Reliability assessment of the definition of ultrasound enthesitis in SpA: results of a large, multicentre, international, web-based study.

OBJECTIVES: To investigate the reliability of the OMERACT US Task Force definition of US enthesitis in SpA. METHODS: In this web exercise, based on the evaluation of 101 images and 39 clips of the main entheses of the lower limbs, the elementary components included in the OMERACT definition of US enthesitis in SpA (hypoechoic areas, entheseal thickening, power Doppler signal at the enthesis, enthesophytes/calcifications, bone erosions) were assessed by 47 rheumatologists from 37 rheumatology centres in 15 countries. Inter- and intra-observer reliability of the US components of enthesitis was calculated using Light's kappa, Cohen's kappa, Prevalence And Bias Adjusted Kappa (PABAK) and their 95% CIs. RESULTS: Bone erosions and power Doppler signal at the enthesis showed the highest overall inter-reliability [Light's kappa: 0.77 (0.76-0.78), 0.72 (0.71-0.73), respectively; PABAK: 0.86 (0.86-0.87), 0.73 (0.73-0.74), respectively], followed by enthesophytes/calcifications [Light's kappa: 0.65 (0.64-0.65), PABAK: 0.67 (0.67-0.68)]. This was moderate for entheseal thickening [Light's kappa: 0.41 (0.41-0.42), PABAK: 0.41 (0.40-0.42)], and fair for hypoechoic areas [Light's kappa: 0.37 (0.36-0.38); PABAK: 0.37 (0.37-0.38)]. A similar trend was observed in the intra-reliability exercise, although this was characterized by an overall higher degree of reliability for all US elementary components compared with the inter-observer evaluation. CONCLUSIONS: The results of this multicentre, international, web-based study show a good reliability of the OMERACT US definition of bone erosions, power Doppler signal at the enthesis and enthesophytes/calcifications. The low reliability of entheseal thickening and hypoechoic areas raises questions about the opportunity to revise the definition of these two major components for the US diagnosis of enthesitis.

Reliability assessment of ultrasound muscle echogenicity in patients with rheumatic diseases: Results of a multicenter international web-based study.

Objectives: To investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases. Methods: Forty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0-3) and a continuous quantitative measurement ("VAS echogenicity," 0-100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall's Tau and Pearson's Rho coefficients. Results: The semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57-0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68-0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. "VAS echogenicity" showed a high reliability both in the inter-observer [ICC = 0.80 (0.75-0.85)] and intra-observer [ICC = 0.88 (0.88-0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and "VAS echogenicity" [ICC = 0.52 (0.50-0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively). Conclusion: The results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases.

An ultrasound automated method for non-invasive assessment of carotid artery pulse wave velocity.

To validate the clinical applicability and feasibility of an automated ultrasound (US) method in measuring the arterial stiffness of patients with chronic inflammatory rheumatic diseases, comparing automated measurements performed by a rheumatologist without experience in vascular sonography with those obtained by a sonographer experienced in vascular US, using a standardized manual method. Twenty subjects affected by different chronic inflammatory rheumatic disorders were consecutively recruited. For each patient, the arterial stiffness of both common carotids was manually calculated. Subsequently, the measure of the pulse wave velocity (PWV) was obtained using an US device called Radio Frequency - Quality Arterial Stiffness (RF-QAS), provided by the same US system (ie, My Lab 70 XVG, Esaote SpA, Genoa, Italy) equipped with a 4-13 MHz linear probe. The reliability comparison between the two US methods was calculated using the intraclass correlation coefficient (ICC). ICC between the values obtained with the two methods for calculating the arterial stiffness resulted 0.789. A significant positive correlation between the two methods was also established with Pearson's (r=0.62, p<0.0001) and Spearman's analysis (r=0.66, p=0.001). A significant performance comparison was seen using Bland-Altman plot. The acquisition of the arterial stiffness parameter with the automated method required about 2 min for each patient. Clinical applicability of this US automated method to assess PWV at common carotid level by a rheumatologist is reliable and feasible in comparison with a conventional manual method.

Ultrasound imaging for the rheumatologist XL. Sonographic assessment of the hip in rheumatoid arthritis patients.

OBJECTIVES: The aim of the present study was to correlate clinical and laboratory data with those obtained by ultrasound (US) evaluation of the hip in a cohort of patients with rheumatoid arthritis (RA). METHODS: Fifty-two RA patients attending the Rheumatology Departments involved in the present study were enrolled. Demographic (age, gender), clinical (body mass index, disease duration, treatments, history or current hip pain, tenderness by internal or external hip rotation or palpation of the greater trochanteric region), laboratory (erythrosedimentation rate, C-reactive protein, rheumatoid factor and antibodies anti-citrullinated peptides) and clinimetric data (disease activity score 28 - DAS28, Health Assessment Questionnaire - HAQ, Lequesne index) were collected. All patients underwent an US examination of both hips according to international guidelines. RESULTS: A total of 100 hips were scanned in 52 patients with RA. Approximately half of the patients reported a history of hip pain, one fourth complained of current pain, and the physical examination (internal and/or external rotation and palpation of the greater trochanteric region) evocated pain up to 19% and 22% of the patients, respectively. US examination found signs of hip joint abnormalities in 42% of the patients; US changes indicative of hip joint inflammation and damage were detected respectively in 24% and 32% of the cases. No patient presented power Doppler signal in the hip joint. A significant correlation between US pathological findings at hip level was found with clinical data (current pain and evocated pain by internal or external hip rotation). Furthermore, US cartilage lesion correlated with age of the patient, and US bone erosions with the disease duration. No correlation was found between the sonographic assessment and laboratory data, DAS 28, and Lequesne index. CONCLUSIONS: US abnormalities at hip joint level obtained in the present study correlated with clinical findings, while no correlation was found with DAS28 or laboratory data. Further investigations are encouraged to clarify the US additional value at hip level in patients with RA.

