Reliability of the OMERACT Giant cell arteritis Ultrasonography Score (OGUS): results of a patient-based exercise involving experts and non-experts in vascular ultrasonography

Background:In giant cell arteritis (GCA), various ultrasound composite scores, including the provisional OMERACT GCA ultrasonography score (OGUS), the Southend Halo score and the Halo count, have recently been introduced as...

POS0812 SUBCLAVIAN ARTERIES INVOLVEMENT IN PATIENTS WITH GIANT CELL ARTERITIS: DO WE NEED A MODIFIED HALO SCORE?

The Forensic Reference Phantom—a new tool for quality assurance of attenuation measurements in forensic radiology

ObjectivesTo develop a scoring method to visually score cortical interruptions in finger joints on High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT), determine its intra- and inter-reader reliability and test its feasibility.MethodsThe scoring method was developed by integrating results from in-depth discussions with experts, consensus meetings, multiple reading experiments and the literature. Cortical interruptions were scored by two independent readers in an imaging dataset with finger joints from patients with rheumatoid arthritis (RA) and healthy controls and assessed for adjacent trabecular distortion. Reliability for the total number of cortical interruptions per joint and per quadrant was calculated using intraclass correlation coefficient (ICC). Feasibility was tested by recording the time to analyze one joint.ResultsIn 98 joints we identified 252 cortical interruptions, 17% had trabecular distortion. Mean diameter of the interruptions was significantly larger in patients with RA compared with healthy controls (0.88 vs 0.47 mm, p = 0.03). Intra-reader reliability was ICC 0.88 (95% CI 0.83;0.92) per joint and ICC 0.69 (95% CI 0.65;0.73) per quadrant. Inter-reader reliability was ICC 0.48 (95% CI 0.20;0.67) per joint and ICC 0.56 (95% CI 0.49;0.62) per quadrant. The time to score one joint was mean 9.2 (SD 4.9) min.ConclusionsThis scoring method allows detection of small cortical interruptions on HR-pQCT imaging of finger joints, which is promising for use in clinical studies.

SAT0648 RELIABILITY OF MAGNETIC RESONANCE IMAGING (MRI)-SCORING OF THE METATARSOPHALANGEAL-JOINTS ACCORDING TO THE RHEUMATOID ARTHRITIS-MRI SCORE (RAMRIS)

SAT0222 COOPERATION OF T FOLLICULAR HELPER CELLS AND B CELLS IN TERTIARY LYMPHOID STRUCTURES IN TAKAYASU ARTERITIS

AB0471 ELEVATED EXPRESSION OF PYRUVATE KINASE M2 IN GIANT CELL ARTERITIS

Giant cell arteritis (GCA) is a subacute periarteritis predominantly affecting segments of the external carotids of elderly patients. Vasculitic lesions in GCA samples might be characterized by in situ production of cytokines mRNA, indicative of macrophage and T-cell activation. However, whether the cytokine production of vessels with arteritis differs from that of vessels exposed to inflammatory conditions that originate peripheral to the vessel remains unknown. We investigated cytokine and soluble receptor cytokine production in blood samples and cultures of human temporal arteries from 22 consecutive patients (mean age 77 +/- 6 years) further investigated for possible diagnosis of GCA: 7 patients had GCA and 15 had neither GCA nor vasculitis but had other inflammatory, infectious, or malignant diseases (controls). The production of cytokines and soluble cytokine receptors in the supernatants of cultures of 3-mm segments of temporal artery specimens, before and after lipopolysaccharide (LPS) stimulation (10 ng/ml and 10 microg/ml) and in serum, was quantified using sandwich enzyme-linked immunosorbent assay (ELISA). Cytokine production by temporal arteries increased significantly and in a dose-dependent manner (p <.01) after LPS stimulation in all patients studied, suggesting that the system is methodologically functional. Despite a large interindividual variation, we found similar differences in cytokine production before and after stimulation by 10 ng/ml and 10 microg/ml LPS between both groups: temporal arteries of GCA patients produced more interleukin (IL)-1beta (p <.05) and IFNgamma (nonsignificant) and less tumor necrosis factor (TNF)alpha (p <.05) and IL-6 (nonsignificant) than temporal arteries of controls. The levels of TNFalpha (p <.05) and IL-6 soluble receptor (p <.05) were significantly lower in GCA patients as compared with controls in blood samples, whereas levels of cytokines in temporal artery and in blood samples were not significantly correlated at the individual level in both groups. The present pilot study, which requires further confirmation on a larger number of well-defined patients with GCA, suggests that a specific arterial cytokine production profile might exist in GCA (high IL-1beta +/- IFNgamma and low TNFalpha), addresses the question of the mechanisms by which IL-1beta and TNFalpha might be differentially regulated at the level of the arterial cell wall, and supports the view that cultures of the temporal artery might be an interesting tool for evaluating the role of cytokines in GCA pathogenesis.

