Power Doppler sonography and pulse-inversion harmonic imaging in evaluation of rheumatoid arthritis synovitis

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.

Contrast-enhanced ultrasound for musculoskeletal indications in children

The increasing use of contrast-enhanced ultrasound (CEUS) has opened exciting new frontiers for musculoskeletal applications in adults and children. The most common musculoskeletal-related CEUS applications in adults are for detecting inflammatory joint diseases, imaging skeletal muscles and tendon perfusion, imaging postoperative viability of osseous and osseocutaneous tissue flaps, and evaluating the malignant potential of soft-tissue masses. Pediatric musculoskeletal-related CEUS has been applied for imaging juvenile idiopathic arthritis and Legg-Calvé-Perthes disease and for evaluating femoral head perfusion following surgical hip reduction in children with developmental hip dysplasia. CEUS can improve visualization of the capillary network in superficial and deep tissues and also in states of slow- or low-volume blood flow. In addition, measurements of blood flow imaging parameters performed by quantitative CEUS are valuable when monitoring the outcome of treatment interventions. In this review article we present current experience regarding a wide range of CEUS applications in musculoskeletal conditions in adults and children, with emphasis on the latter, and discuss imaging techniques and CEUS findings in musculoskeletal applications.

Contrast-Enhanced Ultrasound for Musculoskeletal Applications: A World Federation for Ultrasound in Medicine and Biology Position Paper

This World Federation for Ultrasound in Medicine and Biology position paper reviews the diagnostic potential of ultrasound contrast agents for clinical decision-making and provides general advice for optimal contrast-enhanced ultrasound performance in musculoskeletal issues. In this domain, contrast-enhanced ultrasound performance has increasingly been investigated with promising results, but still lacks everyday clinical application and standardized techniques; therefore, experts summarized current knowledge according to published evidence and best personal experience. The goal was to intensify and standardize the use and administration of ultrasound contrast agents to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients.

[CEUS-application possibilities in the musculoskeletal system]

METHODICAL ISSUE

Contrast-enhanced ultrasound (CEUS) offers easily accessible visualization and quantification of the skeletal muscle microcirculation and other tissues in vivo and in real-time with almost no side effects.

AIM

The aim of this review is to present the increasing number of musculoskeletal CEUS applications.

METHODICAL INNOVATIONS/PERFORMANCE

CEUS applications regarding the musculoskeletal system include applications at bone and joints extending beyond the visualization of only the muscular microcirculation. Besides basic muscle physiology, impaired microcirculation in patients with peripheral artery disease or diabetes mellitus and the diagnosis of inflammatory myopathies have been the subject of previous CEUS studies. More recent studies in orthopedics and traumatology have focused on osseous and muscular perfusion characteristics, e. g., in differentiating infected and aseptic non-unions or the impact of different types of implants and prostheses on muscular microcirculation as a surrogate marker of clinical success.

PRACTICAL RECOMMENDATIONS

CEUS of the musculoskeletal system is used in clinical trials or off-label. Therefore, it is not well established in clinical routine. However, considering the increasing number of musculoskeletal CEUS applications, this could change in the future.

Anti-CCP status determines the power Doppler oscillation pattern in rheumatoid arthritis: a prospective study

Rheumatoid arthritis (RA) is a chronic inflammatory disease leading to joint destruction. Serologically, it can be differentiated according to rheumatoid factor (RF), anti-cyclic citrullinated peptide antibodies (anti-CCP), or both. This differentiation is prognostically and therapeutically relevant. No method has been described to separate the two forms phenotypically. We hypothesize that a differentiation is possible by evaluating oscillation patterns in power Doppler sonography (PDS). In a prospective study, 20 patients with anti-CCP-positive RA and 20 patients with anti-CCP-negative RA with active wrist synovitis were examined. A PDS scan was performed, and perfusion maxima (P _max) and minima (P _min) as well as the amplitude (ΔP) were determined by a blinded study member. The amplitude was standardized (sΔP) by dividing by P _max, and the anti-CCP-positive and anti-CCP-negative patients as well as the RF-positive and RF-negative were compared to each other. In the ultrasonographic evaluation, we found a highly significant difference in sΔP between CCPp and CCPn patients (median 19.0 vs. 42.9 %, p < 0.0001). sΔP is independent of disease activity. The absolute amplitude ΔP did not differ between the groups. Also, in anti-CCP-positive patients there was a completely linear correlation between P _max and P _min, and this was far less marked in anti-CCP-negative patients. Anti-CCP-positive and anti-CCP-negative RA display different PDS oscillation patterns. This constitutes a nonserological parameter to differentiate between the two forms. The difference in PDS oscillation patterns suggests that the underlying pathological process differs between the forms.

