Spontaneous intracranial hypotension in a patient with reversible pachymeningeal enhancement and brain descent.

A 56-year-old woman presented with severe orthostatic headache in association with nausea and vomiting. Lumbar puncture for the patient revealed significantly low cerebrospinal fluid pressure (CSF) and the clinical diagnosis of intracranial hypotension syndrome was made. An initial gadolinium-enhanced brain magnetic resonance imaging (MRI) disclosed diffuse meningeal enhancement as well as brain sagging. No definite CSF leakage was found using radionuclide cisternography. Her headaches abated with proper usage of analgesics, strict bed rest, and intravenous hydration. Follow-up neuroimaging studies showed partially resolved meningeal enhancement 2 months after treatment and complete resolution 6 months after treatment. The temporal changes found on MRI suggest that the pachymeningeal enhancement is reversible in patients with spontaneous intracranial hypotension. Moreover, proliferation of meninges is likely to be responsible for this type of delayed resolution phenomenon.