Lu Cathy, Gui Xianyong, Chen Wenqian, Fung Tak, Novak Kerri, Wilson Stephanie R
*Division of Gastroenterology, Department of Medicine, University of Calgary, Alberta, Canada; †Department of Pathology and Laboratory Medicine, University of Calgary, Alberta, Canada; ‡Department of Mathematics and Statistics, Information Technologies, University of Calgary, Alberta, Canada; and §Department of Diagnostic Imaging, University of Calgary, Alberta, Canada.
Inflamm Bowel Dis. 2017 Mar;23(3):421-430. doi: 10.1097/MIB.0000000000001020.
Inflammation, fibrosis, and muscular hypertrophy lead to thickened bowel in Crohn's disease forming strictures. Ultrasound shear wave elastography (SWE) measures bowel wall stiffness. Contrast-enhanced ultrasound (CEUS) uniquely detects bowel wall inflammation. We aim to correlate SWE of ileal Crohn's disease in vivo to CEUS peak enhancement and pathology grades of inflammation, fibrosis, and muscular hypertrophy.
In a prospective institutional review board-approved study, 105 consecutive ileal patients with Crohn's disease received ultrasound. At maximal bowel wall thickness (>4 mm), SWE and CEUS were performed. Fifteen patients had ileal resection within a mean time interval of 71.0 ± 66.9 days. Pathology scores for inflammation, fibrosis, and muscular hypertrophy were compared with SWE and CEUS measurements.
Mean in vivo SWE velocity for patients with and without surgery was 2.8 ± 0.7 and 2.2 ± 0.8 m/s (P < 0.01), respectively. In all ileal specimens, chronic exceeded active inflammatory change (P < 0.001). There was an inverse relationship between CEUS peak enhancement and both fibrosis, r = -0.59, P = 0.02, and SWE velocity measurements, r = -0.61, P = 0.03. Strictured bowel specimens had more smooth muscle hypertrophy than fibrosis, P < 0.001. There was moderate correlation between SWE and muscular hypertrophy, r = 0.59, P = 0.02 and no significant relationship between SWE and fibrosis scores (P > 0.05).
Stiffer bowel from smooth muscle hypertrophy increases SWE measurements. We report a novel relation of high SWE with muscle hypertrophy, and inverse relationship with CEUS peak enhancement; providing differentiation between active and chronic bowel wall inflammation to improve selection between medical therapy and surgery.
炎症、纤维化和肌肉肥大导致克罗恩病患者的肠壁增厚，形成狭窄。超声剪切波弹性成像（SWE）可测量肠壁硬度。超声造影（CEUS）能独特地检测肠壁炎症。我们旨在将活体回肠克罗恩病的SWE与CEUS峰值增强以及炎症、纤维化和肌肉肥大的病理分级相关联。
在一项经机构审查委员会批准的前瞻性研究中，105例连续的回肠克罗恩病患者接受了超声检查。在肠壁厚度最大时（>4mm），进行SWE和CEUS检查。15例患者在平均71.0±66.9天的时间间隔内接受了回肠切除术。将炎症、纤维化和肌肉肥大的病理评分与SWE和CEUS测量结果进行比较。
接受手术和未接受手术患者的平均活体SWE速度分别为2.8±0.7和2.2±0.8m/s（P<0.01）。在所有回肠标本中，慢性炎症变化超过了活动性炎症变化（P<0.001）。CEUS峰值增强与纤维化（r=-0.59，P=0.02）和SWE速度测量值（r=-0.61，P=0.03）均呈负相关。狭窄肠段标本的平滑肌肥大比纤维化更明显，P<0.001。SWE与肌肉肥大之间存在中度相关性（r=0.59，P=0.02），SWE与纤维化评分之间无显著关系（P>0.05）。
平滑肌肥大导致的肠壁变硬会增加SWE测量值。我们报告了SWE与肌肉肥大的新关系，以及与CEUS峰值增强的负相关关系；这有助于区分活动性和慢性肠壁炎症，以改善药物治疗和手术治疗的选择。
