The reproducibility of skeletal muscle signal intensity on routine magnetic resonance imaging in Crohn's disease

• Published in: Journal of gastroenterology and hepatology Vol. 35; no. 11; pp. 1902 - 1908
• Main Authors: Spooren, Corinne E.G.M., Lodewick, Toine M., Beelen, Evelien M.J., Dijk, David P.J., Bours, Martijn J.L., Haans, Jeoffrey J., Masclee, Ad A.M., Pierik, Marie J., Bakers, Frans C.H., Jonkers, Daisy M.A.E.
• Format: Journal Article
• Language: English
• Published: Australia Wiley Subscription Services, Inc 01.11.2020; John Wiley and Sons Inc
• Subjects: Adult; Cirrhosis; Clinical Gastroenterology; Computed tomography; Crohn Disease - complications; Crohn Disease - diagnostic imaging; Crohn Disease - mortality; Crohn Disease - surgery; Crohn's disease; Crohns disease; Diagnosis; disease outcome; Female; Gastroenterology; Humans; IBD; Intestine; Liver cancer; Liver cirrhosis; Magnetic Resonance Imaging; Male; Muscle, Skeletal - diagnostic imaging; Musculoskeletal system; myosteatosis; Prognosis; Reproducibility; Reproducibility of Results; Sarcopenia - diagnostic imaging; Sarcopenia - etiology; Skeletal muscle; Survival Rate; Time Factors; Treatment Outcome; disease outcome; IBD; myosteatosis
• ISSN: 0815-9319; 1440-1746
• DOI: 10.1111/jgh.15068

Background and Aim Myosteatosis is a prognostic factor in cancer and liver cirrhosis. It can be determined noninvasively using computed tomography or, as shown recently, by magnetic resonance (MR) imaging. The primary aim was to analyze the reproducibility of skeletal muscle signal intensity on routine MR‐enterographies, as indicator of myosteatosis, in Crohn's disease (CD) and to explore the association between skeletal muscle signal intensity at diagnosis with time to intestinal resection. Methods CD patients undergoing MR‐enterography within 6 months from diagnosis and having a maximum of 5 years follow‐up were included. Skeletal muscle signal intensity was analyzed on T1‐weighted fat‐saturated post‐contrast images. Intra‐observer and inter‐observer reproducibilities were assessed by intra‐class correlation coefficient and Cohen's kappa. Intra‐observer and inter‐observer variabilities were determined by Pearson correlation coefficient and displayed by Bland–Altman plots. Time to intestinal resection was studied by Kaplan–Meier analysis. Results Median time between diagnosis and MR‐enterography was 5 weeks (inter‐quartile range 1–9) in 35 CD patients. Skeletal muscle signal intensity showed good intra‐class correlation and substantial agreement (for intra‐observer, intraclass correlation coefficient = 0.948, κ = 0.677; and inter‐observer reproducibility, intraclass correlation coefficient = 0.858, κ = 0.622). Resection free survival was shorter in the low skeletal muscle signal intensity group (P = 0.037). Conclusion Skeletal muscle signal intensity on routine MR‐enterographies is reproducible and was associated with unfavorable disease outcome, indicating potential clinical relevance.