P0600 Do GI Quant small bowel motility values correlate with reported MR enterography findings in Crohn’s disease?
Authors: Macpherson S , Ballantyne S , Brownson E , Campbell I , Robertson A , Hall M , Menys A , Seenan J P , MacDonald J 
Published: January 2025

Abstract

Background
Cine sequences in MR enterography (MRE) allow assessment of small bowel (SB) motility, which inversely correlates with disease activity and symptoms in Crohn’s disease (CD)1,2. GI Quant (GIQ) is a tool that uses cine sequences to provide an objective motility map score (MM) for diseased small bowel loops. This can be tracked through time using identified regions of interest (ROI).
We looked at whether GIQ MM score for the most diseased loop of SB correlated with how radiology reports commented on overall disease.

Methods
- CD patients with &gt;1 MRE from 2015-2022 were identified retrospectively via the local inflammatory bowel disease database and their MRE images were loaded onto GIQ software.
- ROIs were independently drawn by 2 gastrointestinal radiologists around diseased loops of SB, generating a MM value for each region.
- Each MRE report was reviewed and compared to MM value.
- Change in MM and scan report over time was also examined. Change in scan report categorsised as no change/ worsening/ improving.
- Two radiologists’ assessment of size and MM for each ROI were compared to assess inter-observer variability.

Results
- Scans from 45 patients (23 male, 22 female) were included (90 MRE in total). Age range 15-64.
- Of 90 MREs, 14 were reported as normal and 76 abnormal, 31 showing active inflammation, 6 fibrostenotic and 38 both.
- Of normal scans, mean MM was 262.6 (range 138.6-423.2). For abnormal scans, mean was 224.9 (range 74.8-454.6)
- MM did not discriminate between normal and abnormal scans (p=.298), presence of active disease (p.309), fibrostenotic disease (p.892) or hold-up (p.736) on MRE.
- Change in MM between scans was not associated with change in disease activity.
- The same segments of SB disease were measured independently by each radiologist in 81/90 (90%) MREs.
- There was positive correlation between both the area of ROI drawn (r=.73, p&lt;.001) and MM of each segment identified (r=.889, p&lt;.001).

Conclusion
GIQ has previously been validated as a tool for small bowel CD assessment, with GIQ SB motility scores correlating with CD activity based on imaging scoring systems for disease activity eg. MARIA2. However, our retrospective study indicates that the motility score generated for a single diseased loop of SB does not correlate well with the overall MRE report. The reasons for this are not clear and may reflect limitations in the subjective and non-standardised nature of reporting these studies in our centre, and the fact that MM is assessing a single diseased bowel loop whilst the MRE report parameters deal with the whole SB. We plan to correlate our findings with clinical parameters.
Our study demonstrated strong inter-observer agreement between the two radiologists, in-keeping with other studies.

References
1)Gollifer RM, Menys A, Plumb A, Mengoudi K, Puylaery C, Tielbeek JA et al. Automated versus subjective assessment of spatial and temporal MRI small bowel motility in Crohn’s disease. Clin Radiol . 2019 Oct;74(10):814.e9-814.e19.
2)Menys A, Puylaery C, Tutein Nolthenius C, Plumb A, Makanyanga J, Tielbeek J et al.Quantified Terminal Ileal Motility during MR Enterography as a Biomarker of Crohn Disease Activity: Prospective Multi-Institution Study 2018 Nov;289(2):428-435. doi: 10.1148/radiol.2018180100.