Objective: To discuss the different methods of computed tomography (CT) scans and three dimensional reconstruction of inner ear with implanted electrodes, and to evaluate the value and image features of these methods.
Method: Six cochlear implant (MEDEL Combi 40+, Advanced Bionics) recipients were involved in this study. The implanted electrodes of all patients were examined on the seventh postoperative day. The data of the CT scans was transferred to workstation for three dimensional reconstruction by volume rendering (VR), average intensity projection (AIP) and surface shaded display (SSD).
Result: The three methods of three dimensional reconstruction provided satisfactory image of implanted electrode including the shape and the special relationship of the electrode in the inner ear. The insertion depth of the electrode can be evaluated directly. Moreover, each of the electrode pairs can be identified clearly.
Conclusion: Postoperative evaluation of the implanted electrode with three methods of CT scans with three dimensions reconstruction of inner ear provide more accurate image of the special relationship of the electrode in the cochlear canal with direct demonstration of electrode insertion depth in the cochlea.