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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

In vivo characterization of ultrasonic backscattering from normal and abnormal lungs

Jafari, Farhad. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 261-265).
132

On optimality and efficiency of parallel magnetic resonance imaging reconstruction challenges and solutions /

Nana, Roger. January 2008 (has links)
Thesis (Ph.D)--Biomedical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Hu, Xiaoping; Committee Member: Keilholz, Shella; Committee Member: Mao, Hui; Committee Member: Martin, Diego; Committee Member: Oshinski, John. Part of the SMARTech Electronic Thesis and Dissertation Collection.
133

Shape reconstruction from volumetric images

Heckenberg, Gregory. Duan, Ye. January 2008 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 12, 2009) Includes bibliographical references.
134

Ultrasonic imaging of flow-induced vibrations in tissue /

Sikdar, Siddhartha. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 237-256).
135

Semi-automated segmentation of 3D medical ultrasound images

Quartararo, John David January 2008 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: 3d ultrasound; ultrasound; image processing; image segmentation; 3d image segmentation; medical imaging Includes bibliographical references (p.142-148).
136

A new modality for microwave tomographic maging : transit time tomography /

Trumbo, Matthew Lee. Marks, Robert J. Jean, B. Randall. January 2006 (has links)
Thesis (M.S.)--Baylor University, 2006. / Includes bibliographical references (p. 56 [i.e. 55]).
137

An inertial-optical tracking system for quantitative, freehand, 3D ultrasound

Goldsmith, Abraham Myron. January 2008 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Freehand; inertial tracking; Ultrasound. Includes bibliographical references (leaves 221-223).
138

Optimisation of vessel-selective magnetic resonance perfusion imaging and angiography

Berry, Eleanor January 2016 (has links)
The diagnosis and treatment of cerebrovascular disease, such as stroke and vascular lesions in the brain, requires knowledge of the status of brain tissue and cerebral arteries. Perfusion imaging and angiography offer information on blood flow to the tissue and through the brain-feeding arteries. A variety of imaging modalities exist to assess brain haemodynamics, including measures of cerebral blood flow and other parameters, however many of these are invasive and/or involve the use of contrast agents toxic to certain patient populations. One non-invasive magnetic resonance imaging alternative for perfusion imaging and angiography, which also provides vessel specific blood flow information, is vessel-encoded pseudocontinuous arterial spin labelling (VEPCASL). VEPCASL uses the blood as an endogenous tracer and can magnetically label the blood from different arteries of interest. The combination of VEPCASL with different imaging strategies can provide a map of the vascular perfusion territories in the brain, or dynamic information on blood flow through the cerebral arteries. The work in this thesis seeks to optimise and develop the encoding process of VEPCASL and accompanying angiographic readouts. Firstly, a rapid and automated method for calculating a minimal number of signal-to-noise ratio (SNR) efficient encodings, for any number and arrangement of vessels, was developed. Its use resulted in improved SNR in perfusion territories fed by more complicated vessel arrangements in the labelling plane. The labelling efficiency of VEPCASL, and its non-vessel-selective equivalent, PCASL, is affected by the presence of magnetic field inhomogeneities in the labelling plane. Consequently, a correction for phase offsets was introduced into the calculation of the optimised encodings. These encodings enabled the recovery of SNR in perfusion territories for PCASL and VEPCASL when phase offsets were present at the labelled arteries. As current VEPCASL angiography methods are relatively slow to acquire, an accelerated readout was developed to acquire two-dimensional vessel-selective dynamic angiograms in approximately one minute. A radial k-space trajectory was found to offer the best vessel definition and SNR. Three-dimensional (3D) angiograms provide the most detailed view of the cerebral vasculature for use in diagnosis and treatment of cerebrovascular disease. A 3D radial readout was optimised to acquire vessel-selective dynamic angiograms. These angiograms offer information on the structure of the vascular tree and how it is fed by the major arteries in the neck. The techniques developed here aim to increase the clinical viability and applicability of VEPCASL perfusion imaging and angiography. It is hoped that the techniques herein could be used in patient populations to add to and improve the diagnostic information available.
139

A visual comparison between the Ultrasound X6-1 Matrix transducer and MRI in lesion detection in the dome of the liver

Subaran, Sarah Samira 22 January 2016 (has links)
Imaging the dome of the liver can be a very challenging area to image by Ultrasound. Due to its position inside the ribcage there can be difficulty with rib shadowing artifacts causing the sonographer to miss small lesions. The X6–1 Matrix transducer is one of the newest of its kind and claims to be the better multi-use transducer. Its larger aperture reduces rib artifacts and is composed of PureWave Crystal Technology. A phantom will serve as a great approach in this abdominal study to visually compare the lesions between MRI (gold standard) and the new X6–1 Matrix Ultrasound transducer. The X6–1 transducers did reveal minimal rib shadowing and the small lesions were identified.
140

Image Processing as Applied to Medical Diagnostics

Thomas, Kristine A. 06 1900 (has links)
xi, 56 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Image processing is a powerful tool for increasing the reliability and reproducibility of disease diagnostics. In the hands of pathologists, image processing provides quantitative data from histological images which supplement the qualitative data currently used by specialists. This thesis presents a novel method for analyzing digitized images of hematoxylin and eosin (H&E) stained histology slides to detect and quantify inflammatory polymorphonuclear leukocytes to aid in the grading of acute inflammation of the placenta as an example of the use of image processing in aid of diagnostics. Methods presented in this thesis include segmentation, a novel threshold selection technique and shape analysis. The most significant contribution is the automated color threshold selection algorithm for H&E stained histology slides which is the only unsupervised method published to date. / Committee in charge: Dr. John Conery, Chair; Dr. Matthew J. Sottile

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