Abstract: A non-invasive method and equipment for the evaluation of the flexibility of the spine of a patient and identification of possible mechanical injuries in the lumbar portion of this spine. A string of skin-markers is fixed onto the skin of the back of the patient in the midline of his spine from at least cervical vertebra C.sub.7 down to at least sacral vertebra S.sub.3. Two other skin-markers are fixed onto the skin of the back of the patient in a bilateral and symmetrical manner on the crests of his ilium. The relative positions of all the skin-markers are then monitored and recorded as he flexes forward in this sagittal plane and the so recorded positions are processed to determine the ranges of hip and spine motions in the sagittal plane, which can be compared with each other and with results obtained from a group of "normal" patients to determine any discrepancy or singularity in the flexibility of the spine.

Abstract: Surgical apparatus which includes a waveguide, for example an optical fibre, through which laser energy is applied to tissues for such purposes as ablation of atheroma, destruction of calculi and lithotripsy. The optical fiber is provided with an end-piece through which it passes, and terminates flush with the distal end in the end-piece. For various applications at least the tip of the end-piece may be made either highly reflective or highly absorptive of the laser radiation. A balloon catheter may be fitted over the optical fibre. The end-piece may be provided with sensing means.

Abstract: An oximeter sensor assembly (40) includes a thin elongated flexible sheet-like strip (42) having an integral end portion (44) flexibly wrapping at least partially around a human body part (26), a plurality of electrical conductors (46-50) on the strip, and light emitting and receiving electrical components (28a, 30a) mounted on the strip on the end portion and electrically connected to the conductors. Flexible conductive encompassing shielding layers (62, 66) are also provided, together with outer insulating layers (61, 67). Connection adapter structure (94) is also provided.

Abstract: A method is disclosed for using quasielastic light scattering to determine the degree of cataractogenesis of a lens in vivo. By collecting and analyzing light scattered from the lens, it is possible, using the autocorrelation function or the power spectrum, to separate the fluctuations into two components: one caused by fast diffusing proteins and one caused by slow diffusing protein aggregates. This data may be applied to an experimentally determined and theoretically deduced universal curve in order to determine quantitatively the degree of cataractogenesis at that particular location in the lens.

Abstract: A pulse oximeter apparatus characterized in that it comprises a bandpass filter adapted selectively to exclude motion artefact from wanted signal is disclosed.Also disclosed is the use of such an apparatus for the determination of pulse rate and/or arterial blood oxygen saturation.

Abstract: A respiratory CO.sub.2 detector (10) comprising an infrared lamp source (44) and an infrared detector (50) responsive thereto forming an optical path for detecting the change in CO.sub.2 concentration, or an obstruction in a cuvette (42). The output of the infrared detector (50) provides a high and low voltage signal to be applied to a feedback control loop (12) and to an output circuit (14).The feedback control loop (12) includes a peak detector (22), a contamination detector (24), a pulse-width modulator (26) and a low pass filter (28), the latter providing a DC bias on the infrared lamp (44). The peak detector (22) is connected to the pulse-width modulator (26) to maintain the lamp voltage constant and is connected to comparators (56,62) to compare both outputs of the peak and contamination detectors (22,24). The contamination detector (24) will respond to blockage in the cuvette (42).

Abstract: A biomagnetic analytical system for sensing and indicating minute magnetic fields emanating from the brain or from any other tissue region of interest in a subject under study. The system includes a magnetic pick-up device constituted by an array of fiber-optic magnetic sensors mounted at positions distributed throughout the inner confines of a magnetic shield configured to conform generally to the head of the subject or whatever other body region is of interest. Each sensor yields a light beam whose phase or other parameter is modulated in accordance with the magnetic field emanating from the related site in the region. The modulated beam from each sensor is compared in an interferometer with a reference light beam to yield an output signal that is a function of the magnetic field being emitted at the related site.

