Journal of Ultrasound in Medicine, Vol 6, Issue 6 307-311, Copyright © 1987 by American Institute of Ultrasound in Medicine
A sonographic sign which predicts which fetuses with hydrocephalus have an associated neural tube defect
C. Penso, R. W. Redline and B. R. Benacerraf
We report a sonographic sign which reliably distinguishes those
hydrocephalic fetal heads associated with a neural tube defect from those
which are not, particularly in the second trimester. This sign involves a
"pointed" deformity of the frontal aspect of the skull in fetuses with
hydrocephalus, indicating the presence of a neural tube defect. A
retrospective review of 36 cases of hydrocephalus demonstrates that this
sign is particularly helpful in the second trimester, where it was present
in all the fetuses with hydrocephalus and neural tube defect. It was less
reliable in the third trimester; however, this sign was not present in any
of the fetuses with hydrocephalus who did not have a neural tube defect.
Angulation or pointing of the fetal frontal bone when hydrocephalus is
present, particularly in the second trimester, seems to be a reliable
predictor of an associated neural tube defect and mandates a careful search
for this defect.
