A method to estimate wall shear rate with a clinical ultrasound scanner.

A simple technique to estimate the wall shear rate in healthy arteries using a clinical ultrasound scanner has been developed. This method uses the theory of fully developed oscillatory flow together with a spectral Doppler trace and an estimate of mean arterial diameter. A method using color flow imaging was compared with the spectral Doppler method in vascular phantoms and found to have errors that were on average 35% greater.

Characterization of an abdominal aortic velocity waveform in patients with abdominal aortic aneurysm.

Haemodynamics studies of abdominal aortic aneurysm require data on the velocity in the normal section of the aorta. Centreline velocity waveforms were measured in abdominal aortic aneurysm patients proximal to the aneurysm using spectral Doppler ultrasound. Characteristic points were automatically found on 21 of the waveforms and their parameters were used to create an archetypal centreline velocity waveform.

B-mode compound imaging in mice.

Cross-sectional B-mode images were obtained from a dead mouse for a 360 degrees scan around the mouse using a 12-MHz linear array. For each cross-section, a set of aligned images was obtained after rotation about the isocenter, which were added to produce a single compound image. The compound images demonstrated a substantial improvement over single B-mode images, with uniform image quality, low noise and improved visualization of structures.