Quasi-real-time range monitoring by in-beam PET: a case for 15O

A fast and reliable range monitoring method is required to take full advantage of the high linear energy transfer provided by therapeutic ion beams like carbon and oxygen while minimizing damage to healthy tissue due to range uncertainties. Quasi-real-time range monitoring using in-beam positron emission tomography (PET) with therapeutic beams of positron-emitters of carbon and oxygen is a promising approach. The number of implanted ions and the time required for an unambiguous range verification are decisive factors for choosing a candidate isotope. An experimental study was performed at the FRS fragment-separator of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, to investigate the evolution of positron annihilation activity profiles during the implantation of [Formula: see text]O and [Formula: see text]O ion beams in a PMMA phantom. The positron activity profile was imaged by a dual-panel version of a Siemens Biograph mCT PET scanner. Results from a similar experiment using ion beams of carbon positron-emitters [Formula: see text]C and [Formula: see text]C performed at the same experimental setup were used for comparison. Owing to their shorter half-lives, the number of implanted ions required for a precise positron annihilation activity peak determination is lower for [Formula: see text]C compared to [Formula: see text]C and likewise for [Formula: see text]O compared to [Formula: see text]O, but their lower production cross-sections make it difficult to produce them at therapeutically relevant intensities. With a similar production cross-section and a 10 times shorter half-life than [Formula: see text]C, [Formula: see text]O provides a faster conclusive positron annihilation activity peak position determination for a lower number of implanted ions compared to [Formula: see text]C. A figure of merit formulation was developed for the quantitative comparison of therapy-relevant positron-emitting beams in the context of quasi-real-time beam monitoring. In conclusion, this study demonstrates that among the positron emitters of carbon and oxygen, [Formula: see text]O is the most feasible candidate for quasi-real-time range monitoring by in-beam PET that can be produced at therapeutically relevant intensities. Additionally, this study demonstrated that the in-flight production and separation method can produce beams of therapeutic quality, in terms of purity, energy, and energy spread.

Production and separation of positron emitters for hadron therapy at FRS-Cave M

The FRagment Separator FRS at GSI is a versatile spectrometer and separator for experiments with relativistic in-flight separated short-lived exotic beams. One branch of the FRS is connected to the target hall where the bio-medical cave (Cave M) is located. Recently a joint activity between the experimental groups of the FRS and the biophysics at the GSI and Department of physics at LMU was started to perform biomedical experiments relevant for hadron therapy with positron emitting carbon and oxygen beams. This paper presents the new ion-optical mode and commissioning results of the FRS-Cave M branch where positron emitting ¹⁵O-ions were provided to the medical cave for the first time. An overall conversion efficiency of 2.9±0.2×10^{-4 15}O fragments per primary ¹⁶O ion accelerated in the synchrotron SIS18 was reached.

Precision of the PET activity range during irradiation with10C,11C, and12C beams

Objective. Beams of stable ions have been a well-established tool for radiotherapy for many decades. In the case of ion beam therapy with stable¹²C ions, the positron emitters^10,11C are produced via projectile and target fragmentation, and their decays enable visualization of the beam via positron emission tomography (PET). However, the PET activity peak matches the Bragg peak only roughly and PET counting statistics is low. These issues can be mitigated by using a short-lived positron emitter as a therapeutic beam.Approach.An experiment studying the precision of the measurement of ranges of positron-emitting carbon isotopes by means of PET has been performed at the FRS fragment-separator facility of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany. The PET scanner used in the experiment is a dual-panel version of a Siemens Biograph mCT PET scanner.Main results.High-quality in-beam PET images and activity distributions have been measured from the in-flight produced positron emitting isotopes¹¹C and¹⁰C implanted into homogeneous PMMA phantoms. Taking advantage of the high statistics obtained in this experiment, we investigated the time evolution of the uncertainty of the range determined by means of PET during the course of irradiation, and show that the uncertainty improves with the inverse square root of the number of PET counts. The uncertainty is thus fully determined by the PET counting statistics. During the delivery of 1.6 × 10⁷ions in 4 spills for a total duration of 19.2 s, the PET activity range uncertainty for¹⁰C,¹¹C and¹²C is 0.04 mm, 0.7 mm and 1.3 mm, respectively. The gain in precision related to the PET counting statistics is thus much larger when going from¹¹C to¹⁰C than when going from¹²C to¹¹C. The much better precision for¹⁰C is due to its much shorter half-life, which, contrary to the case of¹¹C, also enables to include the in-spill data in the image formation.Significance. Our results can be used to estimate the contribution from PET counting statistics to the precision of range determination in a particular carbon therapy situation, taking into account the irradiation scenario, the required dose and the PET scanner characteristics.

Maintaining differential pressure gradients does not increase safety inside modern BSL-4 laboratories

This article discusses a previously unrecognized contradiction in the design of biosafety level-4 (BSL-4) suit laboratories, also known as maximum or high containment laboratories. For decades, it is suggested that both directional airflow and pressure differentials are essential safety measures to prevent the release of pathogens into the environment and to avoid cross-contamination between laboratory rooms. Despite the absence of an existing evidence-based risk analyses demonstrating increased safety by directional airflow and pressure differentials in BSL-4 laboratories, they were anchored in various national regulations. Currently, the construction and operation of BSL-4 laboratories are subject to rigorous quality and technical requirements including airtight containment. Over time, BSL-4 laboratories evolved to enormously complex technical infrastructures. With the aim to counterbalance this development towards technical simplification while still maintaining maximum safety, we provide a detailed risk analysis by calculating pathogen mitigation in maximum contamination scenarios. The results presented and discussed herein, indicate that both directional airflow or a differential pressure gradient in airtight rooms within a secondary BSL-4 containment do not increase biosafety, and are not necessary. Likewise, reduction of pressure zones from the outside into the secondary containment may also provide sufficient environmental protection. We encourage laboratory design professionals to consider technical simplification and policymakers to adapt corresponding legislation and regulations surrounding directional airflow and pressure differentials for technically airtight BSL-4 laboratories.

4He dose- and track-averaged linear energy transfer: Monte Carlo algorithms and experimental verification

Objective. In the present hadrontherapy scenario, there is a growing interest in exploring the capabilities of different ion species other than protons and carbons. The possibility of using different ions paves the way for new radiotherapy approaches, such as the multi-ions treatment, where radiation could vary according to target volume, shape, depth and histologic characteristics of the tumor. For these reasons, in this paper, the study and understanding of biological-relevant quantities was extended for the case of 4He ion. Approach. Geant4 Monte Carlo based algorithms for dose- and track-averaged LET (Linear Energy Transfer) calculations, were validated for 4He ions and for the case of a mixed field characterised by the presence of secondary ions from both target and projectile fragmentation. The simulated dose and track averaged LETs were compared with the corresponding dose and frequency mean values of the lineal energy, y D ¯ and y ¯ F , derived from experimental microdosimetric spectra. Two microdosimetric experimental campaigns were carried out at the Italian eye proton therapy facility of the Laboratori Nazionali del Sud of Istituto Nazionale di Fisica Nucleare (INFN-LNS, Catania, I) using two different microdosimeters: the MicroPlus probe and the nano-TEPC (Tissue Equivalent Proportional Counter). Main results. A good agreement of L ¯ d Total and L ¯ t Total with y ¯ D and y ¯ T experimentally measured with both microdosimetric detectors MicroPlus and nano-TEPC in two configurations: full energy and modulated 4He ion beam, was found. Significance. The results of this study certify the use of a very effective tool for the precise calculation of LET, given by a Monte Carlo approach which has the advantage of allowing detailed simulation and tracking of nuclear interactions, even in complex clinical scenarios.

POS0153 MRI SPINAL LESIONS IN PATIENTS WITHOUT MRI OR RADIOGRAPHIC LESIONS IN THE SACROILIAC JOINTS TYPICAL OF AXIAL SPONDYLOARTHRITIS

Background

There are limited data as to the frequency of spinal lesions on MRI in patients without MRI or radiographic features typical of sacroiliac joint (SIJ) disease and to what degree spine MRI might enhance diagnostic evaluation.

Objectives

To assess the frequency of MRI lesions of the spine in the ASAS-Classification Cohort according to the presence of MRI SIJ lesions typical of axSpA and/or radiographic sacroiliitis (mNY+).

Methods

MRI spine lesions were recorded by 9 central readers in an eCRF that captures global assessment of the spine (“Is the MRI consistent with axSpA: yes/no”) (yes=MRIglobal spine+) and detailed anatomical-based scoring of each discovertebral unit plus lateral and posterior structures. Independently, readers globally assessed SIJ scans for active and/or structural lesions typical of axSpA. We compared the frequency of MRIglobal spine+ and frequencies of different types of spinal lesions according to the presence/absence of axSpA on global evaluation of SIJ scans by ≥5 of 9 readers (MRIglobal SIJ+) and mNY+ sacroiliitis using Fisher’s exact test. Analysis was also stratified by rheumatologist diagnosis.

Results

Among 51 cases with SIJ as well as spine MRI scans and radiographs of the SIJ,19 (37.3%) had MRIglobal SIJ+, and 12 (23.5%) and 7 (13.7%) had MRIglobal spine+ by ≥2 and ≥5 reader agreement, respectively. MRIglobal spine+ occurred significantly more frequently in the presence of mNY+ sacroiliitis and MRIglobal SIJ+ but was also recorded in 4 of 32(12.5%) (≥2 readers) and 1 of 32(3.4%) (≥5 readers) cases that were MRIglobal SIJ- and x-ray negative, all 4 cases being diagnosed with axSpA. Moreover, vertebral corner BME lesions, but not spinal structural lesions, were significantly more frequent in MRIglobal SIJ- cases that had been clinically diagnosed as axSpA versus non-axSpA (Table 1).

Table 1.

