Dissertations / Theses on the topic 'Nonlinear ultrasound imaging'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 18 dissertations / theses for your research on the topic 'Nonlinear ultrasound imaging.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Tangen, Thor Andreas. "Imaging of Nonlinear Scattering using Dual-frequency Band Ultrasound." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11493.
Full textYildiz, Yesna. "Nonlinear propagation artefact correction in contrast enhanced ultrasound imaging." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/52435.
Full textVarray, François. "Simulation in nonlinear ultrasound : application to nonlinear parameter imaging in echo mode configuration." Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10165/document.
Full textHarmonic imaging, based on the propagated medium nonlinearity, is a clinical imaging technique which increases the resolution of ultrasound images. The ultrasound measure of the local nonlinear parameter brings new perspectives in term tissues characterization. However, access to this information suffers from two strong points: from one hand, there is no current measurement method of this parameter in echo mode configuration and on the other hand, the simulation tools taking into account the nonlinearity are not many developed. An angular spectrum method has been proposed to compute the nonlinear pressure field with inhomogeneous nonlinear parameter. This pressure field is then used to generate ultrasound images containing the harmonic component. This spectral approach has been implemented on a GPU in order to accelerate the computation and package in a free software made available to the scientific community under the name CREANUIS. In a second time, a extension of a comparative method (ECM) has been proposed to take into account media with inhomogeneous nonlinearity, working an echo mode configuration. Thanks the developed simulation tools, different configurations have been used to parameterize and to evaluate the ECM which has then be validated on test objects and in vitro animal’s livers. Even if the measure presents a relatively weak resolution, the obtained images demonstrated a high potential in the nonlinear parameter imaging of tissues
Høilund-Kaupang, Halvard. "Models and Methods for Investigation of Reverberations in Nonlinear Ultrasound Imaging." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for sirkulasjon og bildediagnostikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15205.
Full textSatir, Sarp. "Modeling and optimization of capacitive micromachined ultrasonic transducers." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54303.
Full textHibbs, Kathryn Jane. "The Effects of Nonlinear Propagation and Dispersion on Quantitative Contrast-Enhanced Ultrasound Imaging." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525343.
Full textPašović, Mirza. "Tissue harmonic reduction : application to ultrasound contrast harmonic imaging." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10060.
Full textUltrasound contrast agents are small micro bubbles that respond nonlinearly when exposed to ultrasound wave. The nonlinear response gives possibility of harmonic ultrasound images which has many advantages over fundamental imaging. However, to increase ultrasound contrast harmonic imaging performance we must first understand nonlinear propagation of ultrasound wave. Nonlinear propagation distorts the propagating wave such that higher harmonics appear as the wave is propagating. The theory that was laid down, was allowed implementing a new method of modelling nonlinear ultrasound propagation. The knowledge obtained during this process was used to construct a multiple component second harmonic reduction signal for reduction of their harmonics generated due to the tissue nonlinearities. As a consequence detection of ultrasound contrast agents at higher harmonics was increased. Further more, a powerful ultrasound imaging technique called Pulse Inversion, was further enhanced with multiple component second harmonic reduction signal. What was learned during investigation of the Pulse Inversion, technique lead to a new phase coded ultrasound contrast harmonic method called second harmonic inversion;. Also it was noted that for different type of media the level of distortion of ultrasound pulse is different. It depends largely on the nonlinear parameter B / A. Although the work on this parameter has not been finished it is very important to continue in this direction since B / A imaging with ultrasound contrast agents has a lot of potential
Narasimha, Reddy Vaka. "Comparison and Optimization of Insonation Strategies for Contrast Enhanced Ultrasound Imaging." Thesis, Linköpings universitet, Biomedicinsk instrumentteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76646.
Full textRobin, Guillaume. "Méthodes acoustiques auto-calibrées en émission - réception pour l'étude et le suivi des propriétés non linéaires des matériaux et l'imagerie." Thesis, Tours, 2011. http://www.theses.fr/2011TOUR3304/document.
Full textUsed in many application areas, ultrasound proved to be sensitive to determine viscoelastic properties. The spatial and temporal investigation of viscoelastic properties of materials by ultrasonic methods can be used to monitor structure integrity and processes. A self-calibrated method, based on reciprocity principle has been developed for measuring the nonlinear parameter B/A. Instrumentation has been development to ensure the rapid determination of the parameter B/A imposing a specific technology. The time evolution of the acoustic parameters of sol-gel materials shows a characteristic time related to the structuration of the material (Arrhnius law). A picture of the nonlinear parameter was performed on a phantom containing two immiscible fluids (water and silicone oil). Through these two examples, the effectiveness of the nonlinear parameter measurements has shown in the follow-up of a material changes as well as imaging
Baggio, André Luis. "Imagens acústicas geradas pela interação da radiação ultrassônica com o meio material." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-04042012-095906/.
