Cerebral sinus venous thrombosis in two patients with spontaneous intracranial hypotension.

We report 2 patients who had clinical and neuroimaging signs of spontaneous intracranial hypotension and who developed cerebral sinus venous thrombosis. This sequence of events -- known after dural puncture but not in spontaneous intracranial hypotension -- was suggested by the change in the pattern of headache, from a postural to a permanent and increasing one. The diagnostic and therapeutic difficulties that this complication raises are discussed.