The Prevalence of MRI-Defined Sacroiliitis and Classification of Spondyloarthritis in Patients with Acute Anterior Uveitis: A Longitudinal Single-Centre Cohort Study

Background: Acute anterior uveitis (AAU) is a relatively common extra-musculoskeletal manifestation of axial spondyloarthritis (axSpA); however, data on the prevalence of active sacroiliitis in patients with AAU are limited. Methods: 102 patients with AAU and 39 healthy subjects (HS) underwent clinical assessment and sacroiliac joint MRI. Patients with absence of active sacroiliitis were reassessed after two years. International Spondyloarthritis Society (ASAS) classification criteria for axSpA (regardless of patient’s age) and expert opinion for definitive diagnosis of axSpA were applied. Results: Although chronic back pain was equally present in both groups, bone marrow edema (BME) in SIJ and BME highly suggestive of axSpA was found in 52 (51%) and in 33 (32%) patients with AAU compared with 11 (28%) and none in HS, respectively. Out of all AAU patients, 41 (40%) patients fulfilled the ASAS classification criteria for axSpA, and 29 (28%) patients were considered highly suggestive of axSpA based on clinical features. Two out of the 55 sacroiliitis-negative patients developed active sacroiliitis at the two-year follow-up. Conclusions: One-third of patients with AAU had active inflammation on SIJ MRI and clinical diagnosis of axSpA. Therefore, patients with AAU, especially those with chronic back pain, should be referred to a rheumatologist, and the examination should be repeated if a new feature of SpA appears.

Method for Diagnosing the Bone Marrow Edema of Sacroiliac Joint in Patients with Axial Spondyloarthritis Using Magnetic Resonance Image Analysis Based on Deep Learning

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease of the sacroiliac joints. In this study, we develop a method for detecting bone marrow edema by magnetic resonance (MR) imaging of the sacroiliac joints and a deep-learning network. A total of 815 MR images of the sacroiliac joints were obtained from 60 patients diagnosed with axSpA and 19 healthy subjects. Gadolinium-enhanced fat-suppressed T1-weighted oblique coronal images were used for deep learning. Active sacroiliitis was defined as bone marrow edema, and the following processes were performed: setting the region of interest (ROI) and normalizing it to a size suitable for input to a deep-learning network, determining bone marrow edema using a convolutional-neural-network-based deep-learning network for individual MR images, and determining sacroiliac arthritis in subject examinations based on the classification results of individual MR images. About 70% of the patients and normal subjects were randomly selected for the training dataset, and the remaining 30% formed the test dataset. This process was repeated five times to calculate the average classification rate of the five-fold sets. The gradient-weighted class activation mapping method was used to validate the classification results. In the performance analysis of the ResNet18-based classification network for individual MR images, use of the ROI showed excellent detection performance of bone marrow edema with 93.55 ± 2.19% accuracy, 92.87 ± 1.27% recall, and 94.69 ± 3.03% precision. The overall performance was additionally improved using a median filter to reflect the context information. Finally, active sacroiliitis was diagnosed in individual subjects with 96.06 ± 2.83% accuracy, 100% recall, and 94.84 ± 3.73% precision. This is a pilot study to diagnose bone marrow edema by deep learning based on MR images, and the results suggest that MR analysis using deep learning can be a useful complementary means for clinicians to diagnose bone marrow edema.

MRI Detection of Active Sacroiliitis in First Degree Relatives of Ankylosing Spondylitis Patients with Clinical and Laboratory Correlations

Background. Detection of ankylosing spondylitis (AS) in the preclinical stage could help prevent long term morbidity in this patients’ population. The aim of this study was to examine the prevalence of active sacroiliitis in first-degree relatives of AS patients using MRI with clinical and laboratory correlations as these patients may benefit from MRI screening and early treatment.Methods. Seventeen first-degree relatives of AS patients were recruited prospectively. AS screening questionnaires (Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Disease Activity Index & Visual Analogue Scale), blood tests (C-Reactive Protein, HLA-B27), and an MRI of the SIJs were taken. Two musculoskeletal radiologists interpreted the MRI scans, and two physiotherapists applied four symptom provocation tests (Gaenslen's test, posterior pelvic pain provocation test, Patrick's Faber (PF) test and palpation of the long dorsal SIJ ligament test), and two functional movement tests (active straight leg raise and Stork test). Results. Seven (41%) of the 17 participants demonstrated MRI evidence of active sacroiliitis. Of the 7 participants with active sacroiliitis, two (29%) had no history of recent low back pain (LBP), two (29%) had negative HLA-B27, and one (14%) participant had neither back pain nor positive HLA-B27. The Cohen's Kappa score for the interobserver agreement between the radiologists was 1.00 (p-value <0.0001). Despite fair to strong between therapist agreement for the physical test outcomes (Kappa 0.26 to 1.00), the physical test results per se did not have any predictive association with a positive MRI.Conclusions. MRI detected active sacroiliitis in 41% of first-degree relatives of AS patients. The lack of a history of prior LBP or positive HLA-B27 in active sacroiliitis participants might suggest that MRI screening for this high-risk population is warranted; however, further larger studies are needed to help elucidate its cost-effectiveness and long-term benefits.

