Prenatal intracranial hypotension syndrome in congenital cephalocele: Insights into pathophysiologic mechanisms and importance of defect coverage.

Abstract

To compare specific fetal cranial and cerebral findings indicative of prenatal intracranial hypotension (PICH) syndrome between open and closed cephaloceles. Two groups of fetuses with cephalocele who underwent magnetic resonance imaging scan were selected based on the defect coverage: covered ("closed cephalocele" group, n=4) and uncovered by skin ("open cephalocele" group, n=8). The presence of signs associated with PICH syndrome was evaluated and findings compared between groups. Cases from the open cephalocele group showed statistically significant differences in comparison with the closed cephalocele group regarding reduction of the interpeduncular angle (p=0.006), reduced amount of cerebrospinal fluid in the subarachnoid space (p=0.01), collapsed/severely reduced fourth ventricle (p=0.03), cephalocele content (p=0.03), and identification of a vector traction (p=0.03). There were no differences in the presence of cerebellar tonsillar descent, obstructive ventriculomegaly, and presence of the lemon sign. In comparison with gestational age-matched controls, only the biparietal diameter but not the head circumference was significantly smaller in both the open and closed cephalocele groups (p<0.05). Congenital cephaloceles present distinct imaging behavior depending on the defect coverage. Therefore, the classification of cephalocele should include, in addition to location and content, the presence or absence of skin fully covering the defect.