{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/97333"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/97333","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Reconstruction of spatially varying sound speed distributions from pulse-echo data","abstract":"Traditional ultrasonic brightness mode (B-Mode) images are plagued by poor image quality due to the limited observational coverage. This has motivated research in alternative imaging modes, such as tomographic reconstruction of sound speed distributions. Historically, sound speed tomography has typically been performed in transmission-mode, which requires specialized hardware configurations and is limited to acoustically transparent tissue such as the female breast. For this reason, integration of sound speed tomography in medical settings has been slow. Recent results from Jaeger et al. (2015) have demonstrated that sound speed tomography can be performed in pulse-echo mode by exploiting cross-correlations of post-beamformed data acquired from multiple steered plane wave excitations. Unlike traditional sound speed tomography setups, pulse-echo sound speed tomography only requires a single linear array transducer, which is commonly available in a clinical setting. While the evidence presented in Jaeger et al. (2015) is exciting, the theoretical analysis in that result was lacking. In particular, no attempt was given to characterize the spatial Fourier coverage of the underlying correlation measurements. Furthermore, Jaeger's simulation results were not realistic, as they neglected heterogeneous distortions to the point spread functions due to refraction. In this work, we attempt to address these oversights. This thesis is organized as follows. To begin, the fundamentals of pulse echo sound speed tomography are reviewed. Second, the underlying model is reformulated as a convolutional model. Using this convolutional model, the spatial Fourier coverage of pulse-echo sound speed tomography is derived and shown to be complementary to that of standard B-Mode and diffraction tomography. Finally a simulation study is conducted utilizing the simulation package k-Wave~to evaluate the degeneration due to refraction.","abstract_html":"Traditional ultrasonic brightness mode (B-Mode) images are plagued by poor image quality due to the limited observational coverage. This has motivated research in alternative imaging modes, such as tomographic reconstruction of sound speed distributions. Historically, sound speed tomography has typically been performed in transmission-mode, which requires specialized hardware configurations and is limited to acoustically transparent tissue such as the female breast. For this reason, integration of sound speed tomography in medical settings has been slow. Recent results from Jaeger et al. (2015) have demonstrated that sound speed tomography can be performed in pulse-echo mode by exploiting cross-correlations of post-beamformed data acquired from multiple steered plane wave excitations. Unlike traditional sound speed tomography setups, pulse-echo sound speed tomography only requires a single linear array transducer, which is commonly available in a clinical setting. While the evidence presented in Jaeger et al. (2015) is exciting, the theoretical analysis in that result was lacking. In particular, no attempt was given to characterize the spatial Fourier coverage of the underlying correlation measurements. Furthermore, Jaeger's simulation results were not realistic, as they neglected heterogeneous distortions to the point spread functions due to refraction. In this work, we attempt to address these oversights. This thesis is organized as follows. To begin, the fundamentals of pulse echo sound speed tomography are reviewed. Second, the underlying model is reformulated as a convolutional model. Using this convolutional model, the spatial Fourier coverage of pulse-echo sound speed tomography is derived and shown to be complementary to that of standard B-Mode and diffraction tomography. Finally a simulation study is conducted utilizing the simulation package k-Wave~to evaluate the degeneration due to refraction.","abstract_has_math":false,"creators":["Podkowa, Anthony S"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Electrical & Computer Engr","degree_department":null,"school":null,"contributors":["Oelze, Michael L."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2017,"date_issued":"2017-08-10T19:14:54Z","date_published":"2017-08-10T19:14:54Z","updated_at":"2026-07-22T22:24:32Z","subjects":["Ultrasound","Tomography","Sound speed","Pulse-echo"],"languages":["en"],"rights":["Copyright 2017 Anthony S. Podkowa"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/97333","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Oelze, Michael L."]},{"key":"dc:creator","label":"Author","values":["Podkowa, Anthony S"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2017-08-10T19:14:54Z","2017-04-13","2017-05"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical & Computer Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Ultrasound","Tomography","Sound speed","Pulse-echo"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2017 Anthony S. Podkowa"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/97333"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Traditional ultrasonic brightness mode (B-Mode) images are plagued by poor image quality due to the limited observational coverage. This has motivated research in alternative imaging modes, such as tomographic reconstruction of sound speed distributions. Historically, sound speed tomography has typically been performed in transmission-mode, which