Abnormal prenatal sonographic findings in the posterior cranial fossa: a case of Joubert's syndrome

Joubert's syndrome is a well-documented but rare disorder characterized by a variable combination of central nervous system, respiratory renal and eye anomalies. The most significant and constant neuropathological finding is partial or complete agenesis of the cerebellar vermis. The syndrome was fir st described by Joubert and colleagues as a familial agenesis of the cerebe llar vermis and appears to be inherited as an autosomal recessive trait. A case of Joubert's syndrome is described in which second-trimester ultrasono graphy demonstrated abnormal findings in the fetal posterior fossa with ass ociated renal abnormalities. However, postnatal sonography of the posterior fossa could not confirm the prenatal findings, and the diagnosis of Jouber t's syndrome was only later established by computed tomography of the neona tal brain in the Knowledge of the characteristic clinical picture.