[Comparison of contrast-enhanced low mechanical index (Low MI) sonography and unenhanced B-mode sonography for the differentiation between synovitis and joint effusion in patients with rheumatoid arthritis]

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.

Intraoperative Contrast-Enhanced Ultrasound Imaging of Femoral Head Perfusion in Developmental Dysplasia of the Hip: A Feasibility Study

OBJECTIVES

Developmental dysplasia of the hip (DDH) is one of the most common developmental deformities of the lower extremity. Although many children are successfully treated with a brace or harness, some require intraoperative closed or open reduction and spica casting. Surgical reduction is largely successful to relocate the hip; however, iatrogenic avascular necrosis is a major source of morbidity. Recent research showed that postoperative gadolinium-enhanced magnetic resonance imaging (MRI) can depict hip perfusion, which may predict a future incidence of avascular necrosis. As contrast-enhanced ultrasound (CEUS) assesses blood flow in real time, it may be an effective intraoperative alternative to evaluate femoral head perfusion. Here we describe our initial experience regarding the feasibility of intraoperative CEUS of the hip for the assessment of femoral head perfusion before and after DDH reduction.

METHODS

This single-institution retrospective Institutional Review Board-approved study with a waiver of informed consent evaluated intraoperative hip CEUS in children with DDH compared to postoperative contrast-enhanced MRI. Pediatric radiologists, blinded to prior imaging findings and outcomes, reviewed both CEUS and MRI examinations separately and some time from the initial examination both independently and in consensus.

RESULTS

Seventeen patients had 20 intraoperative CEUS examinations. Twelve of 17 (70.6%) had prereduction hip CEUS, postreduction hip CEUS, and postreduction gadolinium-enhanced MRI. Seven of 12 (58.3%) were evaluable retrospectively. All CEUS studies showed blood flow in the femoral epiphysis before and after reduction, and all MRI studies showed femoral head enhancement after reduction. The CEUS and MRI for all 7 patients also showed physeal blood flow.

CONCLUSIONS

Contrast-enhanced ultrasound is a feasible intraoperative tool for assessing adequate blood flow after hip reduction surgery in DDH.

Value of contrast-enhanced ultrasound for detection of synovial vascularity in experimental rheumatoid arthritis: an exploratory study

Objective

This study aimed to examine the associations between contrast-enhanced ultrasound (CEUS) imaging and synovial hypervascularity and synovitis score in a rabbit model of antigen-induced arthritis (AIA), compared with power Doppler ultrasound (PDUS).

Methods

We investigated 50 knee joints in 25 AIA rabbits (AIA group), and 10 knee joints in five sham-injected rabbits (control group). PDUS and CEUS images were evaluated at the 8th week. Ultrasound-guided synovial biopsies were targeted in the area with hypervascularity, and synovial microvessel density (MVD) was evaluated by immunohistochemical staining of CD31.

Results

The PDUS score was significantly higher in the AIA group (2.61 ± 0.78) compared with the control group (0.50 ± 0.53). CEUS in the AIA group revealed a fast-in/slow-out pattern of contrast enhancement. MVD revealed by CD31+ vessel count and the synovitis score were significantly higher in the AIA group compared with the control group. In the AIA group, CEUS findings showed a better correlation with MVD revealed by CD31+ and synovitis score than PDUS findings.

Conclusion

CEUS is superior to PDUS for estimating synovial hypervascularity and hyperplasia in experimental rheumatoid arthritis.

Role of Contrast-enhanced Ultrasound in the Evaluation of Inflammatory Arthritis

Objective:

Contrast-enhanced ultrasound (CEUS) is a well-established imaging modality which has been put into clinical use in recent years with the development of second-generation contrast agent and imaging devices, and its applications in the assessment of inflammatory arthritis, such as rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, have provoked abundant discussion and researches among radiologists and rheumatologists. To summarize the achievements of clinical studies on CEUS in the application of arthritis, and to keep up with the latest progresses of the imaging technique, we reviewed the literature in recent years, hoping to establish the role of CEUS in joint diseases.

Data Sources:

PubMed and EMBASE.

Study Selection:

We searched the database with the conditions “contrast-enhanced ultrasound AND arthritis” with the time limitation of recent 10 years. Clinical studies applying CEUS in inflammatory arthritis and review articles about development of CEUS in joint diseases in English were selected.

Results:

As it is proved by most studies in recent years, by delineating microvasculature within the inflamed joints, CEUS can indicate early arthritis with high sensitivity and specificity. Moreover, the imaging of CEUS has been proved to be consistent with histopathological changes of inflammatory arthritis. Quantitative analysis of CEUS permits further evaluation of disease activity. CEUS also plays a significant role in the therapeutic monitoring of the disease, which has been backed up by a number of studies.

