Low incidence of malignancy in patients with suspected polymyalgia rheumatica or giant cell arteritis, examined with FDG-PET/CT

Introduction

The need to systematically examine patients suspected of polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) for malignancy is controversial. The aim of this study was to assess the frequency of malignancy in patients with suspected PMR and/or GCA who have been referred to a 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography with computed tomography (FDG-PET/CT) as part of the diagnostic investigation.

Method

The records of all patients referred to FDG-PET/CT from Center for Rheumatology and Spine Diseases, Rigshospitalet, Glostrup with the suspicion of PMR and/or GCA during a two-year period, were retrospectively reviewed. Data was analyzed with descriptive statistics, and a standard incidence ratio was calculated based on background cancer incidences extracted from the NORDCAN database.

Results

220 patients were included in the study. Findings suspicious of malignancy were found in 19 of the examinations, and in seven cases (3.2%), malignancy was confirmed. In three out of the seven cases the patients were diagnosed with PMR concomitantly with malignancy. The estimated standardized incidence ratio (SIR) for cancer compared to the background incidence of cancer in Denmark was 1.58 (95% CI 0.63-2.97), i.e., not statistically significant. There were no statistically significant differences in characteristics of the patients that were diagnosed with malignancy compared with those that were not.

Conclusion

The frequency of malignancy in this cohort of patients with suspected PMR/GCA who underwent PET/CT was low. Our results, though based on a small cohort, do not suggest that all patients with suspected PMR/GCA should systematically be examined with FDG-PET/CT for excluding malignancy.

Peripheral joint and enthesis involvement in patients with newly diagnosed inflammatory bowel disease: symptoms, clinical and ultrasound findings - a population-based cohort study

OBJECTIVES

Musculoskeletal manifestations in patients with inflammatory bowel disease (IBD) are common and associated with poorer outcomes. Hence, early detection is important to optimally tailor treatment. We aimed to determine the prevalence and distribution of inflammatory lesions in peripheral joints and entheses in newly diagnosed IBD patients.

DESIGN

Patients with newly diagnosed IBD from a prospective population-based inception cohort were consecutively included. Data on musculoskeletal symptoms were collected by questionnaires and by structured rheumatological interview. Peripheral joints and entheses were assessed clinically and by ultrasound (US), using standardized definitions.

RESULTS

Of 110 included patients (mean age: 42 years, 40% male, 70 with ulcerative colitis (UC), 40 with Crohn's disease (CD)), history of ≥1 musculoskeletal symptoms was reported by 49%. Clinical examination revealed peripheral musculoskeletal manifestations in 56 (52.3%) patients; 29 (27.1%) had ≥1 tender and/or swollen joints and 49 (45.8%) ≥1 tender entheses. Small peripheral joints were predominantly affected. US found inflammation in ≥1 joint or enthesis in 52 (49.5 %) patients; 29 (27.4 %) had US synovitis in ≥1 joint, while 36 (34%) US enthesitis. Fibromyalgia classification criteria were fulfilled in seven (7.9%) patients. There was no difference in clinical or US findings between patients with UC and CD, nor between patients with active and inactive IBD.

CONCLUSION

Half of patients with newly diagnosed IBD had inflammation in their peripheral joints and/or entheses, documented by rheumatological clinical and ultrasound evaluations. This indicates a need for multidisciplinary collaboration to ensure an optimal therapeutic strategy for suppressing inflammation in all disease domains.

Multimodality Imaging in Cranial Giant Cell Arteritis: First Experience with High-Resolution T1-Weighted 3D Black Blood without Contrast Enhancement Magnetic Resonance Imaging

In order to support or refute the clinical suspicion of cranial giant cell arteritis (GCA), a supplemental imaging modality is often required. High-resolution black blood Magnetic Resonance Imaging (BB MRI) techniques with contrast enhancement can visualize artery wall inflammation in GCA. We compared findings on BB MRI without contrast enhancement with findings on 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/low-dose computed tomography (2-[18F]FDG PET/CT) in ten patients suspected of having GCA and in five control subjects who had a 2-[18F]FDG PET/CT performed as a routine control for malignant melanoma. BB MRI was consistent with 2-[18F]FDG PET/CT in 10 out of 10 cases in the group with suspected GCA. In four out of five cases in the control group, the BB MRI was consistent with 2-[18F]FDG PET/CT. In this small population, BB MRI without contrast enhancement shows promising performance in the diagnosis of GCA, and might be an applicable imaging modality in patients.

The provisional OMERACT ultrasonography score for giant cell arteritis

OBJECTIVES

To develop an Outcome Measures in Rheumatology (OMERACT) ultrasonography score for monitoring disease activity in giant cell arteritis (GCA) and evaluate its metric properties.

METHODS

The OMERACT Instrument Selection Algorithm was followed. Forty-nine members of the OMERACT ultrasonography large vessel vasculitis working group were invited to seven Delphi rounds. An online reliability exercise was conducted using images of bilateral common temporal arteries, parietal and frontal branches as well as axillary arteries from 16 patients with GCA and 7 controls. Sensitivity to change and convergent construct validity were tested using data from a prospective cohort of patients with new GCA in which ultrasound-based intima-media thickness (IMT) measurements were conducted at weeks 1, 3, 6, 12 and 24.

RESULTS

Agreement was obtained (92.7%) for the OMERACT GCA Ultrasonography Score (OGUS), calculated as follows: sum of IMT measured in every segment divided by the rounded cut-off values of IMTs in each segment. The resulting value is then divided by the number of segments available. Thirty-five members conducted the reliability exercise, the interrater intraclass correlation coefficient (ICC) for the OGUS was 0.72-0.84 and the median intrareader ICC was 0.91. The prospective cohort consisted of 52 patients. Sensitivity to change between baseline and each follow-up visit up to week 24 yielded standardised mean differences from -1.19 to -2.16, corresponding to large and very large magnitudes of change, respectively. OGUS correlated moderately with erythrocyte sedimentation rate, C reactive protein and Birmingham Vasculitis Activity Score (corrcoeff 0.37-0.48).

CONCLUSION

We developed a provisional OGUS for potential use in clinical trials.

Comparison of temporal artery ultrasound versus biopsy in the diagnosis of giant cell arteritis

BACKGROUND/OBJECTIVES

Giant cell arteritis (GCA) is a medical and ophthalmological emergency due to risk of stroke and sudden irreversible loss of vision. Fast and accurate diagnosis is important to prevent complications and long-term high dose glucocorticoids toxicity. Temporal artery biopsy is gold standard for diagnosing GCA. However, temporal artery ultrasound is a fast and non-invasive procedure which may provide a supplement or an alternative to biopsy. This study assesses the diagnostic performance of ultrasound and biopsy in the diagnosis of GCA.

