Diagnostic potential of high resolution ultrasound and nerve conduction study in patients with idiopathic carpal tunnel syndrome

Aim of the work

To evaluate the diagnostic utility of high resolution ultrasound in comparison to nerve conduction study (NCS) in patients with idiopathic carpal tunnel syndrome (CTS).

Interventional applications of intravascular ultrasound imaging: initial experience and future perspectives

Intravascular ultrasound imaging offers the potential to provide more detailed information about vessel and lesion morphology and physiology than is currently available from angiography. The greatest impact of intravascular ultrasound upon clinical decisions may be in the area of cardiac and vascular interventions. To evaluate the utility of intravascular ultrasound, we prospectively studied 45 patients, 11 of whom underwent interventional procedures. Intravascular ultrasound imaging was performed before and after interventions using a 20 MHz, mechanically rotating transducer on either 6.5 Fr or 8.0 Fr catheter systems. Interventions included seven peripheral vessel balloon angioplasties (Femoral artery-two, Renal artery-two, Arteriovenous fistula-two, Aortic coarctation-one), two Femoral artery rotational atherectomies, and two balloon valvuloplasties (Pulmonic valve-1, Mitral valve-1). Intravascular ultrasound and digital angiography provided similar information about vessel size. However, morphological information about the vessel wall, plaque composition, plaque topography, luminal thrombus, and vessel dissections was better appreciated by intravascular ultrasound. Intravascular ultrasound was determined to have provided unique and clinically useful information in 10/11 (91%) interventions. These preliminary data illustrate the potential value of intravascular ultrasound for the evaluation of the vascular system and in particular its value in interventional procedures.     

Percutaneous intracoronary ultrasound imaging: initial applications in patients

This study was designed to evaluate the feasibility and potential clinical utility of intracoronary ultrasound imaging in patients using a 5.5 F synthetic aperture array, over-a-wire ultrasound catheter. Thirty patients underwent percutaneous intracoronary (n = 22) or peripheral (n = 8) ultrasound imaging at the time of cardiac catheterization. Ultrasound images were compared to simultaneous digital angiograms. Correlation between ultrasonic and angiographic estimation of coronary diameters was good (r = 0.80). Morphological analysis of ultrasound images obtained in patients revealed a pattern consistent with mild-to-minimal atherosclerosis, as defined by prior in vitro studies. In 15 patients, imaging was performed during intracoronary infusion of vasoactive medications (papaverine 15 mg, nitroglycerine 100 mugm, and acetylcholine 2 x 10 -5 or 2 x 10 -6M). These medications were also infused during continuous intracoronary Doppler catheter monitoring of velocity and pressure, thus allowing calculation of volume flow and coronary resistance indices. Serial determination of ultrasound-derived epicardial vessel cross-sectional area demonstrated no change (-1 +/- 1%) after papaverine, an 8 +/- 2% increase after nitroglycerine, and a 9 +/- 3% decrease after acetylcholine. Calculated resistance fell 53 +/- 4% after acetylcholine and 60 +/- 3% after papaverine. Preliminary in vitro studies using a combination angioplasty balloon/ultrasound catheter demonstrated the ability to visualize vessel dilation in real time. We conclude that intravascular ultrasound imaging will be useful for dimensional and morphological characterization of vascular disease, for beat-to-beat monitoring of vasomotion, and potentially as a real-time adjunct to therapeutic interventions.     

神经超声在周围神经疾病中的诊断应用

周围神经病是一种原发于周围神经系统结构或功能损害的疾病,其病因及诊断复杂。近几年神经超声的研究对周围神经病的诊断有一定的辅助价值。本文围绕神经超声在诊断周围神经疾病中的作用综述如下。     

Comparative studies of angioscopy and ultrasound for the evaluation of arterial disease

In this in vitro investigation, we studied the histopathological basis for intravascular ultrasound image interpretation and how this technique compares with fiberoptic angioscopy in assessing atherosclerosis. This article presents the sensitivity and specificity of these techniques in the recognition of arterial abnormalities. The relevance of these data in interventional therapeutic procedures and the clinical implications of intravascular imaging methods are also discussed.     

