Monitoring Crohn's disease with Magnetic resonance index of activity (MaRIA) and Clermont score: correlation with SES-CD and fecal calprotectin

Congress:

ECR 2020

Poster Number:

C-14790

Type:

Scientific Exhibit

Keywords:

MR-Enterography, Small bowel, Gastrointestinal tract, Abdomen, GI Tract, Outcomes analysis, Image verification, Inflammation, Prospective, Diagnostic or prognostic study, Performed at one institution

Authors:

F. A. Carpagnano, A. Lacanna, M. R. Petrera, A. N. Cintoli, L. P. Stoppino, R. Vinci, L. Macarini; foggia/IT

DOI:

10.26044/ecr2020/C-14790

DOI-Link:

https://dx.doi.org/10.26044/ecr2020/C-14790

Table 1: TABLE 1:MRE protocol

Table 2: TABLE 2: Scoring sheet for SES-CD

Table 3: TABLE 3: Categories of the radiological-biological response

Methods and materials

Patients population

We performed a prospective single centre study of 36 patients with biopsy-proven diagnosis of active CD (22 males and 14 females; median age of 25,8 ys; age range, 18–47). All patients underwent ileo-colonoscopy, MRI at baseline and 26 weeks after anti - TNF therapy. Fecal calprotectin levels were collected before and after treatment.

Inclusion criteria were as follows: age older than 18 years; moderately or severely active CD (as shown by a SES-CD score > 7 points); elevated fecal calprotectin level (>250 μg/g); and at least 6 months of follow-up after the beginning of therapy with biologic drugs.

Data Acquisition

All MRE examinations were performed in the supine position with a 1.5 T magnet, with a phased-array-16-elements coil. 1 hour prior to MRI, all patients received orally 1000-1500ml of iso-osmotic PEG solution. A coronal T2 scan was performed 30 minutes after oral contrast administration in order to ensure an adequate intestinal distension (greater or equal to 15 mm in diameter) and continue the examination, after the N-butylscopolaminei.m. injection (Table 1).

Image analysis

Two radiologists independently reviewed the anonymized MRE examinations. To allow comparison with endoscopic score (Table 2), the same division into segments was considered. The small and large bowel were examined on the basis of the following criteria: bowel wall thickness (mm), presence of mucosal ulcers, presence of mural oedema, presence of enlarged regional mesenteric lymph nodes, presence of fistula or abscess, and relative contrast enhancement (RCE) of the intestinal wall. Quantitative measurements of wall signal intensity (WSI) were obtained from the areas with the greatest thickening [region of interest (ROI)] before and after intravenous injection of gadolinium (70 s). RCE was calculated according to the following formula: RCE = [(WSI postgadolinium − WSI pregadolinium)/(WSI pregadolinium)] × 100 × (SD noise pregadolinium/SD noise postgadolinium). As defined by Rimola et al. [3, 4] for measurement of therapeutic response by means of MRI and to allow comparison with the reference standard (SES-CD), the MaRIA in each segment was calculated according to the following formula: 1.5 × wall thickening (mm) + 0.02 × RCE (relative contrast enhancement) + 5 × oedema + 10 × ulcers. The overall MaRIA was calculated as the mean of the MaRIA scores examined segments.

The ADC was assessed on the DWI, and the map determined by averaging 3 ADC values. Then, the Clermont score was calculated according to the following formula: 1.646 × bowel thickness − 1.321 × ADC + 5.613 × edema + 8.306 × ulceration + 5.039 [5]. The overall Clermont score was calculated as the mean of the results in examined segments.

Response Assessment

In order to quantify disease activity, the SES-CD, the MaRIA and the Clermont scores were calculated at baseline and 26 weeks after treatment initiation. Mucosal healing was defined as the absence of mucosal ulcerations at week 26 in patients who had mucosal lesions endoscopically confirmed at baseline [6]. The endoscopic response was defined as a decrease from baseline in SES-CD score of at least 5 points and at least 50% [7] with a complete endoscopic remission (MH) when SES-CD score ≤ 2 [8]. According to MRI examinations’ results and fecal calprotectin measurements, three categories were identified to define the radiological-biological response as reported in Table 3.

Statistical Analysis

Quantitative variables are given as means and standard deviation (SD) and proportions are expressed as percentages and 95% confident intervals (CIs). Differences in quantitative measures were tested by Student’s test. The associations between continuous variables were evaluated with Pearson’s bivariate correlation analysis. To determine the best cut-off value of the MRE and DWI scores for predicting endoscopic remission (SES-CD score ≤ 2) receiver operating characteristic (ROC) curves were calculated. Inter-observer agreement between paired evaluations of MR by two radiologists was performed with Pearson correlation coefficient.