Rheumatology Practice Test

Inflammatory myopathies produce active inflammation that shows up as edema in affected muscles. MRI is the most sensitive way to visualize this edema across multiple muscles because it provides excellent soft tissue contrast. Using fat-suppressed T2-weighted or STIR sequences, inflamed muscles appear bright, revealing the areas of active disease. This mapping lets you target the biopsy to the most inflamed region, improving the chance of a diagnostic specimen and reducing sampling of non-involved tissue. Contrast-enhanced imaging with gadolinium can further highlight inflamed areas by showing increased vascular permeability and enhancement. Other imaging options don’t locate active inflammation as reliably. X-rays don’t show soft tissue changes relevant to inflammatory myopathy. CT has limited soft tissue contrast for muscle and involves radiation. Ultrasound can detect some edema but is operator-dependent and less comprehensive for deep or multiple muscles. MRI’s sensitivity and scope make it the best choice for guiding biopsy in suspected inflammatory myopathies.