Ultrasound in rheumatoid arthritis

The Clinical Utility of Musculoskeletal Ultrasound for Disease Activity Evaluation and Therapeutic Response Prediction in Rheumatoid Arthritis Patients: A Narrative Review

Rheumatoid arthritis (RA) is characterized by persistent synovitis and joint/bone destruction. There is an unmet need to predict the therapeutic response to disease-modifying anti-rheumatic drugs (DMARDs) and achieve a treat-to-target goal. Musculoskeletal ultrasound (MSUS) is widely used to identify structural change and assess therapeutic response in RA. This review aims to summarize the available evidence regarding the clinical application of MSUS in evaluating disease activity and predicting therapeutic responses to DMARDs. We searched the MEDLINE database using the PubMed interface and reviewed English-language literature from 2000 to 2022. This review focuses on the updated role of MSUS in assessing disease activity and predicting therapeutic responses to DMARDs in RA patients. MSUS is now widely applied to identify articular structural change and assess the disease activity of RA. Combined use of gray scale and power Doppler MSUS is also superior to clinical assessment and laboratory examination in evaluating disease activity of RA. With portable use, good viability, and high sensitivity to articular inflammation, MSUS would be useful in assessing therapeutic response to biologic/targeted synthetic DMARDs (b/tsDMARDs) in RA patients. Given MSUS could also detect subclinical inflammation in a substantial proportion of RA patients with clinical remission, it is recommended to assess b/tsDMARDs-treated RA patients who have achieved low disease activity or remission. Although substantial literature data have revealed clinical utility of MSUS for monitoring disease activity and evaluating therapeutic response in RA patients, the evidence regarding its predictive value for the effectiveness of b/tsDMARDs is limited.

hIgD-Fc-Ig fusion protein regulates T cell functions by inhibiting TCR signaling pathway in adjuvant arthritis rats

This study aimed to investigate the effect of hIgD-Fc-Ig on TCR-Lck-Erk activated by IgD in adjuvant arthritis (AA) rats. Wistar rats were divided into the normal, AA model, hIgD-Fc-Ig (1 mg/kg, 3 mg/kg and 9 mg/kg) and Etanercept (3 mg/kg) groups. The overall index of AA rats was measured every 3 days. The pathologic examination of knee joints and the proliferation of the spleen and thymus of AA rats were detected by H&E staining and CCK-8. The blood flow signal of knee joints of experimental rats was examined by US. The articular bone injury was detected by X-ray. The changes in PBMCs and spleen T cell subsets were detected by flow cytometry. The expression of CD3ε, p-Lck, p-Zap70, Ras, and p-Erk in rat spleens was detected by immunofluorescence and WB. Rat spleen T cells or Jurkat cells treated by IgD to observe the effect of hIgD-Fc-Ig on TCR and its downstream protein expression. The results showed that hIgD-Fc-Ig had a therapeutic effect on AA rats by reducing the secondary inflammation, improving pathological changes. hIgD-Fc-Ig can reduce the ratio of Th cells of PBMCs of AA rats, the ratio of Th, Th1, Th17 cells and increase the ratio of Th2, Treg cells of AA rat spleens. hIgD-Fc-Ig could down-regulate the expression of CD3ε, p-Lck, p-Zap70, Ras, p-Erk in vivo or in vitro. In conclusion, hIgD-Fc-Ig could alleviate the symptoms of AA rats and regulate T cells through TCR-Lck-Erk signaling pathway and maybe a new promising biological agent for RA.

Comparison and correlation study of synovial ultrasound indices and serum VEGF in rheumatoid wrist arthritis before and after treatment

OBJECTIVE

Rheumatoid wrist arthritis is a chronic autoimmune disease, resulting in joint deformity and functional impairment. We aimed to compare the wrist synovial ultrasound indices and serum vascular endothelial growth factor (VEGF) level in patients with RA before and after treatment, and to explore the correlation between the two.

