双能CT评估TIPS通畅性：定量碘测量及其对诊断性能的影响
本研究回顾性纳入57例TIPS患者，比较标准门静脉期双能CT图像与附加材料分解图像（碘图及虚拟平扫）评估TIPS通畅性的诊断性能与阅读时间，并评估双能CT碘定量的诊断价值。结果表明附加碘图及虚拟平扫可提高特异度并缩短阅读时间，碘浓度测量对TIPS通畅性具有高诊断准确性。
要点
- 附加碘图及虚拟平扫可显著提高TIPS通畅性评估的特异度，敏感度无显著差异。
- 阅读时间从108秒降至97秒，提示材料分解图像可提升阅片效率。
- TIPS/门静脉碘比值及TIPS/下腔静脉碘比值对TIPS通畅性诊断AUC接近1.000。
核心结论
- 附加碘图及虚拟平扫的双能CT可改善TIPS通畅性的视觉评估诊断性能。
- 碘浓度测量为TIPS通畅性提供准确、客观的评估。
研究设计与样本
- 由5名阅片者先后评估标准门静脉期双能CT图像及附加材料分解图像（碘图及虚拟平扫）对TIPS通畅性的诊断。
- 采用McNemar检验比较敏感度与特异度，Wilcoxon符号秩检验比较阅读时间；在下腔静脉、门静脉及TIPS各放置3个感兴趣区测量碘浓度，采用ROC分析及约登指数确定最佳阈值。
诊断标准与关键数值
- 材料分解方案特异度为98%（95%CI：95-100%），显著高于常规方案的93%（95%CI：88-96%），p<0.001。
- 材料分解方案敏感度为91%（95%CI：82-97%），常规方案为97%（95%CI：90-100%），差异无统计学意义（p=0.219）。
- 碘浓度测量诊断TIPS通畅性的AUC：绝对碘浓度为0.998，TIPS/门静脉比值为1.000，TIPS/下腔静脉比值为0.995。
- 最佳阈值分别为1.40 mg/mL、0.262、0.263，对应敏感度/特异度分别为95%/100%、100%/100%、98%/100%。
临床应用与阅片要点
- 在门静脉期双能CT中附加碘图及虚拟平扫可减少TIPS通畅性评估的假阳性，提高报告可信度。
- 利用TIPS/门静脉或TIPS/下腔静脉碘比值进行定量评估，可获得接近完美的诊断准确性。
局限性
- 回顾性单中心设计，样本量有限（57例），结论需多中心前瞻性研究验证。
- 研究未报告阅片者间一致性及碘测量重复性数据。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
OBJECTIVE: To compare diagnostic performance and reading time between standard portal-venous Dual-energy CT (DECT) images and additional material decomposition images (iodine maps and virtual non-contrast (VNC) images) for assessing transjugular intrahepatic portosystemic shunt (TIPS) patency, and to evaluate the diagnostic value of DECT-derived iodine measurements.
METHODS: This retrospective single-center study included 57 consecutive patients with TIPS who underwent portal-venous DECT between November 2014 and July 2024. Five readers assessed standard portal-venous DECT images, and in a second session, additional material decomposition images for TIPS patency. Sensitivity and specificity between imaging sets were compared using McNemar's test across all reader-patient observations, reading time using the Wilcoxon signed-rank test. Iodine concentrations were measured in the inferior vena cava (IVC), portal vein, and TIPS using three regions of interest each. Receiver operating characteristic (ROC) analysis and Youden index determined optimal thresholds and diagnostic performance for absolute iodine concentration and iodine ratios (TIPS/portal vein, TIPS/IVC).
RESULTS: Specificity was significantly higher with the material decomposition protocol than with the conventional protocol (98%, 95% CI: 95-100% vs. 93%, 95% CI: 88-96%; p < 0.001), while sensitivity did not differ significantly between protocols (91%, 95% CI: 82-97% vs. 97%, 95% CI: 90-100%; p = 0.219). Reading time decreased from 108 to 97 s (p < 0.001). Iodine concentration measurements achieved AUCs of 0.998 for absolute iodine concentration, 1.000 for the TIPS/portal vein ratio, and 0.995 for the TIPS/IVC ratio. Optimal thresholds (1.40 mg/mL, 0.262, 0.263) yielded sensitivities/specificities of 95%/100%, 100%/100%, and 98%/100%, respectively.
CONCLUSION: Additional iodine maps and VNC images in DECT yield improved diagnostic performance in the visual assessment of TIPS patency. Iodine concentration measurements offer accurate, objective assessment of TIPS patency.
引用
- Oberparleiter M, Vosshenrich J, Breit HC, et al. Dual-energy CT for TIPS patency assessment: quantitative iodine measurements and impact on diagnostic performance. Eur J Radiol. 2026. PMID: 42217287. doi:10.1016/j.ejrad.2026.112945
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。