SAT0664 Cartilage damage quantitatively assessed by mri using t2 mapping in ccp-positive ra patients
Authors: N. Renner, A. Kleyer, G. Krönke, D. Simon, J. Rech, G. Schett, G. Welsch, M.L. Pachowsky
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> T2 mapping is a non-invasive quantitative MRI approach which reflects cartilage hydration and collagen integrity without using contrast enhancement. It is a sensitive tool to determine cartilage damage and is currently spreading into broader clinical application.<sup>1</sup> <h3>Objectives</h3> This study aimed to analyse biochemical changes in cartilage of Metacarpophalangeal (MCP) joints in patients with rheumatoid arthritis (RA) using T2 mapping in a 3 T MRI setting. <h3>Methods</h3> Thirty RA patients fulfilling the 2010 ACR/EULAR criteria were recruited. Image acquisition was performed using two surface coils in a 3 T MRI whole body scanner (VERIO; SIEMENS Healthcare).<sup>2</sup> We obtained high-resolution images of the 2nd and 3rd MCP joint. T2 maps were calculated using a pixel-wise, mono-exponential, non-negative least-squares-fit analysis. Region-of-interest (ROI) analysis was performed by dividing the cartilage into medial, central and lateral phalangeal (med, cent, lat P) and metacarpal (MC) area. ACPA positive patients were compared to ACPA negative patients. Statistical evaluation was performed by means of univariate ANOVA testing with random factors. A p-value&lt;0.05 was considered statistically significant. The study protocol was approved by the local ethics commission. Written informed consent was obtained from all patients <h3>Results</h3> Fourteen ACPA positive (3 male/11 female) and 16 ACPA negative patients (6 male/10 female) were included. Mean age, sex distribution and disease duration were comparable (age: 49.0±15.1 years (ACPA+) vs. 56.1±10.9 years (ACPA-), t=1.494, p=0.146; sex distribution: χ2 (1)=0.918, p=0.338, disease duration: 7.9±7.3 years (ACPA+) vs. 3.9±3.8 years (ACPA-), U=69.0, Z=−1.799, p=0.072). T2 values were significantly higher in the majority of the ROIs in ACPA-positive (+) RA patients compared to ACPA negative (-) patients with a statistical significance in five of the six ROIs. T2 values in ms: MC med (+) 41.3±15.3 vs. (-) 29.6±7.4 p=<b>0.010,</b> cent (+) 43.8±14.6 vs.(-) 28.4±10.9, p=<b>0.001,</b> lat (+) 45.6±13.8 vs. (-) 32.0±8.6, p=<b>0.008.</b> P: med (+) 30.3±14.6 vs. (-) 25.7±14.0, p=0.169, cent (+) 29.9±13.0 vs. (-) 22.5±10.1, p=<b>0.014, l</b>at (+) 37.0±15.9 vs. (-) 28.8±12.6, p=<b>0.039.</b> <h3>Conclusions</h3> T2 mapping is a clinically feasible non-invasive MR tool for cartilage evaluation of RA patients' MC joints. ACPA positive RA patients showed significantly increased T2 values compared to ACPA negative patients reflecting a more severe cartilage alteration despite comparable disease duration. <h3>References</h3> [1] Welsch GH, Apprich S, Zbyn S, Mamisch TC, Mlynarik V, Scheffler K, Bieri O, Trattnig S: Biochemical (T2, T2* and magnetisation transfer ratio) MRI of knee cartilage: feasibility at ultra-high field (7T) compared with high field (3T) strength. European radiology2011;21(6):1136–1143. [2] Renner N, Kronke G, Rech J, Uder M, Janka R, Lauer L, Paul D, Herz B, Schlechtweg P, Hennig FF, et al. Anti-citrullinated protein antibody positivity correlates with cartilage damage and proteoglycan levels in patients with rheumatoid arthritis in the hand joints. Arthritis &amp; rheumatology (Hoboken, NJ)2014;66(12):3283–3288. <h3>Disclosure of Interest</h3> None declared