Search

Objective: In a number of patients with clinically active juvenile idiopathic arthritis (JIA), contrast-enhanced MRI shows no signs of synovitis. The objective of this study was to assess the frequency and the patient characteristics in clinically active JIA patients in which MRI showed no signs of synovitis., Methods: From our cohort of 313 patients in which contrast-enhanced MRI of the knee had been performed, we selected 72 JIA patients with clinically active disease involving the target joint. The validated Juvenile Arthritis MRI Scoring (JAMRIS) system was used to evaluate synovial thickening. Patients were divided into two groups based on MRI outcome: Group 1: thickened synovium on MRI (JAMRIS score ≥1) or Group 2: normal synovium on MRI (JAMRIS score 0). Patient characteristics and disease activity parameters were then compared., Results: In 35% (25/72) of these patients, MRI results contrasted with the clinical assessment (Group 2). In comparison to Group 1, the patients with discrepant findings were significantly older at the date of examination and JIA had been diagnosed at later age (median age of 13.2 vs. 10.9 and median age 10.0 vs. 8.0 respectively). In Group 2 there were significantly more patients with RF-negative polyarticular disease., Conclusion: Patients with RF-negative polyarticular JIA who had been diagnosed at a later age and were older at the time of MRI were most likely to be considered clinically active while MRI showed no signs of synovitis. These particular JIA patients may benefit from monitoring of disease activity by MRI to prevent overtreatment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: To assess the capability of the pixel-by-pixel DCE-MRI time intensity curve (TIC)-shape analysis method in the evaluation of juvenile idiopathic arthritis (JIA) disease activity by correlating DCE-MRI parameters with semi-quantitative conventional-MRI scores of synovitis., Methods: Clinical, laboratory, and (DCE)-MRI datasets of 85 JIA patients were prospectively obtained. TIC-shapes of each voxel were classified into one of seven predefined color-coded TIC shape categories. Spatial information on the relative amount of TIC-shapes, maximal enhancement (ME), maximal initial slope (MIS), initial area under the curve (iAUC), time-to-peak (TTP), enhancing volume (EV) was calculated of the synovial membrane. The grade of synovitis was scored on conventional MR images by two readers using the validated JAMRIS system. The Bonferroni method was used to correct for multiple testing, therefore, a P value of <0.0056 is considered significant (0.05/9=0.0056)., Results: The semi-quantitative JAMRIS synovitis score correlated substantially with the ME, EV, and iAUC (Rs=0.658, P<0.001; Rs=0.618, P<0.001; Rs=0.639, P<0.001), and moderately with MIS (Rs=0.453, P<0.001). A poor correlation was observed between the relative number of TIC-shapes 2-5 and the JAMRIS synovitis score (Rs=0.209, P=0.054; Rs=0.328, P=0.002; Rs=0.241, P=0.023; Rs=-0.241, P=0.026)., Conclusion: In this explorative study, both TIC shape and semi-quantitative DCE-MRI analysis methods showed moderate to substantial correlations with conventional MRI scores of disease activity, indicating that this methods are feasible. Further research is warranted whether DCE-MRI holds potential to become an objective and quantitative method for the evaluation of disease activity in JIA., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: The study was performed to determine whether conventional and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters of a previously affected target joint in patients with clinically inactive juvenile idiopathic arthritis (JIA) have prognostic meaning for a flare of joint inflammation during follow-up., Material and Methods: Thirty-two JIA patients with clinically inactive disease at the time of MRI of the knee were prospectively included. DCE-MRI provided both descriptive measures and time-intensity-curve shapes, representing functional properties of the synovium. Conventional MRI outcome measures included validated scores for synovial hypertrophy, bone marrow edema, cartilage lesions and bone erosions. During a 2-year period the patients were monitored by their pediatric rheumatologist and clinical flares were registered., Results: MRI analysis revealed synovial hypertrophy in 13 (39.4%) of the clinically inactive patients. Twelve patients (37.5%) had at least one flare during 2-year clinical follow-up. Persistently inactive and flaring patients differed significantly in the maximum enhancement of the synovium on the DCE-MRI (p<0.05), whereas no difference was found between these two groups in any of the baseline scores of conventional MRI., Conclusions: Our prospective clinical follow-up study indicates that the assessment of 'maximum enhancement' upon DCE-MRI may be able to predict a clinical flare within 2 years in inactive JIA patients., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)