Case report

A healthy 30-year-old gravida was referred for second level ultrasound scan at 20 weeks of gestation.
Previous personal, familial and obstetrical history was non relevant.
Following images revealed an enlarged-white cerebellum and vermian agnesis. A MRI was done at 20 weeks of pregnancy. The confirmed diagnosis was rhombencephalosynapsis.

Images 1-3; video 1: 2D images of the fetal head in transverse view absent vermis, echogenic cerebellum without normal clefting between the cerebellar hemispheres, single-lobed cerebellum.

Image 4: MRI T2 axial image supports the ultrasound findings and confirmed the suspected diagnosis of rhombencephalosynapsis.