Background

Spontaneous intracranial hypotension typically results from a spontaneous cerebrospinal fluid (CSF) leak.1 ,2 Symptoms include orthostatic headache and meningism without a recent dural puncture,2 and may be associated with distant and trivial trauma.3 The diagnosis may be made clinically by the typical headache and supported by pachymeningeal enhancement on MR scan or a low CSF pressure at lumbar puncture.2 If severe and continued, the low pressure can have serious complications, including brain sagging with subdural hygromas,4 cerebral venous sinus thrombosis,5 subdural haematoma2 and subarachnoid haemorrhage.6 Indicators of a serious complication include cranial nerve palsy and worsening mental status, progressing to coma.4 Herniation can result from a pressure differential, with spinal intrathecal pressure lower than intracranial pressure. Left untreated, this can result in significant morbidity or death.

Treatment may be conservative, involving strict bed rest, use of the Trendelenburg position, intravenous/oral hydration and caffeine. If these measures fail, an epidural blood patch, starting ‘blindly’ in the lumbar region, may help.7 People with persistent symptoms need imaging with a radionuclide scan or CT/MR myelography to help localise the CSF leak, followed by a targeted epidural blood patch or surgical repair.3 ,7 Intrathecal saline infusion has succeeded in treating otherwise refractory spontaneous intracranial hypotension.8–12

We report a case of spontaneous intracranial hypotension complicated by bilateral subdural hygromas and subdural haematomas, with uncal herniation, coma and bilateral posterior cerebral artery infarctions. We treated her with an intrathecal saline infusion under pressure monitoring, with rapid resolution of coma.