Frequency of Spinal MRI lesions According to SIJ Imaging Positive for AxSpA

MRI Spinal Lesions, N (%)MRIglobalSIJ+ (n=19)MRIglobalSIJ- (n=32)P valueMRIglobal SIJ+ and/or mNY+ (n=22)MRIglobal SIJ- and mNY- (n=29)P valueMRIglobal SIJ- and SpA Diagnosis+(n=17)MRIglobal SIJ- and SpA Diagnosis- (n=15)P valueMRIglobal consistent with axSpA (≥2/9 readers agree)8 (42.1%)4 (12.5%)0.048(36.4%)4(13.8%)0.104 (23.5%)0 (0%)0.10MRIglobal consistent with axSpA (≥5/9 readers agree)6 (31.6%)1 (3.1%)0.016 (27.3%)1 (3.4%)0.031 (5.9%)0 (0%)1.0VC BME ≥19 (47.4%)15 (46.9%)46.9% RT 62.5% CT 29.4% GT1.010(45.5%)14(48.3%)1.011 (64.7%)4 (26.7%)0.04VC BME ≥26 (31.6%)10 (31.3%)31.2% RT 55.6% CT 19.6% GT1.06(27.3%)10(34.5%)0.769 (52.9%)1 (6.7%)0.007VC BME ≥36 (31.6%)7 (21.9%)21.9% RT 53.8% CT 13.7% GT0.526(27.3%)7(24.1%)1.07 (41.2%)0 (0%)0.008VC BME ≥45 (26.3%)5 (15.6%)0.475(22.7%)5(17.2%)0.735 (29.4%)0 (0%)0.046Vertebral Endplate BME ≥12 (10.5%)3 (9.4%)1.02(9.1%)3(10.3%)1.02 (11.8%)1 (6.7%)1.0Lateral vertebral BME3 (15.8%)3 (9.4%)0.663(13.6%)3(10.3%)1.03 (17.6%)0 (0%)0.23Facet BME ≥14 (21.1%)1 (3.1%)3.1% RT 20.0% CT 2.0% GT0.064(18.2%)1(3.4%)0.151 (5.9%)0 (0%)1.0Posterior BME ≥15 (26.3%)2 (6.3%)0.095(22.7%)2(6.9%)0.221 (5.9%)1 (6.7%)1.0VC Fat ≥18 (42.1%)42.1% RT 44.4% CT 15.7% GT10 (31.3%)31.2% RT 55.6% CT 19.6% GT0.558(36.4%)10(34.5%)1.05 (29.4%)5 (33.3%)1.0VC Fat ≥27 (36.8%)5 (15.6%)0.107(31.8%)5(17.2%)0.323 (17.6%)2 (13.3%)1.0VC Fat ≥36 (31.6%)31.6% RT 66.7% CT 11.8% GT3 (9.4%)0.066(27.3%)3(10.3%)0.151 (5.9%)2 (13.3%)0.59VC Fat ≥46 (31.6%)1 (3.1%)0.016(27.3%)1(3.4%)0.030 (0%)1 (6.7%)0.47Lateral Fat ≥16 (31.6%)2 (6.3%)0.046(27.3%)2(6.9%)0.060 (0%)2 (13.3%)0.21Erosion ≥13 (15.8%)2 (6.3%)0.353(13.6%)2(6.9%)0.641 (5.9%)1 (6.7%)1.0Bone Spur ≥14 (21.1%)5 (15.6%)0.714(18.2%)5(17.2%)1.04 (23.5%)1 (6.7%)0.34Ankylosis ≥12 (10.5%)0 (0%)0.132(9.1%)0(0%)0.180 (0%)0 (0%)-

Conclusion

Spinal lesions on MRI indicative of axSpA per majority read occurred in about 3% of patients without positive imaging in the SIJ. Frequency of spinal BME lesions was higher in cases with negative SIJ imaging but clinically diagnosed with axSpA.

Disclosure of Interests

None declared

OP0150 ASAS RECOMMENDATIONS FOR REQUESTING AND REPORTING IMAGING EXAMINATIONS IN PATIENTS WITH SUSPECTED AXIAL SPONDYLOARTHRITIS

Background

Clinicians face uncertainties in their daily practice when requesting imaging examinations for patients with suspected axial spondyloarthritis (axSpA) or when producing an imaging report because the requirements and desired information of radiologists and rheumatologists / orthopedics alike are sometimes not completely known or understood.

Objectives

This project aimed to develop practical consensus recommendations for the standardized communication around imaging of sacroiliac joints and spine for diagnostic purposes in patients with suspected axSpA or their management in clinical practice.

Methods

An international task force was established combining radiologists (n=7) and rheumatologists (n=13) from the Assessment of SpondyloArthritis international Society (ASAS), two members of Young ASAS and a patient representative. The task force defined the project’s aims and developed a project statement. Then, considering published literature and the work of other groups, two survey rounds were designed, and all ASAS members invited to respond: first, to identify items for further consideration, second, to consider the detail of information to be communicated. Finally, ASAS members discussed the recommendations proposed by the task force during the ASAS annual workshop in January 2022 and voted regarding endorsement of the recommendations.

Results

The final set of recommendations is presented in Figure 1. Six recommendations deal with imaging requests in patients with axSpA. The first three recommendations entail clinical features, patients’ symptoms and risk factors. Recommendation 4 concerns previous imaging and reports and recommendation 5 refers to contraindications to imaging or contrast media. Recommendation 6 is about the suspected diagnosis and possible clinical differential diagnoses and the reason for the examination. Eleven additional recommendations refer to the radiology report. The first point addresses clinical information included in the report. Recommendations 2 to 4 advise on information about the technical conduct of the exam, the use of contrast media and image quality. Imaging findings that should be mentioned in the report if present are listed in recommendations 5 to 7. Finally, recommendations 8 to 11 combine advice for the conclusion, and for suggesting additional imaging or referral to a rheumatology expert if a different physician requested the imaging. The recommendations were endorsed by ASAS with approval from 73% of voting members (43 agreed, 10 rejected, 6 abstained).

Figure 1.

ASAS recommendations for requesting and reporting imaging in patients with suspected axial Spondyloarthritis.

Conclusion

These ASAS recommendations provide guidance for requesting and reporting imaging examinations in the context of axSpA and for standardizing and enhancing communication between rheumatologists and radiologists to improve diagnosis and patient care.

Disclosure of Interests

Torsten Diekhoff Paid instructor for: Novarits, Eli Lilly, MSD, Canon MS, Consultant of: Eli Lilly, Iris Eshed: None declared, Chiara Giraudo: None declared, Kay-Geert Hermann: None declared, Manouk de Hooge: None declared, Lennart Jans: None declared, Anne Grethe Jurik: None declared, Robert G Lambert: None declared, Pedro M Machado: None declared, Walter P Maksymowych: None declared, Michael Mallinson: None declared, Helena Marzo-Ortega: None declared, Victoria Navarro-Compán: None declared, Susanne Juhl Pedersen: None declared, Mikkel Østergaard: None declared, Monique Reijnierse: None declared, Martin Rudwaleit: None declared, Fernando Sommerfleck: None declared, Ulrich Weber: None declared, Xenofon Baraliakos: None declared, Denis Poddubnyy: None declared

POS1101 THE OMERACT KNEE INFLAMMATION MRI SCORING SYSTEM: VALIDATION OF QUANTITATIVE METHODOLOGIES AND TRI-COMPARTMENTAL OVERLAYS BY COMPARISON WITH THE MRI OSTEOARTHRITIS KNEE SCORE

Background:

Randomized controlled trials have targeted reducing the size of BML and degree of synovitis for the treatment of OA. We have developed the OMERACT Knee Inflammation MRI Scoring System (KIMRISS) and have recently refined it to maximize reliability and sensitivity to change. Innovations include electronic overlays for assessment of BML in 500 subregions, a web-based interface with direct online scoring, and real-time iterative calibration (RETIC) prior to reading exercises. Synovitis-effusion (S-E) is also scored on all consecutive sagittal slices on a web-based interface.

Objectives:

We aimed to test the feasibility, reliability, and responsiveness of KIMRISS versus an established method, MOAKS, in two multi-reader exercises.

Methods:

KIMRISS incorporates web-based graphic overlays for each of femur, tibia, and patella (range 0-500). S-E is recorded as the largest diameter perpendicular to the longest axis of this feature (range 0-100). All scores are pro-rated for a standardized number of MRI slices. In a pre-reading exercise for KIMRISS, readers scored sufficient cases in RETIC to attain scoring proficiency, pre-specified as an ICC of ≥0.80 and ≥0.70 for status and change scores of BML and S-E compared to developer reads. A new web-based scoring platform with overlays designating different subregions for scoring BML was developed for MOAKS. We compared reliability for status and change scores of BML and S-E in 2 international multi-reader exercises of baseline and one-year MRI scans from the Osteoarthritis Initiative: A. 4 expert readers and an OMERACT fellow scored 38 cases selected for MOAKS BML score ≥1. B. 7 expert readers and an OMERACT fellow scored 60 cases selected for MOAKS BML ≥3 and Kellgren-Lawrence (K-L) grade <3. Reliability was assessed by intra-class correlation coefficient (ICC) and Smallest Detectable Change (SDC), responsiveness by the standardized response mean (SRM), and feasibility using the System Usability Scale (SUS scoring range 0-100).

Results:

For exercises A/B, subjects were 55.3%/ 26.7% male, mean(±SD) age 61.7(±9.1)/61.9(8.8) years, and radiographic K-L grade ≤2 in 39.4%/100%. Change was small in both exercises (<5% of scoring range for KIMRISS and MOAKS BML and S-E) with comparable responsiveness (Table 1). Despite this, ICC for change was consistently good to very good for both BML and S-E and consistently better for KIMRISS (Table 1). Mean SUS scores were 88.2 for KIMRISS and 54.3 for MOAKS.

Table 1.

