Reliability of continuous-wave Doppler probes.

Small-diameter, thin-walled latex tubes, through which a blood-simulating agent (0.1% suspension of simethicone in 0.9% sodium chloride) flowed at controlled rates, were embedded at varying depths in a tissue-mimicking matrix of powered graphite suspended in 4% agar.

Transcutaneous quantitation of arterial flow with ultrasound.

Arterial blood flow was measured in dogs simultaneously with electromagnetic flow probes and with ultrasonic "flow probes." The ultrasonic probes were used to determine transcutaneously the mean velocity of arterial flow and the cross-sectional area of the blood vessel. A 10 MHz probe was used for blood vessels 1 cm deep or less, while a 5 MHz probe was used for vessels between 1.

Use of combined oculoplethysmography, carotid phonoangiography and Doppler in the non-invasive diagnosis of extracranial carotid occlusive disease.

One hundred and eight patients were studied with fluid-filled oculoplethysmography and carotid phonoangiography (OPG-CPA) and by arteriography. Thirty-two patients also had "Doppler evaluation" of supraorbital arterial flow. The OPG-CPA correctly predicted the degree of occlusion in 76% of the involved vessels, including the degree of occlusion of each carotid for each patient (63%).

Noninvasive determination of LeVeen shunt patency.

The LeVeen peritoneovenous shunt is being used with increasing frequency for management of intractable ascites. The question of postoperative shunt patency frequently arises. This report describes a unique, noninvasive method of assessing shunt patency using Doppler ultrasound.