The value of contrast-enhanced color Doppler ultrasound in the detection of vascularization of finger joints in patients with rheumatoid arthritis

New developments in imaging for diagnosis and therapy monitoring in rheumatic diseases

The availability of therapeutic modalities that are able to stop inflammatory joint damage has also markedly influenced recent developments in muskuloskeletal imaging. One focus of interest is the detection of joint pathology as early as possible in order to prevent erosive bony changes. Ultrasonography and magnetic resonance imaging are the most valuable technologies in this respect. Another focus is on the exact assessment and documentation of joint damage using scoring systems not only in therapeutic trials, but also in clinical practice. In addition to these recent advances in peripheral and axial joint imaging, this chapter also discusses advances in vascular imaging and scintigraphy in rheumatoid diseases as well as interventional procedures guided by imaging technologies.

Imaging in early arthritis

Imaging can play a vital role in the evaluation of patients with early arthritis. Various imaging methods can be utilized to aid with diagnosis, predict prognosis and follow disease progression and treatment response. Previously, conventional radiography was the principal method used to evaluate and follow bone damage in patients with inflammatory arthritis. More recently the use of magnetic resonance imaging and ultrasonography has gained wider acceptance and popularity due to the ability of these multiplanar techniques to image both bone changes and soft tissue abnormalities, including synovitis. This chapter discusses the current imaging modalities used in the evaluation of patients with early arthritis, as well as the use of imaging in establishing the extent of disease, in prognosis and in monitoring disease course. Current data on imaging of patients with early arthritis due to rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis is reviewed.

Doppler sonography in rheumatology

The importance of ultrasonography in rheumatology has increased dramatically within the last few years both with regard to clinical practice and to research. High-resolution colour Doppler ultrasound equipment is, to date, widely available. Colour and power Doppler studies of intra-articular and peritendinous blood flow allow an estimation of the inflammatory activity and aid in distinguishing anatomical structures. Contrast agent increases the ability of ultrasonography to detect even minor perfusion. These findings have a practical clinical impact on the management of inflammatory rheumatic diseases. The resolution of ultrasonography is superior to that of magnetic resonance imaging (MRI) and computed tomography (CT) with regard to superficial anatomical structures. Furthermore, ultrasonography can depict the artery wall in contrast to angiography. In temporal arteritis and Takayasu's arteritis, ultrasonography depicts characteristic, homogenous wall thickening, stenoses and acute occlusions. These pathologies resolve quickly with treatment in the temporal arteries and much more slowly in larger arteries.

Serum vascular markers and vascular imaging in assessment of rheumatoid arthritis disease activity and response to therapy

Vascular pathology, in the form of angiogenesis, is important in the perpetuation of rheumatoid arthritis (RA) and, in the form of endothelial dysfunction, contributes to associated cardiovascular co-morbidity. Emerging evidence suggests that TNFalpha blockade may modify vascular pathology in RA. Serum concentrations of vascular endothelial growth factor (VEGF), a potent endothelial cell-specific growth factor that is up-regulated by pro-inflammatory cytokines and by hypoxia, are elevated in RA and correlate with disease activity. Serum levels of VEGF at first presentation in RA predict radiographic progression of the disease over the subsequent year. Power Doppler ultrasonography is a sensitive method for demonstrating the presence of blood flow in small vessels and the vascular signal correlates with histopathological quantification of the vascular density of synovial tissue. Recent data indicate that high-frequency ultrasound and power Doppler are sensitive tools for evaluation of disease activity and assessment of response to therapy. Power Doppler imaging may also have the potential to predict those patients most at risk of accelerated joint destruction. However, much work has yet to be done to standardize the use of these imaging technologies.

Remitting seronegative symmetrical synovitis with pitting edema of the hands: Ultrasound, color doppler ultrasound, and magnetic resonance imaging findings

OBJECTIVE

To assess the value of gray-scale ultrasound (US), color Doppler ultrasound (CDUS), contrast-enhanced CDUS, and magnetic resonance imaging (MRI) in the diagnostic evaluation of the hands in patients with remitting seronegative symmetrical synovitis with pitting edema (RS3PE).

