Rhombencephalosynapsis associated with hand anomalies.

A case of rhombencephalosynapsis, a very rare disorder characterized by agenesis or hypogenesis of the cerebellar vermis and fusion of the cerebellar hemispheres, is reported with magnetic resonance imaging features. Radiographs showed anomalies in both hands; namely phalangeal hypoplasia and occult polydactyly in the right hand and syndactyly in the left, previously unreported in association with this disorder.