A rare, mostly benign, primary tumor of the meninges (arachnoid cap cells), usually located in the supratentorial compartment, commonly appearing in the sixth and seventh decade of life, clinically silent in most cases or causing hyperostosis close to the tumor and resulting in focal bulging and localized pain in less than 10% of cases. Additional features may include headache, seizures, gradual personality changes (apathy and dementia), anosmia, impaired vision, exophthalmos, hearing loss, ataxia, dysmetria, hypotonia, nystagmus, and rarely spontaneous bleeding.

Pulsatile tinnitus is generally classified a kind of objective tinnitus, meaning that it is not only audible to the patient but also to the examiner on auscultation of the auditory canal and/or of surrounding structures with use of an auscultation tube or stethoscope. Usually, pulsatile tinnitus is heard as a lower pitched thumping or booming, a rougher blowing sound which is coincidental with respiration, or as a clicking, higher pitched rhythmic sensation. Pulsatile tinnitus may be associated with vascular abnormalities such as arterioevenous shunts or glomus tumors or the jugular vein, arterial bruits related to a high-riding carotid artery (close to the auditory areas) or carotid stenosis, or venous abnormalities such as a dehiscent jugular bulb or to hypertension. Finally, in some patients, mechanical abnormalities such a spatulous eustachian tubes, palatomyoclonus (small spasms of muscles in the soft palate area), or idiopathic stapedial muscle spasm may represent the underlying cause of pulsatile tinnitus.