Magnetic Resonance Imaging (MRI)
- Magnetic Resonance Imaging (MRI) is very sensitive to early changes in JIA and can differentiate between bony and soft tissue lesions.
- However, MRI is not always available, is expensive and requires sedation or general anaesthesia in younger children.
- Intravenous contrast, such as gadolinium, is often used and is important in the assessment of synovitis.
- In the context of inflammatory back pain, MRI of the spine and sacroiliac joints (with gadolinium) is warranted given that radiographs are very difficult to interpret in adolescents and radiation exposure is a factor.
The MRI of the ankle below, shows extensive synovitis with effusion in the ankle and mid-foot (box) in JIA. The MRI was performed with gadolinium showing enhancement changes (arrows) consistent with inflammation.