[Correlation between contrast-enhanced ultrasound parameters and Crohn's disease activity]

Objective: By investigating the correlation between quantitative parameters of contrast enhanced ultrasound (CEUS) and commonly used activity assessment indicators of Crohn's disease (CD), and comparing the predictive power of laboratory inflammatory indicators with CEUS on Crohn's disease (CD), the significance of CEUS was evaluated. Methods: A case-control study. From October 2019 to December 2021, the clinical data of 67 patients with CD who were diagnosed by endoscopy and underwent contrast-enhanced ultrasonography were retrospectively analyzed in the First Affiliated Hospital with Nanjing Medical University, and their routine ultrasound and CEUS parameters, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fecal calprotectin (FC), Crohn's disease activity index (CDAI) and simplified endoscopic score for Crohn's disease (SES-CD) were collected. Using SES-CD as the standard, the patients were divided into a remission group and an active group, and the correlation of laboratory inflammatory indexes and contrast-enhanced ultrasound parameters with CDAI and SES-CD were evaluated. Besides, the ROC curve was used to analyze the predictive efficacy of each index on CD endoscopic activity. Results: A total of 67 patients were included in this study. According to the SES-CD score, there were 17 patients in the remission group and 50 patients in the active group. Except for the coefficient of the enhancement wash in slope and time to peak (TTP), the peak intensity (PI), area under the angiography curve, and laboratory inflammatory indexes were significantly different between the two groups (P<0.05), which also showed a moderate positive correlation with CDAI and SES-CD (P<0.05). ROC analysis showed that among the non-invasive indicators, PI and area under the angiography curve had the highest AUCs for predicting CD endoscopic activity, which were 0.912 and 0.891, respectively; with SES-CD taking >3 as the cut-off value, the corresponding sensitivities were 78.0% and 72.0%, with specificities of 100.0% and 94.1%, respectively. Conclusion: CEUS can objectively and repeatedly evaluate the disease activity of CD patients, and has great clinical application value, which can be used as a reliable imaging method for diagnosis and follow-up of patients with Crohn's disease.