Abstract: Objective To investigate the clinical characteristics of spontaneous intracranial hypotension (SIH) and explore the underlying mechanism and therapeutic strategies. Methods The clinical and radiographic features of 14 SIH cases were retrospectively analyzed. The published literatures related to SIH were reviewed. Results All patients showed orthostatic headache (14/14), which was complicated with nausea/vomiting in 8 cases (8/14), and with compulsive posture in 7 cases (7/14). Orthostatic cranial nervous impairments included dizziness (11/14), hearing loss and tinnitus (7/14), diplopia (3/14), blurred vision (1/14), facial paresthesia (1/14) and true bulbar paralysis (1/14). Other orthostatic nervous impairments were cerebellar ataxia (4/14), conscious disturbance (2/14), hypermyotonia (2/14), positive pathological reflex (1/14), personality changes (1/14) and urine retention (1/14). Magnetic resonance imaging (MRI) showed diffuse meningeal enhancement (10/14), subdural effusion(10/14), brain sagging (10/14), cerebral hernia (6/14), smaller angle between Galen vain and straight sinus (2/14) and cerebral venous sinus thrombosis (1/14). Conclusion The clinical and radiographic manifestations of SIH are varied, and orthostatic feature is the most important factor leading to the diagnose. As the potential cause of SIH is spontaneous cerebrospinal fluid leak, conservative therapy, blood patch and surgery are effective management.

Key words: Intracranial hypotension, Headache, Body position