METHODS

Forty patients with RA in wrist underwent ultrasound examination to determine wrist synovial thickness, synovial blood flow grade, and synovial artery resistive index (RI) before and after treatment. The serum level of VEGF was detected by enzyme-linked immunosorbent assay. Correlation between synovial ultrasound indices and serum VEGF level was assessed.

RESULTS

Pre-treatment synovial thickness, synovial artery RI, and serum VEGF level were 8.60 ± 2.82 mm, 0.62 ± 0.07, and 419.49 ± 19.27 pg/mL, respectively. The corresponding post-treatment levels were 4.05 ± 1.89 mm, 0.83 ± 0.10, and 199.30 ± 16.18 pg/mL. Pre-treatment distribution of synovial blood flow grades was as follows: grade 0, nil; grade I, 1 case; grade II, 17 cases; grade III, 22 cases. The post-treatment distribution was as follows: grade 0, 6 cases; grade I, 23 cases; grade II, 11 cases; and grade III, nil. There were significant differences between pre- and post-treatment wrist synovial thickness, artery RI, and blood flow grading. Wrist synovial thickness and synovial blood flow grade showed a strong positive correlation with serum VEGF level (P < 0.01). There was strong negative correlation between wrist synovial artery RI and serum VEGF level (P < 0.01).

CONCLUSION

The strong correlation between wrist synovial ultrasound indicators and serum VEGF may be clinically useful for diagnosis and therapy.

Unusual, but important, peri- and extra-articular manifestations of rheumatoid arthritis: a pictorial essay

Ultrasonography is a useful technique to detect soft tissue changes of rheumatoid arthritisnot only synovitis, but also tenosynovitis, bursitis, and enthesitis-even at a subclinical stage. However, radiologists tend to focus on synovitis in daily practice, and unusual peri- or extra-articular manifestations of rheumatoid arthritis are difficult to detect at the initial presentation. This pictorial essay describes a broad spectrum of ultrasonographic findings in tendons, bursae, ligaments, subcutaneous tissues, bones, and nerves to assist in the accurate diagnosis of rheumatoid arthritis.

T2 Mapping as a New Method for Quantitative Assessment of Cartilage Damage in Rheumatoid Arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is associated with damage of the articular cartilage and the periarticular bone. While imaging of bone damage has substantially improved in recent years, direct imaging of the articular cartilage of the hand joints in patients with RA is still challenging. The study used T2 mapping of the finger joints to assess cartilage damage in RA.

METHODS

Magnetic resonance imaging (MRI) at 3 Tesla was done in 30 patients with RA, and T2 relaxation times visualizing alteration in the collagen network and hydration of articular cartilage were mapped in 6 cartilage regions of the metacarpophalangeal (MCP) joints 2 and 3. Values were related to autoantibody status [anticitrullinated protein antibodies (ACPA), rheumatoid factor (RF)], disease duration, and disease activity as well as sex and age of the patients.

RESULTS

T2 relaxation times could be reliably measured in the 6 regions of the MCP joints. Significantly higher relaxation times indicating more advanced cartilage alterations were observed in the metacarpal heads of ACPA-positive (p = 0.001-0.010) and RF-positive patients (p = 0.013-0.025) as well as those with longer disease duration (> 3 yrs; p = 0.028-0.043). Current disease activity, sex, and age did not influence T2 relaxation times.

CONCLUSION

These data show that cartilage damage can be localized and quantified in the hand joints of patients with RA by T2 mapping. Further, ACPA and RF positivity as well as disease duration appear to be the crucial factors influencing cartilage damage.

Validity of 7-Joint Versus Simplified 12-Joint Ultrasonography Scoring Systems in Assessment of Rheumatoid Arthritis Activity

INTRODUCTION

Musculoskeletal ultrasonography (US) is an objective tool for the evaluation of disease activity in rheumatoid arthritis (RA) patients. There is no consensus on the exact number of joints that should be examined. Examination of reduced joint count is more practical than the comprehensive one.

