Abstract: An apparatus and method for a ventilator system which may be operated over a high range of frequencies from zero (0) to fifty (50) hertz as may be predetermined. A high frequency oscillator (14) has a pneumatically operated piston drive device (16) which may be operated at a predetermined frequency, a predetermined stroke length, and at a predetermined ratio between the time periods for the pressure stroke and the suction stroke. The piston (76) is operated from a plurality of solenoid operated valves (91). A microprocessor (92) controls the electronic operation of the valves (91) by suitable output signals.

Abstract: The improved snorkel includes a conduit divided approximately mid-length by a first purge valve. The first purge valve is located adjacent and above the water surface when the snorkel is in use by a skin diver swimming face down on the water surface. The first purge valve opens under slight hydrostatic pressure and quickly drains water from the upper portion of the conduit when the skin diver returns to the surface after swimming or diving underwater. The lower portion of the conduit is purged for respiration by exhaling a forceful blast of air into the mouthpiece which pushes the water upward. The effort required to purge the improved snorkel is reduced because the bulk of the ascending water flows out the first purge valve, without the need to overflow the snorkel top. A chamber located below the mouthpiece captures residual water in the snorkel after a purging exhalation and water which overflows the first purge valve after splashing in the open end.

Abstract: An ophthalmological diagnosis method and an apparatus for carrying out the method is disclosed. According to the invention, one of a plurality of laser beams is selected depending upon the tissue layers in the eye fundus to be diagnosed, and is projected thereon. Light is scattered by blood cells within a tissue layer of the eye fundus that depends upon the wavelength of the selected laser beam. The scattered light is received and photoelectrically converted into an electrical signal, which is then evaluated to measure the blood flow state within the tissue layer of the eye fundus.

Abstract: An electrical transdermal drug applicator provides enhanced drug flow to the bloodstream of the subject by delivering a primary drug into a subject's circulatory system for therapeutic purposes, and delivering from the same or other reservoir a non-therapeutic counteracting agent to the skin of the patient which induces flow enhancement and allows delivery of the primary drug systemically over a longer period of time and in greater quantity than heretofore appeared possible using electric current.

Abstract: A magnetically shielded enclosure provides a shielded environment having very low, constant levels of magnetic and electrical signals resulting from external sources, so that the magnetic signals produced by the body of a person in the enclosure can be measured in the absence of outside interference. The walls of the enclosure include concentric layers of a superconducting material and a material that is electrically and thermally conductive, and the person and magnetic measurement apparatus are enclosed therein. The superconducting layer is preferably supported on, and in thermal contact with, the conductive layer, and is cooled to a temperature below its superconducting transition temperature by cooling the conductive layer. Optionally, a magnetic cancellation field is applied prior to transforming the superconducting material to the superconducting state or otherwise sealing the enclosure, to zero the internal magnetic field.

Abstract: An eye pressure meter provided with a pressing system for deforming the cornea of an eye to be examined, a detecting system for detecting the speed of deformation of the cornea, and a calculating system for calculating eye pressure value information on the basis of the information of the speed of deformation.

Abstract: An allergy testing system, for testing a patient for a plurality of allergies at substantially the same time, comprises a housing containing a plurality of packages or capsules containing an allergen and a needle, the needles being spaced apart from each other. The needles preferably carry the respective allergies on their tips. The housing is placed against the skin of a patient and an actuator is operated to engage the packages to move the needles to pierce or prick the skin of the patient, thereby applying the respective allergens to the pierced or pricked skin of the patient.

Abstract: A portable unobtrusive device to be used in combination with an imagescope. The portable device features a pair of eyeglasses having a circuit for monitoring a physiological function of the eyeglass wearer corresponding to a predetermined stress level. The circuit contains an alarm which emits an auditory and/or visual signal in response to a change in said physiological function.

Abstract: A stopper for medical containers such as blood collection tubes having integral flange and plug portions, the flange portion being substantially larger in diameter than the plug portion, which plug portion is sized to sealably close the container. The stopper has opposed wells formed in the flange and plug portions, the well in the flange portion having a relatively flat bottom surface at least as large in diameter as the diameter of the opposed well in the plug portion. The flange portion is constructed to be guided into a tube holder into which it is inserted such that one end of a needle projecting into the interior of the tube holder will penetrate the stopper in the area of the opposed wells so as to avoid otherwise contacting the stopper. The enlarged flange portion also serves to facilitate removal of the stopper from the container without contaminating a handler.

Abstract: The invention concerns a filter container for an absorption filter (8) and a particle filter (7), the container being adapted to be connected to a protective mask.

Abstract: An inhalation sensor which uses a non-metallic diaphragm that is metallized on one side, pre-stressed, and used as one plate of a variable capacitance pressure tranducer to sense the inhalation and exhalation of air from the nostrils and/or mouth of a patient. The inhalation sensor is used for inhalation therapy by triggering a prescribed dose of therapeutic gas when inhalation takes place. The inhalation sensor can also be used as a monitor to detect apnea (the absence of breathing).

