Prediciton of the Round Window Visibility Through Posterior Tympanotomy by CT Scan Analysis

Preoperative CT Scan Analysis to Predict Perioperative Round Window Visibility Through the Posterior Tympanotoy in Cochlear Implant Surgery

It is difficult to predict the intraoperative visibility of the round window through the posterior Tympanostomy. In case of non-visualization, the surgeon may have to change operative technique during cochlear implant surgery.

The primary purpose of the study is to define relevant CT measurements on the preoperative scanner to predict the perioperative visibility of the round window. Define relevant CT measurements on the preoperative scanner to predict the perioperative visibility of the round window.

The secondary purpose is to validate the investigator's scanner reading protocol for a prospective study.

Inclusion Criteria:

• Aged subject from 9 months and over
• Implanted cochlear subject in the ENT department of Strasbourg between 1st January 2010 and 1st March 2018
• Subject (or the holders of parental authority in the case of minors) having agreed to the use of medical data for the purpose of this research.

Exclusion Criteria:

• Refusal of the patient to participate in the study
• CROP does not make it possible to evaluate the visibility of the FR
• Preoperative or uninterpretable scanner
• Major anatomical malformation
• Subject under the protection of justice
• Subject under guardianship or curatorship