[Operative therapy for rheumatoid arthritis of the hand]

The need for operative treatment of severe rheumatic deformities of the hand and wrist is decreasing due to the increased use of disease-modifying drugs; however, some patients do not tolerate or do not sufficiently respond to these drugs, which often results in the hands being affected and in advanced stages to severe deformity and loss of function. In these cases operative surgery can help to slow the progression of rheumatic destruction and restore the function of the patient's hand. This article describes the principles of surgery for rheumatoid arthritis of the hand. A meticulous synovectomy or tenosynovectomy is the first stage of treatment. With progression of rheumatic destruction various salvage procedures are necessary to preserve the best possible functional state.

[Operative treatment of the rheumatic shoulder]

The duration and severity of rheumatic diseases of the shoulder correlate with symptom frequency, structural changes and associated functional limitations. The multifactorial character of the underlying rheumatic disease requires a multimodal therapeutic concept including interaction of surgical and non-surgical disciplines. In addition to basic systemic anti-inflammatory medication, injections targeting the synovial tissue by corticoid instillation and glenohumeral radiosynoviorthesis (with an intact rotator cuff) are further options. Operative interventions on rheumatic shoulders can be characterized as disease-modifying, protective, reconstructive or palliative, depending on the stage. Combining minimally invasive arthroscopic surgical techniques with modern basic therapy has the potential to shift the indications for operative interventions towards an earlier stage of disease without favoring or propagating structural alterations which have already occurred. In cases of severe joint destruction with loss of the rotator cuff, reverse shoulder arthroplasty can be an appropriate option.

3D imaging options and ultrasound contrast agents for the ultrasound assessment of pediatric rheumatic patients

The application of 3D imaging in pediatric rheumatology helps to make the assessment of inflammatory changes more objective and to estimate accurately their volume and the actual response to treatment in the course of follow-up examinations. Additional interesting opportunities are opened up by the vascularity analysis with the help of power Doppler and color Doppler in 3D imaging. Contrast-enhanced ultrasound examinations enable a more sensitive assessment of the vascularity of inflamed structures of the locomotor system, and a more accurate analysis of treatment's effect on changes in vascularity, and thereby the inflammation process activity, as compared to the classical options of power and color Doppler. The equipment required, time limitations, as well as the high price in the case of contrast-enhanced ultrasound, contribute to the fact that the 3D analysis of inflammatory changes and contrast-enhanced ultrasound examinations are not routinely applied for pediatric patients.

Tracking rheumatic disease through imaging

This review recounts the historical, current, and future involvement of radiology and imaging in the diagnosis, management, and follow-up of patients with various rheumatic conditions. Radiographs are the mainstay of imaging patients with rheumatic conditions, although magnetic resonance imaging and ultrasonography are routinely used for early diagnosis of disease. Computed tomography remains useful in evaluating the extent of involvement of inflammatory spondyloarthropathies that classically involve the axial skeleton and sacroiliac joints. Molecular imaging has begun to play an innovative role in evaluating patients with arthritis, aiming to identify disease earlier and provide greater specificity.

[Radiological imaging in early diagnosis of rheumatoid arthritis. The role of ultrasound and magnetic resonance imaging]

CLINICAL/METHODICAL ISSUE

For optimal therapy management of patients with rheumatoid arthritis (RA) specific and sensitive diagnostic methods are essential for assessment of disease activity.

STANDARD RADIOLOGICAL METHODS

In addition to projection radiography, imaging techniques, in particular magnetic resonance imaging (MRI) and ultrasound (US) are becoming increasingly more important for the early diagnosis of RA.

PRACTICAL RECOMMENDATIONS

The MRI and US techniques play a key role in the early imaging diagnostics of RA. Measurement of inflammation activity represents the basis of therapeutic decision-making and can be quantitatively and qualitatively determined with MRI and US. Synovitis and bone marrow edema are predictors of erosion.

