Abstract: Methods and systems are described for detecting the likelihood of patent ductus arteriosus (PDA) in an infant using electrocardiogram and photoplethysmographic pulse signals obtained from the upper body and foot of the infant.

Abstract: Methods and systems are described for detecting the likelihood of patent ductus arteriosus (PDA) in an infant using electrocardiogram and photoplethysmographic pulse signals obtained from the upper body and foot of the infant.

Abstract: Methods and systems are described for detecting the likelihood of patent ductus arteriosus (PDA) in an infant using electrocardiogram and photoplethysmographic pulse signals obtained from the upper body and foot of the infant.

Abstract: A method for the measurement of oxygenation level of blood in a tissue. The method includes emitting on a tissue light having a wavelength range in which oxygenated hemoglobin has a first extinction coefficient and de-oxygenated hemoglobin has a second extinction coefficient, and wherein one of the first and second extinction coefficients changes monotonically as a function of wavelength while the other one of the first and second extinction coefficients is substantially constant with respect to the one of the first and second extinction coefficients. The method further includes detecting a transmitted spectrum of light transmitted through the tissue, measuring a differentiating parameter expressing a change in at least one parameter of the emitted spectrum with respect to same parameter in the transmitted spectrum, and determining an oxygenation level of blood in the tissue, wherein the oxygenation level corresponds to a value of the measured differentiating parameter.

Abstract: Techniques for determining average value of an arterial blood pressure parameter of an examined subject are disclosed. A pressure device is used to apply changing pressure conditions over a body part of a subject and generate pressure measurement data indicative of the pressure applied. A first measuring unit measures blood-pressure-pulse related signals in the pressure-affected body part, and generate blood-pressure-pulse related measurement data indicative thereof, and a second measuring unit measures blood-pressure-pulse related signals in a pressure-free body part of the examined subject, and generate reference blood-pressure-pulse related measurement data indicative thereof.

Abstract: Methods and systems are described for detecting the likelihood of patent ductus arteriosus (PDA) in an infant using electrocardiogram and photoplethysmographic pulse signals obtained from the upper body and foot of the infant.

Abstract: Methods and systems are described for detecting the likelihood of patent ductus arteriosus (PDA) in an infant using electrocardiogram and photoplethysmographic pulse signals obtained from the upper body and foot of the infant.

Abstract: Methods and systems are described for detecting the likelihood of an aortic coarctation in an infant using photoplethysmographic pulse signals obtained from the hand and foot of the infant.

Abstract: Techniques for determining average value of an arterial blood pressure parameter of an examined subject are disclosed. A pressure device is used to apply changing pressure conditions over a body part of a subject and generate pressure measurement data indicative of the pressure applied. A first measuring unit measures blood-pressure-pulse related signals in the pressure-affected body part, and generate blood-pressure-pulse related measurement data indicative thereof, and a second measuring unit measures blood-pressure-pulse related signals in a pressure-free body part of the examined subject, and generate reference blood-pressure-pulse related measurement data indicative thereof.

Abstract: Methods and systems are described for detecting the likelihood of an aortic coarctation in an infant using photoplethysmographic pulse signals obtained from the hand and foot of the infant.

Abstract: Systolic blood pressure of a subject is determined by application of monotonic changing pressure conditions over a region of an organ of the subject, simultaneous illumination of a tissue in the pressurized organ with light and measurement of optical data indicative of passage of the light through the tissue and of pressure data indicative of the pressure being applied over said region of said organ. At least one pulsatile and at least one baseline component are determined from the measured optical data and changes are then identified in each of the components, said changes indicative that the pressure applied over the organ is smaller than systolic blood pressure of the subject. The systolic blood pressure of the subject may be determined as a maximal applied pressure at which at least one of the changes in the pulsatile component and the changes in the baseline component started to appear.

Abstract: A method for obtaining diagnostic information relating to the lungs of a subject includes directing into tissue of the lungs of the subject light of a first wavelength and detecting part of the light that has passed primarily through microcirculatory tissue of the lungs and generating a signal which is a function of intensity of the detected light. The signal is then processed to derive a PPG curve for pulmonary microcirculatory arteries. The method is implemented using various locations for a light source and a detector, including various combinations of positioning on the thoracic wall, insertion into the esophagus, and in some cases, insertion of a probe through the thoracic wall to a position adjacent to the pulmonary pleura. Use of two different wavelengths allows derivation of mixed venous blood oxygen saturation.

