OP0252 ARTHRITIS AND ENTHESITIS IN THE HIP AND PELVIS REGION IN SPONDYLOARTHRITIS – VALIDATION OF TWO WHOLE-BODY MRI METHODS

Abstract

Background:Whole-body MRI (WB-MRI) allows assessment of the overall inflammation in arthritis patients, including joint and entheses. To enhance the use of WB-MRI in clinical trials, the OMERACT MRI in Arthritis Working Group developed the OMERACT MRI Whole-body score for Inflammation in Peripheral joints and Entheses in inflammatory arthritis (MRI-WIPE) [1]. This has been validated for the entire body, including the hip/pelvis region, but not for each individual region. More detailed scoring systems exist for heels, hands and feet but although hip arthritis is a key cause of functional impairment in spondyloarthritis (SpA), no detailed scoring system has been published for use in SpA. The Hip Inflammation Magnetic Resonance Imaging Scoring System (HIMRISS) was developed and validated in osteoarthritis showing good reliability.Objectives:To validate reliability, correlation and responsiveness of two WB-MRI scores for the hip/pelvis region in SpA.Methods:Inflammation in the hip/pelvis region was assessed on coronal WB-MRIs in 4 iterative multi-reader exercises using MRI-WIPE for the hip/pelvis region and HIMRISS (Figure 1). In final exercises, images (axial/peripheral SpA and psoriatic arthritis) were obtained before and after TNF-inhibitor.Results:In final exercises reliability was mostly good for the best calibrated readers. Median single-measure intraclass correlation coefficients were 0.58-0.65 (WIPE osteitis), 0.10-0.88 (HIMRISS osteitis), 0.38-0.72/0.52-0.60 (WIPE synovitis/effusion) and 0.68-0.89/0.78-0.85 (HIMRISS synovitis/effusion) (Table 1). The methods correlated significantly for status in osteitis (0.72, p=0.019) and for synovitis/effusion status (0.83, p=0.003) and change (0.73, p=0.017) (Table 1). In exercise 4 Wilcoxon signed-rank test showed significant change in osteitis between timepoints using WIPE hip/pelvis and SRM was large (1.23), while lower for WIPE synovitis/effusion and HIMRISS.Table 1.MRI-WIPE hip/pelvis and HIMRISS interreader reliability for OMERACT exercises 3-4MRI-WIPE hip/pelvisHIMRISSOsteitisSynovitis/effusionOsteitisSynovitis/effusionVariablesNo. patients(cases)Type of scoreMeanscoreICCMeanscoreICCMeanscoreICCMeanscoreICCExercise 39 readers11Status2.3 (0-10)0.69 (0.23-0.93)1.4 (0-4)0.58 (-0.06-0.96)8.2 (1-60)0.84 (0.56-0.99)12.8 (3-25)0.52 (0.00-.91)11Change-0.2 (-1-1)NA-0.2 (-3-1)0.50 (0.10-0.87)-0.35 (-3-1)NA-1.8 (-17-10)0.50 (-0.05-0.89)Exercise 33 readers11Status1.8 (0-10)0.63 (0.46-0.93)1.7 (0-5)0.60 (0.34-0.80)6.6 (0-65)0.88 (0.77-0.94)12.8 (2-28)0.89 (0.87-0.91)11Change-0.12 (-1-1)NA-0.12 (-3-2)0.60 (0.48-0.83)-0.7 (-7-0)NA-1.6 (-21-8)0.78 (0.70-0.87)Exercise 49 readers10 (1-10)Status1.2 (0-4)0.21 (-0.39-0.91)1.1 (0-2)0.19 (-0.31-0.69)1.8 (0-6)0.07 (-0.17-0.83)16.4 (9-23)0.31 (0.00-0.89)10 (11-20)Status1.6 (0-6)0.51 (-0.08-0.99)1 (0-3)0.40 (-0.17-0.88)3.5 (1-8)0,08 (-0.21-0.95)11.2 (5-24)0.49 (0.00-0.94)10 11-20)Change-0.4 (-2-0)NA-0.39 (-2-0)0.22 (-0.68-0.83)-2.2 (-7-2)NA-5.2 (-18-0)0.57 (0.02-0.92)20 (1-20)Status1.4 (0-6)0.41 (-0.35-0.92)1.0 (0-3)0.27 (-0.07-0.75)2.7 (0-9)0.09 (-0.17-0.85)13.8 (5-25)0.45 (0.01-0.90)Exercise 43 readers10 (1-10)Status0.8 (0-4)0.29 (0.01-0.78)1.3 (0-2)-0.02 (-0.29-0.12)0.4 (0-2)-0.04 (-0.04-0.04)15.8 (5-26)0.73 (0.59-0.89)10 (11-20)Status1.8 (0-9)0.65 (0.52-0.76)1.2 (0-4)0.72 (0.62-0.81)1.7 (0-5)0.06 (-0.17-0.35)9.2 (2-26)0.68 (0.53-0.88)10 (11-20)Change-0.6 (-2-0)NA-0.5 (-3-1)0.52 (0.49-0.55)-0.2 (-2-1)NA-2.8 (-19-6)0.85 (0.82-0.88)20 (1-20)Status1.3 (0-9)0.58 (0.43-0.69)1.2 (0-4)0.38 (0.31-0.44)1.0 (0-5)0.10 (-0.09-0.33)12.5 (2-26)0.73 (0.69-0.77)Sum scores and ICCs are mean (range). ICC is 2-way mixed, single measure, by absolute agreement.Conclusion:MRI-WIPE and HIMRISS may be useful tools in modular WB-MRI evaluation of hip/pelvis inflammation in clinical trials in SpA.