Proposed is a Pulse Transit Time, PTT, measurement concept wherein a forced oscillation technique, FOT, is used to determine a pulse arrival time at alveoli of the lungs of a patient.

Provided here are methods of detecting compromised cerebrovascular reactivity in a subject and treating such subject. The method includes acquiring transcranial Doppler signals and cardiac measurements from the subject following a breath-hold maneuver and recording a test set of CBFV measurements. A breath-hold acceleration index is calculated based on a linear regression correlation of temporal variations of the mean velocity across all cardiac cycles during the breath-hold maneuver. The presence of compromised cerebrovascular reactivity in the subject is detected in response to variations in the breath-hold acceleration index of the subject as compared to a healthy individual performing breath-hold maneuver under similar conditions. If the subject has compromised cerebrovascular reactivity, a therapeutically effective compound is administered to the subject along with provision of behavioral modification regimen.

Some implementations of the disclosure describe a blood pressure measurement apparatus and method that enable continuous, non-invasive blood pressure measurement using sound and ultrasound transducers. In one implementation, a blood pressure measurement device includes: a first transducer configured to emit multiple soundwaves having multiple frequencies, the soundwaves configured to cause a blood vessel of a subject to vibrate; a second transducer configured to capture one or more ultrasound images of the blood vessel; and a processing device configured to: determine, based on the one or more ultrasound images, a wall thickness, a radius, and a resonant frequency of the blood vessel; and calculate, based on the wall thickness, the radius, and the resonant frequency, a blood pressure of the subject.

Examples of force sensors that may be incorporated into a number of devices or other objects are disclosed. In one example, a sensor includes a substrate including a first electrode and a second electrode, the first electrode and the second electrode being spaced by an insulating gap, and a compliant material with plural conductive pathways disposed over the gap and contacting the first electrode and the second electrode such that a resistance of an electrical path passing through the compliant material between the first electrode and the second electrode changes in response to force of the compliant material against one or more of the first electrode and the second electrode.

The invention proposes a system for measuring a resonance frequency of a tube. The system comprises: an oscillating unit for oscillating the tube at a plurality of oscillation frequencies, respectively; a detecting unit for detecting a time delay of transmitting a pressure pulse from a first position to a second position in the tube when the tube is oscillated at each oscillation frequency, wherein, when the tube is oscillated at each oscillation frequency in a specific oscillation frequency range of the plurality of oscillation frequencies, the detecting unit detects a variation of the time delay a determining unit for determining a maximal variation of the time delay when the tube is oscillated at the oscillation frequencies in the specific oscillation frequency range; and an indicating unit for indicating an oscillation frequency corresponding to the maximal variation of the time delay, being a resonance frequency of the tube.

An image processing unit includes an image acquisition unit, a blood vessel index value acquisition unit, and a blood vessel parameter calculation unit. The image acquisition unit acquires an endoscopic image captured by an endoscope. The blood vessel index value acquisition unit acquires a first blood vessel index value in a first observation condition and a second blood vessel index value in a second observation condition, as blood vessel index values of blood vessels of an observation target, using the endoscopic image acquired by the image acquisition unit. The blood vessel parameter calculation unit calculates a blood vessel parameter, using the first blood vessel index value and the second blood vessel index value.

According to one embodiment of the present disclosure, a computing device is provided, comprising a processor configured to receive an input. The input includes a first pulse pressure signal obtained using a wearable tonometer affixed to a body of a user. The processor is further configured to apply a transfer function to the first pulse pressure signal, wherein the transfer function converts the first pulse pressure signal into a transformed pulse pressure signal. The transformed pulse pressure signal simulates a second pulse pressure signal of a handheld tonometer concurrently applied to the body of the user.

A biological information imaging method includes a first measurement step to measure an acoustic wave (54) generated by light (53) with which a living body (51) is irradiated from a light source (50) and which is absorbed by tissue (52) in the living body, a storage step to store first information obtained in the first measurement step, a second measurement step to measure an acoustic wave (54) generated by light (53) with which the living body (51) is irradiated from the light source (50) and which is absorbed by the tissue (52) in the living body, and a processing step to generate an image of information of the tissue in the living body by using second information obtained in the second measurement step, and the first information stored in the storage step.

The object of the present invention is to disclose a novel optical miniaturized handheld medical device for convenient monitoring and/or data collection of detailed signals on human cardiovascular function. The implementation consists of a number of advanced technologies, including interferometric detection, phase controlled focusing beam steering, auto-tracking scheme and algorism, and integrated optical chip assembly to enhance the device's performance and miniaturization. Briefly, this handheld medical device directs a single or dual output laser beam(s) onto certain skin surface to detect the surface vibration velocity at the point where the laser hits the surface. The skin surface vibrates in response to cardiovascular signals, such as blood pressure pulses, turbulent blood flow through narrowed arteries, pumping actions of the heart, or the closure of the heart valves etc. The miniaturized apparatus thus is capable of detecting these signals for the assessment of cardiovascular functions in both healthy and disease conditions.

According to some embodiments of the present invention there is provided a method of using an earphone output speaker as a microphone for a phone call between two and/or more participants, or for measuring biometric data of a user. The method may comprise playing a received signal to an electro-acoustic output transducer of an earphone. The method may comprise instructing an audio processing circuit of a local client terminal to record an audio signal from the same electro-acoustic output transducer. The method may comprise calculating a voice signal and/or a biometric measurement based on a function combining the recorded audio signal, the received signal, and filtration coefficients, using a processing unit of the local client terminal. The method may comprise sending the voice signal and/or a biometric measurement through an output interface of the local client terminal.