Abstract
Rhombencephalosynapsis is a hindbrain malformation characterized by complete or partial
absence of the cerebellar vermis, with varying degrees of midline continuity of cerebellar
hemispheres, dentate nuclei, and in some patients of the superior cerebellar peduncles.
Partial rhombencephalosynapsis usually consists of a segmental deficiency of posterior
vermis. Although prenatal diagnosis of rhombencephalosynapsis is feasible by ultrasound
and magnetic resonance imaging both, partial rhombencephalosynapsis might be difficult
to detect, especially at an early gestational age. We report two fetal cases of atypical
partial rhombencephalosynapsis, with deficiency of anterior vermis, detected by prenatal
magnetic resonance imaging at 21st and 23rd week of gestation, respectively.
Keywords
magnetic resonance imaging - prenatal diagnosis - cerebellum - cerebellar vermis -
rhombencephalosynapsis
