Kim Kyung-Jo, Lee Yedaun, Park Seong Ho, Kang Bo-Kyeong, Seo Nieun, Yang Suk-Kyun, Ye Byong Duk, Park Sang Hyoung, Kim So Yeon, Baek Seunghee, Ha Hyun Kwon
*Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea; †Department of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Korea; ‡Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea; and §Department of Clinical Epidemiology and Biostatistics, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
Inflamm Bowel Dis. 2015 Jan;21(1):101-9. doi: 10.1097/MIB.0000000000000222.
Diffusion-weighted imaging (DWI) is a novel technique to evaluate bowel inflammation in Crohn's disease (CD). It is unknown whether and how DWI adds to the accuracy of conventional magnetic resonance enterography (MRE).
Fifty consecutive adults suspected of CD prospectively underwent clinical assessment, conventional MRE and DWI at b = 900 sec/mm without water enema, and ileocolonoscopy within 1 week. MRE images were interpreted with proper blinding. Forty-four patients finally diagnosed with CD (male:female, 34:10; 26.9 ± 6.1 yr) were analyzed. The per-segment accuracy of MRE for diagnosing active CD was assessed in the terminal ileum, right colon, and rectum using location-by-location matching with endoscopy as the reference standard.
The study evaluated 58 bowel segments with deep or superficial ulcers, 34 with aphthae, erythema, or edema only, and 35 without inflammation. Conventional MRE + DWI was more sensitive for bowel inflammation than conventional MRE alone (83% [76/92] versus 62% [57/92]; P = 0.001) largely because of additional detection of aphthae, erythema, or edema. The sensitivities for deep and overt ulcers were similar regardless of DWI, ranging from 88% to 97%. Conventional MRE + DWI was less specific than conventional MRE alone (60% [21/35] versus 94% [33/35]; P < 0.001), mostly because of many false positives in the colorectum. Positive DWI findings in the bowel showing active inflammation on conventional MRE were associated with higher Crohn's disease endoscopic index of severity score (P = 0.021) and deep ulcers (P = 0.01; diagnostic odds ratio, 12).
DWI performed without water enema is not useful for incremental detection of bowel inflammation. DWI may help identify more severe inflammation among bowel segments showing active inflammation on conventional MRE.
扩散加权成像（DWI）是一种评估克罗恩病（CD）肠道炎症的新技术。DWI是否以及如何提高传统磁共振小肠造影（MRE）的准确性尚不清楚。
连续50例疑似患有CD的成年人前瞻性地接受了临床评估、在未进行水灌肠的情况下b = 900 sec/mm的传统MRE和DWI检查，并在1周内接受了回结肠镜检查。MRE图像在适当的盲法下进行解读。对最终确诊为CD的44例患者（男：女，34：10；26.9±6.1岁）进行分析。以内镜检查为参考标准，通过逐部位匹配评估MRE在回肠末端、右结肠和直肠诊断活动性CD的各节段准确性。
该研究评估了58个有深部或浅表溃疡的肠段、34个仅有阿弗他溃疡、红斑或水肿的肠段以及35个无炎症的肠段。传统MRE + DWI对肠道炎症的敏感性高于单独的传统MRE（83% [76/92] 对62% [57/92]；P = 0.001），主要是因为额外检测到了阿弗他溃疡、红斑或水肿。无论是否使用DWI，对深部和明显溃疡的敏感性相似，范围为88%至97%。传统MRE + DWI的特异性低于单独的传统MRE（60% [21/35] 对94% [33/35]；P < 0.001），主要是因为在结直肠中有许多假阳性。在传统MRE上显示有活动性炎症的肠道中，DWI阳性结果与更高的克罗恩病内镜严重程度指数评分（P = 0.021）和深部溃疡（P = 0.01；诊断比值比，12）相关。
不进行水灌肠的DWI对肠道炎症的增量检测无用。DWI可能有助于在传统MRE上显示有活动性炎症的肠段中识别更严重的炎症。
