Searched for: subject%3A%22ultrasound%255C+imaging%22
(1 - 20 of 53)

Pages

document
Wemelsfelder, Tom (author)
In recent years, many therapeutic applications for medical ultrasound have arisen, such as ablation of tumors, breaking up kidney stones, and neuromodulation. To localize the target area, often ultrasound imaging methods are used. Conventionally, a different transducer array is used for imaging and therapeutic applications because of their...
master thesis 2024
document
Moisello, Elisabetta (author), Novaresi, Lara (author), Eshani Sarkar, E. (author), Malcovati, Piero (author), Lopes Marta da Costa, T.M. (author), Bonizzoni, Edoardo (author)
Piezoelectric Micromachined Ultrasonic Transducers (PMUT) and Capacitive Micromachined Ultrasonic Transducers (CMUT) have seen great developments in recent years, both in terms of performance and scope of applications within the biomedical ultrasound domain. This paper presents a review of the state-of-the-art of PMUT and CMUT technologies,...
review 2024
document
Bellouki, Imad (author)
This work presents an ASIC designed for portable (wearable) ultrasound (US) imaging systems. The ASIC employs a new type of energy-efficient high-voltage (HV) transmit pulser able to generate pulses up to 30V directly from a low-voltage battery supply to excite an ultrasound transducer. HV operation is a necessity in US imaging transceiver...
master thesis 2023
document
Dai, Jie (author)
In ultrasound imaging systems, a charge-sharing successive-approximation-register (SAR) ADC has benefits over a charge-redistribution SAR because the charge-sharing SAR is organically compatible with the subarray beamformer which is deployed to reduce the large channel count. Besides, the noise-shaping (NS) SAR is a promising candidate for...
master thesis 2023
document
ZHU, LEXI (author)
Doppler ultrasound imaging of cerebral blood flow faces challenges arising from a low signal-to-noise ratio (SNR) and a wide dynamic range. Echo signals received from blood cells are significantly weaker compared to surrounding tissues, such as the skull or brain soft tissue, resulting in inhibited visualization of small blood vessels and deep...
master thesis 2023
document
De Carlo, Francesca (author)
Ultrasound images are typically generated using the Delay-And-Sum (DAS) method, which assumes a homogeneous propagation medium. When an aberrating layer is situated between the sensor array and the imaging target, this assumption does not hold, and DAS is replaced with model-based methods. These methods are computationally expensive and require...
master thesis 2023
document
Gao, Xuan (author)
Micro-Doppler (µDoppler) ultrasound imaging is a high frame rate ultrasound imaging modality that provides high spatiotemporal resolution ultrasound images of blood flow. It is sensitive to slow blood flow and particularly suitable for capturing fast-changing phenomena like rapid blood flow. Clutter filtering is an essential step in µDoppler...
master thesis 2023
document
van der Meulen, P.Q. (author)
Whereas aberrating layers are typically viewed as an impediment to medical ultrasound imaging, they can, surprisingly, also be used to our benefit. As long as we can model the effect of an aberrating layer, we can utilize ‘model-based imaging’, the imaging technique explored throughout this thesis, to reconstruct ultrasound images where...
doctoral thesis 2023
document
Dia, Amadou Sall (author), Renaud, G.G.J. (author), Nooghabi, Aida Hejazi (author), Grimal, Quentin (author)
Decreased thickness of the bone cortex due to bone loss in the course of ageing and osteoporosis is associated with reduced bone strength. Cortical thickness measurement from ultrasound images was recently demonstrated in young adults. This requires the identification of both the outer (periosteum) and inner (endosteum) surfaces of the bone...
journal article 2023
document
Dash, A. (author)
Suspensions are of interest for curiosity-driven as well as applied research. From a fundamental perspective, inertia of the particles or the system triggers different behaviour in suspension flows. From an experimental perspective, analyzing suspensions is challenging due to their inherent opacity. This dissertation details the author's...
doctoral thesis 2022
document
de Jong, Jan (author)
Functional ultrasound is by now a well-established technique in the neuroscience community to measure brain activity. However, the transcranial application of functional ultrasound on humans, with the exception of the acoustic windows in the skull, remains a huge challenge because of the properties of the cranial bone the acoustic waves will...
