Abstract: Objective To investigate the clinical, cerebrospinal fluid(CSF) and imaging characteristics of intracranial hypotension syndrome (IHS) and its prognosis.Methods The clinical information of 21 cases with IHS was retrospectively analyzed.Results All the 21 patients suffered orthostatic headache with different associated symptoms, low CSF pressure (<70 mmH₂O). White blood cells count(WBC) in CSF increased in 6 patients, red blood cells count(RBC) increased in 4 patients, and protein in CSF is high in 10 patients. By cerebral CT, 15 out of 18 cases were normal, subdural hematoma in 2 cases, and subdural dropsy in 1 case. By cerebral MRI, 5 cases were normal, diffuse pachymeningeal thickening and enhancement in 11 cases, and amygdala cerebelli hernia in 2 cases. Large fluid infusion and supportive treatment resulted in good prognosis for them.Conclusion IHS typically presents with position headache, and CSF changes and MRI are of certain characteristic, usually following a good prognosis.

Key words: intracranial hypotension syndrome, cerebrospinal fluid, imaging