Journal of Ultrasound in Medicine, Vol 10, Issue 3 121-124, Copyright © 1991 by American Institute of Ultrasound in Medicine
Effect of measurement errors on sonographic evaluation of ventriculomegaly
J. Heiserman, R. A. Filly and R. B. Goldstein
Department of Radiology, University of California School of Medicine, San Francisco 94143.
Ventriculomegaly is a sensitive indicator of maldevelopment of the fetal
brain and spinal cord. The fetal ventricular atrium is an optimal portion
of the lateral ventricular system to measure in order to judge
ventriculomegaly. We tested the susceptibility of this measurement to
inaccuracies created by errors in cursor placement or improper selection of
the plane of section for measurement in 52 normal fetuses. This measurement
was shown to be reasonably insensitive to errors in cursor placement along
the axis of the ventricular system. However, choice of an off-axis image
plane of section, an angled measurement, or improper choice of ventricular
boundary leads to a relatively large number of false-positive test results
(approximately 10%). None of the simulated errors in atrial measurements
underestimates the size of the ventricle, and thus, they are unlikely to
result in a diminution of test sensitivity.