SUBJECTS/METHODS

Examination results of patients suspected of having GCA in the period from August 2018 to June 2019 were reviewed. Patients underwent clinical examination and blood tests. Within a few days of starting glucocorticoid treatment, temporal ultrasound and unilateral biopsy were performed. Experienced physicians established the final clinical diagnosis at 6-months follow-up.

RESULTS

Seventy-eight patients underwent both ultrasound and biopsy. Thirty-five (45%) received the final clinical diagnosis of GCA. Compared with the final clinical diagnosis, biopsy had a sensitivity of 69% (51-83%) and a specificity of 100% (92-100%), and ultrasound a sensitivity of 63% (45-79%) and a specificity of 79% (64-94%). Area under the receiver operating characteristics curves were 0.84 and 0.71 for biopsy and ultrasound respectively (p = 0.048). False negative rate of ultrasound was 4 out of 78 (5%).

CONCLUSION

Sensitivity of ultrasound is almost on par with that of biopsy although the overall diagnostic accuracy of ultrasound was slightly lower. We find that ultrasound is a reliable tool for first line diagnosis of GCA.

Diagnostic accuracy of vascular ultrasound in patients with suspected giant cell arteritis (EUREKA): a prospective, multicentre, non-interventional, cohort study

BACKGROUND

Temporal artery biopsy is considered the diagnostic gold standard for giant cell arteritis, despite approximately 39% of patients who are negative for the condition by biopsy subsequently being given a clinical diagnosis of giant cell arteritis. We aimed to assess the diagnostic accuracy of ultrasound examination in patients with suspected giant cell arteritis.

METHODS

In this prospective, multicentre, non-interventional, cohort study (evaluation of ultrasound's role in patients suspected of having extracranial and cranial giant cell arteritis; EUREKA), we consecutively recruited patients aged 50 years or older, with clinically suspected giant cell arteritis from three Danish hospitals (South West Jutland Hospital in Esbjerg, Silkeborg Regional Hospital, and Rigshospitalet, Glostrup). Participants had a bilateral ultrasound of the temporal, facial, common carotid, and axillary arteries. Ultrasounds were done by ultrasonographers who were systematically trained in vascular ultrasound using appropriate equipment and settings. Participants then had a temporal artery biopsy within 7 days of initiation of corticosteroid treatment. A blinded ultrasound expert assessed all ultrasound images. Ultrasound vasculitis was defined in cranial arteries as a homogeneous, hypoechoic, intimamedia complex thickness and a positive compression sign and as a homogeneous intimamedia complex of 1 mm in thickness or wider in the axillary arteries and of 1·5 mm thickness or wider in the common carotid artery. Participants were followed up at 6 months. During this 6 month period, clinicians were able to collect data from all clinical examinations to enable a full clinical diagnosis at 6 months. Clinical diagnosis was based on the expert opinion of the treating rheumatologist. The diagnostic criterion standard was diagnosis confirmed after 6 months of follow-up. We used logistic regression analyses to calculate the odds ratio and 95% CI of ultrasound as a predictor for giant cell arteritis.

FINDINGS

Between April 1, 2014, and July 31, 2017, 118 patients were screened for inclusion, of whom 106 had both ultrasound examinations and an eligible temporal artery biopsy and were included in the intention-to-diagnose population. The mean age was 72·7 years (SD 7·9), 63 (59%) participants were women, and 43 (41%) were men. Temporal artery biopsy was positive in 46 (43%) of 106 patients, and 62 (58%) of 106 patients had a clinically confirmed diagnosis of giant cell arteritis at 6 months (temporal artery biopsy sensitivity 74% [95% CI 62-84], specificity 100% [95% CI 92-100]). Cranial artery ultrasound was positive in all patients who had a positive temporal artery biopsy, and seven (58%) of 12 patients who were positive by ultrasound and negative by temporal artery biopsy were confirmed to have large-vessel giant cell arteritis via other imaging methods. The sensitivity of ultrasound diagnosis of giant cell arteritis was 94% (84-98) and specificity was 84% (70-93). Logistic regression analysis confirmed that ultrasound was the strongest baseline predictor for a clinically confirmed diagnosis of giant cell arteritis at 6 months (crude odds ratio 76·6 [95% CI 21·0-280·0]; adjusted for sex and age 141·0 [27·0-743·0]).

INTERPRETATION

Vascular ultrasound might effectively replace temporal artery biopsy as a first-line diagnostic method in patients suspected of having giant cell arteritis when done by systematically trained ultrasonographers using appropriate equipment and settings.

FUNDING

The Institute for Regional Research at Hospital of Southwest Jutland, Esbjerg, Denmark.

Vascular ultrasound for the diagnosis of giant cell arteritis: a reliability and agreement study based on a standardised training programme

Objective

To evaluate the impact of a standardised training programme including equipment adjustment for experienced musculoskeletal ultrasonographers without previous experience in vascular ultrasound (US) on the reliability of US in the diagnosis of giant cell arteritis (GCA).

Methods

In this prospective, non-interventional observational cohort study, patients suspected of GCA were evaluated by US by one of five rheumatologists with long-standing experience in musculoskeletal US (>8 years), trained using a standardised training programme including equipment adjustment. Images of cranial and large vessels were subsequently evaluated first by the performing ultrasonographer and thereafter by a blinded external expert (gold standard).

Results

In three Danish centres, 112 patients suspected of GCA were included. According to the external expert, vasculitis changes were seen in 66 patients, in 45 of them with only cranial involvement, in 14 with both cranial and large vessel involvement, while in seven patients isolated large vessel vasculitis was found. The reliability was excellent between the local ultrasonographer and the US expert for the overall GCA diagnosis regarding the diagnosis of cranial and for large vessel GCA, with an interobserver agreement of 95–96%, mean kappa values of 0.88–0.92 (95% CI 0.78 to 0.99). Excellent reliability (mean kappa 0.86–1.00) was also found for the US examination of the individual arteries (temporal, facial, common carotid and axillary).

Conclusion

The US training programme resulted in excellent agreement between trainees and an expert in patients suspected of GCA and may thus be applicable for implementation of vascular US in clinical practice.

Ultrasound assessment of hands and feet for synovitis at time of first clinical visit markedly reduces time to diagnosis in routine care

OBJECTIVES

The role of musculoskeletal ultrasound (MSUS) in routine care for diagnosing arthritis is not fully elucidated, but US is more sensitive than clinical joint examination for detecting synovitis. Therefore, the use of US may facilitate diagnosis of arthritis. The aim of the study was to assess if MSUS examination of hands and feet in relation to the first clinical visit had an impact on the time to reach a final diagnosis and the number of clinical follow-up visits needed after first consultation.