Intravascular and intracardiac ultrasound imaging: current research and future directions

Intravascular and intracardiac ultrasound imaging is a newly emerging catheter-based imaging modality with considerable promise. This review article presents the rationale behind attempts at developing intravascular imaging methods, the design features of intravascular instrumentation, the knowledge obtained with in vitro studies, the in vivo experience in humans, and the potential applications of intravascular imaging in arterial atherosclerosis. The feasibility of pulmonary artery imaging and the potential applications of intracardiac echocardiography are discussed. Finally, future directions in intravascular imaging are outlined.     

Carotid Intima‐Media Thickness Assessment in Refinement of the Framingham Risk Score: Can It Predict ST‐Elevation Myocardial Infarction? A Pilot Study

Patients who suffer a first ST‐elevation myocardial infarction (STEMI) typically have fewer identifiable risk factors than those who suffer other types of acute coronary syndromes. As such, risk assessment tools such as the Framingham Risk Score (FRS) often fail to classify these patients as high risk. In this study, we tested the ability of assessment of carotid intima‐media thickness (CIMT) to enhance the ability to identify patients who are at risk for STEMI, using a CIMT‐derived “vascular age” in place of chronologic age in the calculation of FRS. We applied a CIMT‐based vascular age to the assessment of FRS in a cohort of patients who presented with a first STEMI. Using CIMT‐derived vascular age in place of chronologic age increased both the mean FRS and predicted 10 year cardiovascular event rate of the cohort. More importantly, the use of a CIMT‐derived vascular age in the calculation of FRS significantly improved the ability to identify patients with STEMI as high risk and candidates for statin therapy based on ATPIII criteria (19.2% vs. 57.7%, P = 0.010). The use of CIMT to derive a vascular age may improve the ability of FRS to identify patients at risk for STEMI.     

Effects of Temperature on Albunex and FS069 Echocardiographic Contrast Agents: In Vitro Investigation Using Ultrasonic Irradiation

The effects of temperature on the stability of two contrast agents, Albunex and perfluoropropane filled albumin microspheres (FS069), were investigated by studying the variations in their reflective properties, induced by high dose ultrasound irradiation at different temperatures. Diluted contrast agents were introduced into a 3.5-mL latex balloon, placed in a plastic water tank, and continuously irradiated over a period of 6 minutes using different power levels: 0, 20, 25, and 30 dB. The irradiation was interrupted for imaging every 30 seconds for 2 seconds. The protocol was carried out at three different temperatures: 8°C, 22°C, and 37°C. For each temperature, the concentration of contrast solution was matched to produce approximately the same initial video intensity. Time variations in mean video intensity in the balloon cross section were studied. Contrast enhancement was found to be directly related to temperature. Under continuous ultrasonic irradiation, video intensity gradually decreased over time. This decrease was dependent on both transmitted power and temperature, and was more pronounced with Albunex when compared to FS069 (P < 0.05). Abruptly dropping temperature consistently resulted in rapid, irreversible disappearance of contrast induced by Albunex. Temperature affects the reflectivity and stability of diluted Albunex and FS069. To enhance the reproducibility of contrast enhancement achieved by these agents, their temperature should be carefully controlled.     

Two aortic valves in the parasternal long‐axis view: Aortic dissection or artifact?

Refraction artifact produced the appearance of two aortic valves in the parasternal long axis view. Aortic dissection was ruled out by CT angiography.     

Reproducibility of quantitative measurements from intracoronary ultrasound images: Beat-to-beat variability and influence of the cardiac cycle

OBLECTIVES: The purpose of this study was to determine the variability ofquantitative measurements from intracoronary ultrasound images,and the influence of the cardiac cycle on this variability,as a basis for in vivo applications. METHODS: Methods Two observers analysed 30 MHz cross-sectional imagesfrom 96 in-vivo coronary arterial sites. By computer-assistedcontour tracing we determined lumen area, vessel area, lesionarea (vessel area minus lumen area) and percent obstruction(l00% x lesion area/vessel area). Intra- and inter-observerand beat-to-beat variability, and systolic to diastolic differenceswere calculated by paired analysis. RESULTS: Consistent intra- and inter-observer differences (bias) weresmall (0·9%). Random variations in the two direct parameterswere 21·l%, but for the two derived parameters they wereup to 40%. For all four parameters, random inter-observer variabilitywas significantly greater (up to 119% for vessel area: 19·3vs 8·8%) than intraobserver variability, but consistentvariability was similar. Consistent beat-to-beat differenceswere small (1·4%), random variations were 8·9%to l7·5%. Random beat-to-beat variability for all fourparameters was greater in diastolic than in systolic frames(up to 47·0% difference (11·9 vs 17·5%)for lesion area). Vascular dimensions were significantly greaterin systole (2%). We found an error of 0·24 mm (2SD) forintra-observer variability of calculated mean arterial diameters,which is similar to the error described in angiographic studies(0·22 mm). CONCLUSIONS: Quantitative measurements from intracoronary ultrasound imagesgenerally reproduce well. It is preferable to use directly measuredparameters as opposed to derived parameters, as they are lesssubject to variability. Variability can be reduced by selectingsystolic images. (Eur Heart J 1996; 17: 1593–1599)     

