Horsthuis Karin, Lavini Cristina, Bipat Shandra, Stokkers Pieter C F, Stoker Jaap
Departments of Radiology and Gastroenterology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
Radiology. 2009 May;251(2):380-7. doi: 10.1148/radiol.2512072128.
To prospectively determine clinical value of dynamic contrast material-enhanced magnetic resonance (MR) imaging in the evaluation of disease activity in perianal Crohn disease (CD).
Patients provided written informed consent. Study approval was waived by an institutional review board. Thirty-three patients with perianal CD underwent pelvic MR imaging; 17 were male (mean age, 37.4 years +/- 10.8 [standard deviation]; age range, 18-54 years) and 16 were female (mean age, 32.0 years +/- 8.3; age range, 16-43 years). Dynamic contrast-enhanced MR imaging was performed; time-intensity curves (TICs) were obtained. Each pixel was classified as one of six predefined TIC shape types. For each MR imaging examination, a region of interest (ROI) was drawn around the fistula on the single section corresponding to the most extensive and most hyperintense lesion; maximum enhancement (ME), slope of enhancement, and TIC shapes were calculated. Absolute and relative numbers of pixels for each curve type were calculated in a two-dimensional ROI. These results were compared with Perianal Disease Activity Index (PDAI), C-reactive protein (CRP) level, an MR imaging-based severity score, and clinical outcome. A Spearman rank correlation test was used to calculate correlation coefficients between dynamic contrast-enhanced MR imaging parameters and reference parameters. A Mann-Whitney U test was used to calculate differences in dynamic contrast-enhanced MR imaging parameters between predefined groups of patients.
Significant correlations were found between the absolute amounts of the TIC shape types and PDAI and between ROI volume and PDAI. The ratio of quickly enhancing versus slowly enhancing pixels correlated with higher MR imaging scores as did the ROI volume. The absolute amounts of pixels displaying TIC types 2, 3, 4, and 5 correlated significantly with MR imaging score. CRP level showed a significant correlation with mean ME. Larger numbers of quickly enhancing pixels were observed in patients who needed medication changes or developed new abscesses during follow-up.
Dynamic contrast-enhanced MR imaging can help determine disease activity in perianal CD and might be helpful in selecting a subpopulation of patients who should be monitored more closely for development of more extensive disease.
前瞻性地确定动态对比剂增强磁共振（MR）成像在评估肛周克罗恩病（CD）疾病活动度方面的临床价值。
患者提供书面知情同意书。机构审查委员会豁免了研究批准。33例肛周CD患者接受盆腔MR成像；17例为男性（平均年龄37.4岁±10.8[标准差]；年龄范围18 - 54岁），16例为女性（平均年龄32.0岁±8.3；年龄范围16 - 43岁）。进行动态对比增强MR成像；获取时间 - 强度曲线（TIC）。每个像素被分类为六种预定义的TIC形状类型之一。对于每次MR成像检查，在与最广泛且最强化病变相对应的单一层面上围绕瘘管绘制感兴趣区（ROI）；计算最大强化（ME）、强化斜率和TIC形状。在二维ROI中计算每种曲线类型的像素绝对数量和相对数量。将这些结果与肛周疾病活动指数（PDAI）、C反应蛋白（CRP）水平、基于MR成像的严重程度评分以及临床结果进行比较。采用Spearman等级相关检验计算动态对比增强MR成像参数与参考参数之间的相关系数。采用Mann - Whitney U检验计算预定义患者组之间动态对比增强MR成像参数的差异。
发现TIC形状类型的绝对数量与PDAI之间以及ROI体积与PDAI之间存在显著相关性。快速增强像素与缓慢增强像素的比例与更高的MR成像评分相关，ROI体积也是如此。显示TIC类型2、3、4和5的像素绝对数量与MR成像评分显著相关。CRP水平与平均ME显著相关。在随访期间需要改变药物治疗或出现新脓肿的患者中观察到更多快速增强像素。
动态对比增强MR成像有助于确定肛周CD的疾病活动度，可能有助于选择应更密切监测以发现更广泛疾病发展的亚组患者。
