Pathological enlargement of midbrain Virchow-Robin spaces: a rare cause of obstructive hydrocephalus.

Midbrain multiloculated cystic formations can rarely origin by enlargement of Virchow-Robin spaces surrounding mesencephalo-thalamic artery and branches of the collicular and accessory collicular arteries. They can determine several pictures of midbrain syndrome and obstructive hydrocephalus. The authors describe a 38 year-old man affected by a Benedikt's syndrome related to a midbrain multicystic formation. Clinical course, differential diagnosis, and therapeutic choice are here also briefly discussed.