Abstract: The present invention relates to cuff-based method for the measurement of systolic blood pressure (SBP) by measuring photoplethysmographic (PPG) signals in peripheral blood vessels distal to the cuff and to a method for cuffless measurement of SBP by analyzing PPG signals in peripheral blood vessels, after suitable calibration by the cuff-based PPG method for the measurement of SBP.

Abstract: A method for the measurement of oxygen saturation in arterial blood SaO2 by means of pulse oximetry without calibration is described. Photoplethysmography (PPG) is measured in three wavelengths in the infrared and for each PPG curve the relative change in light transmission is obtained. Two equations, each relating SaO2 to the ratio of the relative changes in light transmission for two wavelengths, using the values of the extinction coefficients of oxygenated and deoxygenated hemoglobin for the three wavelengths, enable the determination of SaO2, assuming linear dependence of the optical path-length on the wavelength, for the three wavelengths in the infrared.

Abstract: The present invention relates to cuff-based method for the measurement of systolic blood pressure (SBP) by measuring photoplethysmographic (PPG) signals in peripheral blood vessels distal to the cuff and to a method for cuffless measurement of SBP by analyzing PPG signals in peripheral blood vessels, after suitable calibration by the cuff-based PPG method for the measurement of SBP.

Abstract: A method for measuring arterial diastolic blood pressure in a subject includes deriving values of a delay between pulses in two signals indicative of cardiac induced pulsatile variations of a cardiovascular parameter in a first region and a second region of the subject's body. A variable pressure applied to a region of the subject's body causes variation of the delay. A difference curve is calculated by subtracting from the delay values a monotonic mathematical function adjusted as a best-fit to the data. A value of the variable pressure for which the difference curve exhibits a stationary point is then identified as the diastolic blood pressure.

Abstract: A method for measuring systolic blood pressure includes raising the cuff pressure in such a manner that two conditions are satisfied: (1) The cuff air pressure takes sufficient time to reach the SBP value to avoid blood pressure in the arteries under the PPG sensor being too low, thereby avoiding collapse of the arterioles under the PPG sensor; and (2) The increase of the cuff air pressure between the DBP value and the SBP value is not overly slow in a manner which would cause a relatively high mean blood pressure in the arteries distal to the cuff, and could lead to reduced sensitivity in detecting the restart of blood flow when the cuff air pressure decreases to just below SBP value.

Abstract: A method of measurement of arterial diastolic blood pressure includes generating first and second signals indicative, respectively, of cardiac induced pulsatile variations in tissue blood volume in a first region and a second region of the subject's body. These signals are then processed to derive values of a delay between pulses in the first signal and corresponding pulses in second signal. A baseline value of the delay is evaluated, preferably in the absence of externally applied pressure. A variable pressure is applied to a third region of the subject's body so as to affect blood flow through at least one artery in the third region, the variable pressure being varied as a function of time. The first, second and third regions of the subject's body are chosen such that the delay varies as a function of the variable pressure. The diastolic pressure is then identified as a value of the variable pressure corresponding to a predefined non-zero value of the delay measured relative to the baseline value.

Abstract: Apparatus for measuring the variability of cardiovascular parameters, having a photoplethysmographic (PPG) probe, including a modulated first light source and a photodetector, a demodulator connected to the photodetector for demodulating PPG signals detected by the photodetector, an analog to digital converter for digitizing the demodulated signals, and a processor for repeatedly analysing the PPG signals for a predetermined number of times. A method for measuring the variability of cardovascular parameters.

Abstract: A head holder for holding the head of a human subject while imparting to it an acceleration. The holder comprises a helmet-like member at least partly surrounding subject's head, which helmet-like member is adapted to be set in motion by drive means and is provided with at least one head-clamping member appliable to selected locations on the subject's head. The head-clamping member is adapted to transfer the accelerating force produced by the drive means to the head. The arrangement being such that an effective component of the accelerating force applied by the head-clamping member to the head via selected locations thereon acts on the skull bone underneath the locations. A method for examining the vestibular system of a human subject is also described.