Comparison of Image Quality and Radiation Dose in Pediatric Temporal Bone CT using Photon Counting Detectors CT and Energy Integrating Detectors CT

AJNR Am J Neuroradiol. 2024 Apr 8:ajnr.A8276. doi: 10.3174/ajnr.A8276. Online ahead of print.

Abstract

Background and purpose: To compare the image quality and radiation dose of temporal bone CT scans in pediatric patients acquired with photon counting detectors (PCD) CT and energy integrating detectors (EID) CT.

Materials and methods: The retrospective study included a total of 110 pediatric temporal bone CT scans (PCD-CT, n=52; EIDCT, n=58). Two independent readers evaluated the spatial resolution of 4 anatomical structures (tympanic membrane, incudostapedial joint, stapedial crura, and cochlear modiolus) and overall image quality using a 4-point scale. Inter-reader agreement was assessed. Dose length product (DLP) for each CT was compared, and subgroup analyses were performed based on age (under 3 years, 3-5 years, 6-11 years, and 12 years and above).

Results: PCD-CT demonstrated statistically significantly higher scores than EID-CT for all items (tympanic membrane, 2.9 vs. 2.4; incudostapedial joint, 3.6 vs. 2.6, stapedial crura, 3.2 vs. 2.4; cochlear modiolus, 3.4 vs. 2.8; overall image quality, 3.6 vs. 2.8; p<0.05). Inter-reader agreement ranged from good to excellent (ICCs, 0.6-0.81). PCD-CT exhibited a 43% dose reduction compared to EID-CT, with a particularly substantial reduction of over 70% in the subgroups of children under 6 years.

Conclusions: PCD temporal bone CT achieves significantly superior imaging quality at a lower radiation dose compared to EID-CT.

Abbreviations: PCD-CT = photon counting detectors CT; EID-CT = energy integrating detectors CT; DLP = dose length product; AEC = automatic exposure control; ICC = interclass correlation coefficient.