The currently advocated pre-manipulative risk assessment protocols include the use of provocative positional tests to challenge the integrity of the vascular supply to the brain. This paper examines the validity of these pre-manipulative provocative tests in light of recent studies involving ultrasound scanning of the vertebral arteries in subjects who also had provocative tests performed. Thes...

Tricuspid valve regurgitation was assessed quantitatively by measuring blood flow velocity in the vena cava using a pulsed Doppler velocimeter. A non-invasive index of regurgitation was obtained by calculating the ratio between the maximum amplitudes of the systolic and diastolic components of the velocity curves. The index was compared with the angiographic grading of regurgitation in 70 patie...

The analysis of turbulent flow signals irregularly sampled by a Laser Doppler velocimeter is assessed by means of ANNs. This technique has been proven to correctly predict the time evolution of turbulent signals. In this paper we are taking advantage of this ability to obtain models of unevenly sampled signals and thus be able to reconstruct and resample them at a regular pace in order to allow...

This year we celebrate 60 years since Shigeo Satomura published the first measurements of the Doppler shift of ultrasonic signals from a beating heart. He demonstrated that Doppler signals can be retrieved from heart movements when insonated with 3 MHz ultrasonic waves. Later, togheter with Ziro Kaneko, he constructed the first Doppler flowmeter to measure the blood flow velocities in periphera...

Abstract The development of a low-cost Video Velocimeter (VIV) to estimate underwater bulk flow velocity is described. instrument utilizes simplified particle image correlation technique reconstruct an average vector from video recordings ambient particles. VIV uses single camera with set mirrors that splits the view into two stereoscopic views, allowing estimation vector. was validated in cont...