OBJECTIVES

This is a cross-sectional study investigated the validity of a 7-joint US score (US7) in assessment of joint inflammation in RA patients compared with a simplified 12-joint US score (US12) and correlated both to composite disease activity indices.

METHODS

The activity status of 50 RA patients was assessed clinically and ultrasonographically. The disease activity was calculated using 3 composite indices. Ultrasonography was performed by 1 blinded rheumatologist, using power Doppler (PD) and gray-scale (GS) US examination. The US7 and simplified US12 were performed as originally described. However, the GS synovitis and PD synovitis of US12 were computed in 2 separate scores instead of 1. Two sum US7 scores were added, sum (GS) US7 and sum (PD) US7 after summating synovitis and tenosynovitis scores. Ultrasonography interobserver/intraobserver reliability was evaluated on 40 stored images.

RESULTS

Correlation coefficient between the different ultrasonographic scores showed no difference. The GS scores showed no correlation with disease activity parameters; however, the PD scores did. The sum (PD) US7 was the only score that showed significant correlation with the 3 different composite disease indices.

CONCLUSIONS

All studied US scores proved valid in assessment of disease activity status in RA. This is in favor of using the less-time-consuming US7 scores. The strongest correlation found with sum (PD) US7 confirmed the importance of incorporating the tendon in the disease activity assessment.

In vivo imaging of early stages of rheumatoid arthritis by α5β1-integrin-targeted positron emission tomography

Background

Rheumatoid arthritis (RA) is one of the most common rheumatic diseases. Joint inflammation and pathological growth of joint cartilage cause swollen and painful joints, which severely diminishes the patients’ life quality. There is no causal treatment. Symptomatic therapies should start as early as possible to take maximal effect. Hence, diagnostic procedures capable of detecting affected joints before the onset of clinical symptoms are highly desirable. We explored the value of PET imaging of integrin subtypes αvβ3 and α5β1 for early detection of RA foci in collagen-induced arthritis (CIA) mouse models.

Results

Development of RA in CIA mice was monitored by paw scoring, and αvβ3- and α5β1-integrin expression was quantified by μPET using ⁶⁸Ga-Avebetrin and ⁶⁸Ga-Aquibeprin. For consecutive sections of selected decalcified joints (knee, ankle), arthritic degeneration and integrin expression were assessed by MOVAT staining and β3/α5 immunohistochemistry (IHC), respectively. β3- and α5-IHC revealed elevated levels of both αvβ3- and α5β1-integrin in arthritic joints. Unlike αvβ3, α5β1 is strongly expressed in the proliferating synovial lining layer, which suggests that its presence is directly related to RA development. For mice with advanced RA (6 weeks after CIA), PET signals for α5β1-integrin were substantially stronger (> 300% of baseline) than that of αvβ3-integrin (< 200%). A longitudinal PET follow-up revealed that the manifestation of clinical symptoms of RA is preceded by upregulation of α5β1- but not of αvβ3-integrin.

Conclusion

α5β1-integrin PET could add a new functional imaging aspect to the portfolio of RA diagnostics because it appears to be a sensitive biomarker for early RA development. We suggest α5β1-integrin PET as a valuable tool to achieve a higher precision for early diagnosis of RA, including initial staging, monitoring of the disease course, and drug treatment, and for planning of radiosynoviorthesis (RSO).

[Update cartilage imaging of the small joints : Focus on high-field MRI]

BACKGROUND

Cartilage imaging of small joints is increasingly of interest, as early detection of cartilage damage may be relevant regarding individualized surgical therapies and long-term outcomes.

PURPOSE

The aim of this review is to explain modern cartilage imaging of small joints with emphasis on MRI and to discuss the role of methods such as CT arthrography as well as compositional and high-field MRI.

MATERIALS AND METHODS

A PubMed literature search was performed for the years 2008-2018.

