Effectiveness of Photon-Counting CT for Metal Artefact Reduction in Musculoskeletal Imaging: A Structured Literature Review

Abstract

Abstract Aim: This structured literature review systematically evaluated the effectiveness of photon-counting detector computed tomography (PCD-CT) for reducing metal artefacts in musculoskeletal imaging involving orthopaedic implants. Background: Metal artefacts from orthopaedic implants substantially degrade diagnostic image quality in conventional computed tomography, compromising visualisation of periprosthetic anatomy essential for detecting complications. With arthroplasty procedures increasing substantially and photon-counting CT recently introduced into clinical practice (2021), systematic evidence synthesis was required to establish effectiveness, identify optimal imaging parameters, and determine clinical implementation readiness. Methods: A structured literature review was conducted following PRISMA guidelines. PubMed was searched for studies published between 2019 and 2024 evaluating PCD CT for metal artefact reduction in musculoskeletal imaging. Included studies were appraised using the QUALSYST quality assessment tool. Data were extracted systematically and synthesised narratively, examining quantitative artefact metrics, subjective image quality assessments, and optimal reconstruction parameters. Results: Five studies (134 patients plus phantom investigations) met inclusion criteria, achieving good to excellent methodological quality ratings (73.1%-100%). PCD-CT demonstrated substantial artefact reductions ranging from 59% to 83%, substantially exceeding the 30-50% reductions typically achieved with conventional approaches. Virtual monoenergetic imaging at 100-140 keV combined with iterative metal artefact reduction algorithms emerged as optimal reconstruction strategies. Radiologists consistently rated PCD-CT reconstructions as superior to comparator conditions, with enhanced visualisation of periprosthetic bone, soft tissues, and adjacent anatomical structures. Evidence limitations included modest sample sizes, single-vendor concentration, predominance of retrospective designs, and absence of patient-important outcome measures. Conclusion: PCD-CT represents a significant technological advancement, providing substantial and reproducible improvements in metal artefact reduction and image quality in musculoskeletal imaging. Current evidence supports cautious clinical implementation in centres with access to photon-counting CT systems, whilst highlighting essential research priorities including larger prospective studies, multi-vendor evaluations, broader implant representation, and patient-centred outcome research.