Radionuclide cisternography in detecting cerebrospinal fluid leak in spontaneous intracranial hypotension: a series of four case reports.

Spontaneous intracranial hypotension (SIH) is an infrequent clinical entity characterized by cerebrospinal fluid (CSF) hypovolemia due to a CSF leak. The cause of the leak in SIH, however, is largely unknown, though structural meningeal weakness and mechanical stress factors have been postulated. Patients with SIH typically present with postural headaches, and occasionally with other symptomology as well, such as nausea, emesis, neck stiffness, and photophobia. In this case series, we present 4 patients who underwent radionuclide cisternography (RNC) for suspected CSF leak. All patients underwent RNC and MR and/or CT for evaluation. We found that RNC accurately detected and localized a CSF abnormality in all 4 patients, with each patient experiencing symptomatic relief following directed epidural blood patch.