Application of conventional ultrasound and contrast-enhanced ultrasound in the diagnosis of Crohn′s disease

Objective To explore the value of conventional ultrasound and contrast-enhanced ultrasound (CEUS) in the diagnosis of Crohn′s disease (CD). Methods From December 2012 to June 2015, totally 19 patients with CD were examined with conventional ultrasound and CEUS in Department of Ultrasound, Jinling Hospital, Medical School of Nanjing University. All patients were confirmed by endoscope and surgical pathology, including 12 cases of active CD and 7 cases of quiescent CD. The characteristics were analyzed and the quantitative parameters of time-to-peak (TTP) and peek intensity (PI) were gained according to the time-intensity curve (TIC). The difference of TTP and PI between active CD and quiescent CD was compared by Wilcoxon rank sum test. Results In these 19 patients, conventional ultrasound revealed stiff and thickened bowel walls with loss of normal peristalsis, the layers had ill-defined internal margins, and color Doppler identified the increased vascularization in mural or extra-visceral. In CEUS, the enhancement patterns of submucosal prevalent enhancement (5 cases) and complete transmural enhancement starting from mucosa and involving the entire bowel wall (7 cases) were generally related to active CD (12 cases), while complete transmural enhancement starting from perivisceral vessels and involving the entire bowel wall (5 cases) and low or absent enhancement (2 cases) were generally related to quiescent CD (7 cases). The quantitative analysis of TIC showed patients with active CD presented a reduced TTP enhancement and an increased PI in comparison to patient with quiescent CD [(8.33±0.92) s vs. (10.62±1.61) s, (27.67±1.61) dB vs. (25.48±1.49) dB] , and there was statistically difference between them (Z=-2.537, -2.451, both P<0.05). Conclusions Conventional ultrasound and CEUS is useful in diagnosing CD. In addition, CEUS is valuable in the evaluation of CD activity. Key words: Ultrasonography; Contrast media; Crohn disease; Diagnosis