This study proposes the use of a PET isotope, [18F]-Fibroblast Activation Protein Inhibitor-74, for a prospective single-center, single-arm study using MRI imaging for participants with Refractory Dermatomyostitis.

Inclusion Criteria:

1. Patients with suspected dermatomyositis.
2. Patient must be > 18 years old.
3. Be willing and able to provide written informed consent for the trial.

Exclusion Criteria:

1. Women who are pregnant or potentially pregnant per the Department of Radiology Policy on Imaging in Potentially Pregnant and Pregnant Women.
2. Contraindication to MRI or inability to lie flat for 30 min
3. Any serious medical condition that in the opinion of principal investigator could pose significant risk of harm or injury to the patient if they participate in the study

No plans to share.