Intravenous Contrast-Enhanced Ultrasound for Assessing and Grading Postoperative Recurrence of Crohn's Disease

The aim was to investigate the contribution of contrast-enhanced ultrasound (CEUS) to improve the results of US in the evaluation of recurrence in postsurgical Crohn's disease (CD) and establish its role in the assessment of the severity.

Anastomotic site was assessed in 108 postsurgical CD patients with B-mode, color Doppler and CEUS. Bowel wall thickness (WT), transmural complications or stenosis, color Doppler grade, and bowel wall contrast enhancement (BWCE)-using time-intensity curves-were correlated with endoscopic Rutgeerts score. A receiver operating characteristic (ROC) curve was built to establish the best cutoff to predict recurrence and the severity. A US scoring system was elaborated in order to determine the grade of recurrence.

Ileocolonoscopy detected recurrence in 90 (83.3%) subjects and severe recurrence in 62. WT ≥ 3 mm had an accuracy of 90.7% in the detection of endoscopic recurrence. The combination of parameters-WT ≥ 3 mm and BWCE (≥ 46%)-demonstrated similar accuracy (90.7%). A WT ≥ 5 mm showed the best specificity (100%) for the diagnosis of recurrence and a WT ≥ 6 mm the best specificity (95.7%) for the detection of severe recurrence. The combination of sonographic parameters-WT ≥ 6 mm or WT between 5 and 6 mm with BWCE ≥ 70%, or complications-obtained the best results grading the recurrence (sensitivity, specificity, and accuracy of 90.3%, 87%, and 88.9%, respectively).

US shows high sensitivity and specificity for the diagnosis of postsurgical recurrence. When combined with CEUS, it can improve the detection of severe recurrence.