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Biomedical subjects

P A Magnin

Publications and source records attributed to P A Magnin.

3 recordsLinked to original sources
PubMed1984

A-mode speckle reduction with compound frequencies and compound bandwidths.

A simple model for predicting the degree of speckle reduction in A-mode images via the correlation coefficient was tested experimentally. The model appeared to account correctly for the influence of image system bandwidth on frequency separations required for nearly independent sampling in compound frequency imaging. Moreover, the notion of compound bandwidth imaging was tested; the correlation between samples at different bandwidths decreased as the ratio of bandwidths decreased.

Humans↗
PubMed1981

Combined doppler and phased-array echocardiographic estimation of cardiac output.

The capability of a pulsed Doppler flowmeter combined with a phased-array imaging system to measure volume flow was tested in vitro and in patients undergoing cardiac catheterization. The Doppler-phased-array system (DPA) was used to determine vessel diameter and a superimposed cursor was used to locate the range and angle of the Doppler sample volume. DPA estimates of continuous flow through tubing in a water tank correlated strongly (r = 0.99) with measured flow corresponding to physiologic ranges from 3-12 l/min. For pulsatile flow in a water tank, a correlation of r = 0.86 with measured flow was obtained, whereas DPA estimates of cardiac outputs compared with Fick estimates in the 11 patients produced a correlation of r = 0.83. These data indicate that estimates of cardiac output are possible using the DPA approach.

Adult↗