Spontaneous intracranial hypotension: use of unenhanced MRI.

We report a case of spontaneous intracranial hypotension diagnosed with unenhanced cranial MRI, showing laminar subdural fluid and engorgement of the hypophysis and perisellar sinuses. Cerebrospinal fluid pressure was low. MRI was normal after resolution of symptoms. Prior reports emphasise the enhancing pachymeninges seen in this syndrome. We maintain that, when subdural collections and perisellar engorgement are detected on unenhanced MRI in the proper clinical setting, contrast enhancement may not be necessary for the diagnosis.