Angular Insertion Depth for Cochlear Implantation: A Comparative Analysis on Precision of CT, MRI, and x-Ray

Area of Science:

• Otolaryngology
• Medical Imaging
• Biomedical Engineering

Background:

• Personalized medicine in cochlear implantation utilizes software for detailed cochlear anatomy analysis.
• This analysis aids in selecting electrode arrays based on individual cochlear duct length (CDL) and supports anatomy-based fitting.
• Various preoperative and postoperative imaging modalities are available, but a direct comparison is lacking.

Purpose of the Study:

• To systematically compare commonly used preoperative and postoperative imaging modalities for cochlear implantation.
• To correlate intracochlear electrode position estimates derived from different imaging techniques.

Main Methods:

• Retrospective study at a tertiary referral center.
• Analysis of 31 cochlear implantations using OTOPLAN software and manual measurements.
• Comparison of preoperative CT, MRI, and postoperative CT with Stenvers view X-ray.

Main Results:

• Postoperative CT and X-ray demonstrated excellent correlation for angular insertion depth.
• Apical contact values from preoperative CT and MRI significantly deviated from postoperative CT.
• Notable variations exist between preoperative and postoperative imaging results.

Conclusions:

• This is the first study to directly correlate intracochlear electrode positions from four imaging modalities.
• High correlation observed between postoperative CT and X-ray measurements.
• Postoperative X-ray analysis is a feasible and efficient method for anatomy-based fitting in cochlear implantation.