| abstract |
Apparatus and method comprising an ultrasound transmitter, for placement at a first location on the body of a subject, to emit an ultrasound pulse; an ultrasound receiver, for placement at a second location on the body, to detect an emitted ultrasound pulse; and a controller in communication with the transmitter and receiver. The controller causes an ultrasound pulse to be emitted by the transmitter; receives a measurement signal from the receiver; determines, based on the received measurement signal, a time of arrival at the receiver, T 1 s of a first part of the emitted ultrasound pulse; determines, based on the received measurement signal, a time of arrival at the receiver, T 2 , of a second part of the ultrasound pulse; and calculates, using T 1 and T 2 , a flow velocity of blood in a blood vessel between the first location and the second location. |