KIMRISS and MOAKS scores in Two International Multi-reader Exercises

MethodMRI featureScores mean (SD)SDC(% of max)P valueSRMBaselineOne-year Follow upChangeEXERCISE AMOAKSBML3.6 (2.9)3.4 (2.3)-0.2 (1.9)1.0 (2.2%)0.72-0.11Synovitis-effusion1.3 (0.8)1.5 (0.8)0.2 (0.4)0.4 (13.3%)0.0170.5KIMRISSBML15.7 (13.3)21.2 (22.5)5.5 (15.3)5.6 (1.1%)0.0220.36Synovitis-effusion21.8 (12.0)24.3 (11.9)2.5 (7.4)2.8 (2.8%)0.0430.34EXERCISE BMOAKSBML4.2 (2.6)3.7 (2.4)-0.5 (2.1)1.1 (2.4%)0.083-0.24Synovitis-effusion1.2 (0.7)1.3 (0.8)0.0 (0.5)0.4 (13.3%)0.590.0KIMRISSBML18.0 (17.5)15.9 (14.3)-2.1 (12.3)5.9 (1.2%)0.19-0.17Synovitis-effusion21.8 (9.3)22.9 (10.8)1.1 (7.1)2.2 (2.2%)0.250.15Intra-class Correlation Coefficients (95%CI)MethodMRI featureExercise AExercise BKIMRISS statusKIMRISS changeBML0.86 (0.78-0.92)0.88 (0.81-0.93)0.80 (0.70-0.87)0.72 (0.64-0.80)MOAKS statusMOAKS changeBML0.71 (0.46-0.85)0.76 (0.64-0.85)0.67 (0.56-0.77)0.69 (0.60-0.78)KIMRISS statusKIMRISS changeSynovitis-effusion0.88 (0.81-0.93)0.87 (0.79-0.92)0.75 (0.52-0.86)0.87 (0.82-0.91)MOAKS statusMOAKS changeSynovitis-effusion0.66 (0.4-0.79)0.52 (0.36-0.67)0.65 (0.52-0.75)0.48 (0.37-0.60)

Conclusion:

The KIMRISS method for scoring BML and Synovitis-Effusion scores highly for feasibility and demonstrates consistently high reliability when compared to MOAKS. Further validation for responsiveness is necessary in cases with greater change in MRI features than in the OAI dataset.

Disclosure of Interests:

None declared.

POS0032 SCORING MRI STRUCTURAL LESIONS IN SACROILIAC JOINTS OF PATIENTS WITH AXIAL SPONDYLOARTHRITIS: HOW MANY SLICES ARE OPTIMAL?

Background:

There is no international consensus on the optimal number of slices for evaluation of MRI structural lesions in the SIJ. An “all slice” method evaluates lesions from the most anterior slice, defined as the first slice with vertical height of ≥1cm of the SIJ joint cavity, up to the most posterior slice, defined as the most posterior slice where ≥1cm vertical height of the cartilaginous portion is still visible. The SPARCC method scores the transitional slice between cartilaginous and ligamentous compartments as the first slice and then an additional 4 slices anterior to the transitional slice.

Objectives:

We aimed to investigate inter-reader reliability, the extent of detection of lesions, and frequency of cases with a positive MRI for structural lesions when using an “all slice” approach versus the SPARCC scoring of 5 central slices.

Methods:

MRI T1W images with DICOM series were available from 148 cases who had MRI performed in the ASAS-Classification Cohort. Seven central readers recorded MRI lesions in an eCRF that recorded global assessments of presence/absence of changes suggestive of axSpA and structural lesions typical of axSpA. Structural lesions per the ASAS definitions were also recorded in consecutive semicoronal slices using the “all slice” approach, but also recording the transitional slice, according to their presence/absence in SIJ quadrants (erosion, fat lesion, sclerosis) or halves (backfill, ankylosis). Structural lesion frequencies were assessed descriptively according to majority agreement (≥4/7) of central readers and also any 2 central readers. Reliability for detection of MRI lesions was compared between central and local readers using the ICC.

Results:

The mean (SD) (range) number of anterior and posterior slices peripheral to the 5 central slices was 1.0 (1.0) (0-4) and 2.2 (1.8) (0-6) per case, respectively. There were 2 cases (1.4%) where ≥2 readers scored structural lesions in peripheral slices but not in the 5 central slices. The mean percentage of the total structural lesion score that was captured by the 5 central slices was >75% for all types of lesions except ankylosis (59%) (Table 1). Inter-reader reliability was greater for all lesions when assessing the 5 central slices and especially for erosion and backfill (Table 1).

Conclusion:

The major component of structural lesion data is captured by assessment of 5 slices, which includes the transitional slice and the subsequent 4 anterior slices. Moreover, reliability for detection of structural lesions is substantially worse in peripheral slices.

MRI Lesion“All slice”Central 5 slicesPeripheral slicesP value central vs peripheral slicesP value“all slice” vs central slicesMean (SD) Lesion Score Per CaseErosion2.4 (4.5) (0-22.9)1.8(3.4) (0-17.1)0.6 (1.4) (0-10.1)<0.001< 0.001Fat lesion2.5 (5.9) (0-34.0)1.8 (4.5) (0-25.1)0.7 (1.8) (0-9.9)< 0.001<0.001Sclerosis2.0 (4.9) (0-39.0)1.5 (3.6) (0-26.1)0.5 (1.5) (0-12.9)< 0.001<0.001Backfill0.5 (1.5) (0-12)0.4 (1.2) (0.0-9.3)0.1 (0.4) (0-2.7)< 0.0010.84Ankylosis0.5 (3.4) (0-30.7)0.3 (2.3) (0-20.0)0.2 (1.2) (0-11.3)0.100.18Mean (SD) (Range) % of Total Lesion Score in Central vs Peripheral slicesErosion100%76.4% (28.9%) (0-100%)23.6% (28.9%) (0-100%)<0.001NAFat lesion100%75.4% (26.5%) (0-100%)24.6% (26.5%) (0-100%)<0.001NASclerosis100%79.5% (22.9%) (0-100%)20.5% (22.9%) (0-100%)<0.001NABackfill100%86.0% (20.2%) (0-100%)14.0% (20.2%)(0-100%)<0.001NAAnkylosis100%59.0% (36.4%) (0-100%)41.0% (36.4%) (0-100%)0.56NAICC of 7 readers (Mean (SD) (Range))MRI lesionAll slicesCentral 5 slicesPeripheral slicesErosion0.54 (0.15) (0.28-0.84)0.58 (0.13) (0.34-0.85)0.40 (0.17) (0.10-0.66)Fat lesion0.61 (0.18) (0.30-0.89)0.63 (0.16) (0.35-0.88)0.52 (0.20) (0.19-0.82)Sclerosis0.73 (0.18) (0.36-0.94)0.73 (0.16) (0.36-0.91)0.67 (0.19) (0.27-0.94)Backfill0.37 (0.21) (0.10-0.85)0.39 (0.19) (0.14-0.83)0.18 (0.23) (0.0-0.80)Ankylosis0.97 (0.02) (0.91-0.99)0.99 (0.01) (0.97-1.0)0.85 (0.10) (0.62-0.98)

Disclosure of Interests:

None declared.

OP0251 DATA-DRIVEN DEFINITIONS BASED ON INFLAMMATORY LESIONS FOR A POSITIVE MRI OF THE SPINE CONSISTENT WITH AXIAL SPONDYLOARTHRITIS

Background:

The ASAS definition of a positive MRI for inflammation in the spine (ASAS-MRIspine+) is intended for classification of patients as having axSpA but is often misused for diagnostic purposes. This is problematic because bone marrow edema (BME) in the spine may occur in 20-40% of those with mechanical back disorders. The ASAS MRI group has generated updated consensus lesion definitions which have been validated on MRI spine images from the ASAS Classification Cohort.

Objectives:

We aimed to identify quantitative cut-offs based on numbers of vertebral corners that define ASAS-MRIspine+, there being two gold standards: A. majority central reader decision as to the presence of spine MRI findings consistent with axSpA B. rheumatologist expert opinion diagnosis of axSpA.

Methods:

Eight ASAS-MRI readers recorded MRI lesions in the spine according to recently updated ASAS definitions from 62 cases in an eCRF that comprises global assessment (MRI consistent with axSpA? (yes/no)), and detailed scoring of lesions for all sites in the spine. We calculated sensitivity and specificity for numbers of vertebral corners with BME where a majority of readers (≥5/8) agreed as to the presence of MRI findings consistent with axSpA. We selected cut-offs with ≥95% specificity. These cut-offs were analyzed for their predictive utility for rheumatologist diagnosis of axSpA by calculating positive and negative predictive values (PPV, NPV) and selecting cut-offs with PPV ≥95%. Both criteria were considered requirements for designation of MRI cut-offs defining ASAS-MRIspine+.

Results:

MRI findings consistent with axSpA were observed by majority read in 8 (20%) of 40 cases diagnosed with axSpA, and 0 (0%) of 19 cases without axSpA. Cut-offs achieving specificity of ≥95% for MRI findings consistent with axSpA were 4 vertebral corners (sensitivity 75%) for all cases, 3 vertebral corners (sensitivity 37.5%) for cases with ≥1 additional location with inflammation, 1 vertebral corner (sensitivity 62.5%) in cases with ≥2 vertebral corner fat lesions (Table 1). All of the above cut-offs also had very high PPV (≥95%) for diagnosis of axSpA in cases diagnosed by the rheumatologist (Table 2).

Table 1.

Majority readers agree MRI findings consistent with axSpA are present is the gold-standard external reference

MRI cut-offsSensitivity (95%CI)Specificity (95%CI)BME in ≥2 vertebral corners87.5 (47.3 - 99.7)87.0 (75.1 - 94.6)BME in ≥ 3 vertebral corners87.5 (47.3 - 99.7)94.4 (84.6 - 98.8)BME in ≥4 vertebral corners75.0 (34.9 - 96.8)98.2 (90.1 - 100.0)Cases with ≥1 additional non-corner site inflammatory lesionBME in ≥2 vertebral corners37.5 (8.5 - 75.5)94.4 (84.6 - 98.8)BME in ≥3 vertebral corners37.5 (8.5 - 75.5)98.2 (90.1-100.0)Cases with ≥2 vertebral corner fat lesionsBME in ≥1 vertebral corner62.5 (24.5 - 91.5)100.0 (93.4-100.0)BME in ≥2 vertebral corners62.5 (24.5 - 91.5)100.0 (93.4-100.0)Table 2.