OP0257 VALUE OF COLOR DOPPLER ULTRASOUND ASSESSMENT OF SACROILIAC JOINTS IN NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS:A COMPARISON WITH ANKYLOSING SPONDYLITIS

Background:Ultrasound (US) is an accessible imaging technique with a possible role to diagnose active sacroiliitis, so this technique is projected as a promising diagnostic tool for the diagnosis of spondyloarthritis(SpA).The diagnostic value of sacroiliac US has been studied in patients with Ankylosing Spondylitis(AS),becoming a useful and practical tool in comparison with MRI.There are scarce data on the utility of US in the evaluation of Non-radiographic Axial Spondyloarthritis (nr-axSpA).Objectives:The aim of this study is to evaluate the diagnostic utility of color Doppler ultrasound (CDUS) for the detection of sacroiliitis in patients with nr-axSpA and AS.Methods:Patients with nr-axSpA (n=114) and AS(n=80) were enrolled in the study with standardized clinical criteria.According to the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI),nr-axSpA and AS patients were separately divided into active group(n=47,n=43)and inactive group (n=67,n=37).All patients underwent clinical evaluation,and CDUS of sacroiliac joints (SIJs) within the same week. Vascularization, the resistive index (RI) of the SIJs and the first foraminal ramus of the lateral sacral artery were observed and measured by a sonographer who is blinded to initial clinical and radiological assessments. The associated statistics and graphs was utilized to obtain the relationship,which were reflected by the Co-index receiver operating characteristic(ROC)curve or calculating the area under ROC curve(AUC),between the RI of the SIJs and the RI of the first foraminal ramus of the lateral sacral artery in nr-axSpA and AS by using the Logistic Regressive analysis methods,SPSS24.0 and MedCalc19.6.0 software.With MRI-proven sacroiliitis as thediagnostic standard,the Kappa test were used to measure the consistency between the RI of the SIJs and MRI.Results:1. The RI of the SIJs(AUC=0.855,P<0.001)and Co-index(AUC=0.886,P<0.001)were similar sufficient (Z=1.331, P=0.183) to distinguish the active and inactive group in nr-axSpA .2.The RI of the SIJs(AUC=0.869,P<0.001)and Co-index(AUC=0.893,P<0.001)were also similar sufficient (Z=1.292, P=0.196) to distinguish the active and inactive group in AS .3.Neither of the RI of the first foraminal ramus of the lateral sacral artery in nr-axSpA(AUC=0.748,P<0.001)and AS(AUC=0.674,P=0.003)was outstanding to distinguish the active and inactive group.4.The RI of the SIJs was similar sufficient (Z=0.267,P=0.790) to detect sacroiliitis in nr-axSpA and AS.5. The Co-index was also similar sufficient (Z=0.146, P=0.884) to detect sacroiliitis in nr-axSpA and AS.6.The RI of the SIJs in nr-axSpA and AS showed moderate consistency with MRI(the Kappa values were 0.534 and 0.609,respectively,P<0.01).Conclusion:The RI of the SIJs is a possible role to diagnose active sacroiliitis, so CDUS is projected as a promising diagnostic tool for the diagnosis of nr-axSpA and AS in comparison with MRI.References:[1]Rosa JE, Ruta S, Bravo M, et al. Value of Color Doppler Ultrasound Assessment of Sacroiliac Joints in Patients with Inflammatory Low Back Pain. J Rheumatol. 2019 Jul;46(7):694-700.Disclosure of Interests:None declared

POS0939 WHEN DO THE ACTIVE SACROILIITIS MRI FINDINGS LOSS IN ANKYLOSING SPONDYLITIS? A RETROSPECTIVE, CROSS-SECTIONAL, OBSERVATIONAL STUDY

