Feasibility of magnetic resonance elastography of mesenteric adipose tissue in Crohn's disease.

Background: Although there is growing evidence that functional involvement and structural changes of mesenteric adipose tissue (MAT) influence the course of Crohn's disease (CD), its viscoelastic properties remain elusive. Therefore, we aimed to investigate the viscoelastic properties of MAT in CD using magnetic resonance elastography (MRE), providing reference values for CD diagnosis.

Methods: In this prospective proof-of-concept study, 31 subjects (CD: n=11; healthy controls: n=20) were consecutively enrolled in a specialized care center for inflammatory bowel diseases (tertiary/quaternary care). Inclusion criteria for the CD patients were a clinically and endoscopically established diagnosis of CD based on the clinical record, absence of other concurrent bowel diseases, scheduled surgery for the following day, and age of at least 18 years. Diagnoses were confirmed by histological analysis of the resected bowel the day after MRE. Subjects were investigated using MRE at 1.5-T with frequencies of 40-70 Hz. To retrieve shear wave speed (SWS), volumes of interest (VOIs) in MAT were drawn adjacent to CD lesions (MAT) and on the opposite side without adjacent bowel lesions in patients (MAT) and controls (MAT). The presented study is not registered in the clinical trial platform.

Results: A statistically significant decrease in mean SWS of 7% was found for MAT MAT (0.76±0.05 0.82±0.04 m/s, P=0.012), whereas there was a nonsignificant trend with an 8% increase for MAT MAT (0.82±0.07 0.76±0.05 m/s, P=0.098) and no difference for MAT MAT. Preliminary area under the receiver operating characteristic curve (AUC) analysis showed diagnostic accuracy in detecting CD to be excellent for SWS of MAT [AUC =0.82; 95% confidence interval (CI): 0.64-0.96] but poor for SWS of MAT (AUC =0.52; 95% CI: 0.34-0.73).

Conclusions: This study demonstrates the feasibility of MRE of MAT and presents preliminary reference values for CD patients and healthy controls. Our results motivate further studies for the biophysical characterization of MAT in inflammatory bowel disease.