Revista de Otologia e Rinologia

Cochlear-Internal Carotid Artery Dehiscence with a Pathologic Electrocochleography

P. Mittmann, A. Ernst and I. Todt

Cochlear-Internal Carotid Artery Dehiscence with a Pathologic Electrocochleography

Dehiscences of labyrinthine structures are mainly defects of the semicircular canals. Cochlear-carotid dehiscences are rare and were first described in 2004. We present the case of a 58-yearold woman presented at our clinic with intermittent vertigo and nonpulsatile tinnitus on the right side for over 6 months. Vertigo could not be associated with any specific activity or movement and was not provokable. High resolution computed tomography showed a bony dehiscence of the apical cochlea on the right side in contact with the internal carotid artery. Magnetic resonance imaging showed contact between the cochlea and the internal carotid artery. Under oral medication with Betahistin 12 mg three times a day in combination with antihypertensive medication, symptoms were regressive. Three months after starting therapy the patient's symptoms were almost absent. A dehiscence of the bony cochlea is a rare malformation that should be kept in mind before stapes surgery. The clinical pattern is variable and shows similarities to SCDS. Treatment options are limited.