Standardization of interstitial lung disease assessment by ultrasound: results from a Delphi process and web-reliability exercise by the OMERACT ultrasound working group.

OBJECTIVES: Over the last years ultrasound has shown to be an important tool for evaluating lung involvement, including interstitial lung disease (ILD) a potentially severe systemic involvement in many rheumatic and musculoskeletal diseases (RMD). Despite the potential sensitivity of the technique the actual use is hampered by the lack of consensual definitions of elementary lesions to be assessed and of the scanning protocol to apply. Within the Outcome Measures in Rheumatology (OMERACT) Ultrasound Working Group we aimed at developing consensus-based definitions for ultrasound detected ILD findings in RMDs and assessing their reliability in dynamic images. METHODS: Based on the results from a systematic literature review, several findings were identified for defining the presence of ILD by ultrasound (i.e., Am-lines, B-lines, pleural cysts and pleural line irregularity). Therefore, a Delphi survey was conducted among 23 experts in sonography to agree on which findings should be included and on their definitions. Subsequently, a web-reliability exercise was performed to test the reliability of the agreed definitions on video-clips, by using kappa statistics. RESULTS: After three rounds of Delphi an agreement >75 % was obtained to include and define B-lines and pleural line irregularity as elementary lesions to assess. The reliability in the web-based exercise, consisting of 80 video-clips (30 for pleural line irregularity, 50 for B-lines), showed moderate inter-reader reliability for both B-lines (kappa = 0.51) and pleural line irregularity (kappa = 0.58), while intra-reader reliability was good for both B-lines (kappa = 0.72) and pleural line irregularity (kappa = 0.75). CONCLUSION: Consensus-based ultrasound definitions for B-lines and pleural line irregularity were obtained, with moderate to good reliability to detect these lesions using video-clips. The next step will be testing the reliability in patients with ILD linked to RMDs and to propose a consensual and standardized protocol to scan such patients.

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.

Video clip assessment of a salivary gland ultrasound scoring system in Sjögren's syndrome using consensual definitions: an OMERACT ultrasound working group reliability exercise.

OBJECTIVE: To develop ultrasound (US) definitions and a US novel scoring system for major salivary gland (SG) lesions in patients with primary Sjögren's syndrome (pSS) and to test their intrareader and inter-reader reliability using US video clips. METHODS: Twenty-five rheumatologists were subjected to a three-round, web-based Delphi process in order to agree on (1) definitions and scanning procedure of salivary gland ultrasonography (SGUS): parotid, submandibular and sublingual glands (PG, SMG and SLG); (2) definitions for the elementary SGUS lesions in patients with Sjögren's syndrome; (3) scoring system for grading changes. The experts rated the statements on a 1-5 Likert scale. In the second step, SGUS video clips of patients with pSS and non-pSS sicca cases were collected containing various spectrums of disease severity followed by an intrareader and inter-reader reliability exercise. Each video clip was evaluated according to the agreed definitions. RESULTS: Consensual definitions were developed after three Delphi rounds. Among the three selected SGs, US assessment of PGs and SMGs was agreed on. Agreement was reached to score only greyscale lesions and to focus on anechoic/hypoechoic foci in a semiquantitative matter or, if not possible on a qualitatively (present/absent) evaluation of fatty or fibrous lesions. Intrareader reliability for detecting and scoring these lesions was excellent (Cohen's kappa 0.81) and inter-reader reliability was good (Light's kappa 0.66). CONCLUSION: New definitions for developing a novel semiquantitative US score in patients with pSS were developed and tested on video clips. Inter-reader and intrareader reliabilities were good and excellent, respectively.

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.