Contrast-enhanced ultrasound could be a useful technique to monitor the activity of Crohn’s disease, according to a study in this month’s Radiology.
Contrast-enhanced ultrasound shows potential as an alternative to colonoscopy in the evaluation of Crohn’s disease, according to the authors. Tomás Ripollés, MD, from the department of radiology at Hospital Universitario Dr Peset in Valencia, Spain, sought to evaluate the effectiveness of visualization of vascularization at contrast material–enhanced ultrasonography for assessment of the activity of Crohn’s disease, with severity grade determined at endoscopy as the reference standard.
The researchers prospectively assessed 61 patients (median age, 36 years) who had Crohn’s disease and underwent both colonoscopy and ultrasound, including color Doppler and contrast-enhanced ultrasound.
To study the vascularization of the involved bowel loop in a region expected to be seen at colonoscopy, the contrast agent uptake was measured by using quantitative analysis of the enhancement in regions of interest. They also assessed measurement of contrast enhancement as the increase in wall brightness with respect to the baseline brightness.
Ripollés and colleagues found that the colonoscopy showed inflammatory lesions in 53 patients (mild disease, seven; moderate disease, 12; and severe disease, 34). Bowel wall thickness and grade at color Doppler ultrasound correlated with severity grade at endoscopy.
According to the researchers, mural contrast enhancement in patients with active disease at endoscopy was markedly increased in comparison with enhancement in patients with inactive disease. Multivariate logistic regression analysis revealed that an increase in wall brightness was a significant and independent variable predictive of severity grade at endoscopy.
Investigators said that the threshold brightness value of percentage of increase of 46 percent had a sensitivity and specificity of 96 percent and 73 percent, respectively, in the prediction of moderate or severe grade for inflammation at endoscopy.
Ripollés and colleagues concluded that quantitative measurements of bowel enhancement obtained by using contrast-enhanced ultrasound correlate with severity grade determined at endoscopy. The capability of contrast-enhanced ultrasound to distinguish active from inactive Crohn’s disease may make it a viable noninvasive alternative to colonoscopy, they concluded.