Role of contrast-enhanced ultrasound in evaluation of the bowel

Abstract

Contrast-enhanced ultrasound (CEUS) of the gastrointestinal tract provides vascular information helpful for characterizing masses and other pathologies in and around the bowel, similar to contrast applications in other solid organs. However, the use of microbubble contrast agents for the bowel provides additional unique contributions as it gives both subjective and objective information about mural and mesenteric blood flow, invaluable for the determination of disease activity in those many patients affected by inflammatory bowel disease (IBD). IBD is a lifelong chronic disease and has its peak age of onset in adolescence or young adult life. Today, we have moved away from treating patient’s symptoms and strive instead to alter the course of disease by obtaining mucosal healing. Expensive and aggressive biologic therapies and lack of agreement of patient’s symptoms with their disease activity and complications necessitate frequent imaging surveillance, which must be safe, readily available, inexpensive, and effective. Ultrasound with the benefit of contrast enhancement meets these requirements and is shown in meta-analysis to be equivalent to CT and MRI scans for these indications.Electronic supplementary materialThe online version of this article (10.1007/s00261-017-1399-6) contains supplementary material, which is available to authorized users.

Contrast‐enhanced ultrasound for quantification of tissue perfusion in humans

“…Background subtraction is essential in determining tissue perfusion. Contrast‐specific subtraction consists of subtraction of the native background signal, that is, the signal before microbubble infusion, from the maximal tissue intensity so that a microbubble‐only image is created . The background signal from surrounding tissues is determined by the selected gain and other ultrasound settings as well as tissue properties and may therefore differ per individual and per measurement.…”

Can Contrast-Enhanced Ultrasonography Document Both an Iatrogenic Bleeding and the Stop of the Bleeding? A Case Report

“…US can also be useful in the diagnostic workup of diverticulitis, with a sensitivity of 77-98% and a specificity of 80-90% [1]. CEUS is increasingly recommended as a reliable additional tool when differentiation on grayscale US is challenging, for instance in the differential diagnosis between phlegmon and abscess [2]. Moreover, when the abdominal collections can be confidently depicted, US and CEUS are considered the imaging techniques of choice to guide their percutaneous drainage, enabling both the detection of septations and loculations, and the real-time monitoring of the needle advancement [2][3][4].…”

“…Moreover, it can be used to guide percutaneous drainage of the abscess collections [1]. Recently, contrast-enhanced US (CEUS) has been reported to improve the US assessment of the bowel pathology, enabling to better evaluate and quantify the presence of bowel inflammation and its complications [2], as well as to guide more reliably and safely the percutaneous treatment [3]. However, abscess drainage carries an inherent risk of bleeding complications also with CEUS guidance, even though they are often self-limited and can usually be managed conservatively [3].…”

Imaging Inflammation and Infection in the Gastrointestinal Tract

“…To increase the accuracy of US in these and general IBD cases, contrast enhanced ultrasonography (CEUS) may be used. CEUS uses a intravenously applied microbubble contrast agent, such as sulfur hexafluoride, to show bowel wall enhancement and mesentery [144,145]. CEUS provides real-time information on the vascularity of the scanned area.…”

“…CEUS provides real-time information on the vascularity of the scanned area. Since IBD causes vascular alterations in affected areas, this information gives clinicians an understanding on IBD activity in the patient [144][145][146][147][148]. In general, CEUS appears to provide greater clinical certainty in evaluating IBD in patients.…”