Radiographic estimation in seropositive and seronegative rheumatoid arthritis

Long since it have been suggested that a subpopulation of patients with rheumatoid arthritis, diagnosed with negative rheumatoid factor tests, represents a clinical entity quite distinct from that of seropositive rheumatoid arthritis (RA). Our aim was to establish a scientific comparative analysis between seronegative and seropositive rheumatoid arthritis, regarding some radiological and clinical parameters, applied for the first time on patients from Kosovo. Two hundred fifty patients with rheumatoid arthritis according to the American College of Rheumatology criteria were retrospectively studied by analysis the radiographic damage and clinical parameters of the disease, using a data base. All examinees were between 25-60 years of age (Xb=49.96, SD=10.37) with disease duration between 1-27 years (Xb = 6.41, SD=6.47). All patients underwent a standardised evaluation radiographs. Baseline standardised poster anterior radiographs of hands and feet and radiographs of other joints, depending on indications, were assessed. Erythrocyte sedimentation rate values correlated with the radiological damages and statistical difference was found for seronegative subset (r=0.24, p<0.01). Longer duration of the disease resulted in the increase of radiological changes in both subsets (r=0.66, p<0.01) seronegative, (r=0.49, p<0.01) seropositive. Anatomic changes of IInd and IIIrd level were nearly equally distributed in both subsets, 76 (60.8%) seronegative, 75 (60%) seropositive. Radiological damages are nearly equal in both subsets, elevate in relation to the duration of the disease and correlate with ESR values. Regarding the sero-status, differences within sex, with some exceptions, are not relevant. Although there are some definite quantitative and qualitative differences regarding sero-status, obviously there is a great deal of overlap between the two groups.

Noninvasive quantitative assessment of synovial pannus angiogenesis by contrast-enhanced gray-scale sonography in antigen-induced arthritis in rabbits

RATIONALE AND OBJECTIVES

The aim of this study was to evaluate the value of contrast-enhanced gray-scale sonography in quantitative assessment of synovial pannus angiogenesis in antigen-induced arthritis in rabbits.

MATERIALS AND METHODS

Twenty-four adult New Zealand White rabbits were divided into two groups. Inflammatory arthritis was induced by intra-articular injection of ovalbumin into right knee joints with 4 mg in low-dose group (LD, n = 12) and 8 mg in high-dose group (HD, n = 12). The left side of the knee on each rabbit was used as normal control. Contrast-enhanced gray-scale sonography with time intensity curve (TIC) was performed on the synovia of suprapatellar bursa and posterior capsules 4 weeks after the injection. Immunohistochemical examinations of synovia were applied to assess the microvessel density and the expression of vascular endothelial growth factor. Correlation analysis between sonographic and immunohistochemical findings was performed.

RESULTS

Contrast-enhanced gray-scale sonography of all right knees demonstrated intra-articular hypoechoic lesions with enhanced blood flow and no abnormal findings on all left knees. Parameters of TIC, including ascending curve (A), derived peak intensity (DPI), and area under curve (AUC) on arthritis joints were significantly higher in HD group compared to LD group (P < .05). Positive correlation was found between immunohistochemical findings and parameters of A, DPI, and AUC (P < .05). However, no correlation was found between other parameters (slope of descending rate, time to peak, time to rise, and initial intensity) and immunohistochemical findings.

CONCLUSIONS

Contrast-enhanced gray-scale sonography with TIC measurement could provide reliable method for noninvasive quantitative assessment of synovial pannus angiogenesis of arthritis in clinical settings.

Detection of vascularity in wrist tenosynovitis: power doppler ultrasound compared with contrast-enhanced grey-scale ultrasound

INTRODUCTION

We sought to assess vascularity in wrist tenosynovitis by using power Doppler ultrasound (PDUS) and to compare detection of intra- and peritendinous vascularity with that of contrast-enhanced grey-scale ultrasound (CEUS).

METHODS

Twenty-six tendons of 24 patients (nine men, 15 women; mean age ± SD, 54.4 ± 11.8 years) with a clinical diagnosis of tenosynovitis were examined with B-mode ultrasonography, PDUS, and CEUS by using a second-generation contrast agent, SonoVue (Bracco Diagnostics, Milan, Italy) and a low-mechanical-index ultrasound technique. Thickness of synovitis, extent of vascularized pannus, intensity of peritendinous vascularisation, and detection of intratendinous vessels was incorporated in a 3-score grading system (grade 0 to 2). Interobserver variability was calculated.

RESULTS

With CEUS, a significantly greater extent of vascularity could be detected than by using PDUS (P < 0.001). In terms of peri- and intratendinous vessels, CEUS was significantly more sensitive in the detection of vascularization compared with PDUS (P < 0.001). No significant correlation between synovial thickening and extent of vascularity could be found (P = 0.089 to 0.097). Interobserver reliability was calculated to be excellent when evaluating the grading score (κ = 0.811 to 1.00).

