Localized scleroderma: anatomic MRI findings of morphea with inter-reader analysis

Area of Science:

• Musculoskeletal Radiology
• Dermatology
• Medical Imaging

Background:

• Localized scleroderma (morphea) can affect deeper tissues, leading to significant musculoskeletal complications.
• Accurate characterization of morphea's extent is crucial for effective management and treatment planning.

Purpose of the Study:

• To detail musculoskeletal lesions in localized scleroderma (morphea) using Magnetic Resonance Imaging (MRI).
• To assess the reliability of MRI findings among different readers for diagnosing morphea.

Main Methods:

• A retrospective analysis of 49 patients diagnosed with various subtypes of morphea was conducted.
• Three musculoskeletal radiologists evaluated MRI scans, assessing involvement of skin, fat, fascia, muscle, nerve, joint, and bone, differentiating superficial from deep lesions.
• Inter-reader reliability was quantified using weighted Conger's Kappa and Intraclass Correlation Coefficient.

Main Results:

• MRI revealed superficial lesions in 63% of patients and deep lesions in 37%.
• Common findings included skin and fascial thickening/edema, fat atrophy, and notably, muscle edema and joint/bone involvement in deep lesions.
• Good inter-rater agreement was observed for the depth of involvement (ICC=0.71), with highest reliability for intermuscular fascia (Kappa=0.79).

Conclusions:

• An efficient MRI protocol can categorize morphea variations across tissue compartments.
• The study achieved good-to-fair inter-rater reliability, supporting MRI's utility in diagnosing morphea.
• Approximately one-third of patients exhibited deep tissue involvement, highlighting the importance of comprehensive MRI evaluation.