Full textIn this work is presented a new modality of elastography images based on the acoustic emission when a material medium was subjected to a ultrasound radiation.This tecnique Nonlinearity behavior of the acoustic wave propagation and the vibrational mechanical response were used to produce images from kilohertz frequencies when the sample was excited by ultrasound waves in megahertz. To produce images with this modality, tissue mimicking phantoms were made with stiffness in homogeneities and subjected a focused ultrasound radiation pulses. The sound emitted due the interaction of the ultrasound wave with the region of interest was recorded and processed in order to associate each small portion of the tissue to a value for image formation. The results showed that this method can produce images associated to the viscoelastic changes of the samples. The spatial resolution have showed strongly linked to the morphology of the excitation acoustic field, this way was possible to detect isolated structures in order of 0.25 mm. The acquisiton technique developed and presented in this work is similar to the vibroacoustography technique, however with reduced instrumentation setup and with the possibility to acquire further information about the structure of the material from the nonlinear phenomenal. Preliminary studies of this new technique and the vibroacoustography were made and compared to evaluate the potential applications, for example, in the evalution of the acoustic signal behavior due changes in the viscoelastic properties changes induced by temperature variations; image formation in the medium with lightly stiffness inclusions; generation of the images of bone structure in vitro.
Lam, Tobin (Toby) Yun Jing. "A pulse-echo model for nonlinear ultrasound imaging." 2007. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=789028&T=F.
Full textPinton, Gianmarco F. "Numerical methods for nonlinear wave propagation in ultrasound." Diss., 2007. http://hdl.handle.net/10161/457.
Full textTOULEMONDE, MATTHIEU EDOUARD GEORGES. "New beamforming strategy for improved ultrasound imaging: application to biological tissues nonlinear imaging." Doctoral thesis, 2014. http://hdl.handle.net/2158/949535.
Full textLu, Sheng-Chieh, and 盧聖介. "Echogenic Liposomes in High-Frequency Ultrasound Imaging and Nonlinear Properties Investigations." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/52078582154250788360.
Full textReznik, Nikita. "Vaporized Perfluorocarbon Droplets as Ultrasound Contrast Agents." Thesis, 2013. http://hdl.handle.net/1807/35939.
Full textChen, Chen-Lin, and 陳震霖. "Nonlinear Analysis of Carotid Artery Distensibility from Transverse and Longitudinal Views of Dynamic Ultrasound Imaging." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/37170567635263544521.
Full text國立中正大學
資訊工程研究所
103
Ministry of Health and Welfare showed that the main cause of death in Taiwan and around the world is cardiovascular disease, and the resulted number of death is increasing. Most cardiovascular diseases are closely related to atherosclerosis. Since the carotid is the main blood supply channel to the brain, its atherosclerosis will cause stroke and is worthy of monitoring. Ultrasound imaging is a cheap and risk-free method to examine the carotid wall for any abnormality. Most methods for estimating the carotid stiffness is to calculate the ratio of lumen diameter (area) and blood pressure between the systolic and diastolic period, but the accuracy and stability would be influenced by many factors. Some studies showed that the stiffness can be assessed by calculating the approximate entropy (ApEn) of that long-term cross section change of carotid. The ApEn and cross-ApEn are nonlinear analysis methods that have been used to analyze many kinds of physiological signals to distinguish abnormality from the normal states. Our goals are two-folded. The first is to verify if the nonlinear analysis results of long term carotid diameter change will be influenced by different image segmentation methods or other factors. The second is to evaluate if the nonlinear analysis can make significant difference between normal and abnormal carotid movements. Our experimental results show that both ApEn and cross-ApEn can make significant difference between normal subjects and carotid atherosclerosis patients, but ApEn will be biased by the heart rate. It works only when the heart rate is normalized before comparisons between groups. Different image segmentation methods will not deviate both entropy calculations.
Christoph, Jan. "Intramural Visualization of Scroll Waves in the Heart." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9642-D.
Full textVenugopal, Mamatha. "A Stochastic Search Approach to Inverse Problems." Thesis, 2016. http://hdl.handle.net/2005/3042.
Full text