Background:Ankylosing Spondylitis (AS) is an inflammatory rheumatic disease that affects the spine and sacroiliac joints (SIJ). Non-steroidal anti-inflammatory drugs (NSAIDs), modifying antirheumatic drugs (DMARDs), and recently anti-TNF blockers, which are more costly than NSAIDs but used in resistant cases, are generally used in its treatment (1).Objectives:While SIJ-MRI is one of the imaging methods in the diagnosis of the disease, it is not yet used in its follow-up (2). We wanted to define when the activated SIJ-MRI findings, which showed early sacroiliitis, regressed according to the treatment option.Methods:Among the 8100 SIJ-MRIs taken in our hospital in the last 5 years, those that were reported normally were excluded from the study. Among the remaining 1150 patients with active or chronic SIJ findings, a total of 87 patients who were diagnosed with AS and had active SIJ findings in the first imaging and had a second SIJ-MRI examination for any reason were included in our retrospective, cross-sectional and observational study. According to the treatment option, how long the active SIJ-MRI findings disappeared was calculated in months using the Kaplan-Meier method.Results:Of the 87 patients examined in the study, 41 were women and 46 were men. The average age is 32.7. Active SIJ-MRI findings disappeared in a mean of 30.6 months for 11 of 24 patients who did not use any medication, in a mean of 33.9 months for 6 of 16 patients using NSAIDs, in a mean of 40.7 months for 14 of 34 patients using sulfasalazine, in a mean of 28.2 months for 3 of 6 patients using adalimumab, in a mean of 24.4 months for 3 of 5 patients using methotrexate, 11.9 month for 2 of 1 patient using certolizumab. There was no statistically significant difference between the groups.Conclusion:The signs of active sacroiliitis disappeared in less time in patients who did not receive any treatment than those using NSAIDs and sulfasalazine. Patients using anti-TNF blockers had earlier results than those using no medication. The reason for this may be the progressive course of patients who are switched to the next level of treatment and their late response to treatment, as well as the mechanism of the disease (2-3). This situation brings to the agenda the tendency of physicians to over-treat the disease. More randomized controlled studies are needed regarding new treatment options.References:[1]Braun J. ‘Axial spondyloarthritis including ankylosing spondylitis’ Rheumatology (Oxford). 2018 1;57(suppl_6):vi1-vi3.[2]Braun J, Baraliakos X, Golder W, Brandt J, Rudwaleit M, Listing J, Bollow M, Sieper J, van der Heijde D. Magnetic resonance imaging examinations of the spine in patients with ankylosing spondylitis, before and after successful therapy with infliximab. Arthritis & Rheumatism Vol. 48, No. 4, April 2003, pp 1126–1136.[3]Jee WH, McCauley TR, Lee SH, Kima SH, Ima SA, Had KY. Sacroiliitis in patients with ankylosing spondylitis: association of MR findings with disease activity. Magnetic resonance imaging 2004:22;245–250.Disclosure of Interests:None declared

POS0938 A NEW APPROACH FOR ULTRASOUND GUIDED SACROILIAC JOINT INJECTIONS IN SPONDYLOARTHRITIS

Background:Sacroiliac joints (SIJ) inflammation and pain is particularly common in patients with Spondyloarthritis (SpA). SIJs injections represent a valuable therapeutic option in this condition. Traditionally this procedure (irrespective of the guidance method) aims at the lower (synovial) part of the joint. However, there is growing body of evidence that enthesitis rather than synovitis is the cardinal pathological lesion in SpA. Thus, an approach targeting the more superior (ligamentous) part of the joint, with the numerous entheses of the intraspinous sacroiliac ligaments placed there, could be more beneficial in SpA patients with active sacroiliitis. The Posterior sacroiliac ligament (PSIL) is the most superficial of the SIJ ligaments, covering the other dorsally. Thus, using PSIL as a landmark and placing the needle tip beneath it, the injected solution will inevitably spread in the ligamentous portion of the joint.Objectives:To assess the feasibility and efficacy of a new technical approach of ultrasound (US) guided SIJ injections in SpA targeting the ligamentous part of the joint.Methods:The feasibility and efficacy of our approach was tested on 22 consecutive SpA patients, after an inform consent, with pain in the SIJ that did not respond to NSAIDS and who were otherwise on a stable medical treatment. A solution consisting of 7 mg Betamethasone (1ml) and 1% Lidocaine (1.5 ml) was administered to all injected SIJs. The efficacy of the procedure was assessed by patients reported outcome measures: mean reported pain level (on VAS), level of disability due to the back pain (Roland Morris Disability Questionnaire – RMDQ) and quality of the night sleep (Jenkins Sleep Evaluation Questionnaire – JSEQ). They were filled by the patients at baseline and two months after the intervention.Methodology of the procedure: All injections were done with patients in a prone position using an Esaote My Lab 7 machine and a linear transducer (3-12 MHz). After visualization of the SIJ cleft, the probe was slide caudally to the level of the second sacral foramen. Then the probe was rotated to a slightly oblique position with its lateral part higher and the medial part lower. In this way the probe became parallel to the PSIL, and latter is visualized sufficiently well in its long axis. Then, in this position, a 22G, 9 mm spinal needle (Spinocan) was inserted at the medial side of the probe following an in-plane free-hand technique and advanced in cranio-lateral direction. When the needle tip was seen to penetrate the PSIL, and thus enter the SIJ ligamentous part, 0.2 ml of the solution was injected to confirm that it spreads beneath the PSIL, rather than above or in this ligament. After that, a Color Doppler (CD) box was activated and placed over the SIJ to monitor the spread of the injected solution and ensure that it keeps bellow the PSIL. The whole solution was injected under this direct US and CD visualization and the needle tip was repositioned again beneath the PSIL if needed during the procedure.Feasibility of this injection approach was assessed on the basis of the encountered difficulties in adequate visualization of the PSIL and the injected solution flow beneath it from the start until the end of the intervention.Results:The results of the procedure, assessed in two months showed that the mean pain score decreased by 68% (VAS from7.22±1.23 to 2.28±2.37), the disability score - by 46% (RMDQ from 11.86±5.12 to 6.42±6.39), and the sleep quality improved by 41% (JSEQ from 9.86±4.76 to 5.84±3.43). The procedure was found completely feasible by the performing operator and the visualization of the landmark (PSIL) was adequate in all patients and throughout the whole procedure. The CD allowed to confirm reliably that the solution is injected under the PSIL at any time point.Conclusion:The SIJ injections performed by our approach and targeting the ligamentous part of the joint, proved to be completely feasible and furthermore – efficient, in alleviating the symptoms of active sacroiliitis in SpA patients.Disclosure of Interests:None declared