requires specialized hardware configurations and is limited to acoustically transparent tissue such as the female breast. For this reason, integration of sound speed tomography in medical settings has been slow. Recent results from Jaeger et al. (2015) have demonstrated that sound speed tomography can be performed in pulse-echo mode by exploiting cross-correlations of post-beamformed data acquired from multiple steered plane wave excitations. Unlike traditional sound speed tomography setups, pulse-echo sound speed tomography only requires a single linear array transducer, which is commonly available in a clinical setting. While the evidence presented in Jaeger et al. (2015) is exciting, the theoretical analysis in that result was lacking. In particular, no attempt was given to characterize the spatial Fourier coverage of the underlying correlation measurements. Furthermore, Jaeger's simulation results were not realistic, as they neglected heterogeneous distortions to the point spread functions due to refraction. In this work, we attempt to address these oversights. This thesis is organized as follows. To begin, the fundamentals of pulse echo sound speed tomography are reviewed. Second, the underlying model is reformulated as a convolutional model. Using this convolutional model, the spatial Fourier coverage of pulse-echo sound speed tomography is derived and shown to be complementary to that of standard B-Mode and diffraction tomography. Finally a simulation study is conducted utilizing the simulation package k-Wave~to evaluate the degeneration due to refraction.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2017-08-10 without embargo terms","The student, Anthony Podkowa, accepted the attached license on 2017-04-11 at 16:29.","The student, Anthony Podkowa, submitted this Thesis for approval on 2017-04-11 at 16:40.","This Thesis was approved for publication on 2017-04-13 at 11:53.","DSpace SAF Submission Ingestion Package generated from Vireo submission #10706 on 2017-08-10 at 13:39:22","Made available in DSpace on 2017-08-10T19:14:54Z (GMT). No. of bitstreams: 2 PODKOWA-THESIS-2017.pdf: 551541 bytes, checksum: a09dd66a0ea8d67da6549ab069867847 (MD5) LICENSE.txt: 4212 bytes, checksum: bd979283e6ffd99eda42364bee2def9f (MD5) Previous issue date: 2017-04-13"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Reconstruction of spatially varying sound speed distributions from pulse-echo data"]}]}],"canonical_facts":{"dc:contributor":["Oelze, Michael L."],"dc:creator":["Podkowa, Anthony S"],"dc:date":["2017-08-10T19:14:54Z","2017-04-13","2017-05"],"dc:description":["Traditional ultrasonic brightness mode (B-Mode) images are plagued by poor image quality due to the limited observational coverage. This has motivated research in alternative imaging modes, such as tomographic reconstruction of sound speed distributions. Historically, sound speed tomography has typically been performed in transmission-mode, which requires specialized hardware configurations and is limited to acoustically transparent tissue such as the female breast. For this reason, integration of sound speed tomography in medical settings has been slow. Recent results from Jaeger et al. (2015) have demonstrated that sound speed tomography can be performed in pulse-echo mode by exploiting cross-correlations of post-beamformed data acquired from multiple steered plane wave excitations. Unlike traditional sound speed tomography setups, pulse-echo sound speed tomography only requires a single linear array transducer, which is commonly available in a clinical setting. While the evidence presented in Jaeger et al. (2015) is exciting, the theoretical analysis in that result was lacking. In particular, no attempt was given to characterize the spatial Fourier coverage of the underlying correlation measurements. Furthermore, Jaeger's simulation results were not realistic, as they neglected heterogeneous distortions to the point spread functions due to refraction. In this work, we attempt to address these oversights. This thesis is organized as follows. To begin, the fundamentals of pulse echo sound speed tomography are reviewed. Second, the underlying model is reformulated as a convolutional model. Using this convolutional model, the spatial Fourier coverage of pulse-echo sound speed tomography is derived and shown to be complementary to that of standard B-Mode and diffraction tomography. Finally a simulation study is conducted utilizing the simulation package k-Wave~to evaluate the degeneration due to refraction.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2017-08-10 without embargo terms","The student, Anthony Podkowa, accepted the attached license on 2017-04-11 at 16:29.","The student, Anthony Podkowa, submitted this Thesis for approval on 2017-04-11 at 16:40.","This Thesis was approved for publication on 2017-04-13 at 11:53.","DSpace SAF Submission Ingestion Package generated from Vireo submission #10706 on 2017-08-10 at 13:39:22","Made available in DSpace on 2017-08-10T19:14:54Z (GMT). No. of bitstreams: 2 PODKOWA-THESIS-2017.pdf: 551541 bytes, checksum: a09dd66a0ea8d67da6549ab069867847 (MD5) LICENSE.txt: 4212 bytes, checksum: bd979283e6ffd99eda42364bee2def9f (MD5) Previous issue date: 2017-04-13"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/97333"],"dc:language":["en"],"dc:rights":["Copyright 2017 Anthony S. Podkowa"],"dc:subject":["Ultrasound","Tomography","Sound speed","Pulse-echo"],"dc:title":["Reconstruction of spatially varying sound speed distributions from pulse-echo data"],"dc:type":["text"],"thesis:degree_discipline":["Electrical & Computer Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:32Z"}