RESUMO
Hydranencephaly is a rare severe abnormality characterized by replacement of cerebral hemisphere with fluid covered by leptomeninges such that absent cerebral cortex. We present the Ultrasonographic diagnosis of a case of fetal Hydranencephaly at 38 weeks of gestation. Sonography revealed the absence of cerebral cortex, thalami and basal ganglia with disrupted falx and preserved posterior fossa structures. This was the first reported case of Hydranencephaly with absence thalami and basal ganglia along with midbrain. Confirmation of diagnosis was made with postnatal computed tomography. Even though it was diagnosed in the late third trimester, it allowed prompt and finest obstetric management which reduced the risk for both fetus and mother. Furthermore it allowed arrangement of optimal conditions for birth at a unit with accessible specialized pediatric facilities.