Superior semicircular canal dehiscence: Diagnosis and management

Abstract

The authors provide an update on the clinical manifestations, diagnosis and various approaches to the treatment of superior semicircular canal dehiscence (SSCD). SSCD is a rare condition where the bone overlying the superior semicircular canal thins or dehisces causing characteristic clinical findings. Since this was first reported in 1998 by Minor and colleagues, there has been much advancement made in terms of diagnosis and treatment. Signs and symptoms include a wide variation of both vestibular and auditory manifestations. Diagnosis made solely on clinical signs is difficult due to how varied the presentations can be and the overlap with other otologic pathologies. High-resolution CT temporal scans have been the standard in confirming superior semicircular canal dehiscence, however, MRI FIESTA scans have recently been used to image SSCD. Additionally, audiometry and vestibular evoked myogenic potential (VEMP) testing are useful screening tools. Currently, the middle fossa approach is the most common and standard surgical approach to repair SSCD. The transmastoid, endoscopic and transcanal or endaural approaches have also been recently utilized. Presently, there is no consensus as to the best approach, material or technique for repair of SSCD. As we learn more, newer and less invasive approaches and techniques are being used to treat SSCD. We present a comprehensive review of SSCD, including clinical symptoms and presentation, histopathology, diagnosis, treatment strategies and outcomes of intervention.

Keywords: Neurosurgery; Otolaryngology; SSCD; Superior semicircular canal dehiscence; Surgical techniques.