations are also disclosed, for achievement of hyperopia correction, for astigmatism correction, and in connection with corneal-transplant operations.

Abstract: The invention contemplates controlled ablation of the cornea, using ultraviolet laser radiation, wherein irradiated flux density and exposure time are so controlled as to achieve desired depth of the ablation. Sculpturing action results from controlled change of projected laser-spot size, in the course of a given treatment, wherein, in one illustrative case, projected laser-spot size ranges from a maximum which covers the entire area to be treated, down to a predetermined minimum tolerable size, wherein cornea-curvature change is myopia-corrective. Further illustrative techniques and situations are also disclosed, for achievement of hyperopia correction, for astigmatism correction, and in connection with corneal-transplant operations.

Abstract: Functional electrical stimulation of regions of the skin of disabled individuals is achieved by delivering an energizing electrical signal via an electrode located in the region where the development of pressure sores is desired to be inhibited. Such electrical stimulation produces pressure variations as a result of tissue undulation at the interface where the skin of the human being meets a surface, such as the seat of a wheelchair. Additionally, blood flow is increased, muscles operate as blood pumps, and tissue bulk is increased. Electrical stimulation can be used to improve the conditioning of muscles of individuals who have been disabled for a long period of time, and the muscles have consequently atrophied, so that the beneficial effects of electrical stimulation to prevent or reduce the possibility of pressure sores is achieved.

Abstract: A pulse width modulation technique regulates the output power of each cycle of a radio frequency surgical signal of an electrosurgical generator. The delivered power of the surgical signal is determined by multiplying the sensed current and the sensed voltage of the surgical signal. An error signal is established by the difference of the actual delivered power with respect to a selected desired output power. The error signal is operatively utilized to modulate the pulse width of each driving pulse which creates the cycles of the surgical signal. Limits on the sensed voltage and sensed current signals are established to limit the output characteristics of the surgical signal. A minimum current limit signal is utilized to limit the maximum output voltage into relatively high impedances. A minimum voltage limit signal is utilized to limit the maximum output current into relatively low impedances.

Abstract: The invention contemplates use of a scanning laser characterized by ultraviolet radiation to achieve controlled ablative photodecomposition of one or more selected regions of a cornea. Irradiated flux density and exposure time are so controlled as to achieve desired depth of the ablation, which is a local sculpturing step, and the scanning action is coordinated to achieve desired ultimate surface change in the cornea. The scanning may be so controlled as to change the front surface of the cornea from a greater to a lesser spherical curvature, or from a lesser to a greater spherical curvature, thus effecting reduction in a myopic or in a hyperopic condition, without resort to a contact or other corrective auxiliary lens technique, in that the cornea becomes the corrective lens. The scanning may also be so controlled as to reduce astigmatism and to perform the precise incisions of a keratotomy.

Abstract: A method of diagnosis of the type of tissue in an artery, including distinguishing artery wall from atheromateous plaque is described, in which a catheter with one or more optical fibers is enclosed at a distal end by an optical shield transparent to light radiation and wherein the proximal end of the catheter and optical fibers are coupled to a source of optical radiation. The catheter is inserted into an artery until the optical shield is brought into contact with a suspected arterial lesion or other tissue to be diagnosed.An optical fiber is selected and light coupled from the source at a wavelength of about 480 nm enters the proximal end of the optical fiber and is transmitted by the selected optical fiber to the distal end out the optical shield and impineges on the suspected lesion.

Abstract: A system for controlling the movement of a human knee joint during stimulated flexion thereof. The system includes a brace having an over-center hinge at the knee joint. This hinge causes the knee joint to lock under load when the hinge is opened less than a predetermined angle. A sensor senses the angle of opening of the hinge joint and generates a corresponding sensing signal for use by a computer connected for controlling the stimulation of the knee. The computer is programmed for avoiding increases in the stimulation signal when the hinge joint has an angle of opening which is less than some predetermined angle greater than zero and not greater than the critical angle of the hinge.

Abstract: A pulsed laser for medical application and particularly for ophthalmological treatment is described.The laser beam pulse has a clearly defined polarization plane. By rotating a polarization splitter cube, it is possible to regulate the energy of the laser beam pulse.Following each rotation of the polarization splitter cube, and prior to the following treatment pulse, a control system releases a test pulse. The energy of the test pulse is measured while the shutter closes the treatment beam path.According to a preferred embodiment, the laser is a neodymium-YAG laser.

Abstract: A transcutaneous nerve stimulation device is provided using a common controller for both output pulse production and treatment parameter display. The common controller, which preferentially takes the form of a programmed microprocessor, is connected by signal lines to both the pulse output circuitry and the display, which are controlled by time-sharing the signal lines. The controller is responsive to operator entered input signals for the calculation of output pulse characteristics and display parameters. During a majority of treatment time, the controller is providing signals on the signal lines for control of the display. The display signals are interrupted during timed intervals when output signals are produced.