METHODS

Two cohorts referred to the outpatient arthritis clinic with suspected arthritis were compared with each other, 1. MSUS (October 2017 to June 2018) of hands and feet performed prior to the first clinical visit and 2. MSUS (November 2016 to June 2017) was performed Ad hoc, for following aspects: time to clinical diagnosis, number of clinical visits needed, and number of ultrasound examinations.

RESULTS

In total, 163 and 109 patients were included in the MSUS and comparative cohorts, respectively. Adding MSUS to the first clinical visit reduced the time to diagnosis from mean 31(SD ± 32.2) days to 12(±17.3) days(p< 0.01). The number of clinical visits needed was reduced from mean 2.8(±1.1)-2.1(±1.3),(p< 0.01) corresponding to a reduction of 114 visits in the MSUS cohort. A final diagnosis with inflammatory arthritis was found in 76(47%) of patients in the MSUS cohort vs 29(27%) in the comparative cohort(p< 0.01).

CONCLUSION

In patients referred for suspected arthritis, routine MSUS in relation to the first clinical visit significantly reduces time to diagnosis and number of clinical visits needed to reach a final diagnosis.

Seasonal variation in biopsy-proven giant cell arteritis in Eastern Denmark from 1990-2018

PURPOSE

The purpose of this study was to investigate seasonal variation in cases of biopsy-proven GCA in eastern Denmark in a 29-year period.

METHODS

Pathology records of all temporal artery biopsies in eastern Denmark between 1990 and 2018 were reviewed. For each patient, data were collected which included age, sex, date of birth and biopsy result. Seasonality was evaluated using logistic regression and Poisson regression analysis. Lastly, an explorative pilot study was conducted to investigate a possible association between three weather parameters (average temperature, amount of rain and hours of sunshine) and the biopsy outcome.

RESULTS

One thousand three hundred twenty-three biopsies were included of which 336 fulfilled objective criteria for GCA diagnosis. Mean age at diagnosis was 75.6 years (range 52-94 years). Among the biopsy-proven cases of GCA, there were 223 women (66.3%, mean age 76.2 years) and 113 men (33.7%, mean age 74.4 years) giving a female to male ratio of 1.97:1. The peak occurrence of GCA was in the 70-79 years age group. Statistical analysis of seasonal variation showed an increased risk of a positive biopsy during summer compared to autumn (p = 0.037). No association between the three weather parameters and the biopsy outcome was found.

CONCLUSION

In this study of biopsy-proven GCA in a large Danish patient cohort, the occurrence of GCA showed seasonal variation with higher occurrence in the summer months when compared to autumn. Future studies pooling all cases of GCA worldwide are needed to determine seasonality in the occurrence of GCA.

OMERACT definition and reliability assessment of chronic ultrasound lesions of the axillary artery in giant cell arteritis

OBJECTIVES

To define chronic ultrasound lesions of the axillary artery (AA) in long-standing giant cell arteritis (GCA) and to evaluate the reliability of the new ultrasound definition in a web-based exercise.

METHODS

A structured Delphi, involving an expert panel of the Large Vessel Vasculitis subgroup of the Outcome Measures in Rheumatology (OMERACT) Ultrasound Working Group was carried out. The reliability of the new definition was tested in a 2-round web-based exercise involving 23 experts and using 50 still images each from AA of long-standing and acute GCA patients, as well as 50 images from healthy individuals.

RESULTS

The final OMERACT ultrasound definition of chronic changes was based on measurement and appearance of the intima-media complex. The overall reliability of the new definition for chronic ultrasound changes in longstanding GCA of the AA was good to excellent with Light's kappa values of 0.79-0.80 for inter-reader reliability and mean Light's-kappa of 0.88 for intra-reader reliability. The mean inter-rater and intra-rater agreements were 86-87% and 92%, respectively. Good reliabilities were observed comparing the vessels with longstanding versus acute GCA with a mean agreement and kappa values of 81% and 0.63, respectively.

CONCLUSION

The new OMERACT ultrasound definition for chronic vasculitis of the AA in GCA revealed a good to excellent inter- and intra-reader reliability in a web-based exercise of experts.

Doppler ultrasound predicts successful discontinuation of biological DMARDs in rheumatoid arthritis patients in clinical remission

OBJECTIVE

To assess the ability of ultrasound to predict successful tapering and successful discontinuation of biological disease-modifying anti-rheumatic drugs (bDMARDs) at 2-year follow-up in rheumatoid arthritis (RA) patients in sustained remission.

METHODS

Patients in sustained remission (DAS28-CRP≤2.6) and no radiographic progression the previous year tapered bDMARD according to a standardized regime. One-hundred-and-nineteen of these patients were included in this ultrasound sub-study. At baseline, clinical assessment, MRI, x-ray and ultrasound of 24 joints were performed. Ultrasound-detected synovitis was defined and scored 0-3 using the Outcome in Rheumatology (OMERACT) scoring system at joint level for both greyscale and Doppler activity. Sum scores for each ultrasound modality were calculated for 24 joints at patient level. Final state of treatment was assessed after 2 years. The predictive value of ultrasound measures for successful tapering and discontinuation at 2-year follow-up was assessed via logistic regression analyses.

RESULTS

Negative IgM-RF (OR = 0.29; 95% Confidence Interval (CI)=0.10-0.85; p = 0.024) and lower Doppler sum score of 24 joints (OR(95%CI)=0.44;(0.15-0.87); p = 0.014) were independent predictors for successful discontinuation of bDMARD at 2-year follow-up. The predictive value of Doppler sum score was independent of MRI findings. Previous numbers of bDMARDs were predictive of successful tapering (OR(95% CI)=0.58(0.35-0.91); p = 0.018), whereas ultrasound was not. Clinical parameters were not predictive for successful tapering/discontinuation.

CONCLUSIONS

Doppler sum score was an independent predictor for successful discontinuation of bDMARDs at 2-year follow-up - the odds for achieving successful discontinuation decreased by 56% per one-unit increase in Doppler sum score. Ultrasound could not predict successful tapering.

Using a DAS28-CRP-steered treat-to-target strategy does not eliminate subclinical inflammation as assessed by ultrasonography in rheumatoid arthritis patients in longstanding clinical remission

Background

Subclinical synovitis by ultrasound is a frequent finding in rheumatoid arthritis (RA) patients in remission and has been shown to be related to erosive progression, risk of flare and unsuccessful drug tapering, but it has not been investigated how a DAS28 T2T-steered strategy in routine care affects the presence of subclinical synovitis in RA patients in remission. The aim of the current study was to investigate the presence of ultrasound-detected subclinical inflammation in RA patients in long-term remission receiving either biological or conventional disease-modifying anti-rheumatic drugs (bDMARD/csDMARD) and, finally, to investigate the presence of ultrasound remission using different ultrasound remission criteria.

