Ultra-low-dose CT in extremity fracture detection: A systematic review and meta-analysis

To compare the diagnostic accuracy and radiation doses of ultra-low-dose CT (ULD-CT) versus standard-dose CT (SD-CT) in patients with suspected limb joint fractures.

A systematic review and meta-analysis were conducted following 2020 PRISMA guidelines. Five databases (PubMed, Cochrane, Embase, Scopus, Web of Science) were screened for studies directly comparing ULD-CT to SD-CT diagnostic accuracy for limb joint fractures. Studies used 320-row detector CT scanners with ULD-CT protocols (80 kVp, 4-52 mAs) versus conventional protocols (120 kVp, 50-150 mAs). Bivariate random effects meta-analysis was used to pool sensitivity and specificity estimates. Dose-length product (DLP) reductions were compared directly.

Four prospective studies comprising 674 patients met inclusion criteria. ULD-CT demonstrated pooled sensitivity of 97.6% and specificity of 99.6% (AUC 99.0%), while SD-CT showed sensitivity of 99.4% and specificity of 99.1% (AUC 98.9%). Subgroup analysis revealed no significant differences in sensitivity (p = 0.300) or specificity (p = 0.486). ULD-CT achieved radiation dose reductions of 87-99% across all anatomical regions.

ULD-CT offers significant radiation dose reduction with diagnostic accuracy comparable to SD-CT for limb joint fracture detection. Further multicenter studies are warranted to consolidate evidence across anatomical regions.