Low-cost, low-field dedicated extremity magnetic resonance imaging in early rheumatoid arthritis: a 1-year follow-up study.
OBJECTIVE
To study the ability of low-cost low-field dedicated extremity magnetic resonance imaging (E-MRI) to assess and predict erosive joint damage in the wrist and metacarpophalangeal (MCP) joints of patients with early rheumatoid arthritis.


METHODS
24 previously untreated patients with rheumatoid arthritis with joint symptoms for <1 year were evaluated at the time of diagnosis and after 6 and 12 months of methotrexate treatment with conventional clinical or biochemical examinations, x rays of both hands and wrists, and E-MRI of the dominant wrist and MCP joints.


RESULTS
At baseline, all patients showed magnetic resonance imaging (MRI) synovitis, and MRI erosions were detected in 21 bones (10 patients). 6 (29%) of these, distributed among two patients, were seen on x ray. One x ray erosion was not detected by MRI. At 1 year, MRI and x ray detected 15 and 8 new erosions, respectively, and 19% of MRI erosions at baseline had progressed to x ray erosions. In bones with MRI erosions at baseline, the relative risk of having x ray erosions at the 1-year follow-up was 12.1, compared with bones without baseline MRI erosions (lesion-centred analysis). If bones with baseline x ray erosions were excluded, the relative risk was 5.2. In patients with baseline MRI bone erosion or oedema, the relative risk of having x ray erosions at 1 year was 4.0, compared with patients without these signs at baseline (patient-centred analysis).


CONCLUSIONS
In this group of patients with early rheumatoid arthritis who were treated uniformly, baseline E-MRI erosions in MCP or wrist bones markedly increased the risk of x ray erosions at the 1-year follow-up. Low-cost, low-field dedicated extremity MRI is promising for assessment and prognostication of early rheumatoid arthritis.
Department of Internal Medicine C, Section of Rheumatology, Odense University Hospital, Søndre Boulevard 29, Dk-5000 Odense C, Denmark. lindegaard@dadlnet.dk
H M
HM
Lindegaard
J
J
Vallø
K
K
Hørslev-Petersen
P
P
Junker
M
M
Østergaard
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000000981:diagnostic imaging; D001847:Bone Diseases / Q000175:diagnosis; D018450:Disease Progression; D004487:Edema / Q000175:diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008662:Metacarpophalangeal Joint / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D010147:Pain Measurement; D011379:Prognosis; D011859:Radiography; D012720:Severity of Illness Index; D013585:Synovitis / Q000175:diagnosis; D013717:Tenosynovitis / Q000175:diagnosis; D014955:Wrist Joint / Q000000981:diagnostic imaging / Q000473:pathology