Ventricular volume measurement from a multiplanar transesophageal ultrasonic imaging system: an in vitro study.
We have developed a system to assess the feasibility of using multiple transesophageal ultrasonic images to measure left-ventricular volume, an important variable in patient management. The system includes a special transesophageal probe with a micromanipulator for acquiring cardiac images in multiple planes with known interplanar spatial relationship and an off-line processing system to compute the volume. In vitro studies with the probe demonstrated that the distance between two targets in space can be identified within 2 mm (SD = 0.4 mm) for points in the imaging plane 3.4 mm (SD = 0.5 mm) for points not lying in the imaging plane. This gives an average accuracy of +/- 6.5% for distances greater than 4.5 cm. Comparison of ultrasonic measurements of the volume of water-filled balloons and excised hearts to the volume required to fill them, revealed a correlation coefficient of 0.992, a regression line having a slope of 1.0 and an ordinate intercept at 0.2 mL, and a standard error of the estimate of 8 mL.
Martin
R W
RW
Department of Anesthesiology, University of Washington, Seattle 98195.
Bashein
G
G
Detmer
P R
PR
Moritz
W E
WE
D002138:Calibration; D004947:Esophagus; D006801:Humans; D007091:Image Processing, Computer-Assisted; D013318:Stroke Volume; D014463:Ultrasonography / Q000379:methods*