Methods

Eighty-seven RA patients (42 patients receiving bDMARD and 45 csDMARD) received DAS28-CRP-steered treatment in routine care and had achieved DAS28-CRP-remission for > 1 year without radiographic progression. Twenty-four joints were scored 0–3 by ultrasound (elbows, wrists, knees, ankles, metacarpophalangeal and metatarsophalangeal joints 2–5) for grey-scale synovial hypertrophy (GS) and colour Doppler activity (CD) using the OMERACT scoring system. Ultrasound remission was defined as strict (GS score = 0 and CD score = 0), semi-strict (GS score < 1 and Doppler score = 0) and Doppler remission (Doppler score = 0).

Results

No differences between treatment groups were found for GS sum score and Doppler sum score (median (range) 6 (0–19) and 0 (0–12), respectively). A Doppler score > 0 in at least 1 joint was seen in 44%, a GS score > 1 in at least 1 joint in 93% and a GS score > 2 in at least 1 joint in 54% of patients. Strict ultrasound remission was only observed in bDMARD patients (7%; p = 0.01). Thirty-seven per cent were in semi-strict ultrasound remission and 56% in Doppler remission (no significant difference between groups) with similar results across the subgroups of patients who also fulfilled the ACR-EULAR Boolean-, CDAI- and SDAI-remission criteria.

Conclusions

Ultrasound frequently detected subclinical synovitis in RA patients in longstanding DAS28-remission obtained through a DAS28-CRP-steered strategy. This was independent of treatment and applied ultrasound remission criteria. Strict ultrasound remission was rare.

Peripheral Enthesitis Detected by Ultrasonography in Patients With Axial Spondyloarthritis-Anatomical Distribution, Morphology, and Response to Tumor Necrosis Factor-Inhibitor Therapy

Objectives: To investigate the anatomical distribution, morphological abnormalities and response to adalimumab therapy of ultrasound(US)-detected peripheral enthesitis in patients with axial spondyloarthritis (SpA).

Methods: In a randomized, placebo-controlled, double-blinded, investigator-initiated trial (NCT01029847), patients with axial SpA according to the Assessment of Spondyloarthritis International Society criteria were randomized to subcutaneous adalimumab 40 mg every other week or placebo from baseline to week 6. From week 6 to 24, all patients received adalimumab 40 mg every other week. Of 49 patients enrolled, 21 patients participated in our observational US sub-study. US assessment applying the OMERACT US definitions for enthesitis of 10 peripheral entheseal regions of the upper and lower extremities and clinical examination were performed at baseline, weeks 6 and 24. US was performed by one experienced investigator. Hypo-echogenicity, increased thickness and Doppler activity of the enthesis were considered signs of active inflammation, whereas insertional bone erosions, intratendinous calcifications, and enthesophytes were regarded as signs of structural lesions.

Results: Enthesitis on US was mostly present in the lower limbs, especially in the Achilles tendon (81%), the quadriceps tendon (62%), and the greater femoral trochanter (52%). Structural lesions were predominant (38 vs. 12% of examined entheses with inflammatory changes), particularly in the entheses of the lower limbs, and exhibited no change during treatment.

Conclusion: US-detected structural lesions were common while inflammatory lesions were relatively rare in patients initiating adalimumab due to axial SpA. Structural lesions did not appear to change during 24 weeks follow-up, suggesting that these lesions may not be helpful outcome measures in short-term clinical trials.

Assessing Vasculitis in Giant Cell Arteritis by Ultrasound: Results of OMERACT Patient-based Reliability Exercises

Objective.

To test the reliability of Outcome Measures in Rheumatology Clinical Trials (OMERACT) consensus-based ultrasound definitions for normal and vasculitic temporal and axillary arteries in patients with giant cell arteritis (GCA) and in controls.

Methods.

A preliminary 1-day meeting and a full 3-day meeting fulfilling OMERACT Ultrasound Group guidelines were held. Temporal and axillary arteries were examined at 2 timepoints by 12 sonographers on 4 patients with GCA and 2 controls. The aim was to test inter- and intrareader reliability for normal findings, halo sign, and compression sign. In both meetings, patients had established GCA. Pathology was more recent in the full meeting, which was preceded by 6 h of training. Scanning time was 15–20 min instead of 10–13 min.

Results.

In the preliminary exercise, interreader reliabilities were fair to moderate for the overall diagnosis of GCA (Light κ 0.29–0.51), and poor to fair for identifying vasculitis in the respective anatomical segments (Light κ 0.02–0.46). Intrareader reliabilities were moderate (Cohen κ 0.32–0.64). In the main exercise, interreader reliability was good to excellent (Light κ 0.76–0.86) for the overall diagnosis of GCA, and moderate to good (Light κ 0.46–0.71) for identifying vasculitis in the respective anatomical segments. Intrareader reliability was excellent for diagnosis of GCA (Cohen κ 0.91) and good (Cohen κ 0.71–0.80) for the anatomical segments.

Conclusion.

OMERACT-derived definitions of halo and compression signs of temporal and axillary arteries are reliable in recent-onset GCA if experienced sonographers (> 300 examinations) have 15–20 min for a standardized examination with prior training and apply > 15 MHz probes.

Definitions and reliability assessment of elementary ultrasound lesions in giant cell arteritis: a study from the OMERACT Large Vessel Vasculitis Ultrasound Working Group

Objectives

To define the elementary ultrasound (US) lesions in giant cell arteritis (GCA) and to evaluate the reliability of the assessment of US lesions according to these definitions in a web-based reliability exercise.

Methods

Potential definitions of normal and abnormal US findings of temporal and extracranial large arteries were retrieved by a systematic literature review. As a subsequent step, a structured Delphi exercise was conducted involving an expert panel of the Outcome Measures in Rheumatology (OMERACT) US Large Vessel Vasculitis Group to agree definitions of normal US appearance and key elementary US lesions of vasculitis of temporal and extracranial large arteries. The reliability of these definitions on normal and abnormal blood vessels was tested on 150 still images and videos in a web-based reliability exercise.

Results

Twenty-four experts participated in both Delphi rounds. From originally 25 statements, nine definitions were obtained for normal appearance, vasculitis and arteriosclerosis of cranial and extracranial vessels. The ‘halo’ and ‘compression’ signs were the key US lesions in GCA. The reliability of the definitions for normal temporal and axillary arteries, the ‘halo’ sign and the ‘compression’ sign was excellent with inter-rater agreements of 91–99% and mean kappa values of 0.83–0.98 for both inter-rater and intra-rater reliabilities of all 25 experts.

Conclusions

The ‘halo’ and the ‘compression’ signs are regarded as the most important US abnormalities for GCA. The inter-rater and intra-rater agreement of the new OMERACT definitions for US lesions in GCA was excellent.