Comparison between conventional and automated software-guided ultrasound assessment of bilateral common carotids intima-media thickness in patients with rheumatic diseases.

Over the last decade, a growing number of studies have been published supporting the high prevalence of atherosclerosis in rheumatic patients with chronic inflammatory diseases. Ultrasound (US) represents the imaging technique of choice for revealing early atherosclerotic changes at carotids level. New US software, mainly developed to rectify its operator dependence, requires a comparison with conventional technique. The main aim of the present study was to compare conventional and software-guided US in the assessment of intima-media thickness (IMT) of common carotids. Thirty-two consecutive patients with chronic inflammatory rheumatic conditions, presenting at the outpatient clinics of the Rheumatology Department--Università Politecnica delle Marche, Italy--were enrolled in the present study. The patients underwent a US assessment of the IMT of the posterior wall of common carotids using a My Lab 70 XVG system (Esaote SpA, Genoa, Italy) equipped with a 4-13 MHz linear probe. The US examinations were performed by two sonographers. One of them used the conventional manual approach and the second sonographer adopted a software-guided technique (named RF-QIMT technology). Inter-observer reliability was determined using intra-class correlation coefficient (ICC) and the Bland-Altman plot. Agreement between the two methods was high with ICC value of 0.74 (0.69 and 0.77 for the right and left common carotid, respectively). The Bland-Altman plot showed minimal proportional error and high limits of agreement. Substantial inter-observer agreement rates for the assessment of the IMT were achieved. Further studies are encouraged to confirm these results in a larger cohort of patients.

Inter-observer reliability of high-resolution ultrasonography in the assessment of bone erosions in patients with rheumatoid arthritis: experience of an intensive dedicated training programme.

OBJECTIVE: The present study was aimed at testing the ability of a rheumatologist without experience in ultrasound (US) who attended an intensive 4-week training programme focused on US assessing bone erosions in the hands and feet in patients with RA. METHODS: Twenty patients diagnosed with RA according to the ACR criteria were included in the study. All US examinations were performed bilaterally by two investigators (with different experience in the field of musculoskeletal US) at the following sites: the dorsal, lateral and volar aspect of the second metacarpal, ulnar and fifth metatarsal head; and the dorsal and volar aspect of the third metacarpal and second proximal heads. Each quadrant was scanning in longitudinal and transverse scans for assessing the qualitative, semiquantitative and quantitative US findings indicative of bone erosions according the OMERACT preliminary definition. RESULTS: Both κ-values and overall agreement percentages of qualitative and semiquantitative assessments showed moderate to excellent agreement between the two investigators. Similar results were obtained for the quantitative assessment with the concordance correlation coefficient value always significant. The only exception was the volar aspects, in particular those of the fifth metatarsal head. CONCLUSION: Our study suggests that after a 4-week dedicated training programme, a rheumatologist without experience in US is able to detect and score bone erosions in the hands and feet of patients with RA.

Interobserver reliability of ultrasonography in the assessment of cartilage damage in rheumatoid arthritis.

OBJECTIVES: To evaluate the interobserver reliability of ultrasonography (US) in the assessment of cartilage damage at metacarpophalangeal (MCP) joint level in patients with rheumatoid arthritis (RA). METHODS: US examinations were performed on 80 MCP joints of 20 patients with RA using a MyLab70 XVG (Esaote Biomedica, Genoa, Italy), equipped with a broadband linear probe (6-18 MHz). For each patient, second and third MCP joints of both hands were examined independently on the same day by two rheumatologists (an experienced musculoskeletal sonographer and an investigator with limited US training). A multiplanar scanning technique on dorsal, lateral and volar aspects of the MCP joints was adopted. All US pathological findings were documented on at least two perpendicular scanning planes. Each joint was assessed by quadrant for the presence or absence of cartilage damage. Cartilage damage was also scored per quadrant on a five-grade semiquantitative scoring system on which investigators reached a consensus prior to the study. RESULTS: Exact agreement between investigators was found in 173 out of 200 quadrants (86.5%) with regard to presence or absence of cartilage damage. Percentages of exact agreement for cartilage damage semiquantitative assessment at dorsal, lateral and volar quadrants were 72.5%, 52.5% and 85%, respectively, while unweighted κ values were 0.561, 0.366 and 0.766, respectively. CONCLUSIONS: The present study demonstrated moderate to good interobserver reproducibility of a semiquantitative scoring system based on qualitative morphological changes for cartilage damage at MCP joint level in patients with RA.