METHODS

Eight patients (5 men, 3 women; mean +/- SD age 69.3 +/- 7.2 years) with clinical diagnosis of RS3PE syndrome underwent US, CDUS, contrast-enhanced CDUS, and MRI. US was performed with a linear array transducer operating at 12 MHz. The US contrast agent (SHU 508; Levovist, Schering, Germany) was intravenously infused in a concentration of 300 mg/ml at a rate of 1 ml/minute.

RESULTS

All patients showed symmetric subcutaneous edema and synovitis of tendons and finger joints on both US and MRI. Vascularity was detected subcutaneously in tendon sheaths and in the joint synovia on CDUS and MRI. Detection of increased vascularity was improved after contrast administration compared with unenhanced CDUS (P < 0.01).

CONCLUSION

Ultrasound, CDUS, contrast-enhanced CDUS, and MRI are valuable tools in the diagnostic evaluation of involved anatomic structures in patients with RS3PE. Contrast-enhanced CDUS is superior to CDUS in assessment of inflammatory edema, effusion, and synovitis.

Rheumatoid and psoriatic knee synovitis: clinical, grey scale, and power Doppler ultrasound assessment of the response to etanercept

OBJECTIVE

To determine the effect of tumour necrosis factor alpha (TNFalpha) blockade with etanercept in refractory knee joint synovitis (KJS) in rheumatoid and psoriatic arthritis, by local and systemic disease activity assessment and combined grey scale and power Doppler ultrasonographic monitoring.

METHODS

27 knees affected by rheumatoid KJS (n = 12) and psoriatic KJS (n = 8) were assessed before receiving treatment and at 3 and 12 months' follow up. Time dependent clinical changes in disease activity were monitored by C reactive protein, erythrocyte sedimentation rate (ESR), global health status (GHS), and Ritchie (RAI) and knee joint articular (KJAI) indices; synovial changes were monitored by ultrasonographic and power Doppler indices for grey scale synovial thickening and for distinct intrasynovial vessel power Doppler flow configurations (fluid/synovium interface (F/SI-PD) and pannus/cartilage interface (P/CI-PD)). Interobserver and intraobserver variability of grey scale and power Doppler ultrasonographic was evaluated. Response to treatment was assessed by analysis of variance for repeated measures on clinical and ultrasonographic variables.

RESULTS

Rapid (3 months) reduction in F/SI-PD flow (p<0.001), parallel to reductions of C reactive protein (p<0.05), ESR (p<0.001), KJAI (p<0.002), RAI, and GHS (p<0.001), was sustained at 12 months when it was accompanied by reduction in both synovial thickening and P/CI-PD flow (p<0.001). No differences (ANOVA) were noted at baseline or at 12 months in clinical and ultrasonographic variables between either the rheumatoid or the psoriatic KJS groups.

CONCLUSION

Grey scale and power Doppler ultrasonography are reliable measures of long term change in rheumatoid and psoriatic KJS disease activity in response to anti-TNFalpha treatment with etanercept.

Doppler ultrasound findings in healthy wrists and finger joints

OBJECTIVE

To evaluate the presence of flow by Doppler ultrasound (DUS) in the wrist and finger joints (carpometacarpal 1 (CMC1), metacarpophalangeal (MCP), and proximal interphalangeal (PIP) joints) of healthy controls.

METHODS

Twenty seven healthy volunteers (15 women, 12 men; mean age 45 years, range 18-93) with a total of 324 joints were examined by DUS. The synovial vascularisation was determined by colour Doppler and the spectral Doppler resistive index (RI). Patients were only included if no synovitis was suspected at the clinical examination and the values for biochemical analysis were within the normal range.

RESULTS

We found colour pixels in 15 of the 27 examined wrist scans and in 8 of these a measurable RI. In the CMC1 joint, colour pixels were found in 11 of the 27 scans and in 9 of these a measurable RI. For the MCP joints, colour pixels were found in 10 out of 135 scans and in 3 of these a measurable RI. The mean RI for all three types of joints was 0.85 and the mean pixel fraction varied from 0.05 to 0.08. Only one PIP joint scan was found to have colour pixels and a flow with an RI of 0.67.

CONCLUSION

Synovial vascularisation may be detected in healthy subjects using DUS. Newer US machines have higher Doppler sensitivity, and it is necessary to be able to distinguish normal from pathological synovial flow.

