Transmastoid Partial Labyrinthectomy for Brainstem Vascular Lesions: Clinical Outcomes and Assessment of Postoperative Cochleovestibular Function

Abstract

To discuss the transmastoid partial labyrinthectomy approach for brainstem vascular lesions, with respect to hearing and balance preservation. Retrospective case series. Tertiary referral center (University Health Network, Toronto). Nine consecutive surgical patients between 1999 and 2004. Clinical, audiometric, and electrophysiological vestibular data. Nine transmastoid partial labyrinthectomy procedures (all females) were performed. In seven patients the underlying pathology was an intra-axial brainstem cavernous malformation. Two patients were treated for a basilar artery aneurysm. All patients had progressive neurological signs. Serviceable hearing (pure tone average (PTA): < 50 dB; speech discrimination score (SDS): > 50%) was preserved in seven patients. Partial vestibular function (clinical and electrophysiological) was maintained in most patients. The partial labyrinthectomy approach to the skull base provides excellent exposure while preserving cochleovestibular function in most patients.