Predictive values of cut-offs for number of vertebral corners with BME according to the diagnostic ascertainment of the rheumatologist

MRI cut-offsSensitivity (95%CI)Specificity (95%CI)PPVNPVMRI findings consistent with axSpA ≥any 2 readers52.5 (36.1 - 68.5)94.7 (74.0 - 99.9)95.5 (75.3 - 99.3)48.6 (40.2 - 57.2)MRI findings consistent with axSpA ≥majority read20.0 (9.1 - 35.6)100.0 (82.4 - 100.0)100.037.3 (33.7 - 40.9)BME in ≥ 4 vertebral corners17.5 (7.3 - 32.8100.0 (82.4 - 100.0)100.036.5 (33.3 - 39.9)Cases with ≥1 additional inflammatory lesionBME in ≥ 3 vertebral corners10.00 (2.8 - 23.7)100.00 (82.4 - 100.0)100.034.5 (32.2 - 36.9)Cases with ≥2 vertebral corner fat lesionsBME in ≥1 vertebral corner12.50 (4.2 - 26.8)100.00 (82.4 - 100.0)100.035.2 (32.6 - 37.9)

Conclusion:

A cut-off of BME in ≥4 vertebral corners, or ≥3 corners in the setting of additional inflammatory lesions at other locations or corner fat, are primary candidates for defining ASAS-MRIspine+. These cut-offs apply to typical patients referred to a rheumatologist with a high index of suspicion of axSpA and may not be appropriate in other populations.

Disclosure of Interests:

None declared

POS0037 DOES IMAGING OF THE SACROILIAC JOINT DIFFER IN PATIENTS PRESENTING WITH UNDIAGNOSED BACK PAIN AND PSORIASIS, ACUTE ANTERIOR UVEITIS, AND COLITIS: AN INCEPTION COHORT STUDY

Background:

Axial spondyloarthritis (axSpA) presents diagnostic challenges incurring a delay of up to a decade and relies considerably on radiographic and MRI evidence of sacroiliitis which has led to the development of classification criteria which also rely on imaging. However, it has been suggested that such criteria may not be appropriate for axSpA patients presenting with other forms of SpA, especially psoriatic, because imaging features may vary in frequency and/or may be atypical. This hypothesis has never been tested in a prospective inception cohort of patients presenting with undiagnosed back pain.

Objectives:

We aimed to compare the spectrum of radiographic and MRI abnormalities in the sacroiliac joint (SIJ) of an inception cohort of patients presenting with undiagnosed back pain and psoriasis, iritis, and colitis.

Methods:

We used data from the prospective multicenter Screening for Axial Spondyloarthritis in Psoriasis, Iritis, and Colitis (SASPIC) Study, which is aimed at early detection of axial SpA in patients referred by the respective specialist after first presenting with these disorders. Consecutive patients ≤45 years of age with ≥3 months undiagnosed back pain with any one of psoriasis, AAU, or colitis undergo routine clinical evaluation by a rheumatologist for axial SpA followed by imaging. In SASPIC I, MRI evaluation of the SIJ was ordered per rheumatologist decision. In SASPIC II, MRI evaluation was ordered for all patients. Radiographs and MRI scans were assessed by two central readers and comparisons of the three groups were based on concordant assessments of imaging features. Evaluation of MRI scans included both global assessment for presence/absence of axSpA with confidence scale (-10 to +10), active and structural lesions typical of axSpA per recent ASAS definitions, and granular assessment of individual lesions according to SIJ quadrants and halves in consecutive semicoronal slices through the SIJ. Groups were compared by ANOVA and the chi-square test.

Results:

A total of 240 patients were recruited, 143 from SASPIC I and 97 from SASPIC II, 101 (42.1%) being diagnosed with axSpA (65.3% male, mean age 34.4 years, mean symptom duration 8.7 years, B27 positive 55.4%). Mean age of colitis (N=101), psoriasis (N=61), iritis (N=78) patients were 33.4, 36.6, 34.3 years, respectively, mean symptom duration was 6.8, 7.2, 9.4 years, respectively, and % males were 45.5%, 52.5%, 51.3%, respectively. There were no significant group differences for unilateral versus bilateral radiographic sacroiliitis and no significant differences in the frequencies, type, or distribution of MRI lesions (Table 1).

Conclusion:

Data from the SASPIC prospective inception cohort does not support the view that imaging of the SIJ differs in psoriatic axSpA, which appears similar to axSpA associated with iritis or colitis. These data support the umbrella concept of axSpA.

Imaging FeatureColitis (n=30)Psoriasis (n=19)Iritis (n=52)P valueUnilateral sacroiliitis (grade ≥2), N(%)1 (3.3%)0 (0%)2 (3.8%)0.69mNY criteria +, N(%)5 (16.7%)6 (31.2%)15 (28.8%)0.39Grade of sacroiliitis, mean(SD)1.8 (2.2)2.1 (2.7)2.2 (2.4)0.76MRI indicative of axSpA, N(%)15 (50.0%)11 (57.9%)32 (61.5%)0.60MRI indicative of axSpA (confidence ≥5/10), N(%)14 (46.7%)10 (52.6%)30 (57.7%)0.63MRI active lesion typical of axSpA, N(%)6 (20.0%)6 (31.6%)18 (34.6%)0.37MRI structural lesion typical of axSpA, N(%)11 (36.7%)7 (36.8%)18 (34.6%)0.98MRI with unilateral lesion (any)2 (6.7%)3 (15.8%)11 (21.2%)0.22MRI with unilateral lesion (BME)1 (3.3%)2 (10.5%)5 (9.6%)0.54MRI with unilateral lesion (Erosion)0 (0%)0 (0%)3 (5.8%)0.23MRI with unilateral lesion (Sclerosis)1 (3.3%)1 (5.3%)3 (5.8%)0.89MRI with unilateral lesion (Fat)0 (0%)0 (0%)0 (0%)NAMRI with iliac lesion17 (56.7%)12 (63.2%)32 (61.5%)0.88MRI with sacral lesion12 (40.0%)11 (57.9%)31 (59.6%)0.21

Disclosure of Interests:

Walter P Maksymowych Speakers bureau: Abbvie, Janssen, Novartis, Pfizer, UCB, Consultant of: Abbvie, BMS, Boehringer, Galapagos, Gilead, Lilly, Novartis, Pfizer, UCB, Grant/research support from: Abbvie, Novartis, Pfizer, Ulrich Weber: None declared, Jon Chan: None declared, Raj Carmona: None declared, James Yeung: None declared, Sibel Aydin: None declared, Jodie Reis: None declared, Liam Martin: None declared, Ariel Masetto: None declared, Olga Ziouzina: None declared, Dianne Mosher: None declared, Stephanie Keeling: None declared, Sherry Rohekar: None declared, Rana Dadashova: None declared, Joel Paschke: None declared, Amanda Carapellucci: None declared, Robert G Lambert: None declared.

Impacts of extreme summers on European ecosystems: a comparative analysis of 2003, 2010 and 2018

In Europe, three widespread extreme summer drought and heat (DH) events have occurred in 2003, 2010 and 2018. These events were comparable in magnitude but varied in their geographical distribution and biomes affected. In this study, we perform a comparative analysis of the impact of the DH events on ecosystem CO₂ fluxes over Europe based on an ensemble of 11 dynamic global vegetation models (DGVMs), and the observation-based FLUXCOM product. We find that all DH events were associated with decreases in net ecosystem productivity (NEP), but the gross summer flux anomalies differ between DGVMs and FLUXCOM. At the annual scale, FLUXCOM and DGVMs indicate close to neutral or above-average land CO₂ uptake in DH2003 and DH2018, due to increased productivity in spring and reduced respiration in autumn and winter compensating for less photosynthetic uptake in summer. Most DGVMs estimate lower gross primary production (GPP) sensitivity to soil moisture during extreme summers than FLUXCOM. Finally, we show that the different impacts of the DH events at continental-scale GPP are in part related to differences in vegetation composition of the regions affected and to regional compensating or offsetting effects from climate anomalies beyond the DH centres. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.

SAT0378 THE RELATIVE DIAGNOSTIC UTILITY OF INFLAMMATORY BACK PAIN CRITERIA IN AN INCEPTION COHORT OF PATIENTS WITH PSORIASIS, IRITIS, AND COLITIS PRESENTING WITH UNDIAGNOSED BACK PAIN

Background:

Clinicians rely on the elicitation of features of inflammatory back pain (IBP) for diagnosis of axial spondyloarthritis (axSpA) but the utility of IBP criteria in patients presenting with extra-articular features of axSpA remains unclear. Assessment of utility should include not only rheumatologist diagnosis as benchmark but imaging to address the circularity between elicitation of IBP and clinical diagnosis.

Objectives:

To assess the diagnostic utility of all criteria for IBP in patients with psoriasis, iritis, or colitis and undiagnosed back pain using the rheumatologist diagnosis and imaging as benchmarks.

Methods:

Consecutive patients (n=246) with undiagnosed back pain ≤45 years of age, ≥3 months, with any one of psoriasis (n=46), acute anterior uveitis (AAU)(n=73), or colitis (n=127) had diagnostic evaluation by a rheumatologist. Majority central reader assessment of MRI indicative of axSpA and diagnosis by the rheumatologist were external standards for testing the utility of these IBP criteria: ASAS, Berlin, Calin, rheumatologist global for IBP >5 (0-10 scale).

Results:

AxSpA was diagnosed in 44.4%, 61.6%, and 41.8% of patients with psoriasis, iritis, and IBD, respectively. Diagnostic utility for all IBP criteria was comparably poor (Table 1). MRI was indicative of axSpA in 21.2%, 43.5%, and 19.7% of patients with psoriasis, iritis, and IBD. The utility of the IBP criteria was even worse using MRI as the external reference (Table 2), especially in patients with psoriasis. Only 14% of psoriasis patients with a positive MRI reported “improvement with exercise but not rest” as compared to 70% and 62% of patients with iritis and IBD, respectively.

Table 1.

Rheumatologist diagnosis as external reference.

SensitivitySpecificityLR+LR-PsoriasisASAS IBP65.00%52.00%1.350.67Berlin IBP80.00%36.00%1.250.56Calin IBP80.00%28.00%1.110.71All 3 criteria sets60.00%56.00%1.360.71IBP global >585.00%36.00%1.330.42AAUASAS IBP84.44%42.86%1.480.36Berlin IBP80.00%57.14%1.870.35Calin IBP93.33%17.86%1.140.37All 3 criteria sets77.78%60.71%1.980.37IBP global >586.67%57.14%2.020.23IBDASAS IBP78.43%45.07%1.430.48Berlin IBP82.35%52.11%1.720.34Calin IBP84.31%19.72%1.050.80All 3 criteria sets70.59%57.75%1.670.51IBP global >580.39%66.20%2.380.30Table 2.

Central assessment that MRI is indicative of axSpA as external reference.

