Assessment of cartilage loss at the wrist in rheumatoid arthritis using a new MRI scoring system

OBJECTIVES

To develop and test an MRI cartilage scoring system for use at the wrist in rheumatoid arthritis (RA).

METHODS

MRI scans were obtained using a 3T MRI scanner with dedicated wrist coil in 22 early and 16 established RA patients plus 22 controls. Axial and coronal T1-weighted (precontrast and postcontrast) and T2-weighted turbo spin echo sequences were obtained. Eight wrist joints were scored for cartilage narrowing: distal radioulnar, radiolunate, radioscaphoid, triquetrum-hamate, capitate-lunate, scaphotrapezoid, second metacarpal base-trapezoid and third metacarpal base-capitate, using a system based on the Sharp van der Heijde x-ray joint space narrowing (JSN) score by three radiologists. Fifteen sites at the wrist were also scored for synovitis, bone oedema and erosion using the RA MRI score.

RESULTS

Interobserver (three-reader) and intraobserver reliability (readers 1 and 2) for the cartilage score were excellent: intraclass correlations (ICC (95% CI)) 0.91, (0.86 to 0.94), 0.98 (0.96 to 1.00) and 0.94 (0.87 to 1.00), respectively. Cartilage scores (median, range) were higher in the established RA group (11.9, 2.3-27.3) than the early RA group (2.15, 0-6) (p≤0.001) but early RA scores did not differ from healthy controls (2.3, 1-8.7). Cartilage scores correlated with synovitis (R=0.52), bone oedema (R=0.63) and erosion scores (R=0.66), p<0.001 for all, and with x-ray JSN scores (R=0.68 to 0.78).

CONCLUSION

This MRI cartilage score demonstrated excellent reliability when tested in a three-reader system. However, cartilage loss in early RA could not be distinguished from that seen in healthy controls.

Outcome domains for studies of acute and chronic gout

Discussion and voting at OMERACT 9 confirmed 5 essential domains for outcomes of acute gout: pain, joint swelling, joint tenderness, patient global assessment and activity limitations. For studies in chronic gout 7 essential domains are: serum urate, acute gout attacks, tophus burden, health-related quality of life, activity limitations, pain, and patient global assessment. Implications of patient perspectives, discretionary domains for specific studies, measurement instruments and a possible responder index are under study.

A modified Delphi exercise to determine the extent of consensus with OMERACT outcome domains for studies of acute and chronic gout

OBJECTIVES

To reach consensus with recommendations made by an OMERACT Special Interest Group (SIG).

METHODS

Rheumatologists and industry representatives interested in gout rated and clarified, in three iterations, the importance of domains proposed by the OMERACT SIG for use in acute and chronic gout intervention studies. Consensus was defined as a value of less than 1 of the UCLA/RAND disagreement index.

RESULTS

There were 33 respondents (61% response rate); all agreed the initial items were necessary, except "total body urate pool". Additional domains were suggested and clarification sought for defining "joint inflammation" and "musculoskeletal function". Items that demonstrated no clear decision were re-rated in the final iteration. There were six highly rated items (rating 1-2) with four slightly lower rating items (rating 3) for acute gout; and 11 highly rated items with eight slightly lower ratings for chronic gout.

CONCLUSIONS

Consensus is that the following domains be considered mandatory for acute gout studies: pain, joint swelling, joint tenderness, patient global, physician global, functional disability; and for chronic gout studies: serum urate, gout flares, tophus regression, health-related quality of life, functional disability, pain, patient global, physician global, work disability and joint inflammation. Several additional domains were considered discretionary.

