Rheumatoid nodules: MR/pathological correlation.

PURPOSE: To demonstrate the signal characteristics of subcutaneous rheumatoid nodules in correlation to their histopathologic features.

METHOD: The magnetic resonance imaging (MRI) features of biopsy proven subcutaneous rheumatoid nodules are described in five patients with rheumatoid arthritis established by classic criteria.

RESULTS

Two morphologic appearances of rheumatoid nodules were observed on MRI: one predominantly cystic, with enhancing peripheral component; and a second type which is predominantly solid, with uniform enhancement following gadolinium injection.

CONCLUSION

Subcutaneous rheumatoid nodules can appear by MR as solid, cystic, or a combination of both components. This closely correlates with their histopathologic evolution.