RESULTS

Clinically relevant cartilage imaging to detect chondral damage in small joints remains challenging. Conventional MRI at 3 T can still be considered as a reference for cartilage imaging in clinical routine. In terms of sensitivity, MR arthrography (MR-A) and computed tomography arthrography (CT-A) are superior to non-arthrographic MRI at 1.5 T in the detection of chondral damage. Advanced degenerative changes of the fingers and toes are usually sufficiently characterized by conventional radiography. MRI at field strengths of 3 T and ultrahigh-field imaging at 7 T can provide additional quantifiable, functional and metabolic information.

CONCLUSION

Standardized cartilage imaging plays an important role in clinical diagnostics in the ankle joint due to the availability of different and individualized therapeutic concepts. In contrast, cartilage imaging of other small joints as commonly performed in clinical studies has not yet become standard of care in daily clinical routine. Although individual study results are promising, additional studies with large patient collectives are needed to validate these techniques. With rapid development of new treatment concepts radiological diagnostics will play a more significant role in the diagnosis of cartilage lesions of small joints.

Utility of Transfacial Dental Ultrasonography in Evaluation of Cystic Jaw Lesions

OBJECTIVES

Plain radiography has been widely used in dentistry. Because of the variability of the quality of equipment, radiographic technique, accuracy of interpretation, and radiation risk to the patients, the field is ripe for the introduction of other newer diagnostic modalities. In this report, we demonstrate the utility of ultrasonography in the diagnostic workup of cystic or cystlike lesions of the jaw.

METHODS

We used a transfacial ultrasonographic scanning approach to examine 32 patients with clinical or radiographic presentation of a jaw cyst. Computed tomography and histopathologic analysis were used as the reference standards to confirm the findings.

RESULTS

Ultrasonography could establish the presence or absence of a lesion, erosion of the buccal cortical plate, and identification of associated soft tissue involvement in all cases (sensitivity and specificity, 100% and 100%, respectively; area under the receiver operating characteristic curve, 1.0; P < .001).

CONCLUSIONS

Our observations revealed the usefulness of ultrasonography and demonstrated its potential value when introduced as a routine office-based imaging method for dentistry.

Diagnostic value of high-frequency color Doppler ultrasonography examination in combination with anti-cyclic citrullinated peptide antibody testing in rheumatoid arthritis patients

We studied the diagnostic value of high-frequency color Doppler ultrasonography (HCDU) examination in combination with anti-cyclic citrullinated peptide (anti-CCP) antibody testing in rheumatoid arthritis (RA) patients with finger joint damage. From January 2015 to December 2015, 80 patients diagnosed with RA with finger joints damage were enrolled in this study. Patients were examined with HCDU. Serum anti-CCP antibody level was tested using ELISA, and results were compared with the healthy control group. Results obtained by ELISA demonstrated that the positive rate of anti-CCP antibodies was 73.8% in the study group, and 10% in the control group. The negative rate was 26.2% in the study group, and 90% in the control group. HCDU examination suggested that the predominantly affected joint by bone erosion of RA with finger joint damage was MCP3 (16.7%), followed by PIP3 (14.1%), MCP2 (13.5%) and PIP2 (12.8%). The slightest affected joint was thumb metacarpophalangeal joint, followed by thumb, little finger metacarpophalangeal joint and proximal interphalangeal joint. The sensitivity of diagnosis of RA with finger joints damage with both HCDU and CCP antibody examination showed a significantly lower level compared with examination with each one of the methods alone, while specificity showed a significantly higher level. Thus, a combination of HCDU examination and anti-CCP antibody testing can be considered useful to improve the early diagnostic rate of RA. HCDU examination is a sensitive, secure, atraumatic and easily-operated diagnostic method for early RA patients with finger joint damage. When combined with anti-CCP antibody testing, it will provide a better chance for RA patients, and give them hope for a better treatment and improved prognosis.

Gray-scale and color duplex Doppler ultrasound of hand joints in the evaluation of disease activity and treatment in rheumatoid arthritis

AIM

To evaluate the role of gray-scale and color duplex-Doppler ultrasound (CDUS) in diagnosis of changes of hand joints and assessment of treatment efficacy in patients with rheumatoid arthritis (RA) by comparing qualitative and quantitative US parameters with clinical and laboratory indicators of disease activity.

