RT Journal Article
SR Electronic
T1 Pre- and Postoperative Imaging of Cochlear Implantation in Cadaveric Specimens Using Low-Dose Photon-Counting Detector CT
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 362
OP 371
DO 10.3174/ajnr.A8533
VO 46
IS 2
A1 Spahn, Bjoern
A1 Müller-Graff, Franz-Tassilo
A1 Rak, Kristen
A1 Engert, Jonas
A1 Voelker, Johannes
A1 Hackenberg, Stephan
A1 Hagen, Rudolf
A1 Neun, Tilmann
A1 Petritsch, Bernhard
A1 Bley, Thorsten Alexander
A1 Grunz, Jan-Peter
A1 Huflage, Henner
YR 2025
UL http://www.ajnr.org/content/46/2/362.abstract
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