Abstract: A medication infusion system may be selectively configured to perform an emulation of any one of a plurality of Device Types corresponding to the environment of use. The particular parameters which relate to a given Device Type are set into the system either at the factory or by biomedical engineers at the hospital or other medical institution by resort to an intercoupled computer driven by appropriate software. With the system set up in this fashion, a clinical user can select a given Device Type and can view but cannot change the critical operating parameters thereof. Substantial economies and improvement of device operation are realized by the provision of one switchable system in place of the plurality of different types of devices now required in a given institution.

Abstract: In a brain wave detecting system, in one embodiment, a flexible hat is placed on the head of the patient. The hat contains a plurality of electrodes conforming to the hat. A circuit board having a low-noise integrated circuit amplifier may be mounted thereon. Each electrode uses a plurality of metal conductive fingers which protrude through the hair to the scalp and provide multi-contact sites on the scalp for each electrode. The tips of each electrode contact the user's scalp to provide a redundancy of contacts for each electrode.

Abstract: The invention relates to a method and an apparatus for controlling the cuff pressure in a sphygmomanometer. The pressure control mechanism for a cuff (3) consists of one or a plurality of valves (4) whose operation is controlled by a control element (5) in a manner that the pulse frequency of valve (4) or valves (4) exceeds that of the heart. By using a pulse-controlled high-speed so-called on-off valve it is possible to effect the cuff pressure drop in a completely linear fashion by opening and closing the valve at a necessary frequency and by adjusting the durations of the on- and off-periods of said valve or valves.

Abstract: An apparatus and method for transmitting prosthetic information to the brain contains an array of sensory elements that receive energy from an external stimulus and process those signals via neural filters and neural waveforms to produce a pulse or `spike` train that is temporally encoded with information that is functionally related to the external stimulus. The simulated spike trains, when applied to an appropriate area of the brain, produce perceptions that are functionally related to the sensed external stimuli so that a subject can discriminate between different spike trains representative of different external stimuli.

Abstract: A method for carrying out hemodynamic measurements on a patient, using a low-directed balloon catheter, which is connected to a measuring unit and is at least provided with a distal measuring lumen and a balloon-inflating lumen, comprising the steps of inserting the catheter by way of a suitable vein and further by way of the right atrium and ventricle into the pulmonary artery until the distal end with the inflated balloon in wedge position is stuck in a branch thereof and closes off the latter. A proximal measuring lumen is provided a few centimeters apart from the distal measuring lumen. Then the pulmonary arterial pressure (PAP) is measured, as long as the catheter has not yet arrived in the wedge position, via both the proximal and distal measuring lumina and the two relevant, virtually identical pressure curves are simultaneously recorded.

Abstract: The instrumentation of sizes of a retinal vessel in the fundus is carried out by measuring continuously the sizes of the retinal vessel changing in accordance with heart beats at a site preset on the arteriole or the venule of the retinal vessel from images of the retinal vessel in the fundus continuously taken by a television camera or other photographic means; and comparing a periodical change of the sizes of the arteriole or venule of the retinal vessel. Static images are extracted at a given interval from fundus images photographed continuously by a television camera or recorded in a video tape recorder and converted into digital image which, in turn, is subjected to image processing. A length of the processed image data is measured at a given site of the image data fetched at a given timing from a storage, and a graph of rectangular coordinates is formed with a time coordinate versus a coordinate of measured values.

Abstract: A flexible endotracheal tube is disclosed for acoustically monitoring the heart sounds of a patient. The tube comprises a flexible conduit to provide a respiratory passage and a separate cardiac sound passage conduit. An inflatable cuff is disposed near the distal end of the flexible conduit to contact and sealingly conform to the interior wall of the trachea upon inflation. The closed chamber of the inflatable cuff is in fluid communication with the separate sound passage for enhanced acoustic reception from the inflatable cuff. The distal end of the sound passage conduit includes a terminal end defining an angular cut to enhance the acoustic reception of the heart sounds acoustically transmitted from the interior tracheal wall through the inflatable cuff and into the acoustically separate conduit.

Abstract: A system for determining if a blood pressure measurement made by an automatic blood pressure monitor has been adversely affected by artifact. The system first compares the diastolic, mean arterial and systolic pressures to respective average diastolic, mean arterial and systolic pressures. If all three of these pressures are within a predetermined range of their corresponding average pressures and if the relationship between these pressures conforms to a physiologically realistic model, then the diastolic, mean arterial and systolic pressures obtained from a measurement are considered valid. If more than one of these pressures is outside the predetermined range of its corresponding average pressure, then the measurement is considered to be adversely affected by artifact and is rejected. If only one of these pressures is outside the predetermined range of its corresponding average pressure, then a replacement pressure is calculated for that pressure.

Abstract: Tympanic temperature measurements are obtained from the output of a thermopile mounted in an extension from a housing. The housing has a temperature display thereon and supports the electronics for responding to sensed radiation. The thermopile is mounted in a highly conductive can which includes a radiation guide and thermal mass. The guide provides a narrow field of view due to a fairly high emissivity. Electronics determine the target temperature as a function of the temperature of the hot junction of the thermopile determined from the cold junction temperature and a thermopile coefficient. The tympanic temperature is adjusted to provide an indication of core temperature.