Doppler sonographic comparative study on usefulness of synovial vascularity between knee and metacarpophalangeal joints for evaluation of articular inflammation in patients with rheumatoid arthritis treated by infliximab

Blood flow effects of percutaneous peripheral nerve stimulation. A blinded, randomized clinical trial

BACKGROUND

The vasculature function is mainly regulated by the autonomic nervous system. Importantly, the sensory-motor nervous system also innervates peripheral vessels and has the capacity to modulate vascular tone. Here we investigated the effects of electrical stimulation of a mixed nerve trunk on blood flow in deep arteries and muscle perfusion. Our hypothesis is that stimulation of a mixed nerve can modify blood flow.

METHODS

Twenty-nine healthy participants were included into a randomized-crossover and blinded clinical trial. Each subject received a placebo and two percutaneous peripheral nerve stimulation (pPNS) protocols on the median nerve: Pain Threshold continuous Low Frequency (PT-cLF) and Sensory Threshold burst High Frequency (ST-bHF). Blood flow was then assessed bilaterally using Power Doppler Ultrasonography at the main arteries of the arm, and blood perfusion at the forearm muscles. Afterwards, blood flow was quantified using a semi-automatized software, freely shared here.

RESULTS

Placebo, consisting in needle insertion, produced an immediate and generalized reduction on peak systolic velocity in all arteries. Although nerve stimulation produced mainly no effects, some significant differences were found: both protocols increased the relative perfusion area of the forearm muscles, the ST-bHF protocol prevented the reduction in peak systolic velocity and TAMEAN of the radial artery produced by the control protocol and PT-cLF produced a TAMEAN reduction of the ulnar artery.

CONCLUSIONS

Therefore, the arterial blood flow in the arm is mainly impervious to the electrical stimulation of the median nerve, composed by autonomic and sensory-motor axons, although it produces mild modifications in the forearm muscles perfusion.

The correlation of ultrasound-detected synovitis in an individual small joint with overall clinical disease activity in patients with rheumatoid arthritis

OBJECTIVES

To explore the correlation between the ultrasound-detected synovitis in each individual joint at metacarpophalangeal (MCP), proximal interphalangeal (PIP), and metatarsophalangeal (MTP) regions and the clinical disease activity in patients with rheumatoid arthritis (RA).

METHODS

Clinical disease activity was assessed by disease activity score (DAS) based on 28-joint count and erythrocyte sedimentation rate (DAS28-ESR), C-reactive protein (DAS28-CRP), Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI). Gray scale (GS) and power Doppler (PD) synovitis was assessed by ultrasound semi-quantitatively. The correlation between clinical disease activity indices and synovitis score in each joint was assessed using Spearman's rank correlation test.

RESULTS

211 RA patients were included in this study. The whole GS scores of all MCP joints showed the highest correlation with each Clinical Disease Activity Index (r = 0.403-0.452, p < 0.01). Likewise, the whole PD scores of all MCP joints also showed the highest correlation with clinical disease activity (r = 0.332-0.396, p < 0.01). At individual joint level, the highest correlation of GS score with DAS28-ESR (r = 0.411, p < 0.01), DAS28-CRP (r = 0.459, p < 0.01), and SDAI (r = 0.444, p < 0.01) was observed in MCP3 joint while with CDAI (r = 0.421, p < 0.01) in MCP2 joint. The highest correlation of PD score with DAS28-ESR (r = 0.353, p < 0.01), DAS28-CRP (r = 0.399, p < 0.01), CDAI (r = 0.368, p < 0.01), and SDAI (r = 0.377, p < 0.01) was observed in MCP5 joint.

CONCLUSIONS

The ultrasound-detected synovitis at MCP joints, especially MCP2, MCP3, and MCP5 joints, was best correlated with clinical disease activity in most RA cases, in contrast to PIP and MTP joints. Key Points • The correlation of ultrasound-detected synovitis in each individual joint with the clinical disease activity in RA patients is diverse among joint regions. MCP joints showed the best, in contrast to PIP and MTP joints.

Assessing rheumatoid arthritis disease activity with ultrasound

In practice, composite indices are used for rheumatoid arthritis (RA) disease activity evaluation. Despite valid and widely used, not rarely composite indices miss accuracy. Ultrasound (US) is more precise than clinical examination in synovitis appraisal. US-based disease activity estimation depends on the detection of synovitis. The most common synovitis abnormalities are proliferation, effusion, and neoangiogenesis. Gray scale ultrasound identifies synovial hypertrophy and effusion with its good soft tissue contrast. Additionally, power Doppler ultrasound depicts neoangiogenesis within synovia, remarking local inflammation. Several studies have combined local US findings to develop a patient level disease activity index. Most of them summed selected joint scores in an overall score of disease activity and evaluated its correlation with clinical composite indexes. To be incorporated into clinical practice, an overall US score must have some fundamental characteristics such as reproducibility, viability, and sensitivity to change over time. In global US score development, finding the joints that truly estimate individual disease activity is highly challenging. This article presents an up-to-date literature review on assessing RA disease activity with US and depicts the challenges in finding the perfect global US score.

