Spontaneous intracranial hypotension presenting as a reversible dorsal midbrain syndrome.

A 47-year-old woman with postural headache, episodic stupor, and vertical gaze palsy had brain imaging findings consistent with spontaneous intracranial hypotension (SIH), including severe descent of the mesodiencephalic structures and diffuse pachymeningeal enhancement. The source of the cerebrospinal fluid leakage was a ruptured dorsal perineural cyst. Clinical symptoms improved after a targeted epidural blood patch was performed. Dorsal midbrain syndrome has not been reported previously as a manifestation of SIH. Perhaps distortion of structures in this brain region can occur in SIH as it does in obstructive hydrocephalus.