Rheumatology Department, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Radiology Department, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Muscle Nerve. 2019 Nov;60(5):549-557. doi: 10.1002/mus.26660. Epub 2019 Aug 20.
This study assesses the burden, distribution, and evolution of muscle inflammation and damage on MRI among subtypes of idiopathic inflammatory myopathy (IIM).
Musculoskeletal MRIs performed in 66 patients with IIM and 10 patients with non-IIM between 2009 and 2016 were retrospectively graded for muscle edema, fatty replacement (FR), and atrophy.
Immune-mediated necrotizing myopathy (IMNM) patients had severe and extensive lower limb muscle edema, FR, and atrophy. The pelvic muscles and adductors were significantly more affected than in patients with dermatomyositis and polymyositis. Inclusion body myositis (IBM) was characterized by marked anterior thigh involvement, which stabilized or progressed at follow-up imaging. Atrophy and FR grades improved over time in some non-IBM IIM patients.
Patients with IMNM and IBM have characteristic patterns of muscle MRI abnormalities that may allow them to be differentiated radiologically from other IIM subtypes. Muscle damage in non-IBM IIM may be reversible.
本研究评估了特发性炎性肌病（IIM）各亚型患者 MRI 上肌肉炎症和损伤的负担、分布和演变。
回顾性分析了 2009 年至 2016 年间 66 例 IIM 患者和 10 例非 IIM 患者的肌肉骨骼 MRI，对肌肉水肿、脂肪浸润（FR）和萎缩进行分级。
免疫介导的坏死性肌病（IMNM）患者下肢肌肉水肿、FR 和萎缩严重且广泛。骨盆肌肉和内收肌的受累程度明显高于皮肌炎和多发性肌炎患者。包涵体肌炎（IBM）的特征是大腿前部明显受累，随访时影像学表现稳定或进展。一些非 IBM IIM 患者的肌肉萎缩和 FR 分级随时间推移而改善。
IMNM 和 IBM 患者具有特征性的肌肉 MRI 异常模式，可能使他们能够在影像学上与其他 IIM 亚型区分开来。非 IBM IIM 中的肌肉损伤可能是可逆的。