Intravascular ultrasound cross-sectional arterial imaging

In this paper we review the current status of intravascular ultrasound. Data from qualitative and quantitative studies is presented. Our experimental findings and those of other investigators are reviewed. Intravascular ultrasound has been shown to delineate normal and abnormal arterial morphology as well as to identify and differentiate fibrous, lipid-rich, calcified plaques and complicated plaques. Quantitative studies show strong correlations between ultrasound and histology for lumen area, wall thickness, and plaque area. In vivo studies from our experimental work and clinical laboratory as well as the work of other researchers is presented. This data supports the potential of ultrasound imaging for guidance of intravascular intervention. The potential advantages and limitations of this new technology are discussed. This methodology shows promise for the assessment of the extent and severity of atherosclerosis, monitoring its progression and regression and guiding intravascular plaque ablation technologies.     

Examination of Intercostal Arteries with Transthoracic Doppler Sonography

Objective: There has been no study on the measurement of blood flow of the intercostal artery (ICA) or lumbar artery (LA) with the use of transthoracic Doppler sonography. Here, the method of the ICA depiction and flow measurement were described, and we suggested the clinical usage of this method. Methods: Twelve healthy subjects were examined. The performance of transthoracic Doppler sonography was approached from the back on lateral decubitus position. The intercostal artery was depicted by two-dimension mode with color flow, and the inner diameter was measured. Peak systolic velocity (PSV), end-diastolic velocity (EDV), velocity-time integral (VTI), and heart rate (HR) were measured with pulsed Doppler, and the blood flow was calculated. Results: Bilateral ICAs and LAs from Th4 to L4 were measurable with this method. The PSV of Lt Th9 was the fastest at 43.3 ± 10.1 cm/sec and the PSV of the ICAs gradually decreased as distance from Th9 increased. As for the flow volume, the left Th11 was the greatest at 99.7 mL/min, and the flow volume of the ICA gradually decreased as distance from Th11 increased. The velocity and blood flow of right ICA tended to be lower than the left in the same spinal level. Conclusions: Evaluation technique of serial ICAs and LAs was shown. We think that it may be a clinically useful method in the study of spinal cord circulation in the repair of cases of descending thoracic or thoracoabdominal aortic aneurysm. (Echocardiography 2010;27:17-20)     

Comparison of ultrasound and magnetic resonance imaging for diagnosis and follow‐up of joint lesions in patients with haemophilia

Haematomas and recurrent haemarthroses are a common problem in haemophilia patients from early age. Early diagnosis is critical in preventing haemophilic arthritis, and recent years have seen excellent advances in musculoskeletal ultrasound as a diagnostic tool in soft tissue lesions. In this study, we compared the results of ultrasound imaging for the diagnosis of musculoskeletal injuries in haemophilia patients with scores obtained using magnetic resonance (MRI) scans. A total of 61 haemophilia patients aged 4–82 years were included in this study. Both knees and ankles of each patient were assessed using the Gilbert (clinical assessment) and Pettersson scores (X‐ray assessment). Patients with severe haemophilia (n = 30) were examined using ultrasound and MRI (Denver scoring system). Results obtained with ultrasound and MRI in severe patients were correlated using the Pearson test. In patients with severe haemophilia, normal joints were similarly assessed with MRI and ultrasound (κ = 1.000). By component of joint assessment, haemarthrosis was similarly diagnosed with both techniques in all joints (κ = 1.000). A good positive correlation was found between these techniques in detecting and locating synovial hyperplasia (κ = 0.839–1.000, knees and ankles respectively), and erosion of margins (κ = 0.850–1.000). The presence of bone cysts or cartilage loss was better detected with MRI (κ = 0.643–0.552 for knees and ankles, and κ = 0.643–0.462 respectively). Ultrasound is useful in detecting joint bleeds, synovial hyperplasia and joint erosions, with results comparable to those of MRI. A quick and affordable technique, ultrasound imaging may be useful for monitoring joint bleeds and structure normalization and maintenance in routine practice.     

