Diffusion‐weighted magnetic resonance imaging is useful for assessing inflammatory myopathies

• Published in: Muscle & nerve Vol. 59; no. 5; pp. 555 - 560
• Main Authors: Faruch, Marie, Garcia, Ana Isabel, Del Amo, Montse, Pomes, Jaume, Isern, Jaime, González, Sergio Prieto, Grau, Josep María, Milisenda, José César, Tomas, Xavier
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.05.2019; Wiley Subscription Services, Inc
• Subjects: diffusion magnetic resonance imaging; Diffusion rate; Edema; Image acquisition; Inflammation; inflammatory myopathy; Magnetic resonance imaging; Medical imaging; Muscles; muscular disease; NMR; Nuclear magnetic resonance; whole body imaging; Edema; Whole body Imaging; Inflammatory myopathy; Diffusion Magnetic Resonance Imaging; Muscular disease
• ISSN: 0148-639X; 1097-4598; 1097-4598
• DOI: 10.1002/mus.26438

ABSTRACT Introduction: Short tau inversion recovery (STIR) sequences in whole‐body MRI are usually used for detecting muscle edema (ME) in inflammatory myopathies. We evaluated b‐value 800 diffusion‐weighted imaging (b800 DWI).Methods: Two radiologists independently and a consensus reader retrospectively reexamined 60 patients with inflammatory myopathies and 15 controls. For each participant, 78 muscles were analyzed with 3 sets of imaging acquisitions: T1‐weighted (T1) turbo spin echo and STIR; T1 and DWI; and T1, STIR and DWI. Mean edema per patient was compared between sequences. Agreement was evaluated. Results: Diffusion‐weighted imaging detected more ME compared with STIR (P < 0.001). Agreement between readers was better with both sequences (k = 0.94) than with b800 DWI (k = 0.89) or STIR (k = 0.84) alone. Discussion: Diffusion‐weighted imaging is a valuable add‐on for the study of inflammatory myopathies. Muscle Nerve 59:555–555, 2019