SensitivitySpecificityLR+LR-PsoriasisASAS IBP28.57%38.46%0.461.86Berlin IBP42.86%15.38%0.513.71Calin IBP71.43%23.08%0.931.24All 3 criteria sets14.29%42.31%0.252.03IBP global >585.71%23.08%1.110.62AAUASAS IBP75.00%26.92%1.030.93Berlin IBP70.00%38.46%1.140.78Calin IBP90.00%15.38%1.060.65All 3 criteria sets65.00%38.46%1.060.91IBP global >575.00%38.46%1.220.65IBDASAS IBP92.31%37.74%1.480.20Berlin IBP76.92%39.62%1.270.58Calin IBP92.31%16.98%1.110.45All 3 criteria sets76.92%45.28%1.410.51IBP global >592.31%47.17%1.750.16

Conclusion:

All IBP criteria have poor diagnostic utility for diagnosis of axSpA, especially in patients with psoriasis. This reinforces the desirability of less subjective assessment tools, especially imaging.

Disclosure of Interests:

Georg Kröber: None declared, Ulrich Weber: None declared, Raj Carmona: None declared, James Yeung: None declared, Jon Chan: None declared, Sibel Aydin: None declared, Liam Martin: None declared, Ariel Masetto: None declared, Stephanie Keeling: None declared, Olga Ziouzina: None declared, Sherry Rohekar: None declared, Rana Dadashova: None declared, Joel Paschke: None declared, Amanda Carapellucci: None declared, Robert G Lambert: None declared, Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB

FRI0298 ASAS MODIFICATION OF THE BERLIN ALGORITHM AND THE DUET ALGORITHM FOR DIAGNOSING AXIAL SPONDYLOARTHRITIS: RESULTS FROM THE SCREENING IN AXIAL SPONDYLOARTHRITIS FOR PSORIASIS, IRITIS, AND COLITIS COHORT

Background:

Patients presenting with back pain and psoriasis, iritis, or colitis, represent a high-risk population for the presence of axial spondyloarthritis (axSpA). The Dublin Evaluation Tool (DUET)1, the Berlin algorithm2, and the ASAS modification of this algorithm3are recommended referral strategies aimed at early diagnosis of axSpA. DUET was developed for patients presenting with AAU. Validation of these algorithms in inception cohorts is limited.

Objectives:

1. To assess the performance of referral algorithms for diagnosis of axSpA when tested against the final local rheumatologist diagnosis in an inception cohort of patients presenting with undiagnosed back pain and extra-articular manifestations. 2. To determine whether different criteria for inflammatory back pain (IBP) impact the performance of the algorithms.

Methods:

The multicenter Screening for Axial Spondyloarthritis in Psoriasis, Iritis, and Colitis (SASPIC) Study at 11 sites is aimed at early detection of axial SpA in patients presenting with undiagnosed back pain to the rheumatologist. Consecutive patients ≤45 years of age with ≥3 months undiagnosed back pain with any one of psoriasis, acute anterior uveitis (AAU), or colitis diagnosed by the relevant specialist undergo routine clinical evaluation by a rheumatologist for axial SpA. The rheumatologist determines the presence or absence of axial SpA at 3 consecutive stages: 1. After the clinical evaluation; 2. After the results of labs (B27, CRP) and radiography; 3. After the results of MRI evaluation. Final diagnosis by the rheumatologist was used as external standard to test the performance of the algorithms. We tested the following criteria for IBP in the algorithm: ASAS, Berlin, rheumatologist global for likelihood of IBP >5 (0-10 scale), and DUET algorithm in AAU patients.

Results:

A total of 246 patients were recruited, 73 presented with iritis, 46 with psoriasis, and 127 with colitis, 47.6% were diagnosed with axSpA. The diagnosis of axSpA was established in 45.7%, 61.6%, and 40.2% of patients with psoriasis, AAU, and IBD, respectively. The performance of the ASAS-modification of the Berlin algorithm was superior to the original algorithm as reported previously3, primarily for enhanced sensitivity, and this was observed irrespective of the criteria used to define IBP (Table 1). Conversely, the performance of the Duet algorithm in the subset of patients with AAU was substantially worse than previously reported1.

Conclusion:

The ASAS modification of the Berlin algorithm is the preferred referral strategy for patients presenting with undiagnosed back pain to the rheumatologist.

References:

[1]Haroon M, et al. Ann Rheum Dis 2015; 74: 1990-5

[2]Poddubnyy D, et al. J Rheumatol 2011; 38: 2452–60

[3]Van den Berg R, et al. Ann Rheum Dis 2013;72:1646–53

AlgorithmSensitivity (%)Specificity (%)Correct diagnosis (%)False negative (%)False positive (%)Original Berlin(ASAS criteria for IBP)65.376.671.116.712.2Original Berlin(Berlin criteria for IBP)64.476.670.717.112.2Original Berlin(IBP global >5)67.878.173.215.411.4ASAS Modification of Berlin algorithm (ASAS criteria for IBP)73.775.874.812.612.6ASAS Modification of Berlin algorithm (Berlin criteria for IBP)73.775.074.412.613.0ASAS Modification of Berlin algorithm(IBP global >5)76.377.376.811.411.8DUET84.450.071.29.619.2

Disclosure of Interests:

Ulrich Weber: None declared, Georg Kröber: None declared, Raj Carmona: None declared, James Yeung: None declared, Jon Chan: None declared, Sibel Aydin: None declared, Liam Martin: None declared, Ariel Masetto: None declared, Stephanie Keeling: None declared, Olga Ziouzina: None declared, Sherry Rohekar: None declared, Rana Dadashova: None declared, Amanda Carapellucci: None declared, Joel Paschke: None declared, Robert G Lambert: None declared, Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB

FRI0302 WHAT IS THE IMPACT OF DISCREPANCY BETWEEN CENTRAL AND LOCAL READERS IN EVALUATION OF MRI SCANS ON THE CLASSIFICATION OF AXIAL SPONDYLOARTHRITIS? DATA FROM THE ASAS CLASSIFICATION COHORT STUDY

Background:

Active MRI lesions typical of axial spondyloarthritis (axSpA) were reported in 61.6% and 2.2% of axSpA and not-axSpA patients, respectively, from the ASAS classification cohort (ASAS-CC)1. Discrepancy between local and central reader evaluation of MRI scans could result in differences in numbers of patients fulfilling the imaging arm of the ASAS classification criteria. But final classification may not be impacted if discrepant patients still fulfill the clinical arm.

Objectives:

We aimed to assess the impact of reader discrepancy in detection of active MRI lesions on the number of patients classified as having axSpA in patients recruited to the ASAS-CC.

Methods:

MRI images of the sacroiliac joints (SIJs) were available from 252 cases in the ASAS-CC, and these also had clinical and radiographic data. Seven central readers from the ASAS-MRI group recorded MRI lesions in an eCRF that included active lesions typical of axSpA in the SIJ (MRI-active) that was worded exactly the same as in the original ASAS-CC eCRF permitting comparisons between central and local site readers. Active lesions were deemed to be present according to majority agreement (≥4/7) of central readers and also any 2 central readers. We calculated the number of patients that were classified differently after central evaluation for overall fulfilment of the ASAS criteria and for the imaging arm.

Results:

Discordance between central and local readers for detection of MRI-active was recorded in 45(17.8%) and 47(18.2%) of cases according to 2-reader and majority (≥4/7) central reader data, respectively (kappa (95%CI) of 0.64 (0.54-0.73) and 0.62 (0.53-0.72). With central reading as external standard the false-positive rate for active lesions was 26.9%% and 32.2% (‘local overcall’) for 2-reader and majority reader data, respectively. There were 159(63.1%) patients who fulfilled the ASAS axSpA criteria based on local-reading, and 148(58.7%) and 143(56.7%) patients based on 2-reader and majority central-reading, respectively (Table). When fulfillment of the imaging arm was the primary consideration (irrespective of the clinical arm), 126 (50%) patients fulfilled the criteria based on local-reading, and 111 (44%) and 102 (40.5%) patients based on 2-reader and majority central-reading, respectively.

Conclusion:

Despite substantial overcall for positive MRI SIJ inflammation by local readers, the number of patients classified as having axSpA did not change substantially. This is due to the alternate mechanism for classification through the clinical arm.

References:

[1]Rudwaleit et al. Ann Rheum Dis 2009;68: 777-83

Impact of Central Vs. Local Reader SIJ MRI Inflammation Assessment on SpA Classification in cases with all clinical, radiographic, and central and local MRI inflammation data available (n=252)MRI assessment usedSpA Classification = Yes N(%)SpA Classification = No N(%)Imaging Arm SpA Classification = Yes N(%)Imaging Arm SpA Classification = No N(%)Local Reader MRI positive159 (63.1%)93 (36.9%)126 (50%)126 (50%)>2 Central Reader MRI positive148 (58.7%)104 (41.3%)111 (44.0%)141 (56.0%)Majority Central Reader (≥4/7) MRI positive143 (56.7%)109 (43.2%)102 (40.5%)150 (59.5%)

Disclosure of Interests:

Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB, Susanne Juhl Pedersen Grant/research support from: Novartis, Ulrich Weber: None declared, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Joachim Sieper Consultant of: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Speakers bureau: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Stephanie Wichuk: None declared, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Martin Rudwaleit Consultant of: AbbVie, BMS, Celgene, Janssen, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Joel Paschke: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Robert G Lambert: None declared

OP0079 PRELIMINARY DEFINITION OF A POSITIVE MRI FOR STRUCTURAL LESIONS IN THE SACROILIAC JOINTS IN AXIAL SPONDYLOARTHRITIS

Background:

There is lack of international consensus as to what defines a structural lesion on MRI of the sacroiliac joints (SIJ) typical of axial spondyloarthritis (axSpA). The ASAS MRI group has generated updated consensus lesion definitions that describe each of the MRI lesions in the SIJ1. These definitions have been evaluated by 7 readers from the ASAS-MRI group on MRI images from the ASAS Classification Cohort.

Objectives:

We aimed to identify quantitative cut-offs based on numbers of slices and SIJ quadrants that define a positive MRI for structural lesions typical of axSpA, the gold standard being majority central reader decision as to the presence of a structural lesion typical of axSpA with high confidence.