Investigation of a multi-biomarker disease activity score in rheumatoid arthritis by comparison with magnetic resonance imaging, computed tomography, ultrasonography, and radiography parameters of inflammation and damage

OBJECTIVES

To investigate the multi-biomarker disease activity (MBDA) score by comparison with imaging findings in an investigator-initiated rheumatoid arthritis (RA) trial (HURRAH trial, NCT00696059).

METHOD

Fifty-two patients with established RA initiated adalimumab treatment and had magnetic resonance imaging (MRI), ultrasonography (US), computed tomography (CT), and radiography performed at weeks 0, 26, and 52. Serum samples were analysed using MBDA score assays and associations between clinical measures, MBDA score, and imaging findings were investigated.

RESULTS

The MBDA score correlated significantly with MRI synovitis (rho = 0.65, p < 0.001), MRI bone marrow oedema (rho = 0.36, p = 0.044), and US power Doppler (PD) score at week 26 (rho = 0.35, p = 0.039) but not at week 0 or week 52. In the 15 patients who had achieved a Disease Activity Score based on C-reactive protein (DAS28-CRP) < 2.6 at week 26, MRI and/or US detected subclinical inflammation and 13 (87%) had a moderate/high MBDA score. For the cohort with available data, none of the four patients in MBDA remission (score ≤ 25) at week 26 had progression of imaging damage from baseline to week 52 whereas progression was observed in three out of nine (33%) and seven out of 21 (33%) patients with moderate (30-44) and high (> 44) MBDA scores, respectively.

CONCLUSIONS

In this cohort, the MBDA score correlated poorly with MRI/US inflammation. However, the MBDA score and MRI/US were generally concordant in showing signs of inflammation in most patients in clinical remission during anti-tumour necrosis factor (anti-TNF) therapy. MBDA scores were elevated in all patients with structural damage progression.

Intramuscular versus ultrasound-guided intratenosynovial glucocorticoid injection for tenosynovitis in patients with rheumatoid arthritis: a randomised, double-blind, controlled study

OBJECTIVE

The aim of this study was to compare the efficacy of intramuscular versus ultrasound (US)-guided intratenosynovial glucocorticoid injection in providing disease control after 2, 4 and 12 weeks in patients with rheumatoid arthritis(RA) with tenosynovitis.

METHODS

Fifty patients with RA and tenosynovitis were randomised into two double-blind groups: (A) 'intramuscular group', receiving intramuscular injection of betamethasone and US-guided intratenosynovial isotonic saline injection and (B) 'intratenosynovial group' receiving saline intramuscularly and US-guided intratenosynovial betamethasone injection. All patients were in stable disease-modifying anti-rheumatic drug treatment prior to and during the study. Patients were excluded, and considered non-responders, if any treatments were altered during the follow-up period. 'US tenosynovitis remission', defined as US tenosynovitis grey-scale score ≤1 and colour Doppler score=0, was assessed at week 4 (primary outcome), and weeks 2 and 12, using non-responder imputation for missing data.

RESULTS

US tenosynovitis remission at week 4 was achieved in 25% (6/24) in the 'intramuscular group' versus 64% (16/25) in the 'intratenosynovial group', that is, a difference of -39 percentage point (pp) (CI -65pp to -13pp), Fisher exact test p=0.001. Corresponding values for the 'intramuscular group' versus the 'intratenosynovial group' at 2 and 12 weeks were 21% (5/24) versus 48% (13/25), that is, a difference of -27pp (CI -53pp to -2pp), p=0.072 and 8% (2/24) versus 44% (11/25), that is, difference of -36pp (-58pp to -13pp), p=0.003. Most US, clinical and patient-reported scores improved more in the 'intratenosynovial group' at all follow-up visits.

CONCLUSIONS

In this randomised double-blind clinical trial, patients with RA and tenosynovitis responded significantly better to US-guided intratenosynovial glucocorticoid injection than to intramuscular glucocorticoid injection, both at 4 and 12 weeks follow-up.

TRIAL REGISTRATION NUMBER

EudraCT nr: 2013-003486-34.

Determining a Magnetic Resonance Imaging Inflammatory Activity Acceptable State Without Subsequent Radiographic Progression in Rheumatoid Arthritis: Results from a Followup MRI Study of 254 Patients in Clinical Remission or Low Disease Activity

Objective.

To assess the predictive value of magnetic resonance imaging (MRI)-detected subclinical inflammation for subsequent radiographic progression in a longitudinal study of patients with rheumatoid arthritis (RA) in clinical remission or low disease activity (LDA), and to determine cutoffs for an MRI inflammatory activity acceptable state in RA in which radiographic progression rarely occurs.

Methods.

Patients with RA in clinical remission [28-joint Disease Activity Score-C-reactive protein (DAS28-CRP) < 2.6, n = 185] or LDA state (2.6 ≤ DAS28-CRP < 3.2, n = 69) with longitudinal MRI and radiographic data were included from 5 cohorts (4 international centers). MRI were assessed according to the Outcome Measures in Rheumatology (OMERACT) RA MRI scoring system (RAMRIS). Statistical analyses included an underlying conditional logistic regression model stratified per cohort, with radiographic progression as dependent variable.

Results.

A total of 254 patients were included in the multivariate analyses. At baseline, synovitis was observed in 95% and osteitis in 49% of patients. Radiographic progression was observed in 60 patients (24%). RAMRIS synovitis was the only independent predictive factor in multivariate analysis. ROC analysis identified a cutoff value for baseline RAMRIS synovitis score of 5 (maximum possible score 21). Rheumatoid factor (RF) status yielded a significant interaction with synovitis (p value = 0.044). RF-positive patients with a RAMRIS synovitis score of > 5 vs ≤ 5, had an OR of 4.4 (95% CI 1.72–11.4) for radiographic progression.

Conclusion.

High MRI synovitis score predicts radiographic progression in patients in clinical remission/LDA. A cutoff point for determining an MRI inflammatory activity acceptable state based on the RAMRIS synovitis score was established. Incorporating MRI in future remission criteria should be considered.

Update on the OMERACT Magnetic Resonance Imaging Task Force: Research and Future Directions

Magnetic resonance imaging (MRI) provides an important biomarker across a range of rheumatological diseases. At the Outcome Measures in Rheumatology (OMERACT) 11 meeting, the MRI task force continued its work of developing and improving the use of MRI outcomes for use in clinical trials. The breadth of pathology in the Rheumatoid Arthritis MRI Score has been strengthened with further work on the development of a joint space narrowing score, and a series of exercises presented at OMERACT 11 demonstrated good reliability and construct validity for this assessment. Understanding the importance of residual inflammation after RA treatment remains a major focus of the group’s work. Analyses were presented on defining the level of synovitis (using MRI scores of a single hand) that would predict absence of erosion progression. The development of the OMERACT Hand Osteoarthritis MRI score has continued with substantial work presented on its iterative development, including pathology definition, scaling, and subsequent reliability of the score. Optimizing the role of MRI as a robust biomarker and surrogate outcome remains a priority for this group.

