Precision imaging biomarkers for gout: artifact-specific spectral CT parameters for personalized differentiation of tophi in a prospective study
Yiteng Zhang, Yu Zhang, Yi Liu, Hanyu Li, Zejun Liang, Jianrong He, Jun Xie, Zhenlin Li, Jing TangBackground:
Spectral computed tomography (CT) enables non-invasive visualization and quantification of monosodium urate deposits and has an important role in gout diagnosis and monitoring. However, artifact-related false-positive findings may reduce diagnostic confidence, particularly when artifacts show attenuation features overlapping with tophi.
Objectives:
To evaluate advanced spectral CT parameters as quantitative imaging biomarkers for differentiating tophi from common artifacts.
Design:
Prospective cross-sectional study.
Methods:
Consecutive participants with suspected foot gout were prospectively recruited from May 2023 to May 2024 and underwent foot spectral CT scans. Participants were classified into gout and non-gout groups. Regions of interest (ROIs) were delineated on index tophi in the gout group and on artifact regions in the non-gout group, including nail bed, skin, beam-hardening, vascular, and tendon artifacts. Conventional attenuation (HU 120-kV ) and three advanced spectral parameters (effective atomic number (Zeff), electron density (ED), and dual-energy ratio (DER)) were measured and compared. Diagnostic performance of each parameter was assessed using receiver operating characteristic curves and the area under the curve (AUC).
Results:
The final analysis included 82 tophus ROIs and 243 artifact ROIs. Tophi differed significantly from beam-hardening, vascular, and tendon artifacts across all parameters (
Conclusion:
Spectral CT parameters may support artifact-specific tophus differentiation in gout. An artifact-specific parameter selection approach may help reduce false-positive interpretations and improve confidence in spectral CT-based gout assessment.
Trial registration:
Chinese Clinical Trial Registry, ChiCTR2300069114,