Intraoperative use of cone-beam computed tomography in a cadaveric ossified cochlea model

Objectives: To describe a cadaveric temporal bone model of labyrinthitis ossificans and investigate the utility of intraoperative cone-beam computed tomography (CBCT) in the facilitating cochlear implantation. Design: Cadaveric temporal bone study. Methods: Five cadaveric heads had cement introduced into the 10 cochleas. CBCT and a conventional CT scan were compared to assess the extent of cochlear obliteration. The cement was drilled-out (under CBCT guidance, if required) and cochlear implant electrode arrays (from 3 different manufacturers) inserted. Results: CBCT images demonstrated temporal bone anatomy and the extent of cochlear obliteration as clearly as conventional CT in all cases. Intraoperative CBCT guided drilling and facilitated electrode placement in two of five heads (3 of 10 ears). Streak-artifact from the electrodes of two devices partially obscured image clarity. Conclusions: The obliterated cochlear model reproduced a disease-ossified cochlear both radiographically and surgically. CBCT is useful for intraoperative imaging to facilitate electrode array placement in the obliterated or congenitally abnormal cochlea.