Tinnitus caused by bilateral shunts from the occipital arteries to the intracranial veins. A case report.

A patient with objective tinnitus and a pulse synchronous murmur over both left and right sides of the mastoid regions is described. Microphones placed over the mastoid regions recording "phonomastoidograms" clearly demonstrated the pulse synchronous tinnitus. Arteriovenous shunts from the occipital arteries to the sigmoid sinus were later demonstrated with angiograms. After bilateral surgical removal of the arteriovenous shunts the incapacitating tinnitus disappeared. The importance of thorough examination of pulse synchronous tinnitus is discussed.