双能量CT碘定量技术对于肠道克罗恩病病灶检出的初步研究

Application Value of lodine Quantification in Detecting the Lesion of Crohn’s Disease Using Dual-Energy CT

目的 本研究通过双能量CT(DECT)定量测量病变肠段的碘浓度(IQ),探讨该方法检出肠道克罗恩病(CD)病灶的可行性,并与常规CT比较,讨论两者对病灶检出的效能差异。方法 回顾性分析40例经临床、内镜和影像学综合诊断的回结肠型CD患者。所有患者接受常规CT扫描和双能量CT三期增强检查,根据结肠镜结果共纳入102个肠段,分为两组(正常组47个肠段,病变组55个肠段)。比较这两种CT图像的定性和定量结果,基于常规CT指征和双能量CT参数分别建立二元Logstc回归模型,并绘制受试者工作特征曲线(ROC)比较两种CT模型对于病灶检出的效能。结果 病变肠段组较正常肠段组相比,常规CT指征:溃疡、梳齿征和增大淋巴结三种征象出现的概率增加以及肠壁增厚均具有显著的统计学差异(P均<0.001);双能量CT参数:动脉期、静脉期、延迟期相对碘浓度(NIC)显著升高(P均<0.001)。二元Logistic回归分析显示常规CT指征(溃疡、梳齿征)、双能量CT参数(动脉期相对碘浓度、静脉期相对碘浓度)有助于CD病灶检出。双能量CT模型比常规CT模型具有更高的效能,曲线下面积(AUC)有统计学差异(0.956vs0.898,p=0.035)。结论 基于DECT的碘定量参数模型能够应用于CD病灶检出的评估,与常规CT相比在检出CD病灶方面具有更高的效能。

Objective Assessment of intestinal lesion detection of Crohn’s disease(CD)is crucial to guide treatment.In this study,we aimed to investigate the lesion detection of dual-energy computed tomography(DECT)by quantitatively measuring the iodine quantification(IQ)of diseased intestinal segments in this assessment and to make a comparison with conventional CT.Methods A total of 102 segments with 40 CD patients underwent DECT scanning.Conventional CT and DECT images were reconstructed.Qualitative and quantitative findings in CT images were compared in this two groups.Binary Logistic regressions were established,based on conventional and DECT parameters,to predict intestinal CD activity.Comparisons were made by receiver operating characteristic(ROC)curve.Results The results showed that ulcers(P<0.001)on CT images,comb sign(P<0.001),Enlarged lymph nodes(P<0.001),bowel wall thickness(P<0.001),arterial phase normalized iodine concentration(NIC),venous phase normalized iodine concentration and delay phase normalized iodine concentration increased significantly with lesion bowel groups(P<0.001).Binary Logistic regressions showed that ulcers,comb sign,arterial phase normalized iodine concentration(NIC)and venous phase normalized iodine concentration contributed to the detection of CD.In predicting intestinal lesion detection,DECT demonstrated higher diagnostic efficiency than conventional CT(AUC=0.956 vs 0.898,P=0.035).Conclusions DECT could be an alternative choice in evaluation of CD.Compared with conventional CT,which had higher diagnostic efficiency in detecting intestinal lesion detection of CD.