CONCLUSIONS

CEUS is a promising tool to detect tendon vascularity with higher sensitivity than PDUS by improved detection of intra- and peritendinous vascularity.

Developments in musculoskeletal ultrasound and clinical applications

OBJECTIVE

Ultrasound (US) technologies are rapidly advancing, offering several refined transducer technologies as well as soft and hardware facilities. The aim of this article is to outline US developments, from B-mode technologies over Doppler advances to more sophisticated technologies, and their potential clinical impact in the field of musculoskeletal (MSK) imaging.

NEW ADVANCES

When using B-mode ultrasound, compound imaging and beam-steering are of help to decrease anisotropy in tendons and ligaments, that are less well depicted due to their oblique course. Doppler imaging has become sensitive in the detection of flow in small vessels, which is of particular value in rheumatologic conditions, tumour and overuse assessment. The use of US microbubble contrast agents improves detection of low-volume blood flow in smaller vessels by increasing the signal-to-noise ratio and thereby facilitating detection of angiogenetic vessels in inflammatory conditions or tumours. The use of US blood pool contrast agents enables molecular imaging in real-time, and thus the diagnostic potential of US is expanded, opening up a new field of US applications. Objective quantification of altered tissue (e.g., synovial proliferation, tumours) is still demanding and might be improved by the use of three-dimensional imaging and software tools as parametric evaluation. Real-time sonoelastography (EUS) is a new development for visualization of tissue elasticity by measurement of tissue displacement in terms of tissue stiffness changes, promising new insights into tendon disorders. Image fusion is an exciting development that enables superimposition of CT/MRI data sets on real-time US scanning. This technique might be helpful in guiding injections under real-time conditions even in regions less easily accessible by US as, for instance, the axial skeleton, and can additionally provide an interesting tool for teaching MSK imaging and ways to guide interventions.

CONCLUSION

In summary, exciting developments are expanding the applications of US in the MSK field, offering the advantages of real-time performance, high tissue resolution and relative speed at a reasonable cost.

Semi-quantitative analysis of rheumatoid finger joint synovitis using power Doppler ultrasonography: when to perform follow-up study after treatment consisting mainly of antitumor necrosis factor alpha agent

PURPOSE

To determine the timing for follow-up study of power Doppler ultrasonography (PDUS) by evaluating the response of finger joint synovitis in patients with rheumatoid arthritis (RA) to treatment including infliximab, an antitumor necrosis factor alpha agent.

METHODS AND MATERIALS

Bilateral second/third metacarpo-phalangeal (MCP) joints and second proximal inter-phalangeal (PIP) joints (total of six joints) in 21 patients (18 women and three men; median age 53 years) with chronic active RA were assessed by PDUS before and after 2 weeks, 6 weeks, 14 weeks, 30 weeks, 38 weeks, 46 weeks, and 54 weeks of infliximab infusion. Pulse Doppler settings were standardized for each patient and optimized for the detection of synovial blood flow by adjustment of color gain, pulse repetition, and flow optimization. Power Doppler signal was graded for each joint [joint grade for power Doppler (JGPD) signals], and the sum of the grades of six joints was defined as the PDUS index [joint index for power Doppler signals (JIPD)] at each visit. PDUS and clinical parameters [28-joint disease activity score (DAS28), health assessment questionnaire, and C-reactive protein (CRP) level] were independently assessed and compared with baseline values. The American College of Rheumatology (ACR) core set responders and non-responders at week 54 were compared for clinical parameters and PDUS index at each visit.

RESULTS

Fourteen patients completed the planned treatment for 1 year, while six patients dropped out for various reasons and one died suddenly. PDUS was performed a total of 146 times on 467 joints. DAS28 was assessed 127 times. Both DAS28 and JIPD had decreased at the follow-up. Comparative analysis between DAS28 and PDUS was available 125 times. The transverse correlation between the PDUS index and DAS28 was not significant throughout the follow-up period. When responders and non-responders were discriminated at week 54, a logistic regression model for the binary endpoint of responder vs non-responder, with PDUS index as explanatory variable at time point 0, and follow-up revealed statistical significance from week 38 and on.

