Bowel ischemia detection on portal venous CT: multireader evaluation of dual-energy and photon-counting spectral imaging
摘要
To compare the diagnostic performance of portal-venous (PV) blended CT images alone vs PV blended images supplemented with spectral reconstructions for detecting acute bowel ischemia, stratified by scanner platform (dual-energy CT [DECT] vs photon-counting CT [PCCT]).
Materials and methodsThis retrospective single-center, multireader, crossover diagnostic accuracy study compared PV blended images alone (image set A) with PV blended images supplemented by spectral reconstructions (image set B: 40-keV virtual monoenergetic images, iodine maps, and virtual non-contrast images) acquired on DECT and PCCT. The reference standard was a prespecified composite derived from surgical and index-hospitalization documentation. Diagnostic performance was analyzed using mixed-effects logistic models for accuracy, sensitivity, and specificity, cumulative link mixed models for 7-point suspicion scores, and ROC analyses using a multireader multicase framework.
ResultsA total of 378 patients (mean age, 68.1 years ± 7.4, 206 men) were evaluated. 150/378 (39.7%) were ischemia-positive by the composite reference standard. Accuracy increased from 73% (95% CI: 68–77) with blended images to 86% (82–89) with spectral reconstructions (OR: 2.30; 95% CI: 1.70–3.10; p < 0.001). Sensitivity increased from 75% (68–82) to 87% (81–92) (p = 0.008) and specificity from 72% (65–78) to 86% (80–90) (p < 0.001). Mean AUC improved by 0.16 (95% CI: 0.12–0.20; p < 0.001). Effects were similar on DECT and PCCT (interaction p = 0.24).
ConclusionAdding spectral reconstructions to PV blended images improved accuracy, sensitivity, specificity, and diagnostic confidence for bowel ischemia detection, without evidence of platform-specific effect modification.
Key Points