Show simple item record

dc.contributor.advisor Trahey, Gregg E. en_US
dc.contributor.author Lediju Bell, Muyinatu A. en_US
dc.date.accessioned 2012-09-04T13:14:38Z
dc.date.available 2012-09-04T13:14:38Z
dc.date.issued 2012 en_US
dc.identifier.uri http://hdl.handle.net/10161/5762
dc.description Dissertation en_US
dc.description.abstract <p>Clutter is a problematic noise artifact in a variety of ultrasound applications. Clinical tasks complicated by the presence of clutter include detecting cancerous lesions in abdominal organs (e.g. livers, bladders) and visualizing endocardial borders to assess cardiovascular health. In this dissertation, an analytical expression for contrast loss due to clutter is derived, clutter is quantified in abdominal images, and sources of abdominal clutter are identified. Novel clutter reduction methods are also presented and tested in abdominal and cardiac images. </p><p>One of the novel clutter reduction methods is Short-Lag Spatial Coherence (SLSC) imaging. Instead of applying a conventional delay-and-sum beamformer to measure the amplitude of received echoes and form B-mode images, the spatial coherence of received echoes are measured to form SLSC images. The world's first SLSC images of simulated, phantom, and <italic>in vivo</italic> data are presented herein. They demonstrate reduced clutter and improved contrast, contrast-to-noise, and signal-to-noise ratios compared to conventional B-mode images. In addition, the resolution characteristics of SLSC images are quantified and compared to resolution in B-mode images. </p><p>A clinical study with 14 volunteers was conducted to demonstrate that SLSC imaging offers 19-33% improvement in the visualization of endocardial borders when the quality of B-mode images formed from the same echo data was poor. There were no statistically significant improvements in endocardial border visualization with SLSC imaging when the quality of matched B-mode images was medium to good.</p> en_US
dc.subject Biomedical engineering en_US
dc.subject abdominal imaging en_US
dc.subject clutter reduction en_US
dc.subject contrast en_US
dc.subject echocardiography en_US
dc.subject resolution en_US
dc.subject ultrasound en_US
dc.title Improved Endocardial Border Definition with Short-Lag Spatial Coherence (SLSC) Imaging en_US
dc.type Dissertation en_US
dc.department Biomedical Engineering en_US

Files in this item

This item appears in the following Collection(s)

Show simple item record