The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
To acquire reliable medical ultrasound images and accurately detect vascular diseases, it is inevitable to improve axial resolution and contrast facilitating clearly definition of depth and thickness of blood vessel walls.
In this paper, we propose the frequency domain minimum variance (MV) method plus coherence factor (CF) weighting technique to improve the axial resolution of medical ultrasound images. The minimum variance beamformer is originally proposed to apply over aperture domain data to improve lateral resolution. Via the help of spectral whitening, the MV method can be applied to the frequency components which...
To avoid large grating lobes, using a small element-to-element pitch of ultrasound array transducers for photoacoustic (PA) imaging is necessary. Such constraint introduces higher system cost and complexity, especially when greater than 20-MHz high-frequency arrays are used. As a result, to reduce fabrication difficulties and obtain better signal sensitivity in PA imaging, ultrasound linear array...
In this paper, we study the problem of ultrasound image segmentation of kidney images. We propose a new region based active contour algorithm. The energy function of our algorithm is based on Chan-Vese energy function and the Bhattacharyya distance. In our framework, a curve is evolved to partition the image into two parts. Our algorithm minimizes the differences between each part and maximizes the...
Using high intensity focused ultrasound (HIFU) to locally perform thermal ablation has shown its potential in auxiliary excision surgery, especially in thermal ablation of tumor. However, it is challenging for clinical physicians to locate the region being under HIFU thermal ablation and determine the applied ablation level only by conventional ultrasound B-mode images, causing dangers in therapy...
Sidelobe contribution from off-axis scatterers degrades image quality in ultrasound imaging. Focusing errors resulting from sound-velocity inhomogeneities in tissues, also known as phase aberrations, reduce coherence of the received signals and thus elevates the sidelobe level degrading the contrast resolution. In this study, we proposed a novel adaptive sidelobe-reduction technique using aperture...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.