RESUMO
OBJECTIVE: The objective of this article is to describe the diagnostic significance of prenatal identification of dilated supra-pineal recess (SPR) in cases of ventriculomegaly. METHOD: A retrospective study, based on neurosonography and magnetic resonance imaging, of a series of five prenatal cases referred to our institution because of ventriculomegaly associated with dilatation of the SPR. RESULTS: Ventriculomegaly of obstructive origin was diagnosed in all cases and related to obstruction downstream of the third ventricle. The diagnosis in the five prenatal cases, confirmed on early post-natal imaging, included the following: malformative aqueductal stenosis, ischemic-haemorrhagic parenchymal supra-tentorial insult complicated by aqueductal stenosis, Blake's pouch cyst, cystic lesion of the posterior fossa and sub-ependymal haemorrhage and Dandy-Walker malformation. In all cases, the third ventricle was prominent and associated with a dilated SPR. In two cases, the dilatation of the SPR was an early clue to e obstructive ventriculomegaly, which was initially minor and became severe on follow-up imaging. CONCLUSION: The presence of a dilated SPR prenatally in the presence of even mild ventriculomegaly should prompt evaluation and follow-up for the presence of obstructive ventriculomegaly with obstruction located downstream of the third ventricle.