Ultrasound of the Intestine in Crohn's Disease: Wall Thickness and Disease Activity
The Role of GIUS in Assessing Crohn's Disease
Gastrointestinal ultrasound (GIUS) holds a recognized place in the diagnosis of inflammatory bowel diseases according to EFSUMB guidelines (Maconi et al., Ultraschall Med, 2018). Bowel wall thickness is the main quantitative parameter for assessing the extent and activity of Crohn's disease; wall thickening has clinical significance and correlates with inflammation activity (Maconi G. et al., Am J Gastroenterol 1996; Mayer D. et al., Z Gastroenterol 2000).
Wall Thickness as an Activity Parameter
Sonographic measurement of thickened wall segments is used as a quantitative parameter of activity in inflammatory bowel diseases (Mayer D. et al., Z Gastroenterol 2000). Specific threshold values for thickness in the provided fragments are not given [clarify].
Doppler Assessment of Vascularization
Doppler study data correlate with tissue vascularization and inflammation in surgical pathological samples of patients with Crohn's disease of the small intestine (Sasaki T. et al., BMC Research Notes 2014). This allows the use of Doppler as a marker of inflammatory activity.
Contrast-Enhanced Ultrasound (CEUS)
Mucosal microvascularization of the ileum, quantitatively assessed by CEUS, correlates with disease activity (De Franco A. et al., Radiology 2012). Quantitative CEUS parameters play a role in determining Crohn's disease activity (Medellin-Kowalewski A. et al., AJR 2016). CEUS data correlate with severity according to endoscopy data (Ripolles T. et al., Radiology 2009).
Differentiation of Inflammation and Fibrosis
CEUS and Power Doppler are used to differentiate hypervascularized and hypovascularized obstructions in patients with Crohn's disease (Kratzer W. et al., J Ultrasound Med 2002), as well as to assess inflammatory and fibrotic strictures (Schirin-Sokhan R. et al., Digestion 2011). Real-time elastography is used to identify fibrotic tissue in stricturing Crohn's disease (Baumgart DC et al., Radiology 2015).
Frequently asked questions
What is the main ultrasound parameter reflecting Crohn's disease activity?
Bowel wall thickness is the main quantitative parameter; its thickening correlates with the extent and activity of the disease (Maconi G. et al., 1996; Mayer D. et al., 2000).
What specific threshold values for wall thickness should be used?
Specific numerical thresholds are not indicated in the provided sources [clarify].
What does Doppler study provide in Crohn's disease?
Doppler findings correlate with tissue vascularization and inflammation in surgical samples in Crohn's disease of the small intestine (Sasaki T. et al., 2014).
How does CEUS help in assessing activity?
Mucosal microvascularization in CEUS quantitatively correlates with disease activity (De Franco A. et al., 2012) and with severity according to endoscopy (Ripolles T. et al., 2009).
Can inflammatory stenosis be distinguished from fibrotic stenosis?
Yes, CEUS and Power Doppler are used to differentiate hyper- and hypovascularized obstructions (Kratzer W. et al., 2002), as well as elastography to identify fibrosis (Baumgart DC et al., 2015).