The main objective of this master’s thesis is to investigate the possibility of applying spatially-filtered continuous-wave acoustic tomography to the detection of breast cancer. A continuous acoustic wave is transmitted through the specimen in this tomographic imaging method. Any scattered waves that do not positively contribute to the projection are filtered out using an aperture. There is evidence to suggest that cancerous lesions in the breast have a higher speed of sound than surrounding tissues. This imaging method produces two tomograms of the specimen simultaneously: one showing the internal speed of sound, and the other showing the internal acoustic attenuation coefficient. There is the possibility for a third imaging modality, acoustic dispersion tomography, to be applied to this imaging method.
Two proof-of-concept prototype spatially-filtered continuous-wave acoustic tomography scanners were designed and built: one that uses a collimated beam to interrogate the specimen, and another that uses a confocal beam. A least-squares tomographic reconstruction algorithm was chosen to reconstruct the tomograms this method creates. A prostate phantom and a breast phantom were imaged with the confocal tomographic scanner. The tomograms of the prostate phantom show two 1 cm lesions which are consistent with information from the phantom manufacturer. Further work is required to properly validate the speed of sound and acoustic attenuation measurements this method produces. / Graduate
| Identifer | oai:union.ndltd.org:uvic.ca/oai:dspace.library.uvic.ca:1828/4423 |
| Date | 15 January 2013 |
| Creators | McCaugherty, Kevin |
| Contributors | Herring, Rodney A. |
| Source Sets | University of Victoria |
| Language | English, English |
| Detected Language | English |
| Type | Thesis |
| Rights | Available to the World Wide Web |
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