Ultrasonography in rheumatoid arthritis: a very promising method still needing more validation

PURPOSE OF REVIEW

Through recent technological advances, ultrasonography allows high-resolution visualization of inflammatory and destructive changes in the small superficial joints of hands and feet, and ultrasonography is increasingly used by rheumatologists for assessment of rheumatoid arthritis patients. It is, therefore, highly relevant to consider the validity of ultrasonographic measures of rheumatoid joint inflammation and damage.

RECENT FINDINGS

Organized by type of validity, data on ultrasonography in rheumatoid arthritis are reviewed. Encouraging reports of high agreement of ultrasonographic findings between observers, with MRI and, in knee and hip joints, histopathologic assessments were recently published. New quantitative and semiquantitative evaluation methods have been suggested, and the first systematic follow-up studies suggest an ability of ultrasonography to monitor joint inflammation and damage. However, a number of essential issues are still largely unexplored, including interscanner variability, sensitivity to change, prognostic value, and value in the diagnosis of rheumatoid arthritis. Suggested areas of priority in research and development of ultrasonography in rheumatoid arthritis are outlined.

SUMMARY

Ultrasonography is a very promising method in the assessment of rheumatoid arthritis joints, but still needs more validation before it can take up its expected role on a scientific basis as an important tool for diagnosis, monitoring, and prognostication of patients with rheumatoid arthritis and suspected rheumatoid arthritis.

Proposal for a sonographic classification of target joints in rheumatoid arthritis

OBJECTIVE

The purpose of this study was to classify sonographically the joint damage of target joints in patients with rheumatoid arthritis (RA).

METHODS

During a 3-year cross-sectional study, standardized arthrosonography of symptomatic target joints was performed in patients with RA. According to those findings, a classification with progressive deterioration of joint alteration in RA was created that grades visible morphological changes of the joint components. Using elbow joints as a subgroup, inter- and intraobserver reliability was calculated.

RESULTS

Examined and included in this study were 1211 joints of 425 patients with RA. The mean disease activity score was 5.2 (range 0.75-7.79). Sonographically visible changes could be classified and divided into six stages. A standardized sonographic evaluation system was developed. In reference to the elbow joint, overall percentages for intra- and interobserver reliability of sonography were 90.8% and 88.8%, respectively.

CONCLUSION

Sonography is a valuable tool for assessing and classifying joint alteration in RA. Particularly in early stages of joint affection, ultrasound is superior to X-ray in detecting soft tissue changes and minor erosions.

Imaging in rheumatoid arthritis--why MRI and ultrasonography can no longer be ignored

Implementing the modern treatment strategy in rheumatoid arthritis (RA), i.e. early initiation and optimal adjustments of aggressive therapies, requires methods for early diagnosis and sensitive monitoring of the disease process. In rheumatoid arthritis clinical trials and routine management, conventional radiography is the pivotal method for diagnosing and monitoring structural joint damage. However, it is insensitive to bone damage at its earliest stages and totally incapable of capturing the primary feature of rheumatoid disease, the synovitis. In comparison with radiography, magnetic resonance imaging (MRI) offers assessment of bone damage with improved sensitivities to early pathology and to change. In addition, detailed assessment of soft tissue changes, including synovitis and tenosynovitis, is possible and MRI findings are of prognostic value for the long-term radiological outcome. Ultrasonography (US) is less validated than MRI, but available data suggests that US offers comparable information on both inflammatory and destructive changes in RA finger and toe joints. Issues of reliability, standardization and documentation limit its value in clinical trials, This article reviews current knowledge on conventional radiography, computed tomography, MRI and US for assessment of peripheral joints in RA. The rationale is provided for MRI being the new gold standard for assessment of RA joints and US becoming a routine bedside tool for improved joint assessments and injections by rheumatologists. Pursuing the goal of improving patient care and disease outcome, rheumatologists can no longer afford to ignore MRI and US as means to measure disease activity and joint damage in rheumatoid arthritis.

