Body Imaging – Bowel

CEUS is a safe, versatile and reliable tool for imaging the bowel in the following clinical contexts: 

• To detect, evaluate and objectively quantify the presence of bowel inflammation and its complications in patients with IBD
• To differentiate the nature of inflammatory masses found in patients with IBD
• To differentiate strictures in IBD
• To monitor response to IBD therapy

CEUS uses ultrasound contrast agents (UCAs)  to improve the clarity and reliability of conventional ultrasound scans. UCAs are comprised of liquid suspensions of biodegradable gas-filled microspheres (sometimes called “microbubbles”). When they are injected into a patient’s arm vein during an ultrasound exam, they flow through the body’s microcirculation without impediment, and are metabolized and expelled from the body within minutes.

Imaging is performed with patient is a supine position. The transducer is placed at the region of interest (ROI) selected on the initial grayscale assessment. The abnormal bowel segment is evaluated in a sagittal orientation to minimize out-of-plane effects of respiratory motion and to facilitate generation of quality TIC allowing for quantification analysis. After contrast is injected through the patient’s IV, a continuous acquisition is initiated, even before the arrival of the first bubble in the field of view, and lasting for 2 min with no motion of the transducer. Most ultrasound equipment will allow for initial evaluation of the quantification curves at the bedside to assess technical quality of the time–intensity curve and to obtain preliminary results. If CEUS fails, or is technically inadequate, a second contrast injection may be performed, after a several minute delay.

CONTRAST AGENT DOSING
Dependence on transducer and instrumentation, body habitus. In general, twice the dose used for liver imaging is perfect for evaluation of the bowel. For the majority of adult patients, a dose of 3.0-4.8 ml Lumason; Definity 0.4-0.8ml; Optison inadequate literature.

• Barr, Richard G., et al., Society of Radiologists in Ultrasound (SRU):  Contrast-enhanced Ultrasound—State of the Art in North America Ultrasound Quarterly: September 2020 – Volume 36 – Issue 4S – p S1-S39 doi: 10.1097/RUQ.0000000000000515
• Piscaglia, F., et al., The EFSUMB Guidelines and Recommendations on the Clinical Practice of Contrast Enhanced Ultrasound (CEUS): update 2011 on non-hepatic applications. Ultraschall Med, 2012. 33(1): p. 33-59.
• Sidhu PS., et.al. The EFSUMB Guidelines and Recommendations for the Clinical Practice of Contrast-Enhanced Ultrasound (CEUS) in Non-Hepatic Applications: Update 2017. Ultraschall in Med 2018; 39: e2–e44.

Koutroubakis, I.E., et al., Role of angiogenesis in inflammatory bowel disease. Inflamm Bowel Dis, 2006. 12(6): p. 515-23.

Danese, S., et al., Angiogenesis as a novel component of inflammatory bowel disease pathogenesis. Gastroenterology, 2006. 130(7): p. 2060-73.

De Franco, A., et al., Ileal Crohn disease: mural microvascularity quantified with contrast-enhanced US correlates with disease activity. Radiology, 2012. 262(2): p. 680-8.

Wilkens R, P.P., Wilosn S, CEUS of the Bowel in Inflammatory Bowel Disease, in Contrast-Enhanced Ultrasound. 2013, International MEdical Publishers: London. p. 222-229.

Greis, C., Quantitative evaluation of microvascular blood flow by contrast-enhanced ultrasound (CEUS). Clin Hemorheol Microcirc, 2011. 49(1-4): p. 137-49.

Ripolles, T., et al., Crohn disease: correlation of findings at contrast-enhanced US with severity at endoscopy. Radiology, 2009. 253(1): p. 241-8.

Migaleddu, V., et al., Inflammatory activity in Crohn’s disease: CE-US. Abdom Imaging, 2011. 36(2): p. 142-8.

Quaia, E., et al., Time-Intensity Curves Obtained after Microbubble Injection Can Be Used to Differentiate Responders from Nonresponders among Patients with Clinically Active Crohn Disease after 6 Weeks of Pharmacologic Treatment. Radiology, 2016. 281(2): p. 606-616.

Lu, C., et al., Ultrasound Shear Wave Elastography and Contrast Enhancement: Effective Biomarkers in Crohn’s Disease Strictures. Inflamm Bowel Dis, 2017. 23(3): p. 421-430.

Schirin-Sokhan, R., et al., Assessment of inflammatory and fibrotic stenoses in patients with Crohn’s disease using contrast-enhanced ultrasound and computerized algorithm: a pilot study. Digestion, 2011. 83(4): p. 263-8.

Medellin-Kowalewski, A., et al., Quantitative Contrast-Enhanced Ultrasound Parameters in Crohn Disease: Their Role in Disease Activity Determination With Ultrasound. AJR Am J Roentgenol, 2016. 206(1): p. 64-73.