dc.contributor.advisor |
Nash, Martyn P. |
en |
dc.contributor.advisor |
Nielsen, Poul M.F. |
en |
dc.contributor.author |
Chung, Jae-Hoon |
en |
dc.date.accessioned |
2020-06-02T04:37:23Z |
en |
dc.date.available |
2020-06-02T04:37:23Z |
en |
dc.date.issued |
2008 |
en |
dc.identifier.uri |
http://hdl.handle.net/2292/51056 |
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dc.description |
Full text is available to authenticated members of The University of Auckland only. |
en |
dc.description.abstract |
This thesis presents research on the development and validation of a 3D biomechanical model of the breast subject to mammographic compressions. The model was motivated by difficulties with tracking tumours identified from 2 D X-ray mammograms to the 3 D breast volume. In order to model large compressive deformations, the theory of finite elasticity coupled with contact mechanics was implemented using the finite element method (FEM). In particular, frictional contact based on Coulomb's law and using a C1-continuous Hermite mesh was implemented by modifying the classical node-to-surface approach. A carefully controlled experimental validation study was then conducted in order to test the developed modelling framework. A homogeneous silicon gel phantom ( roughly representing the shape and size of human female breast) was applied with two mammographic-like compressions. Magnetic Resonance Imaging ( MRI) was used to quantify the surface deformations and locations of 4 embedded internal markers of the gel phantom under compressions. These deformed data were used to validate modelling predictions. The surface rootmean- square errors ( RMSE) were less than 2 mm and Euclidian errors for tracking the locations of internal markers were less than 3 mm for both compression modes. The modelling framework was applied to a set of clinical MR images of a volunteer's left breast. Compression was applied to the breast in the lateromedial direction using compression pads in the breast coil. A FE model was then constructed based on images from the uncompressed breast and used as the reference state for compression simulations. Model predictions of the compressed surface deformation resulted in a RMSE of 1.54 mm. The locations of three identifiable internal features were tracked to within 4.1 mm to 6.5 mm. Avenues for further numerical developments and experimental validations in order to create more realistic models of the breast were also addressed. This modelling framework will be useful for tracking visible tumours between mammograms, as well as for registering breast images taken from different imaging modalities. |
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dc.publisher |
ResearchSpace@Auckland |
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dc.relation.ispartof |
PhD Thesis - University of Auckland |
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dc.relation.isreferencedby |
UoA99179338714002091 |
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dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. |
en |
dc.rights |
Restricted Item. Full text is available to authenticated members of The University of Auckland only. |
en |
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
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dc.title |
Modelling mammographic mechanics |
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dc.type |
Thesis |
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thesis.degree.discipline |
Bioengineering |
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thesis.degree.grantor |
The University of Auckland |
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thesis.degree.level |
Doctoral |
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thesis.degree.name |
PhD |
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dc.rights.holder |
Copyright: The author |
en |
dc.identifier.wikidata |
Q112877200 |
|