A multireader reliability study comparing conventional high-field magnetic resonance imaging with extremity low-field MRI in rheumatoid arthritis

The use of extremity low-field magnetic resonance imaging (E-MRI) is increasing, but relatively few data exist on its reproducibility and accuracy in comparison with high-field MRI, especially for multiple readers. The aim of this multireader exercise of rheumatoid arthritis wrist and metacarpophalangeal joints was to assess the intermachine (high vs low-field) agreement and to assess the interreader agreement on high and low-field images. Study findings suggested that E-MRI performs similarly to conventional high-field MRI regarding assessment of bone erosions. However, for synovitis and bone edema, considerable intermachine and interreader variability was found. Further studies are needed before recommendations on multireader E-MRI assessment of these pathologies can be given.

A multicenter reliability study of extremity-magnetic resonance imaging in the longitudinal evaluation of rheumatoid arthritis

There are limited data on the reliability of extremity magnetic resonance imaging (E-MRI) in the longitudinal evaluation of rheumatoid arthritis (RA). Our aim was to assess the interreader reliability of the OMERACT RA MRI score in the assessment of change in disease activity and bone erosion scores using 0.2 T E-MRI hand and wrist images from 2 timepoints, evaluated by 3 readers at different international centers. The intraclass correlation coefficients and smallest detectable difference results for the change scores were generally good for erosions and synovitis, but were not acceptable for bone edema. Overall, E-MRI demonstrated ability to detect change comparable to that reported for high-field MRI for erosion and synovitis.

Developing a magnetic resonance imaging scoring system for peripheral psoriatic arthritis

We describe the first steps in developing an OMERACT magnetic resonance imaging (MRI) scoring system for peripheral psoriatic arthritis (PsA). A preexisting MRI dataset (finger joints) from 10 patients with PsA was scored by 4 readers for bone erosion, bone edema, synovitis, tendinopathy, and extracapsular features of inflammation (including enthesitis) according to specified criteria. Scoring reliability between readers was moderate to high for bone edema and erosion, but lower for soft tissue inflammation. Measures to improve reliability for future exercises will include reviewing definitions of pathological features and prior reader calibration.

The OMERACT Magnetic Resonance Imaging Inflammatory Arthritis Group - advances and priorities

This article updates the work and research priorities of the OMERACT working group on magnetic resonance imaging (MRI) in inflammatory arthritis, as presented to the OMERACT 8 meeting in Malta in May 2006. This work focused on testing the reliability of dedicated extremity MRI in rheumatoid arthritis and on the initial steps in the development of an MRI score for peripheral psoriatic arthritis.

Validation of a radiographic damage index in chronic gout

OBJECTIVE

To identify a valid method to measure radiographic damage in patients with chronic gout.

METHODS

The scoring method that best represented radiographic damage in individual joints was analyzed by comparing a gold standard rheumatologist consensus global score with recognized scoring methods, including the Sharp/van der Heijde erosion and narrowing scores, Ratingen destruction score, and Steinbrocker score. Ninety-five proximal interphalangeal joints from 12 patients with gout were included in this analysis. Scoring of hand and feet radiographs from an additional 35 patients with gout was used to analyze the sites to be included in a scoring system and the additional features to be recorded.

RESULTS

For individual joints, the combination of the Sharp/van der Heijde erosion and narrowing scores correlated best with the consensus global score. In addition, the limits of agreement were narrowest for the combined Sharp/van der Heijde erosion and narrowing score. All joint areas in the Sharp/van der Heijde rheumatoid arthritis score and the distal interphalangeal joints were affected by chronic gout and contributed to the total score. Additional features (extraarticular erosions, joint space widening, and ankylosis) occurred infrequently, and scoring of these features did not increase the reliability of the total score. The reliability of the total score was high: intraclass correlation coefficient for intraobserver reproducibility was 0.993-0.998 and for interobserver reproducibility was 0.963-0.966. The modified Sharp/van der Heijde score was able to discriminate between early and advanced disease.

CONCLUSION

A modified Sharp/van der Heijde system accurately and reliably represents radiographic joint damage in chronic gout.

Using a quality control approach to define an 'adequately cellular' liquid-based cervical cytology specimen

OBJECTIVE

To define a minimum acceptable total squamous cellularity for (ThinPrep) liquid-based cervical cytology (LBC) specimens using quality control techniques.

