The emergence of ultrafast frame rates in ultrasonic imaging has been recently made possible by the development of new imaging modalities such as transient elastography. Data acquisition rates reaching more than thousands of images per second enable the real-time visualization of shear mechanical waves propagating in biological tissues, which convey information about local viscoelastic properties of tissues. The first proposed approach for reaching such ultrafast frame rates consists of transmitting plane waves into the medium. However, because the beamforming process is then restricted to the receive mode, the echographic images obtained in the ultrafast mode suffer from a low quality in terms of resolution and contrast and affect the robustness of the transient elastography mode. It is here proposed to improve the beamforming process by using a coherent recombination of compounded plane-wave transmissions to recover high-quality echographic images without degrading the high frame rate capabilities. A theoretical model is derived for the comparison between the proposed method and the conventional B-mode imaging in terms of contrast, signal-to-noise ratio, and resolution. Our model predicts that a significantly smaller number of insonifications, 10 times lower, is sufficient to reach an image quality comparable to conventional B-mode. Theoretical predictions are confirmed by in vitro experiments performed in tissue-mimicking phantoms. Such results raise the appeal of coherent compounds for use with standard imaging modes such as B-mode or color flow. Moreover, in the context of transient elastography, ultrafast frame rates can be preserved while increasing the image quality compared with flat insonifications. Improvements on the transient elastography mode are presented and discussed.

Coherent plane-wave compounding for very high frame rate ultrasonography and transient elastography

Atherosclerosis causes clinical disease through luminal narrowing or by precipitating thrombi that obstruct blood flow to the heart (coronary heart disease), brain (ischemic stroke), or lower extremities (peripheral vascular disease). The most common of these manifestations is coronary heart disease, including stable angina pectoris and the acute coronary syndromes. Atherosclerosis is a lipoprotein-driven disease that leads to plaque formation at specific sites of the arterial tree through intimal inflammation, necrosis, fibrosis, and calcification. After decades of indolent progression, such plaques may suddenly cause life-threatening coronary thrombosis presenting as an acute coronary syndrome. Most often, the culprit morphology is plaque rupture with exposure of highly thrombogenic, red cell-rich necrotic core material. The permissive structural requirement for this to occur is an extremely thin fibrous cap, and thus, ruptures occur mainly among lesions defined as thin-cap fibroatheromas. Also common are thrombi forming on lesions without rupture (plaque erosion), most often on pathological intimal thickening or fibroatheromas. However, the mechanisms involved in plaque erosion remain largely unknown, although coronary spasm is suspected. The calcified nodule has been suggested as a rare cause of coronary thrombosis in highly calcified and tortious arteries in older individuals. To characterize the severity and prognosis of plaques, several terms are used. Plaque burden denotes the extent of disease, whereas plaque activity is an ambiguous term, which may refer to one of several processes that characterize progression. Plaque vulnerability describes the short-term risk of precipitating symptomatic thrombosis. In this review, we discuss mechanisms of atherosclerotic plaque initiation and progression; how plaques suddenly precipitate life-threatening thrombi; and the concepts of plaque burden, activity, and vulnerability.

Mechanisms of Plaque Formation and Rupture

The embodiments contemplate methods and devices for communicating an acoustic emission via an array of transducers and wirelessly communicating data via a transceiver, where the transceiver may be in communication with the array of transducers. Embodiments also contemplate providing power for the acoustic emission via a power source and providing information regarding a temperature sensor to the transceiver. The wirelessly communicated data may include the information regarding the temperature sensor. Embodiments also contemplate processing the wirelessly communicated data at a relatively remote location with respect to both the power source and the temperature sensor.

Transducer array imaging system

An insertion device and insertion set. The insertion device for inserting at least a portion of at least one piercing member of an insertion set through the skin of a patient includes a device housing, a carrier body and a driver. The carrier body is slidably received within the device housing for movement between an advanced position and a retracted position. The carrier body also includes a receiving structure to support the insertion set in a position with the at least one piercing member oriented for insertion through the skin of the patient at a predetermined angle relative to the skin of the patient upon movement of the carrier body from the retracted position to the advanced position. The driver is operatively coupled between the device housing and the carrier body to urge the carrier body with a controlled force and speed from the retracted position toward the advanced position to place at least a portion of the at least one piercing member of the insertion set thorough the skin of the patient to install the insertion set to the patient. The receiving structure of the carrier body is removable from the insertion set while maintaining the installation of the insertion set to the patient.

