Spontaneous intracranial hypotension

Abstract

Since the introduction of magnetic resonance imaging (MRI), spontaneous intracranial hypotension has been diagnosed much more frequently. The aim of this review is to discuss the symptoms and signs of the condition, in particular the characteristics of the associated headache, with sudden onset after sitting or standing, so that it can be included under the rubric of ‘thunderclap headache’. This type of headache, like post lumbar puncture headaches, may be caused by cerebral vasodilatation and exacerbated by lowered pressure of the cerebrospinal fluid (CSF). Other symptoms include neck stiffness, nausea, vomiting, vertigo, tinnitus, deafness, and cognitive abnormalities. The clinical picture can sometimes mimic frontotemporal dementia, and the behaviour of some patients can sometimes be described as hypoactive–hypoalert, with somnolence, impaired attention, and stereotyped motor activity. Sagging of the brain, caused by leakeage of the CSF, can cause lesions in the brainstem with stupor, gaze palsies, and cranial nerve palsies. The condition can be a risk factor for cerebral venous thrombosis because of slowing of the blood flow and distortion of the blood vessels. The clinical picture may well suggest the diagnosis, but the headache may possibly indicate a subarachnoid haemorrhage. However, MRI will help to confirm the diagnosis and to localize the site of the CSF leak. MRI myelograms are of particular value, but if they are equivocal a computed tomography myelogram should be performed. The leakage of CSF is due to a tear in the dura, most frequently where the spinal roots leave the subarachnoid space. If this does not heal with bedrest, an epidural blood patch or a percutaneous injection of fibrin glue may be needed. More information is required on long‐term follow‐up.

Thoracic epidural blood patch for spontaneous intracranial hypotension: case report and review of the literature.

“…Several medical treatments have been attempted, such as steroids, intravenous caffeine, acetazolamide, and oral theophylline, but these are controversial (10). Other techniques include percutaneous placement of a fibrin sealant, but in this case the site of leak must be known (7). Intrathecal infusion of saline is a good temporizing method (11), especially if there is a decreased level of consciousness, as was the case with our patient.…”

“…The leak often occurs at the root exit site, and factors for SIH (7). Another theory argues that the disease is due to epidural hypotension maintained by the inferior cava vein outflow to the heart.…”

“…The hallmark feature of SIH is orthostatic headache (7,14). Other symptoms include neck pain and stiffness, nausea, diplopia due to unilateral or bilateral cranial nerve 6 palsy, dizziness, hearing change, tinnitus, confusion, blurred vision, and photophobia (10).…”

Diagnosis and treatment of spontaneous intracranial hypotension due to cerebrospinal fluid leakage

“…The incidence of spontaneous intracranial hypotension is low, with international literature reporting a rate of only 5/10,000 (Gordon 2009). Patients may experience cranial nerve damage, ataxia, increased muscle tone, personality changes, and even disturbance of consciousness.…”

Reversible coma and Duret hemorrhage after intracranial hypotension from remote lumbar spine surgery: case report

“…In spontaneous cases, the CSF leak most commonly results from dural defects along nerve roots. 5,23 Patients with connective tissue disorders may be predisposed to such spontaneous rents. 1,26 Iatrogenic causes of intracranial hypotension include procedures such as spinal anesthesia, lumbar puncture, and spinal surgery.…”