Sensorineural complications of stapes surgery are rare but potentially serious. Imaging is usually performed to identify an underlying cause, such as excessive intravestibular penetration of the prosthesis or pneumolabyrinth suggesting perilymphatic fistula.

Unfortunately, there is very little data in an unselected series of uneventful patients.

The aim of this study is to analyze the depth of prosthesis penetration within the vestibule and the rate of pneumolabyrinth the day or the day after the procedure by performing a Cone Beam CT (CBCT) of the temporal bone in a cohort of unselected patients, and to correlate imaging findings to clinical outcome. This prospective monocentric study is conducted in a tertiary referral medical center. A CBCT is performed in 80 consecutive patients having undergone stapes surgery for otosclerosis, the day or the day after the procedure. Penetration length and location of the prosthesis within the vestibule, as well as presence or absence of a pneumolabyrinth are recorded, and compared to clinical data (vertigo, nystagmus, hearing measurement).

Inclusion Criteria:

• age >= 18 years old
• patients undergoing stapes surgery for otosclerosis

Exclusion Criteria:

• patient's refusal to participate in the study
• patient under legal protection
• no medical insurance coverage
• pregnant or breast feeding patient

patients undergoing stapes surgery for otosclerosis