Dynamic contrast-enhanced magnetic resonance imaging in the assessment of disease activity in patients with juvenile idiopathic arthritis.
OBJECTIVE
To determine the capability and reliability of dynamic contrast-enhanced MRI (DCE-MRI) in the assessment of disease activity in juvenile idiopathic arthritis (JIA).


METHODS
DCE-MRI of the clinically more affected wrist or hip joints was undertaken in 21 patients, coupled with standard clinical assessment and biochemical analysis. Synovial inflammation was assessed by computing the maximum level of synovial enhancement (ME), the maximum rate of enhancement (MV) and the rate of early enhancement (REE) from the enhancement curves generated from region of interest independently delineated by two readers in the area of the ME. Correlations between dynamic parameters and clinical measures of disease activity, and static MRI synovitis score were investigated.


RESULTS
In patients with wrist arthritis, REE correlated with the wrist swelling score (r(s) = 0.72), ESR (r(s) = 0.69), pain assessment scale (r(s) = 0.63) and childhood HAQ (r(s) = 0.60). In patients with hip arthritis, ME correlated with the hip limitation of motion (r(s) = 0.69). Static MRI synovitis score based on post-gadolinium enhancement correlated with MV (r(s) = 0.63) in patients with wrist arthritis and with ME (r = 0.68) in those with hip arthritis. The inter-reader agreement assessed by intra-class correlation coefficient (ICC) for ME, MV and REE (ICC = 0.98, 0.97 and 0.84, respectively) was excellent.


CONCLUSIONS
DCE-MRI represents a promising method for the assessment of disease activity in JIA, especially in patients with wrist arthritis. As far as we know, this study is the first to demonstrate the feasibility, reliability and construct validity of DCE-MRI in JIA. These results should be confirmed in large-scale longitudinal studies in view of its further application in therapeutic decision making and in clinical trials.
Malattia
Clara
C
Pediatria II, IRCCS G. Gaslini, Largo G. Gaslini 5, 16147 Genova, Italy. claramalattia@ospedale-gaslini.ge.it
Damasio
Maria B
MB
Basso
Curzio
C
Verri
Alessandro
A
Magnaguagno
Francesca
F
Viola
Stefania
S
Gattorno
Marco
M
Ravelli
Angelo
A
Tomà
Paolo
P
Martini
Alberto
A
D001171:Arthritis, Juvenile / Q000175:diagnosis*; D002648:Child; D005260:Female; D006621:Hip Joint / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D015588:Observer Variation; D010147:Pain Measurement / Q000379:methods; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013585:Synovitis / Q000175:diagnosis; D014955:Wrist Joint / Q000473:pathology