The OMERACT-RAMRIS Rheumatoid Arthritis Magnetic Resonance Imaging Joint Space Narrowing Score: Intrareader and Interreader Reliability and Agreement with Computed Tomography and Conventional Radiography

Objective.

To test the intrareader and interreader reliability of assessment of joint space narrowing (JSN) in rheumatoid arthritis (RA) wrist and metacarpophalangeal (MCP) joints on magnetic resonance imaging (MRI) and computed tomography (CT) using the newly proposed OMERACT-RAMRIS JSN scoring method, and to compare JSN assessment on MRI, CT, and radiography.

Methods.

After calibration of readers, MRI and CT images of the wrist and second to fifth MCP joints from 14 patients with RA and 1 healthy control were assessed twice for JSN by 3 readers, blinded to clinical and imaging data. Radiographs were scored by the Sharp/van der Heijde method. Intraclass correlation coefficients (ICC) and smallest detectable differences (SDD) were calculated, and the performance of various simplified scores was investigated.

Results.

Both MRI and CT showed high intrareader (ICC ≥ 0.95) and interreader (ICC ≥ 0.94) reliability for total (wrist + MCP) assessment of JSN. Agreement was generally lower for MCP joints than for wrist joints, particularly for CT. Intrareader SDD for MCP/wrist/MCP + wrist were 1.2/6.1/6.4 JSN units for MRI, while 2.7/8.3/9.9 JSN units for CT. JSN on MRI and CT correlated moderately well with corresponding radiographic JSN scores (MCP 2–5: 0.49 and 0.56; wrist areas assessed by Sharp/van der Heijde: 0.80 and 0.95), and high ICC between scores on MRI and CT were demonstrated (MCP: 0.94; wrist: 0.92; MCP + wrist: 0.92).

Conclusion.

The OMERACT-RAMRIS MRI JSN scoring system showed high intrareader and interreader reliability, and high correlation with CT scores of JSN. The suggested JSN score may, after further validation in longitudinal studies, become a useful tool in RA clinical trials.

Patterns of magnetic resonance imaging bone erosion in rheumatoid arthritis--which bones are most frequently involved and show the most change?

OBJECTIVE

To investigate by magnetic resonance imaging (MRI) which bones in wrists and metacarpophalangeal (MCP) joints most frequently show bone erosions, and which most frequently demonstrate erosive progression, in early and established rheumatoid arthritis (RA).

METHODS

MRI datasets from 258 RA patients [126 with early RA (disease duration < 6 months)] were analyzed, of whom 223, including 126 with early RA, had 1-year followup MRI. All patients had MRI of one wrist, whereas 86 patients had additional images of 2nd-5th MCP joints, and 46 patients additional images of the contralateral wrist. MRI were evaluated blinded by one reader, according to the OMERACT RA MRI scoring system (RAMRIS) for erosions, and presence/absence of erosions was noted in each bone, as was presence/absence of erosive progression.

RESULTS

The capitate, ulna, lunate, triquetrum, and scaphoid were the 5 bones with both most frequent baseline erosions and most frequently demonstrated erosive progression. No bones were without erosions. Patterns of erosions and progression were similar in early and established RA. No major difference between dominant and nondominant wrists was detected. In the fingers, the 2nd-3rd MCP joint most frequently displayed erosions and erosive progression.

CONCLUSION

The distribution and frequency of bone erosion and erosive progression as detected by MRI in RA wrists and MCP joints were identified. No pattern differences between early versus established disease and dominant versus nondominant sides were detected. No bones showed erosive progression. Thus, no self-evident simplification of the RAMRIS erosion score was identified. Bone involvement patterns may be considered, when joints are selected for MRI protocols for clinical trials and practice.

Detection, scoring and volume assessment of bone erosions by ultrasonography in rheumatoid arthritis: comparison with CT

OBJECTIVES

To determine the accuracy of ultrasonography (US) for bone erosion detection in different areas of rheumatoid arthritis (RA) metacarpophalangeal (MCP) joints with multislice CT as the reference method. Second, to establish the necessary bone volume loss on CT for US to reliably detect it as an erosion, and finally to compare two semiquantitative US-erosion scoring methods.

METHODS

The 2nd-5th MCP joints of 49 patients with RA were examined by CT and US, and evaluated for the presence of bone erosion in each MCP joint quadrant. On CT, erosion volume was scored according to the OMERACT-RAMRIS score (bone volume loss in 10% increments of original bone volume). US erosions were scored 0-3 according to the Szkudlarek and Scoring by UltraSound Structural erosion (ScUSSe) systems, respectively.

RESULTS

Seven hundred and eighty-four MCP joint quadrants were examined. Erosions were detected by CT in 259 quadrants and by US in 142 quadrants. Sensitivity/specificity/accuracy of US was overall 44%/95%/78% compared with 71%/95%/90% in areas with good US accessibility (radial 2nd MCP, ulnar 5th MCP and all dorsal/palmar aspects). US detected 95% of erosions with bone volume loss >20%. In US accessible areas, 63% of erosions with 1-10% bone volume loss and 94% of erosions with >10% bone loss were detected. The two US scoring systems agreed well on large erosions, whereas the smallest erosions (Szkudlarek grade 1, of which 86% were confirmed by CT) were not scored by ScUSSe.

CONCLUSION

In accessible areas, US was highly accurate for detection and semiquantitative assessment of RA bone erosion. Even the smallest erosions, only detected in one plane, were generally confirmed by CT.

Development and preliminary validation of a magnetic resonance imaging joint space narrowing score for use in rheumatoid arthritis: potential adjunct to the OMERACT RA MRI scoring system

OBJECTIVE

To develop and validate a magnetic resonance imaging (MRI) method of assessment of joint space narrowing (JSN) in rheumatoid arthritis (RA).

METHODS

Phase A: JSN was scored 0-4 on MR images of 5 RA patients and 3 controls at 15 wrist sites and 2nd-5th metacarpophalangeal (MCP) joints by 8 readers (7 once, one twice), using a preliminary scoring system. Phase B: Image review, discussion, and consensus on JSN definition, and revised scoring system. Phase C: MR images of 15 RA patients and 4 controls were scored using revised system by 5 readers (4 once, one twice), and results compared with radiographs [Sharp-van der Heijde (SvdH) method].

