[Spontaneous intracranial hypotension syndrome. Clinical, neuroradiological and cerebrospinal fluid findings].

We report 11 patients with orthostatic headache due to spontaneous intracranial hypotension. Nausea (3 patients) and abducens palsy (2 patients) were the main additional symptoms. Ten patients had CSF pleocytosis (6 to 43 white cells/microliter) and/or increased protein (581 to 1668 mg/l). CT and/or MRI documented bifrontal accentuated subdural hygromas and hematomas in 5 patients. MRI also documented diffuse meningeal gadolinium enhancement in all 4 patients examined, and descent of the brain in one. Cisternography was done in 9 patients and revealed a decreased or absent activity over the convexities and early detection of the tracer in the bladder in all, and a CSF leak at the cervicothoracal junction in 2 patients. Most patients improved with bed rest, increased fluid intake (oral or intravenous), steroids, and/or epidural blood patch. Subdural hematomas increased in 2 patients and have to be drained. Spontaneous intracranial hypotension is due to a CSF leak followed by decreased CSF volume and hydrostatic CSF pressure changes. The locations of the leaks are mainly cervical or at the cervicothoracal junction. MRI always documents diffuse meningeal gadolinium enhancement. Treatment of choice is an epidural blood patch. Surgical treatment may be needed in patients with subdural hematomas or meningeal diverticula. Prognosis is typically good, but subdural hematomas may occasionally lead to an increased intracranial pressure.