Our Experience with Superior Semicircular Canal Dehiscence

Objective: We would like to share our experience with the investigative work up and management of superior semicircular canal dehiscence in our lateral skull base unit in past 7 years.

Method: Retrospective case note analysis of 6 patients. Our patients presented with the classical symptoms of Tullio phenomenon, namely, dizziness on exposure to loud sound. 4 patients underwent middle fossa approach repair of dehiscence. VEMP was negative in one patient but had complete resolution of symptoms after repair. Our diagnosis was based more on clinical indicators and investigative parameters on radiology. We do not drill the arcuate eminence as proposed by some skull base units. The middle cranial fossa approach with the help of stealth image guided system was used in one patient to minimize dural elevation. Autologous material was used in all cases. All our patients have improved significantly postoperatively with no morbidity. Two patients opted conservative approach as symptoms resolved after few months.

Conclusion: We found that clinical indicators were more reliable than investigative parameters such as VEMP. Although all our patients were VEMP negative, they improved dramatically after the surgery. The middle cranial fossa approach helped management of these patients with preservation of hearing in all patients.