Round Window Visibility Prediction From Preoperative Scanner in Cochlear Implantation: Literature Review and Radiologic Criteria Evaluation

Whereas several surgical techniques exist to perform a cochlear implantation, the most used is the realization of mastoidectomy followed by posterior tympanotomy, in order to expose the round window, which finally permits to access to the cochlea. This procedure might be complicated with facial paresis, loss of residual hearing, because of anatomy relationships in this millimetric area.

CT scan of temporal bone is part of systematic preoperative assessment. Technological advances in radiology during the last decades now provide inframillimetric resolution. Thus, otologic surgeons wish they could anticipate round window exposure from these CT scan. This could decrease the procedure duration, complication occurrence, or improve surgical strategy.

Several studies proposed radiological criteria in this aim, from more or less complex measures in preoperative temporal bone CT scan. However, these diagnostic tests performances have not been assessed for most of them, or compared between them.