PREOPERATIVE TEMPORAL BONE COMPUTED-TOMOGRAPHY SCAN AND ITS USE IN EVALUATING THE PEDIATRIC COCHLEAR IMPLANT CANDIDATE

Preoperative computed tomography (CT) scan evaluation of the temporal bones in cochlear implant candidates plays a crucial role in determini ng candidacy and the side of implantation. The CT scans allow the surg eon to carefully review the anatomy of the inner ear and mastoid cavit y in order to predict any potential difficulties or complications that may be encountered during the implant insertion. We retrospectively r eviewed 50 preoperative CT scans of the temporal bone in children who have been successfully implanted. In these scans, we assessed the degr ee of mastoid pneumatization, cochlear anatomy and patency, size of th e vestibular aqueduct, cochlear aqueduct, and internal auditory canal. We analyzed our findings and measurements and compared our results wi th the degree of difficulty noted in the insertion of the implant, the number of electrodes inserted in each case, and the overall complicat ion rate. From this radiographic review, we have created a checklist f or cochlear implant surgeons in order to highlight key features that n eed to be recognized in the temporal bone scan in preoperative evaluat ion of cochlear implant candidates.