Significance of Abdominal Ultrasound in Inflammatory Bowel Disease

Abstract

Transabdominal ultrasound is most commonly used to examine the liver, hepatobiliary-pancreatic and urogenital tract. Its use for imaging the intestinal tract is less well established and has been considered more difficult in the past. Improvements in technology and increasing experience with sonographic findings in a variety of intestinal diseases including inflammatory bowel disease (IBD), however, have contributed to firmly establishing the role of ultrasound as a clinically important, non-invasive and widely available imaging modality. In addition, newer techniques such as harmonic imaging and contrast-enhanced ultrasound have recently gained attention. Transabdominal ultrasound is clinically useful in the initial diagnosis of IBD by evaluating bowel wall thickness and surrounding structures including peri-intestinal inflammatory reaction, extent and localization of involved bowel segments and detection of extraluminal complications such as fistula, abscesses, carcinoma and ileus. Transabdominal ultrasound is currently accepted as a clinically important first-line tool in assessing patients with Crohn’s disease irrespective of their clinical symptoms and/or disease activity. It helps to better characterize the course of the disease in individual patients and can guide therapeutic decisions. The topic of this review is to provide an updated overview of the role of transabdominal ultrasound in IBD including Crohn’s disease, ulcerative colitis, tuberculosis and neutropenic colitis while summarizing the results of recent studies with special reference to sensitivity/specificity in detecting the disease and sonomorphologic features to evaluate disease activity and its luminal and extraluminal complications.

The importance of intestinal ultrasound and elastographic techniques in inflammatory bowel diseases

“…The role of abdominal US in UC is not as well defined as in CD, mostly because the bowel wall is not always thickened, the inflammation is limited to the mucosa and the bowel wall stratification is preserved in most of the subjects [38,88].…”

“…Unlike CD, thickening of the intestinal wall is not constantly correlated with the clinical activity of the disease in UC [88]. While in cases of mild relapse there is no or inconsistent concordance between the bowel wall thickness and clinical and endoscopic scores, in moderate or severe UC, bowel wall thickness can be used as a surrogate for colonoscopy and CRP for monitoring the course of the disease and the response to therapy [89,90].…”

“…The other US parameters of IBD, such as the intestinal wall vascularization and fibrofatty proliferation, are less visible in UC compared to CD [24,88]. However, in severe active forms of UC, extramural signs such as fibrofatty proliferation, peritoneal fluid, and even "mesenteric lines" can be visible, even though most of the time, this condition is largely limited to the mucosa [38].…”

Ultrasound Measurement in M Mode of Peristalsis and Gastric Emptying

“…Clinical trans-abdominal ultrasound (US) studies have been used in hepatobiliary-pancreatic and liver examination, and recently in bowel inflammation (Dietrich et al 2009), nevertheless, for GI tract assessments; the use of US technique is still controversial. Fortunately, technology advances and recent results obtained by echography in a wide variety of GI ills (Kusunoki et al 2010), this suggest that the US technique is a powerful diagnostic tool for carrying out gastric studies and monitoring the GI tract (Newell et al 1993).…”

Is This Stricture Inflammatory?

“…Ultrasound has been shown to be useful for the clinical management of CD [8][9][10][11][12] . Ultrasound results have been shown to be predictive for the disease behavior [10][11][12][13][14][15][16] , which is of importance in the context of the study presented in this issue of Digestion .Bowel wall thickness has been the most important readout in studies on the diagnostic value of ultrasound in IBD patients [10,11,[16][17][18][19] . In addition to simple morphometry, contrast-enhanced ultrasound or splanchic artery blood flow measurements have been applied with mixed results [12,[20][21][22][23][24][25] .…”