Conclusions:

CEUS may be a new choice for the rheumatologists to evaluate inflammatory arthritis, because of its low price, ability to provide dynamic pictures, and high sensitivity to angiogenesis. It can also be applied in disease classification and therapeutic monitoring. More studies about CEUS need to be done to set up the diagnostic standards.

Clinical utility of eco-color-power Doppler ultrasonography and contrast enhanced magnetic resonance imaging for interpretation and quantification of joint synovitis: a review

With the introduction of new biologics such as anti-TNF-alpha antibodies and other therapies in the treatment of inflammatory arthritis, capable of halting joint destruction and functional disability, there are new pressures on diagnostic and prognostic imaging. Early demonstration of pre-erosive inflammatory features and monitoring of the long-term effects of treatment are becoming increasingly important. Early detection of synovitis offers advantages in terms of allowing early instigation of therapy and may allow the identification of those patients displaying more aggressive disease who might benefit from early intervention with expensive DMARD therapy. Advanced imaging techniques such as ultrasound (US) and magnetic resonance imaging (MRI) have focussed on the demonstration and quantification of synovitis and allow early diagnosis of inflammatory arthropathies such as rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Synovitis represents a potential surrogate measure of disease activity that can be monitored using either MRI or US; the techniques have, generally, focused on monitoring synovial volume or quality as assessed by its vascularity. However to achieve these goals, standardisation and validation of US and MRI are required to ensure accurate diagnosis, reproducibility and reliability. Each modality has different strengths and weaknesses and levels of validation. This article aims to increase the awareness of radiologists and rheumatologists about this field and to encourage them to participate and contribute to the ongoing development of these modalities. Without this collaboration, it is unlikely that these modalities will reach their full potential in the field of rheumatological imaging. This review is in two parts. The first part addresses the role of US and colour or power Doppler sonography (PDUS) in the detection and monitoring of synovitis in inflammatory arthropathies. The second part will look at advanced MR imaging and Dynamic contrast-enhanced MRI techniques and in particular how they are applied to the monitoring of the disease process.

Contrast-enhanced ultrasound in coxitis

OBJECTIVES

Hip involvement is common in rheumatological diseases but can be difficult to diagnose, especially in absence of MRI. B-mode ultrasound (US) detects joint capsule distention while distinguishing effusion from proliferative synovial tissue is strenuous since both appear hypoechoic. Power Doppler ultrasound (PDUS) often fails to detect vascularisation in the hip. We therefore evaluated contrast-enhanced ultrasound (CEUS) in the hip joint.

METHODS

We investigated 36 hip joints of patients with known rheumatological joint diseases presenting with hip pain and 5 hips of healthy controls using B-mode US, PDUS and CEUS. We assessed CEUS hypervascularisation semiquantitatively comparing to the periarticular tissue. In B-mode, we measured the distance between femoral neck and joint capsule (DNC) and compared the results to the avascular intraarticular margin (AIM) in CEUS using t-tests and crosstables.

RESULTS

PDUS signals were received in only 2/36 cases (5.6%). B-mode US established the diagnosis of coxitis in 64% of all symptomatic hip joints. In 4 cases (11%), the diagnosis was revised after the use of CEUS. In patients with definite coxitis, 14 hips (73.7%) showed CEUS hypervascularisation°2, five°1 (26.3%) and none°0 (χ²=3.277, P<0.001). The difference DNC/AIM was highly significant in patients with hip pain (P<0.001, 95% CI: 2.054-4.684) and those with definite coxitis (P<0.001, 95% CI: 3.268-7.258).

CONCLUSIONS

In most cases, clinical parameters together with B-mode US findings are sufficient to diagnose coxitis. However, CEUS is capable of visualizing and quantifying the degree of hypervascularisation and enables the discrimination between effusion and proliferative synovial tissue.

Neue Entwicklungen in der Gelenksonographie

Musculoskeletal ultrasonography has become an established imaging technique in rheumatology. The ability of ultrasonography to visualize soft tissue changes provides a possibility for differentiating between exudative and proliferative synovial tissue changes. Superficial cartilage and bone lesions can be detected earlier by ultrasonography than by conventional radiography. The application of Doppler and power Doppler ultrasonography is helpful for the detection of early inflammation. Current studies with ultrasound contrast media demonstrate its benefit in the differentiation of inflammatory processes. Musculoskeletal ultrasonography is helpful in the diagnosis of early arthritis, especially in patients with inconspicuous conventional radiography or suspicious clinical findings. It is a convenient method for follow-up analysis, and therefore has an impact on the monitoring of therapy. It is patient-friendly and is an important tool for the diagnostic work-up of arthritis.