Spontaneous Intracranial Hypotension - A Dilemma.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is a highly misdiagnosed and underdiagnosed disorder. OBJECTIVE: Update evaluation and treatment of spontaneous intracranial hypotension. METHODS AND MATERIAL: Narrative review. RESULTS: Traditionally, SIH is diagnosed when a headache has developed spontaneously and in temporal relation to a CSF leak (evident on imaging) and/or CSF hypotension (lumbar puncture opening pressure <60 mm CSF). However, lumbar puncture is not mandatorily required to diagnose SIH. Besides headache, other symptoms such as nausea/vomiting in 50.6%, neck pain/stiffness in 33%, tinnitus in 19%, dizziness in 14%, hearing disturbances in 10.7%, followed by visual disturbances, vertigo, back pain, and cognitive symptoms may be present. In suspected cases of SIH, brain and spine should be evaluated with MRI. Dynamic computerized tomographic myelography is required to demonstrate the site of spinal CSF leak. Epidural blood patch (EBP) is a minimally invasive treatment for spontaneous intracranial hypotension (SIH) refractory to medical management and provides symptomatic relief in up to 90% of patients even in patients with bilateral subdural hematomas. The CSF-venous fistulas do not respond well to EBP, and the most definitive curative treatment is the surgical closure of the fistula. CONCLUSIONS: The SIH is a distinct entity and requires a high index of suspicion for diagnosis. A post-contrast MRI should be included for evaluation of headaches. Spinal MRI should be done to demonstrate the site of leak. Epidural blood patch therapy is the most effective treatment of SIH. Most SDHs associated with SIH do not require treatment.