master thesis 2022
document
Mozaffarzadeh, M. (author), Verweij, M.D. (author), de Jong, N. (author), Renaud, G.G.J. (author)
While transcranial ultrasound imaging is a promising diagnostic modality, it is still hindered due to phase aberration and multiple scattering caused by the skull. In this paper, we compare near-field phase-screen modeling (PS) to a geometry-based phase aberration correction technique (GB) when an ultrafast imaging sequence (five plane waves...
journal article 2022
document
Guo, P. (author), Chang, Z.Y. (author), Noothout, E.C. (author), Vos, H.J. (author), Bosch, Johan G. (author), de Jong, N. (author), Verweij, M.D. (author), Pertijs, M.A.P. (author)
This article presents a compact analog front-end (AFE) circuit for ultrasound receivers with linear-in-dB continuous gain control for time-gain compensation (TGC). The AFE consists of two variable-gain stages, both of which employ a novel complementary current-steering network (CCSN) as the interpolator to realize continuously variable gain....
journal article 2022
document
Soozande, Mehdi (author), Ossenkoppele, B.W. (author), Hopf, Y.M. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author), de Jong, N. (author), Vos, H.J. (author), Bosch, Johan G. (author)
Atrial fibrillation (AF) is the most common cardiac arrhythmia and is normally treated by RF ablation. Intracardiac echography (ICE) is widely employed during RF ablation procedures to guide the electrophysiologist in navigating the ablation catheter, although only 2-D probes are currently clinically used. A 3-D ICE catheter would not only...
journal article 2022
document
Renaud, G.G.J. (author), Salles, Sébastien (author)
In this chapter, we first review the reasons why conventional ultrasonography fails to image the interior of bones. Next we show our recent work on imaging a cortical bone layer with ultrasound. Revealing the shape of the cortex of a bone, in particular its thickness, is of interest for evaluating bone strength. In addition we describe how...
journal article 2022
document
Ramirez, Ana B. (author), Abreo, Sergio A. (author), van Dongen, K.W.A. (author)
With full waveform inversion (FWI) all available information enclosed in the recorded wavefield - including multiple scattering, dispersion, and diffraction - is used to obtain accurate images showing quantitative information of the tissue parameters. These non-linear inversion methods are implemented either in the time or in the frequency...
conference paper 2022
document
Mozaffarzadeh, M. (author), Verschuur, D.J. (author), Verweij, M.D. (author), Daeichin, V. (author), de Jong, N. (author), Renaud, G.G.J. (author)
Transcranial ultrasound imaging (TUI) is a diagnostic modality with numerous applications, but unfortunately, it is hindered by phase aberration caused by the skull. In this article, we propose to reconstruct a transcranial B-mode image with a refraction-corrected synthetic aperture imaging (SAI) scheme. First, the compressional sound...
journal article 2022
document
Simoes dos Santos, D. (author), Fool, F. (author), Mozaffarzadeh, M. (author), Shabanimotlagh, M. (author), Noothout, E.C. (author), Kim, T. (author), Rozsa, N.N.M. (author), Vos, H.J. (author), Bosch, Johan G. (author), Pertijs, M.A.P. (author), Verweij, M.D. (author), de Jong, N. (author)
High frame rate three-dimensional (3D) ultrasound imaging would offer excellent possibilities for the accurate assessment of carotid artery diseases. This calls for a matrix transducer with a large aperture and a vast number of elements. Such a matrix transducer should be interfaced with an application-specific integrated circuit (ASIC) for...
journal article 2022
document
Koele, Berend (author)
Vagus nerve stimulation (VNS) has been proven to be an effective treatment for patients suffering from drug­-resistant epilepsy. Current vagus nerve stimulators are either implantable devices or bulky, handheld devices. The implant consists of a pulse generator beneath the skin of the chest, connected to electrodes that are wired to the cervical...
master thesis 2021
document
Xing, Jianing (author)
This thesis discusses the architecture, circuit implementation and simulation results of an amplitude-tunable bipolar high voltage (HV) pulser for ultrasound imaging. This design is capable of providing a relatively high-resolution amplitude modulation and allows bipolar pulsing under a unipolar supply with a small die size.<br/>The pulser...
master thesis 2021
Searched for: subject%3A%22ultrasound%255C+imaging%22
(1 - 20 of 53)

Pages