Abstract: A magnetic coupling for translatorily movable bodies that is made in one position, is arranged so that it can be broken, without external control, in another position. For this purpose the first body has a coupling element of permanently magnetic or magnetizable material, the second body has at least one complementary coupling element of permanently magnetic or magnetizable material, and a third body has a coupling element of permanently magnetic or magnetizable material cooperating with the second body. Arranged between the complementary coupling element of the second body and the coupling element of the third body that is a spacer which can be moved as desired between the working positions.

Abstract: An efficient method and apparatus for magnetically stimulating the neural pathways of a higher level organism, namely the human body, is disclosed. The method includes selectively applying sinusoidally fluctuating electric power to a stimulator coil that overlies the neurons to be stimulated. The frequency of the power and, thus, the period of magnetic field produced by the coil is chosen to correspond to the time constant of the neurons to be stimulated. Realizable values fall in the range of 1.25 to 1.43 times the time constant of the neurons to be stimulated. The current and voltage of the applied power are in phase quadrature with the current lagging the voltage. During the first polarity (e.g., positive) excursion of the applied voltage, the magnetic field produced by the coil is insufficient to stimulate the underlying neurons, i.e., create a neuron depolarizing electric field. Rather, stimulation occurs during the second polarity (e.g., negative) excursion of the applied voltage.

Abstract: An apparatus for use in measuring fetal blood flow characteristics. The apparatus includes a non-invasive pulse oximetry probe that is inserted into the uterus between the fetus and the uterine wall. The probe is deformable and is positively attached to the fetal tissue surface using a vacuum pump which causes the probe to deform from a pre-set curvature to the curvature of the fetal tissue surface and to form a gasket-type seal with the fetal tissue surface. The probe is manually inserted into the uterus using a curved insertion tool, and is shaped to fit through a slightly dilated cervix. In a preferred embodiment, the probe includes fetal and maternal ECG sensors and additional sensing devices, and is provided with apparatus for improving the efficiency of the pulse oximetry optics.

Abstract: The object of the invention is to provide an instrument for converting a physiological pulse rate into a corresponding linear output voltage.The instrument (1) which accurately measures the rate of an unknown rectangular pulse wave (9) over an extended range of values, comprises a phase-locked loop (8) including a phase comparator (4), a filtering network (6), and a voltage-controlled oscillator (5), arranged in cascade. The phase comparator has a first input (10) responsive to the pulse wave and a second input (11) responsive to the output signal of the voltage-controlled oscillator. The comparator (4) provides a signal dependent on the difference in phase and frequency between the signals appearing on the first and second inputs. A high-input impedance amplifier (16) accepts an output from the filtering network and provides an amplified output DC signal to a utilization device (16) for providing a measurement of the rate of the pulse wave.

Abstract: An apparatus and method for regulating tissue growth in vivo are provided. The apparatus includes a magnetic field generator and a magnetic field detector for producing a controlled, fluctuating, directionally oriented magnetic field parallel to a predetermined axis projecting through the target tissue. The field detector samples the magnetic flux density along the predetermined access and provides a signal to a microprocessor which determines the average value of the flux density. The applied magnetic field is oscillated at predetermined frequencies to maintain a preselected ratio of frequency to average flux density. This ratio is maintained by adjusting the frequency of the fluctuating magnetic field and/or by adjusting the intensity of the applied magnetic field as the composite magnetic flux density changes in response to changes in the local magnetic field to which the target tissue is subjected.

Abstract: An apparatus for detecting and treating abnormal electrical conducting tissue of an organ of the body which comprises a catheter insertable within a blood vessel or body cavity into proximity with the organ to be treated. An electrode or other electrical field-producing element is carried within the catheter and is effective to produce an electric field capable of inducing abnormal movement of the organ, e.g., a cardiac arrhythmia, when the electrode is placed at or near the focus of the abnormal electrical conducting tissue of the organ. A relatively undistorted image of such abnormal tissue is obtained using optical phase conjugation of a low energy laser beam which is directed to the focus of the damaged tissue and the along one or more optic fibers carried within the catheter to a viewing apparatus. A laser beam transmitted through another optic fiber carried within the catheter is then employed, if necessary, to destroy the damaged tissue.

