The Chiari III malformation: an unusual and asymptomatic variant in an 11-year old child.

Chiari III malformation is an extremely rare condition, and is characterized by the hindbrain herniation into a low occipital or high cervical encephalocele together with the pathologic and imaging features of the Chiari II malformation. In this report, an unusual variant of the Chiari III malformation was diagnosed in an 11-year-old girl. She had an encephalocele operation when she was a newborn, and has been asymptomatic since then. The clinical and imaging findings of this case were presented.