Transmastoid repair of superior semicircular canal dehiscence

Abstract

Objective/Hypothesis Superior semicircular canal (Sup SC) dehiscence syndrome is a rare condition, causing a variety of auditory and vestibular symptoms. The traditional surgical management is a middle cranial fossa, extradural approach to resurface the Sup SC. Recently, a transmastoid approach for plugging of the Sup SC has been developed. We present further data supporting the use of the transmastoid approach in preference to the middle fossa approach. Design This is a retrospective multi-institutional case series. Method We included 10 patients in this case series from two tertiary otology institutions. Sup SC dehiscence was confirmed by correlation of clinical symptoms with positive audiometric, vestibular evoked myogenic potential, and computed tomography findings. A transmastoid approach was used for plugging of the Sup SC. Either a single fenestration was created at the site of dehiscence or separate fenestrations sited ampullopetal and ampullofugal to the dehiscence. Results All patients who underwent this procedure had good symptom control and hearing preservation postoperatively. Conclusion In patients with adequate temporal bone pneumatization, the transmastoid approach provides a safe and effective alternative to the middle cranial fossa approach. This series has demonstrated excellent symptom control and preservation of hearing with the transmastoid approach.

Keywords: plugging; superior semicircular canal dehiscence; transmastoid.

Figure 1

Intraoperative photo 1 demonstrating the blue lined the superior semicircular canal.

Figure 2

Intraoperative photo of the superior semicircular canal opened with 90-degree hook.

Figure 3

Intraoperative photo of fascia plugging the superior semicircular canal.

Figure 4

Intraoperative photo 3 demonstrating appearance of the superior semicircular canal after plugging.