Methods:

MRI structural lesions meeting ASAS definitions were recorded in an eCRF that comprises global assessment (structural lesion typical of axSpA present/absent and degree of confidence (-4 (absent) to +4 (present)), and detailed scoring of lesions per SIJ quadrant. Detailed scoring was based only on assessment of DICOM images (n =148). We calculated sensitivity and specificity for numbers of SIJ quadrants and consecutive slices with erosion, sclerosis, and fat lesions where a majority of readers (≥4/7) agreed as to the presence of a structural lesion typical of axSpA with high confidence (≥ +3). We tested candidate lesion definitions for predictive diagnostic utility in cases assessed after 4.4 years of follow up by the local rheumatologist.

Results:

Structural lesions typical of axSpA were observed by majority read in 33 (32.4%) of 102 cases diagnosed with axSpA, and 3 (6.8%) of 44 cases without axSpA and 29 cases were assigned a high degree of confidence (≥ +3) by a majority of readers. Cut-offs achieving specificity of 95% were erosion in ≥2 consecutive slices (sensitivity 83%), erosion ≥3 SIJ quadrants (sensitivity 90%), and fat lesion (≥1cm horizontal depth) in ≥1 SIJ quadrant (sensitivity 59%) (Table). These had very high positive predictive values (>95%) for diagnosis of axSpA in cases diagnosed by the rheumatologist after 4.4 years follow up.

Conclusion:

ASAS-defined erosion in ≥2 consecutive slices or in ≥3 SIJ quadrants and ASAS-defined fat lesion with depth >1cm in ≥1 SIJ quadrant are high priority candidates for defining an MRI structural lesion typical of axSpA. This will require similar assessment in additional axSpA cohorts.

References:

[1]Maksymowych et al. Ann Rheum Dis 2019; 78:1550-8.

Table 1.

Majority readers agree structural lesion indicative of axSpA is present with confidence ≥3/4 is the gold-standard external reference

SensitivitySpecificityErosion Score ≥1 SIJ qdr93.1 (77.2-99.2)80.6 (72.4-87.3)Erosion Score ≥2 SIJ qdr93.1 (77.2-99.2)90.8 (84.1-95.3)Erosion Score ≥3 SIJ qdr89.7 (72.6-97.8)95.8 (90.5-98.6)Erosion in 2 consecutive slices82.8 (64.2-94.2)95.0 (89.3-98.1)Fat lesion ≥1 SIJ qdr82.8 (64.2-94.2)81.5 (73.4-88.0)Fat lesion ≥2 SIJ qdr69.0 (49.2-84.7)86.6 (79.1-92.1)Fat lesion ≥3 SIJ qdr62.1 (42.3-79.3)91.6 (85.1-95.9)Fat lesion in 2 consecutive slices55.2 (35.7-73.6)93.3 (87.2-97.1)Fat lesion (>1cm depth) ≥158.6 (38.9-76.5)95.0 (89.3-98.1)Fat lesion (>1cm depth) ≥255.2 (35.7-73.6)95.8 (90.5-98.6)Fat lesion (>1cm depth) ≥351.7 (32.5-70.6)97.5 (92.8-99.5)Fat lesion (>1cm depth) in 2 consecutive slices48.3 (29.4-67.5)97.5 (92.8-99.5)

Table. SIJ qdr: sacroiliac joint quadrant

Disclosure of Interests:

Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB, Xenofon Baraliakos: None declared, Ulrich Weber: None declared, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Susanne Juhl Pedersen Grant/research support from: Novartis, Joachim Sieper Consultant of: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Speakers bureau: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Stephanie Wichuk: None declared, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Martin Rudwaleit Consultant of: AbbVie, BMS, Celgene, Janssen, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Joel Paschke: None declared, Robert G Lambert: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB

SAT0384 REPLACEMENT OF RADIOGRAPHIC SACROILITIS BY MRI STRUCTURAL LESIONS: WHAT IS THE IMPACT ON CLASSIFICATION OF AXIAL SPONDYLOARTHRITIS IN THE ASAS CLASSIFICATION COHORT?

Background:

Classification of axial spondyloarthritis (axSpA) is based on either an imaging or clinical arm. Radiographic or MRI evidence of sacroiliitis can be applied for the imaging arm. However, it is well-established that reliability and sensitivity of radiographic sacroiliitis is inadequate.

Objectives:

To assess the impact of replacing radiographic sacroiliitis with MRI structural lesions (MRI-S) typical of axSpA on the number of patients classified as having axSpA in patients with undiagnosed back pain recruited to the ASAS Classification Cohort (ASAS-CC).

Methods:

MRI images of the sacroiliac joint (SIJ) were available from 217 cases in the ASAS-CC, which also had clinical, laboratory, and radiographic data. Seven central readers from the ASAS-MRI group recorded MRI lesions in an eCRF that included active (MRI-A) and structural (MRI-S) lesions typical of axSpA. MRI-A was deemed to be present according to majority agreement (≥4/7) of central readers. MRI-S was deemed to be present according to the majority (majority reader MRI-S) and also according to at least 2 central readers (≥2-reader MRI-S). We calculated the number of patients that were classified differently after replacement of radiographs by MRI-S for overall fulfillment of the ASAS criteria and for the imaging arm.

Results:

In total, 119 (54.8%) cases fulfilled the axSpA criteria based on local reading of radiographic sacroiliitis and central reading of active inflammation on MRI. This changed to 125 (57.6%) and 118 (54.4%) of cases after replacement of radiographic sacroiliitis by ≥2-reader and majority reader MRI-S, respectively (Table). A total of 13 (6.0%) and 7 (3.2%) cases who were classified as not having axSpA were re-classified as having axSpA after replacing radiographic sacroiliitis with ≥2-reader and majority reader MRI-S, respectively. Conversely, 7 (3.2%) and 8 (3.7%) cases were re-classified as not having axSpA after substitution by ≥2-reader and majority reader MRI-S, respectively. When fulfillment of the imaging arm was the primary consideration (irrespective of the clinical arm), the number of patients reclassified from not axSpA to axSpA was 25 (11.5%) by ≥2-reader and 13 (6.0%) by majority reader MRI-S, while 8 (3.7%) and 11 (5.1%) were reclassified from axSpA to not axSpA.

Conclusion:

The number of patients classified as having axSpA does not change substantially when MRI-S replaces radiographic sacroiliitis. However, it remains possible that MRI structural lesions can influence the final diagnosis, the gold standard for assessment of the performance of the ASAS criteria.

Impact of Replacement of Radiographic Sacroilitis by MRI Structural Lesions on SpA Classification in cases with all clinical, radiographic, and central and local MRI inflammation data available (n=217)

MRI assessment usedSpA Classification=Yes N(%)SpA Classification=No N(%)Imaging Arm SpA Classification=Yes N(%)Imaging Arm SpA Classification=No N(%)Radiographic Sacroiliitis + Majority Central Reader MRI Inflammation Positive119 (54.8%)97 (44.7%)83(38.2%)134 (61.8%)Replace Radiographic Sacroiliitis with ≥2 Central Reader MRI Structural Positive125 (57.6%)92 (42.4%)100 (46.1%)117 (53.9%)Replace Radiographic Sacroiliitis with Majority Central Reader MRI Structural Positive118 (54.4%)99 (45.6%)85 (39.2%)132 (60.8%)

Disclosure of Interests:

Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Robert G Lambert: None declared, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Joachim Sieper Consultant of: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Speakers bureau: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Stephanie Wichuk: None declared, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Martin Rudwaleit Consultant of: AbbVie, BMS, Celgene, Janssen, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Joel Paschke: None declared, Susanne Juhl Pedersen Grant/research support from: Novartis, Ulrich Weber: None declared

FRI0317 CONSENSUS DEFINITIONS FOR MRI LESIONS IN THE SPINE OF PATIENTS WITH AXIAL SPONDYLOARTHRITIS: FIRST ANALYSIS FROM THE ASSESSMENTS IN SPONDYLOARTHRITIS INTERNATIONAL SOCIETY CLASSIFICATION COHORT

Background:

A recent consensus from the ASAS MRI group has culminated in updated spine lesion definitions for axial spondyloarthritis (ASAS_MRI_defn)1. There has been no central reader evaluation of MRI scans from the ASAS Classification Cohort (ASAS-CC)2to determine the spectrum of MRI lesions in the spine in this cohort.

Objectives:

To determine the spectrum of active and structural lesions on MRI images of the spine from the ASAS-CC according to the consensus ASAS_MRI_defnupdate.

Methods:

ASAS_MRI_defnwere recorded by 9 central readers in an eCRF for global assessment and detailed scoring of each discovertebral unit and postero-lateral structures. Vertebral corner bone marrow edema (VCBME) and corner fat (VCFAT) lesions were recorded if present on 2 slices; facet joint, lateral, and posterior inflammatory lesions were recorded if present on a single slice. Vertebral corner erosion, bone spurs, and ankylosis were each scored on a single slice. Comparison of active and structural lesion frequencies by local rheumatologist diagnosis of axSpA was assessed descriptively according to ≥2 and majority reader (≥5/9) concordant data.

Results:

MRI scans of the spine were available from 69 cases with axSpA diagnosed in 44/64 (68.8%). VCBME was most frequent with ≥1 lesion in 32(46.4%) and 19 (27.5%) by ≥2 and ≥5/9 readers, respectively. VCFAT was the most frequent structural lesion with ≥1 lesion in 24 (34.8%) and 14 (20.3%) by ≥2 and ≥5/9 readers, respectively. There were significantly more VCBME lesions in axSpA patients than non-axSpA (mean(SD):1.8(2.7) vs 0.3 (0.5)) (p<0.001) while differences in VCFAT were not significant (Table). The presence of ≥2 VCBME had 90-95% specificity for axSpA. Significantly more VCBME and VCFAT were observed in the setting of radiographic sacroiliitis (modified New York criteria (mNY)).

Conclusion:

Spine lesions on MRI are relatively frequent in patients with undiagnosed back pain presenting to the rheumatologist. The presence of ≥2 VCBME, but not VCFAT, may have some diagnostic utility.