OP0142 NETAKIMAB REDUCES ANKYLOSING SPONDYLITIS ACTIVITY IN PATIENTS WITH OR WITHOUT SACROILIITS ON MRI: RESULTS OF SUBANALYSIS OF PHASE 3 ASTERA TRIAL

Background:The presence of sacroiliitis in patients (pts) with ankylosing spondylitis (AS) on imaging can be established both by sacroiliac joint (SIJ) X-ray or MRI. Active sacroiliitis on MRI as defined by ASAS is predictor of good treatment response to biological disease modifying anti-rheumatic drugs [1, 2]. Netakimab (NTK) is a humanized anti-interleukin-17A antibody approved for the treatment of AS, psoriatic arthritis, moderate-to-severe plaque psoriasis in Russia and Belarus. The difference in treatment response to NTK in AS pts with and without active sacroiliitis on MRI (MRI+/MRI−) is unclear.Objectives:To report the changes in AS activity in pts with and without sacroiliitis on MRI at week 16 of NTK treatment.Methods:ASTERA (NCT03447704) is an ongoing phase 3 placebo (PBO)-controlled clinical study, aimed at evaluating NTK efficacy in AS. All pts fulfilled modified New York criteria. Evaluation of acute inflammation on SIJ MRI was performed at the baseline but was not an inclusion criterion. This analysis includes pts received subcutaneous NTK 120 mg every 2 wks with available baseline SIJ MRI. The presence of sacroiliitis on MRI was defined as SPARCC>2. Efficacy endpoints included ASAS20/40, ASAS partial remission (PR), changes from baseline in BASDAI (Bath Ankylosing Spondylitis Disease Activity Index), ASDAS-CRP (Ankylosing Spondylitis Disease Activity Score).Results:67 MRI+ and 46 MRI− pts were included into analysis. Baseline characteristics were balanced across both arms. 42.4% of MRI+ pts and 38.3% of MRI− pts achieved ASAS40 at week 16 (p≥0.05), ASAS20 was observed in 65.2%/55.3% pts in the same arms respectively (p≥0.05). ASAS PR was reported for 15.2% MRI+ and 17.0% MRI− pts (p≥0.05). Improvements in BASDAI and ASDAS-CRP were similar across both arms. At wk 16, mean change from baseline in BASDAI was −2.7 vs −3.0 for MRI+ and MRI− pts respectively, mean change in ASDAS-CRP was −1.7 vs −1.4 in the same arms (p≥0.05 for all), (figure 1).Figure 1.Clinical improvements in AS disease activity. Mean change from baseline is shown for (A) ASDAS-CRP, and (B) BASDAIConclusion:NTK leads to decline of disease activity in AS pts irrespectively of sacroiliitis on MRI.References:[1]Rudwaleit M, et al. MRI in predicting a major clinical response to anti-tumour necrosis factor treatment in ankylosing spondylitis. Ann Rheum Dis. 2008;67(9):1276-81.[2]Sieper J, et al. A randomized, double-blind, placebo-controlled, sixteen-week study of subcutaneous golimumab in patients with active nonradiographic axial spondyloarthritis. Arthritis Rheumatol. 2015;67(10):2702-12.Acknowledgements:This study was sponsored by JSC BIOCAD.Disclosure of Interests:Inna Gaydukova Speakers bureau: Abbvie, Biocad, Eli Lilly, MSD, Novartis, Pfizer, Sandoz, V Mazurov: None declared, Shandor Erdes: None declared, Tatiana Dubinina: None declared, Alena Kundzer: None declared, Nikolaj Soroka: None declared, Anna Eremeeva Employee of: Biocad