PT  - JOURNAL ARTICLE
AU  - Spahn, Bjoern
AU  - Müller-Graff, Franz-Tassilo
AU  - Rak, Kristen
AU  - Engert, Jonas
AU  - Voelker, Johannes
AU  - Hackenberg, Stephan
AU  - Hagen, Rudolf
AU  - Neun, Tilmann
AU  - Petritsch, Bernhard
AU  - Bley, Thorsten Alexander
AU  - Grunz, Jan-Peter
AU  - Huflage, Henner
TI  - Pre- and Postoperative Imaging of Cochlear Implantation in Cadaveric Specimens Using Low-Dose Photon-Counting Detector CT
AID  - 10.3174/ajnr.A8533
DP  - 2025 Feb 01
TA  - American Journal of Neuroradiology
PG  - 362--371
VI  - 46
IP  - 2
4099  - http://www.ajnr.org/content/46/2/362.short
4100  - http://www.ajnr.org/content/46/2/362.full
SO  - Am. J. Neuroradiol.2025 Feb 01; 46
AB  - BACKGROUND AND PURPOSE: Anatomically adapted cochlear implantation and efficient postoperative cochlear implant-fitting strategies benefit from reliable and highly detailed imaging techniques. Since image quality in CT is related to the applied radiation dose, this study aimed to evaluate low-dose cochlear imaging with a photon-counting detector by investigating the accuracy of pre- and postoperative cochlear analysis.MATERIALS AND METHODS: Photon-counting CT images of 10 temporal bone specimens were acquired with 3 different radiation dose levels (regular dose: 27.1 mGy, low dose: 4.81 mGy, and ultra-low dose: 3.43 mGy) before and after cochlear implant electrode carrier insertion. A clinical scan protocol was used with a tube potential of 120 kV in ultra-high-resolution scan mode (detector collimation 120 × 0.2 mm). The accuracy of cochlear duct length measurements for the organ of Corti and electrode contact determination was investigated for all applied settings by 2 independent otosurgeons.RESULTS: No substantial differences were ascertained between photon-counting CT scans performed with standard dose and dedicated low-dose imaging regarding the accuracy of neither pre- and postoperative cochlear analysis nor postoperative cochlear implant electrode analysis. Radiation dose reduction of 82.3% (low dose) and 87.3% (ultra-low dose) could be realized compared with the clinical standard protocol.CONCLUSIONS: Ultra-high-resolution cochlear imaging is feasible with very low radiation exposure when using a first-generation photon-counting CT in combination with dedicated low-dose protocols. The accuracy of pre- and postoperative cochlear analysis with the applied dose reduction settings was comparable with a clinical regular-dose protocol.AIDangular insertion depthCDLcochlear duct lengthCDLLWcochlear duct length of the lateral cochlea wallCDLOCcochlear duct length of the organ of CortiCTDIvolvolume CT dose indexDLPdose-length productEIDenergy-integrating detectorICCintraclass correlation coefficientILinsertion lengthLDlow dosePCDphoton-counting detectorRDregular doseSDstandard deviationULDultra-low dose