References:

[1]Maksymowych WP, et al. Arthritis Rheumatol 70 (suppl 10): 654, 2018

[2]Rudwaleit et al. Ann Rheum Dis 2009;68: 777-83

Vertebral Corner MRI lesionsmajority of readers (>=5)≥2 readersaxSpA=Yes (n=44)axSpA=No (n=20)p-valueaxSpA=Yes (n=44)axSpA=No (n=20)p-valueCorner Fat ≥112 (27.3%)2 (10%)0.1917 (38.6%)7 (35%)0.78Corner Fat ≥210 (22.7%)2 (10%)0.3113 (29.5%)4 (20%)0.64Corner Fat ≥38 (18.2%)1 (5%)0.2510 (22.7%)3 (15%)0.74Corner Fat ≥47 (15.9%)1 (5%)0.429 (20.5%)2 (10%)0.48Corner BME ≥117 (38.6%)1 (5%)0.00625 (54.5%)6 (30%)0.047Corner BME ≥215 (34.1%)1 (5%)0.01319 (43.2%)2 (10%)0.009Corner BME ≥311 (25%)0 (0%)0.01316 (36.4%)1 (5%)0.008Corner BME ≥48 (18.2%)0 (0%)0.09412 (27.3%)1 (5%)0.048mNY=Yes (n=10)mNY=No (n=49)p-valuemNY=Yes (n=10)mNY=No (n=49)p-valueCorner Fat ≥15 (50%)9 (18.4%)0.0475 (50%)17 (34.7%)0.48Corner Fat ≥25 (50%)7 (14.3%)0.0225 (50%)11 (22.4%)0.12Corner Fat ≥34 (40%)5 (10.2%)0.0364 (40%)9 (18.4%)0.20Corner Fat ≥44 (40%)4 (8.2%)0.0224 (40%)7 (14.3%)0.079Corner BME ≥15 (50%)11 (22.4%)0.1167 (70%)22 (44.9%)0.18Corner BME ≥25 (50%)9 (18.4%)0.0475 (50%)14 (28.6%)0.27Corner BME ≥35 (50%)6 (12.2%)0.0145 (50%)11 (22.4%)0.12Corner BME ≥45 (50%)3 (6.1%)0.0025 (50%)7 (14.3%)0.022

Disclosure of Interests:

Walter P. Maksymowych Grant/research support from: AbbVie, Novartis, Pfizer, and UCB, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Employee of: Chief Medical Officer of CARE Arthritis Limited, Speakers bureau: AbbVie, Janssen, Novartis, Pfizer, and UCB, Iris Eshed: None declared, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Susanne Juhl Pedersen Grant/research support from: Novartis, Ulrich Weber: None declared, Manouk de Hooge: None declared, Joachim Sieper Consultant of: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Speakers bureau: AbbVie, Boehringer Ingelheim, Eli Lilly and Company, Janssen, Merck, Novartis, Pfizer, Roche, and UCB Pharma, Stephanie Wichuk: None declared, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Martin Rudwaleit Consultant of: AbbVie, BMS, Celgene, Janssen, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Robert G Lambert: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

SAT0548 DEVELOPMENT AND VALIDATION OF THREE PRELIMINARY MRI SACROILIAC JOINT COMPOSITE STRUCTURAL DAMAGE SCORES IN A 5-YEAR LONGITUDINAL STUDY OF PATIENTS WITH AXIAL SPONDYLOARTHRITIS

Background:

In axial spondyloarthritis (axSpA), MRI reliably detects structural lesions in the sacroiliac joints (SIJs). The SPARCC SIJ Structural Score (SSS)(1) is a reliable and validated method to assess the individual structural lesions of the SIJs, i.e. fat lesion, erosion, backfill (fat metaplasia in an erosion cavity) and ankylosis. Several MRI studies have indicated that bone destruction, i.e. erosion, is often followed by formation of new bone in the erosion cavity (backfill), ultimately leading to ankylosis(2).

Objectives:

The aim was to combine SPARCC SSS for erosion, backfill and ankylosis into a composite score for SIJ structural damage and to test this score in a 5-year follow up study.

Methods:

Thirty-three patients fulfilling ASAS criteria for axSpA were followed for 5 years after initiation of TNF inhibitor in the BIOSPA study(3). T1-weighted and STIR MRI sequences of the SIJs acquired at week 0, 46 and year 2, 3, 4, 5 were evaluated with SPARCC SSS. In each of 5 slices of each SIJ, erosion is scored 0-1 per joint quadrant (score range 0-40), backfill 0-1 per joint half (score range 0-20) and ankylosis 0-1 per joint half (score range 0-20). Based on the scores for erosion, backfill and ankylosis 3 versions of a preliminary Composite axSpA MRI SIJ Structural Damage Score (CSDS) were calculated:

CSDS–A: (erosion score x0.5) + backfill score + ankylosis score

CSDS–B: (erosion score x1) + (backfill score x4) + (ankylosis score x6)

CSDS–C: (erosion score x1) < (backfill score x4) < (ankylosis score x6)

The “<” indicates a hierarchical order, meaning that erosion was not scored if backfill was present in the same joint half and erosion and backfill were not scored if ankylosis was present in the joint half.

Results:

Patients were divided into two groups: patients with almost complete bilateral ankylosis (baseline SPARCC SSS Ankylosis ≥18, n=10) and patients with no/minor ankylosis (baseline SPARCC SSS Ankylosis ≤7, n=23). At baseline patients with no/minor ankylosis were younger, had shorter symptom duration, lower BASMI, higher SPARCC SIJ Inflammation, lower SSS Fat, Erosion, Backfill and Ankylosis, as compared with patients with almost complete ankylosis.

At baseline, CSDS-A, -B and -C correlated positively with SPARCC SSS Fat and Ankylosis and modified New York criteria grading, and negatively with BASDAI and SPARCC inflammation. Change in CSDS-B and -C over 5 years correlated positively with change in SSS Fat and Ankylosis and negatively with change in SPARCC Inflammation. There was no change in the group with almost complete ankylosis.

The annual progression for CSDS-B and -C was statistically significantly larger in year 1 compared with year 4 (p=0.01) and numerically larger compared with year 2 (p=0.075), 3 (p=0.382) and 5 (p=0.073). Figure 1 shows the annual change in patients with no/minor ankylosis.

Conclusion:

Three preliminary Composite Structural Damage Scores for MRI assessment of the SIJs in patients with axSpA, which allows scoring of MRI progression of erosion through backfill to ankylosis, were introduced. Progression was most pronounced the first year after TNF inhibitor initiation. This novel approach may be useful for monitoring structural progression in axSpA. We suggest that these methods are further tested for responsiveness and ability to differentiate between different therapies in randomized controlled trials.

References:

[1]Maksymowych WP et al. J Rheum 2015;42:79-86.

[2]Maksymowych WP et al. Art Rheum 2014;66:2958-67.

[3]Pedersen SJ et al. Scand J Rheum 2019;48:185-197.

Disclosure of Interests:

Marie Wetterslev: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Inge Juul Sørensen: None declared, Ulrich Weber: None declared, Anne Gitte Loft Grant/research support from: Novartis, Consultant of: AbbVie, MSD, Novartis, Pfizer and UCB, Speakers bureau: AbbVie, MSD, Novartis, Pfizer and UCB, Gina Kollerup Speakers bureau: Eli Lilly, Lars Juul: None declared, Gorm Thamsborg: None declared, Ole Madsen: None declared, Jakob Møllenbach Møller: None declared, Susanne Juhl Pedersen Grant/research support from: Novartis

Direct and seasonal legacy effects of the 2018 heat wave and drought on European ecosystem productivity

In summer 2018, central and northern Europe were stricken by extreme drought and heat (DH2018). The DH2018 differed from previous events in being preceded by extreme spring warming and brightening, but moderate rainfall deficits, yet registering the fastest transition between wet winter conditions and extreme summer drought. Using 11 vegetation models, we show that spring conditions promoted increased vegetation growth, which, in turn, contributed to fast soil moisture depletion, amplifying the summer drought. We find regional asymmetries in summer ecosystem carbon fluxes: increased (reduced) sink in the northern (southern) areas affected by drought. These asymmetries can be explained by distinct legacy effects of spring growth and of water-use efficiency dynamics mediated by vegetation composition, rather than by distinct ecosystem responses to summer heat/drought. The asymmetries in carbon and water exchanges during spring and summer 2018 suggest that future land-management strategies could influence patterns of summer heat waves and droughts under long-term warming.

Scoring magnetic resonance imaging (MRI) inflammation and structural lesions in sacroiliac joints of patients with axial spondyloarthritis: assessment of all MRI slices of the cartilaginous compartment versus standardized six or five slices

Objectives: The Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint (SIJ) scoring system assesses six or five (6/5) semicoronal magnetic resonance imaging (MRI) slices for inflammation/structural lesions in patients with axial spondyloarthritis (axSpA). However, the cartilaginous SIJ compartment may be visible in a few additional slices. The objective was to investigate interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types using an 'all slices' approach versus standard SPARCC scoring of 6/5 slices.Method: Fifty-three axSpA patients were treated with the tumour necrosis factor inhibitor golimumab and followed with serial MRI scans at weeks 0, 4, 16, and 52. The most anterior and posterior slices covering the cartilaginous compartment and the transitional slice were identified. Scores for inflammation, fat metaplasia, erosion, backfill, and ankylosis in the cartilaginous SIJ compartment were calculated for the 'all slices' approach and the 6/5 slices standard.Results: By the 'all slices' approach, three readers scored mean 7.2, 7.7, and 7.0 slices per MRI scan. Baseline and change scores for the various lesion types closely correlated between the two approaches (Pearson's rho ≥ 0.95). Inflammation score was median 13 (interquartile range 6-21, range 0-49) for 6/5 slices versus 14 (interquartile range 6-23, range 0-69) for all slices at baseline. Interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types were similar.Conclusion: The standardized 6/5 slices approach showed no relevant differences from the 'all slices' approach and, therefore, is equally suited for monitoring purposes.