METHODS

Ulnocarpal (UC), metacarpophalangeal (MCP), and proximal interphalangeal (PIP) joints in 30 patients with RA were examined by gray-scale and CDUS before and after six months of treatment. Morphologic and quantitative Doppler findings (synovial thickness, effusion quantity, vascularization degree, resistance index, velocities) were compared with clinical indicators of disease progression: disease activity score (DAS 28), Health Assessment Questionnaire (HAQ), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C reactive protein (CRP).

RESULTS

Clinical indicators changed significantly after treatment: ESR from 38.1±22.4 mm/h to 27.8±20.9 mm/h (P=0.013), DAS 28 from 5.47±1.56 to 3.87±1.65 (P<0.001), and HAQ from 1.26±0.66 to 0.92±0.74 (P=0.030), indicating therapeutic effectiveness. In all MCP and UC joints we observed a significant change in at least one US parameter, in 6 out of 12 joints we observed a significant change in ≥2 parameters, and in 2 UC joints we observed significant changes in ≥3 parameters. The new finding was that the cut-off values of resistance index of 0.40 at baseline and of 0.55 after the treatment indicated the presence of active disease and the efficacy of treatment, respectively; also it was noticed that PIP joints can be omitted from examination protocol.

CONCLUSION

Gray scale and CDUS are useful in diagnosis of changes in UC and MCP joints of patients with RA and in monitoring the treatment efficacy.

Power Doppler ultrasound monitoring of response to anti-tumour necrosis factor alpha treatment in patients with rheumatoid arthritis

OBJECTIVES

To monitor by power Doppler US (PDUS) the short-term response to anti-TNFα therapy in six target joints of RA patients; to correlate PDUS findings with clinical assessments and laboratory indices of disease activity.

METHODS

Consecutive RA patients starting anti-TNFα therapy were included and studied at baseline and 3 months later. Clinical (number of tender joints; number of swollen joints; Visual Analogue Scale; DAS28) and laboratory (ESR and CRP) assessments were performed. All patients were evaluated by PDUS at six target joints (II MCP, wrist, knee bilaterally). The components of synovitis (synovial hypertrophy, joint effusion, and power Doppler) were analysed and graded (0-3 semi-quantitative score). Moreover, by summing the PDUS findings, three different scores were calculated: a single inflammatory lesion score (0-18, for synovial hypertrophy, effusion, power Doppler), a joint score (0-18; at II MCP, wrist and knee joints) and a global score (0-54; sum of all abnormalities).

RESULTS

Sixty-eight RA patients were studied. A significant decrease in the joint score in all articular sites (MCP, P = 0.003; knee, P = 0.002; wrist, P = 0.0001) as well as in the scores of the single components of synovitis (P = 0.0001-0.002) and in the global 6-joint score (P = 0.0001) was found. All clinical and laboratory parameters were significantly decreased at follow-up (P = 0.0001-0.001). A moderate significant positive correlation was observed between the global PDUS score and DAS28 (r = 0.38; P = 0.001).

CONCLUSION

PDUS is a sensitive-to-change imaging modality for monitoring the short-term response to anti-TNFα treatment in RA patients. The assessment of a limited number of joints makes the evaluation feasible in rheumatology practice as a complementary tool to clinical assessment.

[Morphological and functional cartilage imaging]

Excellent morphological imaging of cartilage is now possible and allows the detection of subtle cartilage pathologies. Besides the standard 2D sequences, a multitude of 3D sequences are available for high-resolution cartilage imaging. The first part therefore deals with modern possibilities of morphological imaging. The second part deals with functional cartilage imaging with which it is possible to detect changes in cartilage composition and thus early osteoarthritis as well as to monitor biochemical changes after therapeutic interventions. Validated techniques such as delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T2 mapping as well the latest techniques, such as the glycosaminoglycan chemical exchange-dependent saturation transfer (gagCEST) technique will be discussed.