RESULTS

Phase A: Intraobserver agreement: intraclass correlation coefficient (ICC) = 0.99; smallest detectable difference (SDD, for mean of readings) = 2.8 JSN units (4.9% of observed maximal score). Interobserver agreement: ICC = 0.93; SDD = 6.4 JSN units (9.9%). Phase B: Agreement was reached on JSN definition (reduced joint space width compared to normal, as assessed in a slice perpendicular to the joint surface), and revised scoring system (0-4 at 17 wrist sites and 2nd-5th MCP; 0: none; 1: 1-33%; 2: 34-66%; 3: 67-99%; 4: ankylosis). Phase C: Intraobserver agreement: ICC = 0.90; SDD = 6.8 JSN units (11.0%). Interobserver agreement: ICC = 0.92 and SDD = 6.2 JSN units (8.7%). The correlation (ICC) with the SvdH radiographic JSN score of the wrist/hand was 0.77. Simplified approaches evaluating fewer joint spaces demonstrated similar reliability and correlation with radiographic scores.

CONCLUSION

An MRI scoring system of JSN in RA wrist and MCP joints was developed and showed construct validity and good intra- and interreader agreements. The system may, after further validation in longitudinal data sets, be useful as an outcome measure in RA.

No overall progression and occasional repair of erosions despite persistent inflammation in adalimumab-treated rheumatoid arthritis patients: results from a longitudinal comparative MRI, ultrasonography, CT and radiography study

AIM

To monitor joint inflammation and destruction in rheumatoid arthritis (RA) patients receiving adalimumab/methotrexate combination therapy using MRI and ultrasonography. To assess the predictive value of MRI and ultrasonography for erosive progression on CT and compare MRI/ultrasonography/radiography for erosion detection/monitoring.

METHODS

Fifty-two erosive biological-naive RA patients were followed with repeated MRI/ultrasonography/radiography (0/6/12 months) and clinical/biochemical assessments during adalimumab/methotrexate combination therapy.

RESULTS

No overall erosion progression or repair was observed at 6 or 12 months (Wilcoxon; p > 0.05), but erosion progressors and regressors were observed using the smallest detectable change cut-off. Scores of MRI synovitis, grey-scale synovitis (GSS) and power Doppler ultrasonography decreased after 6 and 12 months (p < 0.05), as did DAS28, HAQ and tender and swollen joint counts (p < 0.001). Patients with progression on CT had higher baseline MRI bone oedema scores. The RR for CT progression in bones with versus without baseline MRI bone oedema was 3.8 (95% CI 1.5 to 9.3) and time-integrated MRI bone oedema, power Doppler and GSS scores were higher in bones/joints with CT progression (Mann-Whitney; p < 0.05). With CT as the reference method, sensitivities/specificities for erosion in metacarpophalangeal joints were 68%/92%, 44%/95% and 26%/98% for MRI, ultrasonography and radiography, respectively. Median intraobserver correlation coefficient was 0.95 (range 0.44-0.99).

CONCLUSION

During adalimumab/methotrexate combination therapy, no overall erosive progression or repair occurred, whereas repair of individual erosions was documented on MRI, and MRI and ultrasonography synovitis decreased. Inflammation on MRI and ultrasonography, especially MRI bone oedema, was predictive for erosive progression on CT, at bone/joint level and MRI bone oedema also at patient level.

Imaging in rheumatoid arthritis--status and recent advances for magnetic resonance imaging, ultrasonography, computed tomography and conventional radiography

Sensitive and reproducible tools for diagnosis, monitoring of disease activity and damage, and prognostication are essential in the management of patients with rheumatoid arthritis (RA). Conventional radiography (X-ray), the traditional gold standard for imaging in RA, is not able to detect early disease manifestations such as inflammatory changes in the soft tissues (synovitis, tensynovitis, enthesitis etc.) and the earliest stages of bone erosion. In contrast, magnetic resonance imaging (MRI) and ultrasonography (US) allow direct visualization of early inflammatory and destructive joint changes, and have several documented and potential applications in RA patients. This chapter will review key aspects of the current status and recent important advances in imaging in RA, briefly discussing X-ray and computed tomography, and particularly focusing on MRI and US. Suggestions for use in clinical trials and practice are provided.

Detection of bone erosions in rheumatoid arthritis wrist joints with magnetic resonance imaging, computed tomography and radiography

BACKGROUND

The objectives of the present study were, with multidetector computed tomography (CT) as the reference method, to determine the performance of magnetic resonance imaging (MRI) and radiography for the detection of bone erosions in rheumatoid arthritis wrist bones, and to test whether measuring volumes of erosions on CT and MRI is reproducible and correlated to semiquantitative assessments (scores) of erosions on CT, MRI and radiography.

METHODS

Seventeen patients with rheumatoid arthritis and four healthy control individuals underwent CT, MRI and radiography of one wrist, performed on the same day. CT was performed on a Philips Mx8000IDT unit (voxel size 0.4 mm x 0.4 mm x 1 mm) and MRI was performed on a Philips Panorama 0.6T unit (voxel size 0.4 mm x 0.4 mm x 0.4 mm). Images were evaluated separately for erosions in all wrist bones and were scored according to the principles of the Outcome Measures in Rheumatology Rheumatoid Arthritis MRI Scoring System (CT and MRI) and the Sharp/van der Heijde (radiographs) scoring methods. Measurements of erosion volumes of all erosions were performed twice with a 1-week interval.

RESULTS

With CT as the reference method, the overall sensitivity, specificity and accuracy (concordance) of MRI for detecting erosions were 61%, 93% and 77%, respectively, while the respective values were 24%, 99% and 63% for radiography. The intramodality agreements when measuring erosion volumes were high for both CT and MRI (Spearman correlation coefficients 0.92 and 0.90 (both P < 0.01), respectively). Correlations between volumes and scores of individual erosions were 0.96 for CT and 0.99 for MRI, while they were 0.83 (CT) and 0.80 (MRI) for persons' total erosion volume and total score (all P < 0.01).

CONCLUSION

With CT as the reference method, MRI showed moderate sensitivity and good specificity and accuracy for detection of erosions in rheumatoid arthritis and healthy wrist bones, while radiography showed very low sensitivity. The tested volumetric method was highly reproducible and correlated to scores of erosions.

Detection of rheumatoid arthritis bone erosions by two different dedicated extremity MRI units and conventional radiography

OBJECTIVES

To compare the ability of two different dedicated extremity MRI (E-MRI) units and conventional radiography (CR) for identifying bone erosions in rheumatoid arthritis (RA) metacarpophalangeal (MCP) and wrist joints.

METHODS

CR and two MRI examinations (using 0.2 T Esaote Artoscan and 0.2 T portable MagneVu MV1000 units) of 418 bones in the dominant wrist and second to fifth MCP joints of 15 patients with RA and 4 healthy controls were performed and evaluated blindly for bones being visible and for erosions.