Abstract: A non-invasive, electro-optical sensor probe and a method for its use are disclosed. The sensor probe measures light extinction during transillumination of a portion of blood-perfused tissue. A malleable layer makes the sensor particularly well-suited for attachment to a central site, such as the patient's tongue, cheek, gum or lip, to provide accurate oxygen saturation and pulse rate readings for patients with lowered or inconsistent peripheral circulation.

Abstract: The nocturnal penile tumescence and rigidity monitor includes a penile cuff formed on a nondistensible flexible membrane with an internal chamber defined therein. The chamber is initially filled with liquid from a reservoir until the cuff contacts the periphery of a flaccid penis. The flaccid penile diameter is correlated with the amount of liquid in the cuff by use of a weight sensor signal. During penile expansion, liquid in the cuff is displaced into the fluid reservoir and the tumescence is correlated with the amount of liquid displaced from the cuff by making a weight measurement of the reservoir after such liquid displacement. The weight sensor provides signals that permit a continuous plot of penile tumescence on a strip chart. When the penile tumescence is at a predetermined reference magnitude, a rigidity test is started.

Abstract: A stand for reproducibly ascertaining the posture of a free-standing human being, includes a base plate, a central bending post and a standing plate affixed to the central post; the standing plate exerts tension upon the central post particularly when a person stands on the plate; strain gauges are affixed to the central post and the stand as a whole is improved by providing a pair of foot plates placed side by side, each foot plate is supported by a pair of rotatable tubular elements or rings on the stand plate, for elevationally adjustably mounting the respective foot plate; all these elements are driven in unison by a belt such that one foot plate is raised while the other one is lowered and vice versa.

Abstract: A process for diagnosing suspected muscle problems in a subject, comprises observing the difference in temperature between opposite limbs of the subject while one is at rest and the other is exercised. Analysis of the, say, plot of the difference allows a physician to assess immediately whether the subject is, for example, magnesium-deficient, and to prescribe accordingly.

Abstract: A method of measuring the oxidative metabolism of ocular tissue. The ocular tissue is alternately illuminated, with light of a sample wavelength corresponding to the absorption peak of cytochrome a,a.sub.3 and light of a reference slightly above or below the sample wavelength. Light reflected by the ocular tissue is detected and an electronic signal corresponding to said light produced. The signal corresponding to the reference wavelength is subtracted from the produced signal. In a preferred embodiment an optical probe with a first probe to deliver light to the ocular tissue and a second probe to deliver reflected light to a detector is provided. The optical probe is placed on the ocular tissue under study.

Abstract: The nocturnal penile tumescene and rigidity sensor device includes a flexible, foldable member that supports a relatively soft foam material and a relatively hard foam material. In one embodiment of the invention the relatively soft foam material and the relatively hard foam material cooperate with corresponding force-sensing resistors to detect changes in penile tumescence and rigidity. The relatively soft foam material detects changes in penile tumescence whereas the relatively hard foam material and its corresponding force-sensing resistor detect the presence and/or changes in penile rigidity. In another embodiment of the invention, a relatively soft foam material and a relatively hard foam material, formed of conductive foams, are shaped to contact a conductive strip with preselected different areas of surface contact in response to different levels of tumescence and rigidity. The change of contact area between the conductive foams and the conductive strip is detected and recorded.

Abstract: Under the present invention, a method and apparatus are provided for compensating for the effect temperature variations have on the wavelength of light emitted by the oximeter sensor light sources (40, 42). In pulse oximetry, LEDs are typically employed to expose tissue to light at two different wavelengths. The light illuminating the tissue is received by a detector (38) where signals proportional to the intensity of light are produced. These signals are then processed by the oximeter circuitry to produce an indication of oxygen saturation. Because current oximetry techniques are dependent upon the wavelengths of light emitted by the LEDs (40-42), the wavelengths must be known. Even when predetermined combinations of LEDs (40-42) having relatively precise wavelengths are employed, variations in the wavelength of light emitted may result. Because the sensor (12) may be exposed to a significant range of temperatures while in use, the effect of temperature on the wavelengths may be significant.