双源CT鉴别诊断炎症性肠病反应性增生淋巴结与结直肠癌转移性淋巴结

Dual-source CT in Differential Diagnosis of Inflammatory Bowel Disease Reactive Hyperplasia Lymph Nodes and Metastatic Lymph Nodes of Colorectal Cancer

目的探讨双源CT双能量扫描中碘含量及能谱曲线对炎症性肠病反应性增生淋巴结与结直肠癌转移性淋巴结诊断的临床价值。资料与方法收集有完整双能量扫描资料并经肠镜或手术病理证实的30例炎症性肠病(15例溃疡性结肠炎、15例克罗恩病)共51枚反应性增生淋巴结及20例结直肠癌共35枚转移淋巴结进行回顾性分析。测量反应性增生淋巴结及转移性淋巴结的碘含量;并比较2种不同病理性质淋巴结的能谱曲线斜率,采用受试者工作特性曲线,选取鉴别诊断2种不同病理性质淋巴结的最佳敏感度和特异度。结果动脉期炎症性肠病反应性增生淋巴结与结直肠癌转移性淋巴结碘含量分别为(2.66±0.70)mg/ml、(1.65±0.81)mg/ml,曲线斜率分别为2.81±0.56、0.14±0.09,反应性增生淋巴结与转移性淋巴结两者的动脉期碘含量及能谱曲线斜率差异均有统计学意义(P<0.05)。且能谱曲线斜率对炎症性肠病反应性增生淋巴结与结直肠癌转移性淋巴结的诊断效能高于碘含量,其敏感度为96.7%,特异度为76.7%,曲线下面积为0.846。结论双源CT双能量动脉期测量碘含量及能谱曲线斜率对炎症性肠病反应性增生淋巴结与结直肠癌转移性淋巴结的鉴别诊断具有一定的意义,且能谱曲线斜率优于碘含量。

Purpose To explore the clinical value of iodine content and energy spectrum in dual-source dual-energy CT scan in the diagnosis of inflammatory bowel disease reactive hyperplasia lymph nodes（LNs） and metastatic LNs in patients with colorectal cancer. Materials and Methods Complete dual energy scanning data of 51 reactive LNs in 30 patients with inflammatory bowel disease（15 cases of ulcerative colitis, 15 cases of Crohn＇s disease） and 35 metastatic LNs in 20 patients with colorectal cancer confirmed by colonoscopy or pathology were collected and retrospectively analyzed. The iodine contents of reactive hyperplasia LNs and metastatic LNs were detected and the slopes of energy spectrum curves were compared between the two different pathological LNs. Moreover, the receiver operating characteristic curve was applied to determine the optimum sensitivity and specificity of differential diagnosis of these two kinds of LNs. Results The iodine contents of inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs in patients with colorectal cancer in arterial phase were（2.66±0.70） mg/ml and（1.65±0.81） mg/ml, and the slopes of curves were 2.81±0.56 and 0.14±0.09, respectively. There were significant differences in the iodine contents and the slopes of the energy spectral curves between these two kinds of LNs in arterial phase（P〈0.05）. Moreover, the diagnostic efficacy of energy spectrum curve slope, of which the sensitivity, specificity and area under the curve was 96.7%, 76.7% and 0.846, respectively; was higher than those of iodine content in diagnosing inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs. Conclusion Dual-source dual-energy CT-derived arterial phase measurement of iodine content and slope of energy spectral curve has certain significance for differential diagnosis of inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs, and the slope of spectral curve is superior to iodine.