Posterior fossa subdural hematoma in spontaneous intracranial hypotension.

Spontaneous intracranial hypotension (SIH) is associated with subdural hematoma in the supratentorial convexities. We report a patient with SIH who had presented to us with subdural hematoma in the posterior fossa. A 50 year old lady presented with history of sudden onset of lower back ache of 4 weeks duration and daily headaches and neck pain for past three weeks. The headache exacerbated on activity, on sitting and standing position and relieved on supine position. There was no history of fever or head trauma. Imaging of the brain revealed hematoma of the tentorium cerebelli, hematoma of the bilateral convexities in addition to other signs of spontaneous intracranial hypotension. She was administered epidural patch with there was complete resolution of symptoms. Subdural hematoma is seen in upto 20 % of patients with SIH. Treatment of the CSF leak is generally sufficient for management of the subdural hematoma and for preventing its recurrence. Decompression craniectomy is reserved for hematomas larger than 10 mm on CT scan or associated impaired consciousness. In these patients, delay in evacuating SDH might be associated with an increased risk of brain herniation. Subdural hematoma in the posterior fossa is rare and has been reported following trauma. It has never been reported in spontaneous intracranial hypotension. This report illustrates SIH as a rare etiology of posterior fossa subdural hematoma. Posterior fossa hematoma in the absence of trauma should raise the suspicion of SIH and one should carefully look for features of CSF leak on imaging.