P094 Prediction of patency capsule retention by MR Enterography in patients with known Crohn's disease:
M.M. Amitai*1, N. Rozendorn1, E. Klang1, A. Lahat2, U. Kopylov3, D. Yablecovitch2, S. Ben-Horin2, R. Eliakim2
1Sheba Medical Center, Department of Diagnostic Imaging, Tel Hashomer, Israel, 2Chaim Sheba Medical Center, Gastroenterology, Ramat Gan, Israel, 3Sheba Medical Center, Gastroenterology, Tel Hashomer, Israel
The main complication of capsule endoscopy (CE) in Crohn's disease (CD) patients is capsule retention. Evaluation of small bowel patency is recommended before CE administration by using cross-sectional imaging or patency capsule (PC). Our aim was to evaluate the ability of magnetic resonance enterography (MRE) to predict PC retention in CD patients, and to identify the most predictive imaging features for PC retention.
Fifty seven patients underwent MRE followed by PC. A radiologist blinded to the PC Results gave a positive or negative prediction for PC retention based on the MRE and thereafter all patients swallowed a PC. Diseased segments (DS) on the MRE were evaluated for the following imaging features: mean number of segments, stenosis and prestenotic dilatations, maximal stenosis length, maximal wall thickness and ***presence of enhancement.
The association of these imaging features with the risk of PC retention was evaluated.
The radiologist gave a positive prediction of PC retention in 30/57 patients. Actual PC retention occurred in 13/57 patients and was predicted by MRE in 12/13 cases. The sensitivity, specificity, positive and negative predictive values (PPV/NPV) for prediction of PC retention were 92.3%, 59%, 40% and 96.3% respectively.
Diseased segments were found in 45 /57 patients. The mean maximal stenosis length (9.7 cm vs 7 cm, p=0.04) and the mean number of prestenotic dilatations (2 vs 1.1, p=0.02) were significantly associated with PC retention. One case of symptomatic PC retention occurred in the study which resolved with steroid treatment. No cases of CE retention occurred.
MRE has high NPV and sensitivity but low PPV and specificity for PC retention.
Capsule retention suggested by MRE should not preclude performance of PC to determine the feasibility and safety of diagnostic CE. Longer stenosed strictures and higher number of prestenotic dilatations on MRE were significantly associated with PC retention.
RE, SBH- equal contribution
The study was sponsored by the Helmsley Charitable trust