METHODS

Two hundred LBC preparations were made containing varying numbers (<200) of severely dyskaryotic squamous cells and with varying total cellularities.

RESULTS

Ninety-eight per cent of the LBC preparations that were missed by one or more of three cytoscreeners had fewer than 16 abnormal objects (single dyskaryotic cells or clumps of cells) and 87 dyskaryotic cells. The minimum ratio of dyskaryotic to total squamous cells that, in a preparation of 5000 squamous cells has a probability of at least 0.98 that 87 or more dyskaryotic cells will be present is 1:47. Twenty-three preparations diagnosed as abnormal had ratios of dyskaryotic to total squamous cells of between 1:2.5 and 1:4596. There is thus no feasible minimum acceptable squamous cellularity that will give an acceptable probability of detection of all specimen vials containing abnormal cells in the observed proportions.

CONCLUSIONS

It is suggested that the minimum acceptable cellularity for LBC specimens is set pragmatically by the screening programme to give a feasible percentage of repeat tests.

Magnetic resonance imaging in psoriatic arthritis: a review of the literature

Psoriatic arthritis is a diverse condition that may be characterized by peripheral inflammatory arthritis, axial involvement, dactylitis and enthesitis. Magnetic resonance imaging (MRI) allows visualization of soft tissue, articular and entheseal lesions, and provides a unique picture of the disease process that cannot be gained using other imaging modalities. This review focuses on the literature on MRI in psoriatic arthritis published from 1996 to July 2005. The MRI features discussed include synovitis, tendonitis, dactylitis, bone oedema, bone erosions, soft tissue oedema, spondylitis/sacroiliitis and subclinical arthropathy. Comparisons have been drawn with the more extensive literature describing the MRI features of rheumatoid arthritis and ankylosing spondylitis.

Pitfalls in scoring MR images of rheumatoid arthritis wrist and metacarpophalangeal joints

This paper outlines the most important pitfalls which are likely to be encountered in the assessment of magnetic resonance images of the wrist and metacarpophalangeal joints in patients with rheumatoid arthritis. Imaging artefacts and how these can be recognised using various sequences and views are discussed. Normal structures such as interosseous ligaments and nutrient foramina may appear prominent on certain images and need to be identified correctly. Pathological change in the rheumatoid hand involves many tissues and when substantial damage has occurred, it may be difficult to identify individual structures correctly. Bone erosion, bone oedema, synovitis, and tenosynovitis frequently occur together and in close proximity to each other, potentially leading to false positive scoring of any of these. Examples are given to illustrate the various dilemmas the user of this atlas may face when scoring the rheumatoid hand and suggestions are made to assist correct interpretation of what can be very complex images.

The EULAR-OMERACT rheumatoid arthritis MRI reference image atlas: the metacarpophalangeal joints

This paper presents the metacarpophalangeal (MCP) joint magnetic resonance images of the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas. The illustrations include synovitis in the MCP joints (OMERACT RA magnetic resonance imaging scoring system (RAMRIS), grades 0-3), bone oedema in the metacarpal head and the phalangeal base (grades 0-3), and bone erosion in the metacarpal head and the phalangeal base (grades 0-3, and examples of higher grades). The presented reference images can be used to guide scoring of MCP joints according to the OMERACT RA MRI scoring system.

An introduction to the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas

This article gives a short overview of the development and characteristics of the OMERACT rheumatoid arthritis MRI scoring system (RAMRIS), followed by an introduction to the use of the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas. With this atlas, MRIs of wrist and metacarpophalangeal joints of patients with rheumatoid arthritis can be scored for synovitis, bone oedema, and bone erosion, guided by standard reference images.