CONCLUSION

PDUS reflected infliximab's effect on pannus vascular signals; this effect was observed as early as 2 weeks after treatment had begun. Also, the responders to treatment at 54 weeks tended to have fewer JIPD than non-responders in the follow-up period. PDUS may be performed at week 38 or later to foresee the response to the treatment at week 54.

Response of symptoms and synovitis to intra-muscular methylprednisolone in osteoarthritis of the hand: an ultrasonographic study

OBJECTIVE

To examine the relationship between ultrasound (US)-detected synovial pathology in hand OA and the clinical response to parenteral corticosteroids.

METHODS

People with symptomatic OA of the hand completed questionnaires [visual analogue scale (VAS) pain, Australian Canadian Osteoarthritis Hand Index and VAS global] and underwent an US examination of both hands prior to receiving an i.m. dose of methylprednisolone. Four- and twelve-week assessments were performed to assess therapeutic response.

RESULTS

Thirty-six subjects with established OA were enrolled. Twenty-four (67%) subjects met the primary end-point of a 20% reduction in VAS pain, 25 (69.4%) met the Osteoarthritis Research Society International response criteria at 4 weeks. Overall in the group, there was a reduction in levels of pain in the most painful joint, pain in all joints and in global disease activity at 4 weeks (P < 0.001, P < 0.001 and P < 0.001, respectively). Reduction in symptoms was not associated with a statistically significant reduction in US-detected synovial hypertrophy or power Doppler signal.

CONCLUSIONS

In this observational study, parenteral corticosteroids were associated with a statistically significant reduction in symptoms, but no statistically significant reduction in US-detected synovial inflammation. The latter finding may, however, reflect the relatively low levels of synovial inflammation detected ultrasonagraphically in hand joints.

[Early arthritis: action desired - treatment required]

Rheumatoid Arthritis (RA) is the most prevalent inflammatory joint disease in adults and shows a destructive course in most cases. The outcome of the disease - functional decline and invalidity - necessitates an early therapy. Recent studies demonstrate that the initiation of the treatment with a disease modifying antirheumatic drug (DMARD) treatment within the first three months after the onset of symptoms is crucial for sustained improvement of prognosis as well as therapeutic success and outcome. In the early stage of the disease, the criteria for the classification of Rheumatoid Arthritis (RA) are frequently not met. Up to over 50% of the patients show an arthritis, which cannot be classified and therefore is seen as undifferentiated arthritis (UA). Early therapeutic intervention appears to prevent the chronification of the disease; thus an early and appropriate disease modifying therapy is mandatory. Age, gender, involvement of the hands, positive rheumatoid factor, as well as the detection of anti cyclic-citrullinated peptide antibodies (anti-CCP Ab) are predictors of the development of RA. Beside conventional X-rays, there are other imaging methods such as magnetic resonance tomography imaging, Power-Doppler or contrast medium enhanced sonography, which may enable the detection not only of synovitis but also of erosive lesions at very early stages. Those patients suffering from UA carry a high risk for the development of a destructive arthritis as seen in RA, and therefore should be treated with an adequate DMARD. In these cases methotrexate is still the drug of first choice.

Quantification of synovitis in rheumatoid arthritis: do we really need quantitative measurement of contrast-enhanced ultrasound?

OBJECTIVE

The quantification of synovitis is of great significance for adequate therapy management and follow-up in patients with Rheumatoid Arthritis (RA). The purpose of this study was to validate a semi-quantitative Power Doppler (PD) scoring system by comparing the PD scores to the objective measurement of the synovial inflammation using dynamic contrast-enhanced Pulse-Inversion Harmonic Imaging (PIHI).

MATERIALS AND METHODS

In 27 patients with RA, two radiologists performed semi-quantitative scoring of a PD examination, using a four-point scale from 0 to 3, in the metacarpophalangeal joints, proximal interphalangeal joints, and the wrists. The scores were compared to the area under the time-echo intensity curves obtained by contrast-enhanced PIHI examination. The interobserver agreement for PD scoring was evaluated using the Cohen's kappa test.

RESULTS

Preliminary results showed that the area under the curve of dynamic measurements of PIHI tended to correlate with PD scores. The interobserver agreement for PD scoring was good (kappa=0.768).

DISCUSSION

Based on comparisons with dynamic contrast-enhanced PIHI, semi-quantitative PD scoring might meet the criteria for a reliable, reproducible, and practical scoring system. Although further studies that would include a larger study population are required, our preliminary results show that PIHI may not provide a real benefit for quantification of synovitis in day-to-day practice.

