Potential of employing a quantum iterative reconstruction algorithm for ultra-high-resolution photon-counting detector CT of the hip

• Published in: Radiography (London, England. 1995) England. 1995), 2023-01, Vol.29 (1), p.44-49
• Main Authors: Huflage, H., Grunz, J.-P., Kunz, A.S., Patzer, T.S., Sauer, S.T., Christner, S.A., Petritsch, B., Ergün, S., Bley, T.A., Luetkens, K.S.
• Format: Article
• Language: English
• Subjects: Algorithms; Bone and Bones; Computed tomography; Humans; Iterative reconstruction; Pelvic imaging; Phantoms, Imaging; Photon-counting; Radiographic Image Interpretation, Computer-Assisted - methods; Tomography, X-Ray Computed - methods
• ISSN: 1078-8174; 1532-2831
• DOI: 10.1016/j.radi.2022.09.010

This study investigated the image quality of a new quantum iterative reconstruction algorithm (QIR) for high resolution photon-counting CT of the hip. Using a first-generation photon-counting CT scanner, five cadaveric specimens were examined with ultra-high-resolution protocols matched for radiation dose. Images were post-processed with a sharp convolution kernel and five different strength levels of iterative reconstruction (QIR 0 – QIR 4). Subjective image quality was rated independently by three radiologists on a five-point scale. Intraclass correlation coefficients (ICC) were computed for assessing interrater agreement. Objective image quality was evaluated by means of contrast-to-noise-ratios (CNR) in bone and muscle tissue. For osseous tissue, subjective image quality was rated best for QIR 2 reformatting (median 5 [interquartile range 5–5]). Contrarily, for soft tissue, QIR 4 received the highest ratings among compared strength levels (3 [3–4]). Both ICCbone (0.805; 95% confidence interval 0.711–0.877; p