Radiology, Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa.
Paediatric Radiology Unit, Meyer Children's Hospital, Florence.
J Pediatr Gastroenterol Nutr. 2019 Mar;68(3):353-359. doi: 10.1097/MPG.0000000000002178.
The aim of the study was to establish an apparent diffusion coefficient (ADC) cut-off value to classify active and non-active lesions in inflammatory bowel disease.
We reviewed 167 paediatric magnetic resonance enterographies executed for suspected inflammatory bowel disease by using a 1.5- and 3-T scanner. We assessed the presence and activity of the disease by using morphologic and functional parameters such as the ADC. Each patient could have more than 1 examinations. Quantitative assessment of disease activity in the ADC map was measured placing 3 regions of interest in the areas of highest inflammation and the mean value was calculated, patients without sign of inflammation were assessed at 2 standardised site. Ileocolonoscopy, esophagogastroduodenoscopy, surgery, and video-capsule endoscopy were used as standards of reference.
We enrolled 34 patients and 35 examinations: radiological findings of disease were identified in 29 examinations and 44 lesions were detected. Six patients had negative results and ADC assessment was taken at the terminal ileum and cecum. A total of 56 bowel segments were included in the study. Image analysis revealed 39 active lesions (69.6%) and their ADC values were lower compared to the ones of non-active segments. For each scanner a cut-off value was found (sensitivity: 0.91, specificity: 0.89 for 1.5 T and 0.81 for 3 T). Inter-rater agreement on disease activity between ADC values and magnetic resonance enterography results and between ADC values and the standard of reference were very good.
ADC can provide a scanner-based quantitative measurement of disease activity.
本研究旨在建立一个表观扩散系数（ADC）截断值，以对炎症性肠病的活动和非活动病变进行分类。
我们回顾了 167 例因疑似炎症性肠病而接受 1.5 和 3-T 磁共振肠成像检查的儿科患者。我们使用形态学和功能参数（如 ADC）评估疾病的存在和活动情况。每位患者可能有多个检查。通过在炎症最严重的区域放置 3 个感兴趣区域，在 ADC 图上对疾病活动进行定量评估，并计算平均值，对没有炎症迹象的患者在 2 个标准化部位进行评估。回肠结肠内镜检查、食管胃十二指肠镜检查、手术和胶囊内镜检查被用作参考标准。
我们共纳入 34 例患者和 35 次检查：29 次检查显示有疾病的放射学表现，共发现 44 个病灶。6 例患者结果为阴性，ADC 评估在回肠末端和盲肠进行。共有 56 个肠段纳入研究。图像分析显示 39 个活动病变（69.6%），其 ADC 值低于非活动病变。对于每种扫描仪，都发现了一个截断值（1.5 T 的灵敏度为 0.91，特异性为 0.89，3 T 的灵敏度为 0.81）。ADC 值与磁共振肠成像结果之间以及 ADC 值与参考标准之间的疾病活动的观察者间一致性非常好。
ADC 可以提供基于扫描仪的疾病活动定量测量。