Quantification of synovial and erosive changes in rheumatoid arthritis with ultrasound--revisited

Synovitis is a predictive factor of irreversible changes in the joints, tendons, and ligaments in patients with rheumatoid arthritis (RA). Therefore, the early demonstration of reversible, pre-erosive inflammatory features to diagnose RA, the monitoring of disease activity, and the response to therapy are of great importance. Technical developments in ultrasound now allow the quantification of synovitis and erosions, and enable the assessment and follow-up of disease activity. However, both the subjective and objective quantification techniques are associated with different problems. This review article highlights the advantages and disadvantages of sonographic quantification, and revisits the somewhat controversial positions apparent in the current literature. Familiarity with the imaging findings and the scoring systems used to characterize erosive changes are prerequisites for considerably improving the detection and monitoring of synovitis and erosions. The role of ultrasound in the diagnostic approach to RA, particularly in the quantification of synovial and erosive changes, will be explored and the current literature will be reviewed.

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.

Ultrasonography in the assessment of peripheral joint involvement in psoriatic arthritis : a comparison with radiography, MRI and scintigraphy

The objective of our study was to investigate the role of musculoskeletal ultrasound (US) in the assessment of hand and foot small joints in psoriatic arthritis (PsA). Thirteen consecutive patients with PsA of hands or feet underwent B-mode US using a 9- to 13-MHz transducer and simultaneous magnetic resonance imaging (MRI), bone scintigraphy and radiography. US findings were compared with radiography, MRI and scintigraphy in 190, 182 and 109 joints, respectively. To assess the sensitivity and specificity of US, radiography was considered as gold standard for the detection of erosions and osteoproliferations and MRI as gold standard for the detection of joint effusion and synovitis. US, MRI and scintigraphy had a higher sensitivity in the detection of overall joint pathology than radiography in painful and/or swollen joints (71%, 72%, 82% vs 32%) and clinically unaffected joints (17%, 21%, 9% vs 2%). US and radiography detected more erosions and osteoproliferations than MRI, with low agreement between the methods in the detection of erosions. Radiography was superior to US in the visualisation of osteoproliferations. Joint effusions and/or synovitis were more frequently detected by MRI than US. Agreement between both imaging methods was better in carpal joints, carpometacarpal joint I, metacarpophalangeal (MCP)/metatarsophalangeal (MTP) joint I, II and V than in MCP/MTP III, IV, PIP and DIP joints. Compared with MRI, radiography and scintigraphy, the specificity of US ranges between 0.84 and 0.94, depending on the joint pathology. In conclusion, the diagnostic sensitivity of US in the detection of PsA-related synovitis of hands and feet is lower than MRI and depends on the joint region. However, the low cost and the acceptable specificity suggest that US is a useful imaging method in addition to radiography in PsA of hands and feet.

Value of contrast-enhanced ultrasound in rheumatoid arthritis

The purpose of this review is to describe the spectrum of sonographic findings in rheumatic diseases with respect to the diagnostic potential using US contrast media which prove activity or inactivity in synovial tissue where new treatment regimes target. Synovial activity can be found in non-erosive and erosive forms of primary and secondary osteoarthritis, and in inflammatory forms of joint diseases like rheumatoid arthritis and peripheral manifestations of spondyloarthritis including, ankylosing spondylitis, Reiter's syndrome, psoriatic arthritis and enteropathic arthritis. It can also be present in metabolic and endocrine forms of arthritis, in connective tissue arthropathies like systemic lupus erythematosus or scleroderma and in infectious arthritis. Ultrasound should be used as first-line imaging modality in suspected early cases of RA and other forms of arthritis, whereas contrast-enhanced ultrasound (CEUS) can further enable for sensitive assessment of vascularity which correlates with disease activity.

[Computer assisted radiological diagnostics of arthritic joint alterations]

Computer assisted diagnosis (CAD) schemes are currently used in the field of musculoskeletal diseases to quantitatively assess vertebral fractures, joint space narrowing, andr erosion. Most systems work semi-automatically, i.e. they are operator dependent in the selection of anatomical landmarks. Fully automatic programs are currently under development. Some CAD products have already been successfully used in clinical trials.

[Quantitative imaging in rheumatoid arthritis: from scoring to measurement]

The need of clinical sciences to measure therapy effects on chronic illness led to development, evaluation, and publication of several radiological methods to monitor disease progression of rheumatic diseases. This review article explains the basics and background of scoring and measurement. The radiologist thus learns to report more compactly and to communicate the results more specifically.