Insertion device for an insertion set and method of using the same

The role of vascular biomarkers for primary and secondary prevention. A position paper from the European Society of Cardiology Working Group on peripheral circulation: Endorsed by the Association for Research into Arterial Structure and Physiology (ARTERY) Society.

An ultrasonic probe is moved to scan a volumetric region of the body. As it is moved, targets within the region are interrogated from multiple look directions. The echo data from the multiple look directions are compounded to form spatially compounded image data, which is processed for display in a three dimensional display format.

Spatially compounded three dimensional ultrasonic images

Objectives The purpose of this study was to compare carotid plaque burden, carotid intima-media thickness (cIMT), ankle-brachial index (ABI), and abdominal aortic diameter (AAD) to coronary artery calcium score (CACS) in people without known cardiovascular disease. Background The clinical utility of risk factors to predict cardiovascular events is limited. Detection of subclinical atherosclerosis by noninvasive tests such as CACS, cIMT, carotid plaque burden, AAD, and ABI may improve risk prediction above that of established risk scoring models, namely, Framingham Risk Score. Methods The High Risk Plaque BioImage study investigated 6.101 asymptomatic persons and reports baseline CACS, cIMT, ABI, and AAD. In addition, we present findings from a new 3-dimensional–based ultrasound approach, where the carotid artery was investigated in cross section from proximal in the neck to as distal as possible. From the resulting 10-s video, plaque was outlined on cross-sectional images and all plaque areas were summarized into “plaque burden.” Results The mean age was 68.8 years, and 65.3% of subjects had intermediate Framingham Risk Score (6% to 20% 10-year risk). Carotid plaques were identified in 78% of cases, abnormal ABI in 10%, AAD >20 mm in 28%, and coronary calcium in 68% of participants. Carotid plaque burden was found to correlate stronger with CACS (chi-square 450, p Conclusions In the BioImage study, a new 3-dimensional–based ultrasound method identified more carotid plaques than in previous studies. Compared to other methods, carotid plaque burden was the strongest cross-sectional predictor of CACS, and its clinical utility as predictor of future cardiovascular events is being evaluated in the BioImage study. (BioImage Study: A Clinical Study of Burden of Atherosclerotic Disease in an At-Risk Population; NCT00738725 )

Carotid Plaque Burden as a Measure of Subclinical Atherosclerosis Comparison With Other Tests for Subclinical Arterial Disease in the High Risk Plaque BioImage Study

Real-time spatial compound imaging (SonoCT) is an ultrasound technique that uses electronic beam steering of a transducer array to rapidly acquire several (three to nine) overlapping scans of an object from different view angles These single-angle scans are averaged to form a multiangle compound image that is updated in real time with each subsequent scan Compound imaging shows improved image quality compared with conventional ultrasound, primarily because of reduction of speckle, clutter, and other acoustic artifacts Early clinical experience suggests that real-time spatial compound imaging can provide improved contrast resolution and tissue differentiation that is beneficial for imaging the breast, peripheral blood vessels, and musculoskeletal injuries Future development of real-time spatial compound imaging will help address the bulk of general imaging applications by extending this technology to curved array transducers, tissue harmonics, panoramic imaging, and three-dimensional sonography

Real-time spatial compound imaging : Application to breast, vascular, and musculoskeletal ultrasound

An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Ultrasonic diagnostic imaging transducer with hexagonal patches

An ultrasonic transducer is provided for producing two-dimensional projection images of the interior of the body. The transducer may comprise an array of elements, acuated to produce scanning beams which are focused in the azimuthal direction and divergent in the elevation direction. The elements will, when actuated, emit fan-shaped beams which will insonify a volumetric region in front of the transducer. Echoes returning from structures within the volumetric region are acoustically integrated and projected onto a plane within the region. An image display of this plane will represent a two-dimensional projection of the volumetric region.

Robert R. Entrekin

Papers

Spatially compounded three dimensional ultrasonic images

Carotid Plaque Burden as a Measure of Subclinical Atherosclerosis Comparison With Other Tests for Subclinical Arterial Disease in the High Risk Plaque BioImage Study

Real-time spatial compound imaging : Application to breast, vascular, and musculoskeletal ultrasound

Ultrasonic diagnostic imaging transducer with hexagonal patches

Volumetric ultrasonic imaging with diverging elevational ultrasound beams