Purpose: To assess the value of small bowel wall vascularity after microbubble contrast agent injection in evaluating the therapeutic effectiveness of specific anti-inflammatory treatment in patients with Crohn's disease.
Materials and methods: Fifteen patients (7 male and 8 female; mean age+/-SD, 40 years+/-6) with a biopsy-proven diagnosis of Crohn's disease--Crohn's disease activity index (CDAI)>150 (n=12 patients) or <150 (n=3)--involving the terminal loop of the small bowel (wall thickness>5 mm) were included. In each patient the terminal loop was scanned by contrast-enhanced ultrasound (CEUS) after sulfur hexafluoride-filled microbubble injection before and after 6-month anti-inflammatory treatment. The vascularity of the terminal loop was quantified in gray-scale levels (0-255) by a manually drawn ROI encompassing the thickened bowel wall and it was correlated with CDAI.
Result: Before the beginning of the specific treatment all patients revealed diffuse transparietal contrast enhancement after microbubble injection, except for 3 patients who revealed contrast enhancement limited to the submucosa. In 13 patients the slope of the first ascending tract and the area under the enhancement curve were significantly lower after anti-inflammatory treatment (P<0.05; Wilcoxon test) with a significant correlation with the CDAI score (rho=0.85, P<0.05). In 2 patients no significant vascularity changes were found even though a mild reduction of CDAI score was identified (from 200 to 150 gray-scale levels).
Conclusion: CEUS is a useful method to assess the therapeutic effectiveness of specific medical anti-inflammatory treatment in patients with Crohn's disease.