The development of the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas

Based on a previously developed rheumatoid arthritis MRI scoring system (OMERACT 2002 RAMRIS), the development team agreed which joints, MRI features, MRI sequences, and image planes would best illustrate the scoring system in an atlas. After collecting representative examples for all grades for each abnormality (synovitis, bone oedema, and bone erosion), the team met for a three day period to review the images and choose by consensus the most illustrative set for each feature, site, and grade. A predefined subset of images (for example, for erosion--all coronal slices through the bone) was extracted. These images were then re-read by the group at a different time point to confirm the scores originally assigned. Finally, all selected images were photographed and formatted by one centre and distributed to all readers for final approval.

The EULAR-OMERACT rheumatoid arthritis MRI reference image atlas: the wrist joint

This paper presents the wrist joint MR images of the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas. Reference images for scoring synovitis, bone oedema, and bone erosions according to the OMERACT RA MRI scoring (RAMRIS) system are provided. All grades (0-3) of synovitis are illustrated in each of the three wrist joint areas defined in the scoring system--that is, the distal radioulnar joint, the radiocarpal joint, and the intercarpal-carpometacarpal joints. For reasons of feasibility, examples of bone abnormalities are limited to five selected bones: the radius, scaphoid, lunate, capitate, and a metacarpal base. In these bones, grades 0-3 of bone oedema are illustrated, and for bone erosion, grades 0-3 and examples of higher grades are presented. The presented reference images can be used to guide scoring of wrist joints according to the OMERACT RA MRI scoring system.

Level of agreement and biopsy correlation using two- and three-tier systems to grade cervical dyskaryosis

At present, a three-tier system is used to grade cervical dyskaryosis in the UK, although the two-tier Bethesda system is used in the United States, and the British Society for Clinical Cytology has recommended that a two-tier system be implemented here. In this study, we have retrospectively re-graded 117 conventional cervical smears using both systems to determine the intra- and interobserver variation and compare the cytology grading in both systems with the final histology. The intra and interobserver agreement was moderate using both grading systems, but the agreement between cytology grade and final histology was poor in both the two- and three-tier systems, and slightly worse using two-tier grading. However, when each of the three histological categories is considered separately the two-tier system appears to work better. Therefore, changing the way in which cervical dyskaryosis is graded in the UK may result in poorer agreement between the cervical smear result and the final histological diagnosis if introduced without proper training, monitoring and assessment.

Detection of erosions in the rheumatoid hand; a comparative study of multidetector computerized tomography versus magnetic resonance scanning

OBJECTIVE

To compare the detection and scoring of erosions in patients with rheumatoid arthritis (RA) using magnetic resonance (MR) and multidetector helical computerized tomographic (CT) scanning.

METHODS

Comparative CT and MR scans of the dominant wrist were obtained from 9 patients with RA and clinical examination was performed to assess disease activity. MR and CT scans were scored for erosions and MR scans for bone edema by 2 radiologists using a validated system. Radiographs of the hands and feet were also scored for erosions using the modified Sharp score.

RESULTS

In 117 of 135 (87%) sites there was concordance for erosions between MR and CT scans. At the remaining 18/135 sites (13%), erosions were identified by CT but not MR in 12/135 (9%) and by MR but not CT in 6/135 (4%). Partial volume artefacts on MR images and shifts in slice position were the most common reasons for erosion mismatch between MR and CT. The mean CT bone erosion score was significantly higher than the MR erosion score when individual bony sites were examined (p = 0.024), with the greatest difference being at the metacarpal bases. The total bone erosion score also tended to be higher on CT than MR [median scores of 20 (range 0-66) and 12 (0-51), respectively; p = 0.060]. MR and CT erosion scores correlated strongly with the total Sharp score (r = 0.93, p = 0.0002 and r = 0.94, p = 0.0002, respectively) and with the Disease Activity Score (MR: r = 0.77, p = 0.02; CT: r = 0.71, p = 0.03).

CONCLUSION

Most erosions were detected using both modalities, but erosion scores were higher on CT than MR scans, especially at the metacarpal bases. It is possible that small erosions in some regions are more easily detected by CT because of its ability to clearly delineate cortical bony margins.