THU0579 Validation of contrast-enhanced mri scores on (TENO)synovitis of the wrist in juvenile idiopathic arthritispatients by comparison with children unaffected by clinical arthritis
Authors: J.M. Van Der Krogt, E.C. van Gulik, R. Hemke, J.M. van den Berg, D. Schonenberg, A. Kindermann, K.M. Dolman, M.A. Benninga, T.W. Kuijpers, M. Maas, C.M. Nusman
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Delayed and/or inappropriate treatment of juvenile idiopathic arthritis (JIA) may lead to permanent loss of joint functionality.<sup>1</sup> Contrast-enhanced MRI is increasingly being accepted as a sensitive tool for detecting JIA disease activity in an early stage.<sup>2</sup> <h3>Objectives</h3> The aim of this study was to assess the validity of two reliable contrast-enhanced MRI scores for the assessment of synovitis and tenosynovitis in the wrist of clinically active JIA patients by a comparison with children unaffected by clinical arthritis. <h3>Methods</h3> An axial T1-weighted MRI sequence with contrast-enhancement and fat-saturation was performed on the wrist of 25 children who had no signs of joint inflammation at clinical examination and who were already subjected to contrast-enhanced MR enterography. Wrist MRI scans of 25 clinically active JIA patients were matched based on time-interval between contrast injection and start of the MRI sequence. After being blinded for clinical status, two radiologists scored synovitis and tenosynovitis in consensus. Synovitis was scored at 5 locations by degrees of synovial enhancement (0–2 scale) and synovial inflammation (0–3 scale). Tenosynovitis was scored at the extensor tendons (compartments II, IV and VI) and flexor tendons by degree of inflammation based on a 0–3 scale.<sup>3, 4</sup> <h3>Results</h3> Children unaffected by clinical arthritis had significantly lower total synovial enhancement (median=1 vs 4, p&lt;0.001) and total synovial inflammation (median=1 vs 4, p&lt;0.001) scores compared to clinically active JIA patients (graph). No significant difference in total tenosynovitis score was found between both groups (median=0 vs 0, p<i>=</i>0.220). Fifteen out of 25 (60%) clinically active JIA patients were given a total tenosynovitis score of 0. <h3>Conclusions</h3> The contrast-enhanced MRI scores for the assessment of synovial enhancement and synovial inflammation in the wrist of clinically active JIA patients appear valid. Due to a low incidence of wrist tenosynovitis in this cohort, the validity of the tenosynovitis score could not be assessed. These findings further establish contrast-enhanced MRI as a diagnostic tool with synovitis as the primary target of disease in the wrist of JIA patients. <h3>References</h3> [1] Hoeksma AF, et al. High prevalence of hand- and wrist-related symptoms, impairments, activity limitations and participation restrictions in children with juvenile idiopathic arthritis. J Rehabil Med2014. [2] Colebatch-Bourn AN, et al. EULAR-PReS points to consider for the use of imaging in the diagnosis and management of juvenile idiopathic arthritis in clinical practice. Ann Rheum Dis2015. [3] Damasio MB, et al. MRI of the wrist in juvenile idiopathic arthritis: proposal of a paediatric synovitis score by a consensus of an international working group. Results of a multicentre reliability study. Pediatr Radiol2012. [4] Lambot K, et al. MRI assessment of tenosynovitis in children with juvenile idiopathic arthritis: inter- and intra-observer variability. Pediatr Radiol2013. <h3>Disclosure of Interest</h3> None declared