Intracranial hypotension without meningeal enhancement on magnetic resonance imaging - Case report

Meningeal enhancement on magnetic resonance (MR) imaging is considered the hallmark radiological feature of intracranial hypotension. The authors repo rt on a patient who exhibited progressively symptomatic intracranial hypote nsion due to a lumbar cerebrospinal fluid (CSF) leak, but in whom MR imagin g demonstrated no pachymeningeal enhancement. This 24-year-old man presented with a 6-week history of progressive orthost atic headaches that were associated with photo- and phonophobia. Four weeks before the onset of the headaches, the patient had undergone a lumbar lami nectomy. Brain MR images revealed subdural fluid collections and brain sagg ing; however, meningeal enhancement was not present. Myelography demonstrat ed a CSF leak at the site of the laminectomy. At surgery, a large dural rea r was repaired. The patient recovered well from the surgery, with complete resolution of his headaches. The absence of meningeal enhancement on MR imaging dacs nor exclude a diagn osis of symptomatic intracranial hypotension.