Orthostatic tinnitus: an otological presentation of spontaneous intracranial hypotension

Spontaneous intracranial hypotension (SIH) is a syndrome characterized by orthostatic headache, low cerebrospinal fluid (CSF) pressure without apparent causes for CSF loss, and diffuse pachymeningeal gadolinium enhancement on cranial MRI. Hearing is affected in some patients with SIH. A case of SIH with orthostatic tinnitus is reported. A 51-year-old woman developed a severe headache that was almost completely relieved on recumbency. Cranial MRI with gadolinium infusion showed diffuse enhancement of the dura mater. Radionuclide cisternography demonstrated CSF leaks at the upper and lower thoracic levels. Epidural blood patches at these leak sites alleviated the orthostatic headache, however, orthostatic tinnitus and muffled hearing persisted. Initial audiometry was unremarkable; repeat audiometry performed 6 weeks later demonstrated low-frequency hearing loss in the right ear. Continuous epidural saline infusion for 3 consecutive days was performed; auditory symptoms disappeared 4 weeks thereafter. This case illustrates that orthostatic tinnitus represent intracranial hypotension even in the absence of orthostatic headache. MRI with gadolinium infusion should be carried out in the evaluation of patients with orthostatic tinnitus.