Imaging in rheumatoid arthritis

The optimal management of rheumatoid arthritis (RA) requires tools that allow early and accurate disease diagnosis, prediction of poor prognosis and responsive monitoring of therapeutic outcomes. Conventional radiography has been widely used in both clinical and research settings to assess RA joint damage due to its feasibility, but it has limitations in early disease detection and difficulty distinguishing between active treatments in modern trials. Imaging modalities such as magnetic resonance imaging (MRI) and ultrasound (US) have the advantage of detecting both joint inflammation and damage and hence they can provide additional and unique information. This can be especially useful in the context of early and/or undifferentiated joint disease when detection of soft tissue and bone marrow abnormalities is desirable. This review focusses on the recent literature concerning modern imaging, and provides clinicians with an insight into the role of imaging in modern RA diagnosis, prognosis and monitoring.

Value of power Doppler and gray-scale US in the diagnosis of carpal tunnel syndrome: contribution of cross-sectional area just before the tunnel inlet as compared with the cross-sectional area at the tunnel

Objective

To determine the value of gray-scale and power Doppler ultrasonography in the evaluation of carpal tunnel syndrome (CTS).

Materials and Methods

Median nerves at the carpal tunnel were evaluated by using gray-scale and power Doppler ultrasonography and by using accepted and new criteria in 42 patients with CTS (62 wrists) confirmed by electromyogram and 33 control subjects. We evaluated the cross-sectional area of the nerve just proximal to the tunnel inlet (CSAa), and at mid level (CSAb). We then calculated the percentage area increase of CSAb, and area difference (CSAb-CSAa). We measured two dimensions of the nerve at the distal level to calculate the flattening ratio. The power Doppler ultrasonography was used to assess the number of vessels, which proceeded to give a score according to the vessel number, and lastly evaluated the statistical significance by comparing the means of patients with control subjects by the Student t test for independent samples. Sensitivities and specificities were determined for sonographic characteristics mentioned above. We obtained the receiver operating characteristic (ROC) curve to assess the optimal cut-off values for the diagnosis of CTS.

Results

A statistically significant difference was found between patients and the control group for mean CSAb, area difference, percentage area increase, and flattening ratio (p < 0.001, p < 0.001, p < 0.001, p < 0.05, respectively). From the ROC curve we obtained optimal cut-off values of 11 mm² for CSAb, 3.65 for area difference, 50% for the percentage of area increase, and 2.6 for the flattening ratio. The mean number of vessels obtained by power Doppler ultrasonography from the median nerve was 1.2. We could not detect vessels from healthy volunteers. Mean CSAbs related to vascularity intensity scores were as follows: score 0: 12.3 ± 2.8 mm², score 1: 12.3 ± 3.1 mm², score 2: 14.95 ± 3.5 mm², score 3: 19.3 ± 3.8 mm². The mean PI value in vessels of the median nerve was 4.1 ± 1.

Conclusion

Gray-scale and power Doppler ultrasonography are useful in the evaluation of CTS.

Systematic Review of MRI, Ultrasound, and Scintigraphy as Outcome Measures for Structural Pathology in Interventional Therapeutic Studies of Knee Arthritis: Focus on Responsiveness

Objective.

Validated imaging outcome tools to assess response to therapies in a single joint are required. Our aim was to review the published literature to ascertain the responsiveness of novel imaging techniques as outcome measures in interventional therapeutic studies of knee arthritis.

Methods.

An Ovid Medline search was performed for original articles in English that used imaging techniques to assess response at the knee joint to therapy in osteoarthritis, rheumatoid arthritis, and psoriatic arthritis. Changes in response to therapy were assessed with regard to both internal and external responsiveness.

Results.

In the studies that presented appropriate statistical data to allow responsiveness to be assessed, MRI was generally found to be internally responsive to pathologies imaged, and externally responsive, referenced against both other imaging modalities and biochemical biomarkers of arthritis. Ultrasonography was found to demonstrate internal responsiveness with regard to synovial thickness, effusion size, and popliteal cyst size. External responsiveness was demonstrated against several referenced health status measures. Scintigraphy was found to be externally responsive in the majority of studies, with internal responsiveness demonstrated in 1 study.

Conclusion.

While the imaging techniques appear to be responsive from the data we present, further inspection reveals that interpreting the responsiveness of imaging techniques was difficult, largely because of a lack of standardization of image acquisition, definitions of pathology, and scoring systems. Refined pathological definitions and scoring systems are required to enable the development of valid and responsive tools for interventional clinical trials.

Reliability of different Doppler ultrasound quantification methods and devices in the assessment of therapeutic response in arthritis

OBJECTIVE

To evaluate the metric qualities of power Doppler ultrasound (PDUS) for different quantification methods and devices in the assessment of arthritis during anti-inflammatory treatment.

METHODS

Twenty-four patients with active arthritis and first-time treatment with the TNF-alpha inhibitor adalimumab underwent sequential clinical, laboratory and US examination at baseline, weeks 2, 6 and 12. 2D and 3D PDUS was performed by two independent investigators. The images and movies were scored from 0 to 3 and the amount of colour pixels and voxels was calculated. In addition, the resistance index of a synovial artery was measured. Thirteen patients were examined with a second US machine.

RESULTS

Treatment response was already observed at week 2 with a significant reduction of 2D (P < 0.01) and 3D scores (P < 0.001). A moderate correlation to 28-joint disease activity score was found for 3D voxel count (r(s) = 0.35, P < 0.001). Interobserver agreement was kappa or ICC >or= 0.8 for all methods except the resistance index (ICC = 0.60). Intermachine agreement was kappa = 0.57 for 2D PDUS score.

CONCLUSIONS

The study demonstrates good to excellent interobserver and moderate intermachine reliability of different PDUS assessment methods in a longitudinal open-label study.