Assessment of synovitis in early rheumatoid arthritis by CXCL13 serum levels and power Doppler ultrasonography: Correlation with disease activity

Aim of the workAssessment of synovitis in rheumatoid arthritis (RA) is a major issue for proper treatment; it has been proven that high resolution ultrasound (US) examination could be of valuable help. The B-cell chemokine, CXCL13, is a proposed serum biomarker of synovitis in RA. We aimed to find out the presence of synovitis in patients with recent-onset RA and its correlation with disease activity.Patients and methodsWe evaluated 30 patients with early RA for the presence and degree of synovitis by performing high resolution US and obtaining serum CXCL13 levels. In addition, we correlated these results with disease activity score 28 (DAS 28). Results of high resolution US and serum CXCL13 were also obtained for 20 healthy age- and sex-matched volunteers and served as controls.ResultsSerum CXCL13 level was significantly increased in early RA patients vs. controls (p < 0.001). High resolution US revealed that RA patients had a significant increased synovial thickness and high power Doppler US score. In RA patients, DAS 28 had a significant correlation with serum CXCL13 (r = 0.42, p = 0.02), synovial thickness (r = 0.39, p = 0.03) and power Doppler US score (r = 0.43, p = 0.02). Serum CXCL13 level correlated with synovial thickness (r = 0.63, p = 0.001) and power Doppler US score (r = 0.69, p = 0.001).ConclusionRecent-onset RA patients suffer from synovitis as evidenced by significantly increased serum CXCL13 and by high resolution US. Serum CXCL13 is a reliable marker of synovial inflammation which correlates better with synovial thickening and power Doppler US scores than DAS28.     

Product review: The Coreco Oculus-500 imaging system

Recent developments in computer imaging technology have brought about significant improvements in the display resolution and capabilities of desk-top imaging systems. The Coreco, Inc. Oculus-500 is a group of high resolution imaging boards for use with IBM-AT and compatible computers. The tested $8000 system consists of a 2 Mb interface board, display/controller board, driver, toolkit, and software interface package. With a display resolution of 1280 × 1024 @ 60 Hz non-interlaced, the OC-500 offers excellent resolution. The accompanying software is being further developed by a responsive company, but can in places be tedious to use. However, the result of understanding the software is a system with superb capabilities.     

Intravascular ultrasonic assessment of lumen geometry and distensibility of the angiographically normal artery: a correlation with quantitative angiography

The feasibility of assessing lumen diameter and area using a 30-MHz mechanically driven ultrasound imaging device was evaluated in vitro in phantoms and in vivo in eight human arteries (six iliac, two brachial). Ultrasound data were compared to angiographic data derived from the cardiovascular angiographic analysis system. In addition, the change of lumen area in a given cardiac cycle was determined in each patient. A close relation between ultrasound and angiography was observed in the phantom studies. In the first three patients there was disagreement; ultrasound images showed larger values compared to the angiographically derived values. Disagreement was related to the use of nominal measurements of the sheath supplied by the manufacturer as calibration. Data on the five other patients showed a close relation between the values derived with ultrasound and angiography. The arterial lumen area revealed a 5% +/- 2% change during one cardiac cycle. The intra- and interobserver variability test showed good correlation for the ultrasound study. This study demonstrates that intravascular ultrasound is an accurate and reproducible technique to measure vascular diameter, lumen area, and arterial wall distensibility in vivo.     

Intravascular ultrasound virtual histology imaging in acute ST-elevation myocardial infarction: A useful clinical tool during primary percutaneous coronary intervention

We described the novel use of intravascular ultrasound-virtual histology (IVUS-VH) imaging in two young adult male patients who presented with acute inferior ST-elevation myocardial infarction (STEMI) and we highlight the usefulness of this new invasive coronary imaging technique. Both patients had thrombotic occlusion of the right coronary arteries but the underlying pathophysiological mechanisms leading to acute thrombosis were different. The in vivo information obtained by IVUS-VH imaging was invaluable in pinpointing the likely etiology of STEMI and thus, guided our primary percutaneous coronary intervention strategy appropriately.