RESULTS

In MCP joints, MagneVu visualised 18.5% of bones entirely and 71.1% were 67-99% visualised. In wrists, MagneVu visualised 1.5% of bones entirely, 39.8% were 67-99% visualised and 19% were not visualised at all. Artoscan and CR visualised all bones entirely. Artoscan, MagneVu and CR found 22, 19 and 15 bones with erosions in MCP joints and 66, 40 and 13 bones with erosions in wrist joints, respectively. With the previously validated Artoscan unit as standard reference, MagneVu and CR had sensitivities of 0.82 and 0.55, respectively, in MCP joint bones and 0.41 and 0.14 in wrist bones. Specificities of CR and MagneVu were comparable (0.82-0.99). The MagneVu unit was particularly more sensitive than CR for metacarpal heads and carpal bones. MagneVu MRI and CR detected 100% and 89%, respectively, of large erosions (Outcome Measures in Rheumatoid Arthritis Clinical Trials-Rheumatoid Arthritis MRI Scoring System (OMERACT-RAMRIS) score >1 on Artoscan) in MCP joints and 69% and 15.8% of large erosions in wrists.

CONCLUSIONS

Both E-MRI units detected more erosions than CR, in particular due to a higher sensitivity in metacarpal heads and carpal bones. The MagneVu unit detected fewer erosions than the Artoscan unit due to a lower average image quality and a smaller proportion of bones being visualised.

Rheumatoid arthritis bone erosion volumes on CT and MRI: reliability and correlations with erosion scores on CT, MRI and radiography

OBJECTIVES

To investigate intramodality and intermodality agreements of CT and MRI erosion volumes in metacarpophalangeal (MCP) joints in rheumatoid arthritis (RA), and to compare the volumes with erosion scores for CT, MRI and radiography.

METHODS

In total, 17 patients with RA and four healthy controls underwent unilateral CT, MRI and radiography of second to fifth MCP joints in one hand. Erosion volumes (using OSIRIS software) and scores were determined from CT, MRI and radiography (scores only).

RESULTS

CT, MRI and radiography detected 77, 62 and 12 erosions, respectively. On CT, the mean erosion volume was 26 mm(3) (median 10; range 0 to 248) and 30 mm(3) (18; 1 to 163) on MRI. Total erosion volumes (per patient/control) were 97 mm(3) (29; 0 to 485) on CT and 90 mm(3) (46; 0 to 389) on MRI. For volumes, Spearman correlation coefficients were 0.96 to 0.99 (CT vs CT), 0.95 to 0.98 (MRI vs MRI) and 0.64 to 0.89 (CT vs MRI), all p<0.01. MRI erosion volumes correlated with the Outcome Measures in Rheumatology Clinical Trials/Rheumatoid Arthritis Magnetic Resonance Imaging Score (OMERACT RAMRIS) erosion scores (0.91 to 0.99; p<0.01) and the Sharp/van der Heijde erosion score (0.49 to 0.63; p<0.01).

CONCLUSION

Very high intramodality and high intermodality agreements of CT and MRI erosion volumes were found, encouraging further testing in longitudinal studies. A close correlation with CT and MRI erosion volumes supports the OMERACT RAMRIS erosion score as a valid measure of joint destruction in RA.

No erosive progression revealed by MRI in rheumatoid arthritis patients treated with etanercept, even in patients with persistent MRI and clinical signs of joint inflammation

The aim of this study is to investigate the course of magnetic resonance imaging (MRI) signs of inflammatory and destructive changes in rheumatoid arthritis (RA) wrist and metacarpophalangeal (MCP) joints during etanercept treatment. MRI of the non-dominant wrist and second to fifth MCP joints was performed in five clinical active RA patients before and 4 and 16 weeks after initiation of etanercept treatment. MRI was evaluated according to the EULAR-OMERACT RA MRI reference image atlas. The median 28-joint count disease activity score (DAS28; erythrocyte sedimentation rate based) was 5.6 (range 5.0-6.8) at baseline and 3.5 (1.5-4.1) at week 16 (decreased in all patients compared to baseline, Wilcoxon-Pratt, p < 0.05). The median MRI synovitis score was 18 (14-21), 18 (10-20) and 16 (10-20) at baseline, week 4 and 16, respectively (decreased in all patients compared to baseline, Wilcoxon-Pratt, p < 0.05), while corresponding MRI bone oedema scores were 4 (0-13), 3 (0-9) and 1 (0-3; NS). The median MRI bone erosion score was 27 (11-111; NS) at all time points. Four patients had identical total bone erosion scores at baseline and week 16, whereas one patient showed a reduced score. In conclusion, one patient showed erosive regression, while no patient showed erosive progression on MRI during 16 weeks of etanercept therapy; even though clinical and MRI signs of joint inflammation remained. This small study supports that erosive progression judged by MRI is minimal in RA patients treated with etanercept, even in joints with persistent inflammation.

Are bone erosions detected by magnetic resonance imaging and ultrasonography true erosions? A comparison with computed tomography in rheumatoid arthritis metacarpophalangeal joints

The objective of the study was, with multidetector computed tomography (CT) as the reference method, to determine whether bone erosions in rheumatoid arthritis (RA) metacarpophalangeal (MCP) joints detected with magnetic resonance imaging (MRI) and ultrasonography (US), but not with radiography, represent true erosive changes. We included 17 RA patients with at least one, previously detected, radiographically invisible MCP joint MRI erosion, and four healthy control individuals. They all underwent CT, MRI, US and radiography of the 2nd to 5th MCP joints of one hand on the same day. Each imaging modality was evaluated for the presence of bone erosions in each MCP joint quadrant. In total, 336 quadrants were examined. The sensitivity, specificity and accuracy, respectively, for detecting bone erosions (with CT as the reference method) were 19%, 100% and 81% for radiography; 68%, 96% and 89% for MRI; and 42%, 91% and 80% for US. When the 16 quadrants with radiographic erosions were excluded from the analysis, similar values for MRI (65%, 96% and 90%) and US (30%, 92% and 80%) were obtained. CT and MRI detected at least one erosion in all patients but none in control individuals. US detected at least one erosion in 15 patients, however, erosion-like changes were seen on US in all control individuals. Nine patients had no erosions on radiography. In conclusion, with CT as the reference method, MRI and US exhibited high specificities (96% and 91%, respectively) in detecting bone erosions in RA MCP joints, even in the radiographically non-erosive joints (96% and 92%). The moderate sensitivities indicate that even more erosions than are seen on MRI and, particularly, US are present. Radiography exhibited high specificity (100%) but low sensitivity (19%). The present study strongly indicates that bone erosions, detected with MRI and US in RA patients, represent a loss of calcified tissue with cortical destruction, and therefore can be considered true bone erosions.