Quantitative diffusion-weighted imaging (DWI) MRI is a promising technique for cancer characterization and treatment monitoring. Knowledge of the reproducibility of DWI metrics in breast tumors is necessary to apply DWI as a clinical biomarker. To evaluate the repeatability and reproducibility of breast tumor apparent diffusion coefficient (ADC) in a multi-institution clinical trial setting, using standardized DWI protocols and quality assurance (QA) procedures. Prospective. In all, 89 women from nine institutions undergoing neoadjuvant chemotherapy for invasive breast cancer. DWI was acquired before and after patient repositioning using a four b-value, single-shot echo-planar sequence at 1.5T or 3.0T. A QA procedure by trained operators assessed artifacts, fat suppression, and signal-to-noise ratio, and determine study analyzability. Mean tumor ADC was measured via manual segmentation of the multislice tumor region referencing DWI and contrast-enhanced images. Twenty cases were evaluated multiple times to assess intra- and interoperator variability. Segmentation similarity was assessed via the Sørenson-Dice similarity coefficient. Repeatability and reproducibility were evaluated using within-subject coefficient of variation (wCV), intraclass correlation coefficient (ICC), agreement index (AI), and repeatability coefficient (RC). Correlations were measured by Pearson's correlation coefficients. In all, 71 cases (80%) passed QA evaluation: 44 at 1.5T, 27 at 3.0T; 60 pretreatment, 11 after 3 weeks of taxane-based treatment. ADC repeatability was excellent: wCV = 4.8% (95% confidence interval [CI] 4.0, 5.7%), ICC = 0.97 (95% CI 0.95, 0.98), AI = 0.83 (95% CI 0.76, 0.87), and RC = 0.16 * 10-3 mm2 /sec (95% CI 0.13, 0.19). The results were similar across field strengths and timepoint subgroups. Reproducibility was excellent: interreader ICC = 0.92 (95% CI 0.80, 0.97) and intrareader ICC = 0.91 (95% CI 0.78, 0.96). Breast tumor ADC can be measured with excellent repeatability and reproducibility in a multi-institution setting using a standardized protocol and QA procedure. Improvements to DWI image quality could reduce loss of data in clinical trials. 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;49:1617-1628.

AB0439 Contribution of anti-ferritin antibodies to the diagnosis of giant cell arteritis

PurposeTo evaluate the added value of ultra-short echo time (UTE) and fast field echo resembling a CT using restricted echo-spacing (FRACTURE) MR sequences in the assessment of the osseous cervical spine using CT as reference.Materials and methodsTwenty-seven subjects underwent postmortem CT and MRI within 48 h. Datasets were anonymized and analyzed retrospectively by two radiologists. Morphological cervical spine alterations were rated on CT, UTE and FRACTURE images. Afterward, neural foraminal stenosis was graded on standard MR and again after viewing additional UTE/FRACTURE sequences. To evaluate interreader and intermodality reliability, intra-class correlation coefficients (ICC) and for stenosis grading Wilcoxon-matched-pairs testing with multiple comparison correction were calculated.ResultsModerate interreader reliability (ICC = 0.48–0.71) was observed concerning morphological findings on all modalities. Intermodality reliability was good between modalities regarding degenerative vertebral and joint alterations (ICC = 0.69–0.91). Compared to CT neural stenosis grades were more often considered as nonsignificant on all analyzed MR sequences. Neural stenosis grading scores differed also significantly between specific bone imaging sequences, UTE and FRACTURE, to standard MR sequences. However, no significant difference was observed between UTE and FRACTURE sequences.ConclusionCompared to CT as reference, UTE or FRACTURE sequence added to standard MR sequences can deliver comparable information on osseous cervical spine status. Both led to changes in clinically significant stenosis gradings when added to standard MR, mainly reducing the severity of neural foramina stenosis.

BackgroundThe GUSTO (Giant cell arteritis (GCA) treatment with Ultra-Short glucocorticoids and TOcilizumab) trial evaluated the efficacy and safety of Tocilizumab (TCZ) monotherapy after a 3-day glucocorticoid-pulse in new-onset GCA [1]....

AB0041 CD8+ T CELLS HAVE AN ELEVATED PROLIFERATIVE CAPACITY IN GIANT CELL ARTERITIS

This study assessed diffusion abnormalities of the optic nerve (ON) in giant cell arteritis (GCA) patients with acute onset of visual impairment (VI) using diffusion-weighted magnetic resonance imaging (DWI). DWI scans of GCA patients with acute VI were evaluated in a case-control study. Two blinded neuroradiologists assessed randomized DWI scans of GCA and controls for ON restricted diffusion. Statistical quality criteria and inter-rater reliability (IRR) were calculated. DWI findings were compared to ophthalmological assessments. 35 GCA patients (76.2 ± 6.4 years; 37 scans) and 35 controls (75.7 ± 7.6 years; 38 scans) were included. ON restricted diffusion was detected in 81.1% (Reader 1) of GCA scans. Localization of ON restricted diffusion was at the optic nerve head in 80.6%, intraorbital in 11.1% and affecting both segments in 8.3%. DWI discerned affected from unaffected ON with a sensitivity, specificity, positive and negative predictive value of 87%/99%/96%/96%. IRR for ON restricted diffusion was κinter = 0.72 (95% CI 0.59–0.86). DWI findings challenged ophthalmologic diagnoses in 4 cases (11.4%). DWI visualizes anterior and posterior ON ischemia in GCA patients with high sensitivity and specificity, as well as substantial IRR. DWI may complement the ophthalmological assessment in patients with acute VI.

OP0156 Simple assessment of conventional 18f-fdg pet/ct accurately diagnoses cranial arteritis in glucocorticoid-naÏve gca patients: a case-control study