ABSTRACT
Magnetic resonance imaging (MRI) is the modality of choice in early diagnosis and
management of rheumatoid arthritis (RA). The pathologic processes in RA involve synovitis,
joint effusion, proliferation of fibrovascular connective tissue, and the formation
of pannus. Other imaging techniques available for imaging of RA include ultrasound,
scintigraphy, computed tomography, and plain radiography (PR). MRI provides high sensitivity
in detecting inflammatory changes in the joints. Several studies report high intra-
and interobserver reliability and low variation for MRI. MRI allows detection and,
in some cases, quantification of synovial changes. Dynamic MRI is a new technique
that utilizes rate of synovial enhancement in evaluation of inflammatory changes.
MRI allows visualization of erosions in three orthogonal planes. MRI has been shown
in many studies to have much greater sensitivity than PR in detecting erosions. Use
of a contrast agent further increases the sensitivity in detecting erosions and differentiates
and outlines synovial proliferation from fluid collection. Other manifestations of
RA such as intraosseous cysts, tenosynovitis, bone marrow edema, and carpal tunnel
syndrome can also be visualized on magnetic resonance images. Advances in MRI include
contrast-enhancement, dynamic, and quantitative techniques. MRI assists in the early
detection of RA, which allows earlier initiation of treatment with disease-modifying
therapies.
KEYWORDS
Magnetic resonance imaging - rheumatoid arthritis - imaging techniques
