Comparison of photon-counting CT and conventional CT for cochlear implant preoperative planning.

Introduction: Accurate cochlear measurements are crucial for personalized cochlear implantation, requiring high-quality imaging for precise cochlear duct length (CDL) assessment. Photon-counting computed tomography (PC-CT) is an advanced imaging technique that enhances image quality while reducing radiation exposure. The aim of this study was to compare PC-CT and conventional CT in cochlear measurements using cochlear implant planning software in patients with a unilateral cochlear implant.

Method: This prospective study was conducted at a tertiary referral center. All patients had a previous conventional temporal bone CT before cochlear implantation and a PC-CT of the temporal bone for the post implant evaluation. Image analysis for both PC-CT and CT was performed with the OTOPLAN version 3.0 software manually and independently by three different otologist experts in the field.

Results: Ten cochleae were evaluated. The mean full CDL was 35.81 ± 1.22 mm in CT and 35.99 ± 1.94 mm in PC-CT (P = 0.77) Inter-observer reliability was poor for CT with an intra-correlation coefficient of 0.16 and moderate for PC-CT with an intra-correlation coefficient of 0.71.

Conclusion: This study demonstrated the advantages of PC-CT over conventional CT by improving the reliability and reproducibility of CDL measurements in patients.