New developments in imaging in rheumatoid arthritis

Despite the advances made in medical imaging over the past 3 decades and the central role that magnetic resonance imaging and other sophisticated technologies now play in routine clinical practice, patients with rheumatoid arthritis have benefited relatively little from these advances thus far. Over the past few years, however, evidence has accumulated to show that magnetic resonance imaging and ultrasonography can identify joint damage in patients with rheumatoid arthritis earlier and more sensitively than other techniques can, and that these techniques can directly visualize and monitor changes in synovium and bone that precede actual bone erosion. Much of this development is being driven by the pharmaceutical and biotechnology industries as they search for novel therapies to combat this disease. Accordingly, the imaging tools that ultimately will be used to direct patients to specific therapies and then to monitor treatment effectiveness and safety are currently being refined and validated in rigorous multicenter and multinational clinical trials aimed at gaining regulatory approval of these new therapies. As these therapies become available for clinical use, we can anticipate increased demand for expertise and experience in evaluating disease progression and treatment response, and to the emergence of magnetic resonance imaging systems specifically adapted for this application. The following discussion reviews the current status of this development, and notable advances that have been reported in the literature in the past year.

Disease-modifying antirheumatic drug therapy for spondyloarthropathies: advances in treatment

The inflammatory arthritides included in the category of spondyloarthropathy (ankylosing spondylitis, psoriatic arthritis, reactive arthritis, undifferentiated spondyloarthropathy, and arthritis associated with inflammatory bowel disease) may cause significant, progressive morbidity. Therapy with nonsteroidal antiinflammatory drugs and traditionally used disease-modifying antirheumatic drugs, such as methotrexate, often fails in patients with more severe peripheral arthropathy and axial involvement, and alternative treatment options have been limited. With increased understanding of the pathologic processes involved in these disorders, new therapeutics have arisen and are being investigated in the various subtypes of spondyloarthropathy. This article reviews recent progress in disease-modifying therapy for spondyloarthropathy, including new biologic response modifiers, such as the tumor necrosis factor-alpha inhibitors etanercept and infliximab.

Diagnostic value of high-resolution B-mode and doppler sonography for imaging of hand and finger joints in rheumatoid arthritis

OBJECTIVE

High-resolution sonography enables a detailed assessment of intraarticular and extraarticular soft tissue abnormalities of joints affected by rheumatoid arthritis (RA). This study was undertaken to evaluate the diagnostic value of B-mode sonography and power Doppler compared with that of clinical examinations and conventional radiography.

METHODS

The study group comprised 47 patients (14 men, 33 women) with different grades of RA; 31 patients were rheumatoid factor (RF) positive, and 16 were RF negative. The wrists, first through fifth metacarpophalangeal joints, and second through fifth proximal interphalangeal joints of these patients were scored with ultrasound in B-mode and power Doppler application, using a standardized technique. Involvement and severity of inflammation, as well as vascularization, were scored according to a new 3-point scale. The results were correlated with benchmarks of the clinical and radiologic investigations. Clinical status and conventional radiologic status were determined according to the Disease Activity Score and the Larsen score.

RESULTS

After preliminary studies in 15 patients, 39% of 704 joints were found to be abnormal by clinical investigation. Erosions were detected by radiography and sonography in 23% and 43% of joints, respectively. Hypervascularization was observed in 34% of 704 joints by power Doppler application. There was a significant correlation (P < 0.001) between the different methods for the detection of the severity of lesions. Use of a modern, state-of-the-art power Doppler program was necessary for semiquantification, and a standardized investigation technique and scoring system provided sufficient quality measures.

CONCLUSION

Sonography detects 20% more abnormalities than does radiography, and sonography has the potential to provide simple grading of disease activity. The rate of detection of abnormalities was slightly higher with clinical examination compared with sonography.

The value of sensitive imaging modalities in rheumatoid arthritis

X-ray evaluation of rheumatoid joints is relatively inexpensive, is widely available and has standardised methods for interpretation. It also has limitations, including the inability to reliably determine structural change in less than 6-12 months, the need for experienced readers to interpret images and the limited acceptance of this technique in routine clinical practice. High-frequency ultrasound, with or without power Doppler, and magnetic resonance imaging of rheumatoid joints permit an increasingly refined analysis of anatomic detail. However, further research using these sensitive imaging technologies is required to delineate pathophysiological correlates of imaging abnormalities and to standardise methods for assessment.