Dandy-Walker Syndrome: Delayed Acute Presentation With Unusual Symptoms.

Dandy-Walker syndrome (DWS) is a rare congenital brain malformation defined by the presence of an expanded posterior fossa, full or partial absence of the cerebellar vermis, and a cystic expansion of the fourth ventricle. We report an 18-month-old girl with DWS presenting with atypical clinical manifestations and unusual symptoms. She initially presented with persistent vomiting and abdominal pain for four days, not responding to antiemetic medication. In addition, she was found to have abnormal postural arching of the back, extension of the lower limbs, and neck extension. MRI and CT head suggested Dandy-Walker syndrome with hydrocephalus (the lateral ventricle, third ventricle, and fourth ventricle are all significantly dilated with evidence of trans-ependymal cerebrospinal fluid permeation, severe compression anterior displacement of the brain stem). The patient underwent urgent, lifesaving right sub-occipital craniotomy, evacuation, and decompression of the posterior fossa cyst and external ventricular drain (EVD) insertion along with left supra-tentorial EVD insertion. A series of brain magnetic imaging and CT brain post-procedure studies showed a significant reduction in the size of the ventricular system and mass effect on the brain stem.