Research plans in Europe for radiation health hazard assessment in exploratory space missions

The European Space Agency (ESA) is currently expanding its efforts in identifying requirements and promoting research towards optimizing radiation protection of astronauts. Space agencies use common limits for tissue (deterministic) effects on the International Space Station. However, the agencies have in place different career radiation exposure limits (for stochastic effects) for astronauts in low-Earth orbit missions. Moreover, no specific limits for interplanetary missions are issued. Harmonization of risk models and dose limits for exploratory-class missions are now operational priorities, in view of the short-term plans for international exploratory-class human missions. The purpose of this paper is to report on the activity of the ESA Topical Team on space radiation research, whose task was to identify the most pertinent research requirements for improved space radiation protection and to develop a European space radiation risk model, to contribute to the efforts to reach international consensus on dose limits for deep space. The Topical Team recommended ESA to promote the development of a space radiation risk model based on European-specific expertise in: transport codes, radiobiological modelling, risk assessment, and uncertainty analysis. The model should provide cancer and non-cancer radiation risks for crews implementing exploratory missions. ESA should then support the International Commission on Radiological Protection to harmonize international models and dose limits in deep space, and guarantee continuous support in Europe for accelerator-based research configured to improve the models and develop risk mitigation strategies.

Structural progression rate decreases over time on serial radiography and magnetic resonance imaging of sacroiliac joints and spine in a five-year follow-up study of patients with ankylosing spondylitis treated with tumour necrosis factor inhibitor

OBJECTIVE

To investigate temporal changes in structural progression assessed by serial conventional radiography and magnetic resonance imaging (MRI) of the sacroiliac joints (SIJs) and spine in patients with ankylosing spondylitis (AS) treated with tumour necrosis factor (TNF) inhibitor for 5 years.

METHOD

Forty-two patients were included and 33 patients were followed for 5 years in a prospective investigator-initiated study. Conventional radiographs were required four times and MRI seven times. The modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS); Spondyloarthritis Research Consortium of Canada (SPARCC) MRI SIJ and Spine Inflammation, and SPARCC MRI SIJ Structural Score (SSS) for Fat, Erosion, Backfill, and Ankylosis; and the Canada-Denmark MRI scores for Spine Inflammation, Fat, Erosion, and New Bone Formation (NBF) were applied.

RESULTS

Compared with baseline, MRI Inflammation had decreased significantly at week 22 (spine)/week 46 (SIJ) and thereafter. MRI SIJ Fat (from week 22), SIJ Ankylosis, Spine NBF, and mSASSS had increased significantly at week 46 and thereafter. SIJ Erosion had decreased from year 2. The annual progression rate in mSASSS was significantly higher during weeks 0-46 compared to week 46 to year 3. In multivariate regression analyses, baseline SIJ Inflammation and Backfill were independent predictors of 5 year progression in SIJ Ankylosis. Spine Erosion predicted progression in Spine NBF. Longitudinally, Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Disease Activity Index, MRI Spine Inflammation, Fat, and Erosion scores were significantly associated with mSASSS. SIJ Inflammation, Fat, Erosion, and Backfill scores were longitudinally associated with SIJ Ankylosis. Structural progression was not associated with body mass index, smoking, or Assessment of SpondyloArthritis international Society Non-Steroidal Anti-Inflammatory Drug Index.

CONCLUSION

In a 5 year follow-up study of patients with AS treated with TNF inhibitor, structural progression decreased over time.

Biokompatibilitätsprobleme bei der Hämodialyse

Seit erstmals Interaktionen von Blut und körperfremden Materialien bei der chronischen Hämodialysebehandlung beobachtet wurden, folgten zahlreiche Untersuchungen, um das Phänomen der Biokompatibilität zu ergründen. Dies hatte zur Folge, daß erhebliche Verbesserungen bei den Membranen, Schlauchsystemen, Geräten und der Behandlung selbst erzielt werden konnten. Im folgenden wird versucht, einen Überblick über die auslösenden Ursachen und die Phänomene, die durch die Interaktion von Blut mit körperfremden Oberflächen verursacht werden, aufzuzeigen.

Die Probleme, die bei der Entwicklung biokompatibler Membranen vorhanden sind, scheinen in naher Zukunft noch nicht alle lösbar zu sein. Unsere ganze Sorgfalt muß daher der Hämodialysebehandlung selbst und der Verringerung ihrer möglichen Nebenwirkungen, die z.B. durch Reste von Sterilisationsmitteln, endotoxinhaltige Dialysierflüssigkeiten hervorgerufen werden können, gelten. Besonders im Hinblick darauf, daß die Zahl der Patienten, die Biomaterialien benötigen, rasch zunimmt und diese Patienten länger leben, wodurch sie den Gefahren durch die Biounverträglichkeit der Materialien länger ausgesetzt werden, sind wir alle aufgefordert, unseren Patienten eine risikoarme Hämodialyse zu ermöglichen served in the treatment of chronic hemodialysis, numerous investigations were performed to definite the phenomena of biocompatibility. As a consequence, considerable improvements in membranes, tube systems, equipments and in the treatment itself have been accomplished. The following is an attempt to demonstrate the initiating causes and the phenomena which results from the interaction of blood with artificial surfaces.

The problems being encountered in the development of biocompatible membranes are not likely to all be solved in the near future. We must, therefore, concentrate all our efforts on the hemodialysis treatment itself and on the reduction of its possible side-effects which can, for example, be caused by the remnants of sterilizing agents, dialysis fluid containing endotoxin, etc. Especially in view of the fact that the number of patients requiring biomaterials is rapidly increasing and that these patients are living longer, whereby they are exposed to the dangers of bioincompatibility of the materials for a longer period of time, we are all called upon to provide low-risk hemodialysis for our patients.

Measuring impairments of functioning and health in patients with axial spondyloarthritis by using the ASAS Health Index and the Environmental Item Set: translation and cross-cultural adaptation into 15 languages

Introduction

The Assessments of SpondyloArthritis international society Health Index (ASAS HI) measures functioning and health in patients with spondyloarthritis (SpA) across 17 aspects of health and 9 environmental factors (EF). The objective was to translate and adapt the original English version of the ASAS HI, including the EF Item Set, cross-culturally into 15 languages.

Methods

Translation and cross-cultural adaptation has been carried out following the forward–backward procedure. In the cognitive debriefing, 10 patients/country across a broad spectrum of sociodemographic background, were included.

Results

The ASAS HI and the EF Item Set were translated into Arabic, Chinese, Croatian, Dutch, French, German, Greek, Hungarian, Italian, Korean, Portuguese, Russian, Spanish, Thai and Turkish. Some difficulties were experienced with translation of the contextual factors indicating that these concepts may be more culturally-dependent. A total of 215 patients with axial SpA across 23 countries (62.3% men, mean (SD) age 42.4 (13.9) years) participated in the field test. Cognitive debriefing showed that items of the ASAS HI and EF Item Set are clear, relevant and comprehensive. All versions were accepted with minor modifications with respect to item wording and response option. The wording of three items had to be adapted to improve clarity. As a result of cognitive debriefing, a new response option ‘not applicable’ was added to two items of the ASAS HI to improve appropriateness.

Discussion

This study showed that the items of the ASAS HI including the EFs were readily adaptable throughout all countries, indicating that the concepts covered were comprehensive, clear and meaningful in different cultures.

[Adherence to Phase III Cardiac Rehabilitation Programs: A Prospective, Randomized Comparison between a Conventionally Conducted Program and a Tai Chi-Based Program]

INTRODUCTION

In patients with cardiac diseases, lifestyle changes such as an increase in physical activity are recommended to prevent further cardiac events. In Germany this is possible by attending outpatient heart groups. A problem inherent in these programs is the lack of adherence since more than two thirds of patients stop attending cardiac rehabilitation programs after six months. An alternative to the conventional implementation of heart groups is Tai Chi, which was found to improve adherence to cardiac rehabilitation programs in international studies.

METHODS

Patients were randomly assigned to a conventional heart group or a heart group with Tai Chi exercises. At the beginning of the study, a medical history was taken and physical and instrumental tests were carried out, including an assessment of anxiety/depression (HADS questionnaire) and physical well-being (SD-12). Follow-up tests were performed every three months.

RESULTS

Patients were 62.6 ± 8.5 years old, the mean BMI was 28.6 ± 62 kg/m(2), and the proportion of women was 29.8 %. The groups were different in terms of age (conventional heart group: 65.0 ± 7.5; Tai Chi group: 59.9 ± 8.9 years). Therefore, age-adjusted analyses were performed in addition to the planned analyses. Regarding the primary endpoint of the study, there was no difference between the groups. After twelve months, 50 % of subjects were active in the Tai Chi group and 48 % in the conventional heart group (odds ratio 0.92, p = 0.891). After adjustment for age by logistic regression, the odds ratio was 0.47 (p = 0.285). Furthermore, both the participation period in weeks (Tai Chi group: 43.3 ± 26.0; conventional group: 45.5 ± 24.2, p = 0.766) and the participation rate (Tai Chi group: 66.8 ± 19.2 % Tai Chi, conventional group: 76.3 ± 16.5 %, p = 0.074) did not differ between the two groups. A further analysis showed a non-significant trend for improvement of anxiety, depression and physical well-being in the Tai Chi group compared with the conventional group.

CONCLUSION

The insight gained in international studies regarding a better adherence to Tai Chi-guided prevention programs was not transferable to heart group participants from Germany. However, there was a trend regarding a better mental condition in the Tai Chi group.

A pilot study of the relationship between Doppler-estimated carotid and brachial artery flow and cardiac index

We measured carotid and brachial artery blood flow by Doppler ultrasound in 11 human volunteers, and related these to cardiac index and to each other. The median (IQR [range]) carotid arterial blood flow was 0.334 (0.223-0.381 [0.052-0.563]) l.min(-1) on the right and 0.315 (0.223-0.369 [0.061-0.690]) l.min(-1) on the left. The brachial arterial blood flow was 0.049 (0.033-0.062 [0.015-0.204]) l.min(-1) on the right and 0.039 (0.027-0.054 [0.011-0.116]) on the left. Cardiac index was 3.2 (2.8-3.5 [1.9-5.4]) l.min(-1) .m(-2) . There was a moderate to good correlation between right-and left-sided flows (brachial: ρ = 0.45; carotid: ρ = 0.567). Brachial and carotid flow had no or a negative correlation with cardiac index (right brachial: ρ = -0.145, left brachial: ρ = -0.349; right carotid: ρ = -0.376, left carotid: ρ = -0.285). In contrast to some previous studies, we found that Doppler-estimated peripheral arterial blood flows only show a weak correlation with cardiac index and cannot be used to provide non-invasive estimates of cardiac index in man.