Mulé Sébastien, Brault Baptiste, Blain Maxime, Neifar Nada, Touloupas Caroline, Boulay-Coletta Isabelle, Reizine Edouard, Luciani Alain, Zins Marc
Medical Imaging Department, AP-HP, Henri Mondor University Hospital, 1 rue Gustave Eiffel, 94000, Créteil, France.
Faculty of Health, University of Paris Est Créteil, Créteil, France.
Eur Radiol. 2025 May 6. doi: 10.1007/s00330-025-11635-9.
To investigate the diagnostic value of rapid-kV-switching dual-energy CT (DECT) for identifying bowel ischemia in patients with mechanical small-bowel obstruction (SBO), compared to 120 kVp-equivalent CT.
This retrospective dual-center study included 112 patients with mechanical SBO. Clinical and surgical outcomes with histological findings were recorded as the reference standard. Three readers independently reviewed true unenhanced (TUE) and portal-venous 77-keV virtual monoenergetic images (VMI) (dataset#1), virtual unenhanced (VUE), iodine, and 50-keV VMI (dataset#2). Ischemia was defined as the presence of at least two CT features among reduced bowel-wall enhancement, diffuse mesenteric haziness, and a closed-loop mechanism. Unenhanced bowel-wall attenuation was also analysed. Bowel-wall attenuation and iodine concentration were measured in involved loops and proximal dilated loops. Sensitivity and specificity were calculated for each CT feature. Association between iodine concentration and bowel ischemia was analysed using ROC curves.
Forty-one (37%) patients underwent surgery. Twenty-four (21%) patients had findings of bowel ischemia, including 11 (10%) patients with irreversible ischemia (necrosis). Diagnostic performance for ischemia and necrosis was similar between both datasets for all readers (p > 0.49 for ischemia and p = 1 for necrosis). Increased bowel-wall attenuation on VUE or TUE images had a non-significantly different diagnostic value for all readers (p > 0.21 for ischemia and p > 0.78 for necrosis). Bowel-wall iodine concentration identified bowel necrosis with 82% sensitivity and 83% specificity (optimal cutoff value 1.82 mg/mL).
DECT performed similarly to 120 kVp-equivalent CT for the diagnosis of bowel ischemia in patients with mechanical SBO. VUE images offer a viable alternative to TUE images for the identification of increased bowel-wall attenuation. Bowel-wall iodine concentration accurately identifies bowel necrosis.
Question Dual-energy CT (DECT) could detect small-bowel ischemia caused by mechanical small-bowel obstruction (SBO), but its performance is unknown. Findings Reduced bowel-wall enhancement and increased unenhanced bowel-wall attenuation were not significantly different between DECT and 120 kVp-equivalent CT. Bowel-wall iodine concentration identified necrosis with 82% sensitivity and 83% specificity. Clinical relevance DECT performed similarly to 120 kVp-equivalent CT in depicting bowel ischemia in patients with mechanical SBO, while adding quantitative analysis of bowel-wall iodine concentration may further help identify patients requiring surgery.
与120 kVp等效CT相比，探讨快速千伏切换双能CT（DECT）对机械性小肠梗阻（SBO）患者肠缺血的诊断价值。
这项回顾性双中心研究纳入了112例机械性SBO患者。将临床和手术结果以及组织学检查结果记录为参考标准。三位阅片者独立阅片，包括真平扫（TUE）和门静脉期77 keV虚拟单能图像（VMI）（数据集#1）、虚拟平扫（VUE）、碘图像和50 keV VMI（数据集#2）。肠缺血定义为肠壁强化减弱、肠系膜弥漫性模糊和闭环机制中至少出现两种CT表现。还分析了平扫时肠壁衰减情况。在受累肠袢和近端扩张肠袢中测量肠壁衰减和碘浓度。计算每个CT表现的敏感性和特异性。使用ROC曲线分析碘浓度与肠缺血之间的相关性。
41例（37%）患者接受了手术。24例（21%）患者有肠缺血表现，其中11例（10%）患者存在不可逆缺血（坏死）。所有阅片者在两个数据集中对缺血和坏死的诊断性能相似（缺血p>0.49，坏死p = 1）。VUE或TUE图像上肠壁衰减增加对所有阅片者的诊断价值无显著差异（缺血p>0.21，坏死p>0.78）。肠壁碘浓度对肠坏死的诊断敏感性为82%，特异性为8%（最佳截断值为1.82 mg/mL）。
在诊断机械性SBO患者的肠缺血方面，DECT与120 kVp等效CT表现相似。VUE图像在识别肠壁衰减增加方面可作为TUE图像的可行替代。肠壁碘浓度可准确识别肠坏死。
问题双能CT（DECT）可检测机械性小肠梗阻（SBO）引起的小肠缺血，但其性能尚不清楚。发现DECT与120 kVp等效CT在肠壁强化减弱和未增强肠壁衰减增加方面无显著差异。肠壁碘浓度对坏死的诊断敏感性为82%，特异性为83%。临床意义在描绘机械性SBO患者的肠缺血方面，DECT与120 kVp等效CT表现相似，而增加肠壁碘浓度的定量分析可能有助于进一步识别需要手术的患者。
