Cerebellar Abnormalities or Dysgenesis

Rhombencephalosynapsis (RES) is a rare midbrain-hindbrain anomaly characterized by an absence of the cerebellar vermis and fusion of the cerebellar hemispheres and dentate nuclei.

Cerebellar hypoplasia is defined as  a reduction of volume of the cerebellum. It is the hallmark of a heterogeneous group of diseases with various etiologies including developmental and acquired disorders.