Patients with the Arnold Chiari Type II malformation may present with signs and symptoms of acute or subacute brainstem and/or upper cervical cord compression. Surgical intervention for Arnold Chiari Type II malformation necessitates making room for the brain as it changes position.

Hydrocephalus in myelomeningocele is related to the Arnold Chiari Type II malformation. This condition may cause acute or subacute signs and symptoms of brainstem compression, including, swallowing difficulty, respiratory stridor, and upper extremity weakness. Surgical decompression of the brainstem and upper spinal region may be indicated (Purdy, 1993).