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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
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Do dermatomyositis and polymyositis affect similar thigh muscles? A comparative MRI-based study
Nicolo Pipitone1, Antonella Notarnicola2, Gabriele Levrini3
1Department of Rheumatology, Department of Internal Medicine, Azienda Ospedaliera ASMN, IRCSS, Reggio Emilia, Italy. pipitone.nicolo@asmn.re.it.
Clinical and Experimental Rheumatology
|December 20, 2016
Summary
Dermatomyositis (DM) preferentially affects more thigh muscles than polymyositis (PM), particularly in the anterior compartment. Posterior thigh muscles show similar involvement in both inflammatory myopathies.
Area of Science:
- Rheumatology
- Neurology
- Radiology
Background:
- Dermatomyositis (DM) and polymyositis (PM) are inflammatory myopathies causing muscle weakness.
- Thigh muscle involvement in DM and PM is common but debated.
- Muscle edema on MRI indicates active inflammation.
Purpose of the Study:
- To compare thigh muscle inflammation patterns in DM and PM using MRI.
- To identify specific thigh muscle groups preferentially affected in DM versus PM.
Main Methods:
- Analyzed MRI scans of 31 DM and 40 PM patients.
- Assessed edema in 17 pelvic floor and thigh muscles using fat-suppressed sequences.
- Calculated MRI edema scores and compared muscle group involvement between DM and PM.
Main Results:
- DM patients had shorter disease duration than PM patients.
- Muscle edema was more frequent in DM than PM, except in posterior thigh muscles.
- Anterior thigh muscle involvement was significantly higher in DM (68%) compared to PM (38%).
Conclusions:
- DM affects a broader range of thigh muscles than PM.
- Posterior thigh compartment muscles are similarly affected in both DM and PM.
- Findings can guide targeted physiotherapy for inflammatory myopathies.
