The Characteristics of Imaging Patterns on Whole-body Magnetic Resonance Imaging of Anti-signal Recognition Particle Antibody-positive Immune-mediated Necrotizing Myopathy

Whole-body MRI in anti-SRP patients revealed a characteristic edema pattern with an affinity for specific muscles of the shoulders and pelvis with a radial distribution, with edema severity corresponding to clinical severity, particularly respiratory function. Pretreatment with steroids reduced edema, indicating the efficacy of this treatment.