Journal of Ultrasound in Medicine, Vol 20, Issue 12 1265-1269, Copyright © 2001 by American Institute of Ultrasound in Medicine
Reliability and validity of three-dimensional fetal brain volumes
L. K. Endres and L. Cohen
Department of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois 60611, USA.
OBJECTIVE: To determine the intraobserver and interobserver variability in
calculating three-dimensional fetal brain volumes and to examine the
relationship between these volumes and biparietal diameter and head
circumference measurements and estimated gestational age. METHODS:
Eighty-five subjects between 16 and 40 completed weeks' gestation
participated in the Institutional Review Board-approved study. Fetal head
images were obtained axially and stored on a magnetic optical disk. The
fetal brain volumes were calculated in triplicate by each of 2 observers
using 8 to 10 coronal cuts. The coefficient of variation was determined for
both physicians. Pearson correlations and linear regression were used to
evaluate the relationship between three-dimensional head volume and
standard biparietal diameter and head circumference measurements and
estimated gestational age. RESULTS: The coefficients of variation were low
for both investigators, at 2.04% and 2.44%. The correlations between fetal
brain volumes and biparietal diameter, head circumference, and estimated
gestational age were all highly significant (P < .001). The linear
regression of brain volumes with estimated gestational age was also highly
significant (P < .001). CONCLUSIONS: Three-dimensional fetal brain
volume measurements had excellent intraobserver and interobserver
reliability. The volumes correlated very well with standard biparietal
diameter and head circumference measurements. These volumes can also be
used to determine estimated gestational age.