Tissue biomechanics plays a powerful and pervasive role in health and disease. However, accurate analysis of tissue requires high resolution, non-contact assessments of mechanical behavior during physiologic loading. Optical imaging techniques are particularly apt for this purpose, as optical imaging allows for high resolution, non-invasive imaging with endogenous contrast.
Two new methods using optical imaging and image processing were developed and used in vivo and in vitro. Optical coherence tomography based wall motion analysis (OCT-WMA) analyzes the deformation of a lumen during pulsatile inflation. High strain-rate dependence is expected in many biomaterials: by analyzing behavior during physiologic loading, this technique offers new insight into in vivo mechanical behavior. OCT-WMA was used to assess airway behavior in a rabbit model of fibrotic airway injury during tidal breathing. Increased tissue compliance was observed with increased mucosal thickness suggesting that injury affects airway biomechanics. Additionally, it was used in vitro in a cadaveric arterial prep to diagnose arterial plaque type. In native geometry under physiological loading, vulnerable plaques are more compliant than their embedding tissue. This technique has high potential for clinical translation.
The second technique developed, generalized image correlation spectroscopy of multiphoton images uses autocorrelation to detect fluorophore alignment at multiple spatial scales. This technique was used to detect tissue prestress in tissue engineered collagen gels; fiber alignment at the cell scale distinguished between stressed and unstressed gels.
These two techniques both use non-destructive optical imaging and image processing to assess tissue biomechanics.
|Advisor:||George, Steven C.|
|Commitee:||Botvinik, Elliot, Brenner, Matthew|
|School:||University of California, Irvine|
|Department:||Biomedical Engineering - Ph.D.|
|School Location:||United States -- California|
|Source:||DAI-B 74/10(E), Dissertation Abstracts International|
|Subjects:||Biomedical engineering, Biomechanics|
|Keywords:||Image processing, Optical imaging, Tissue compliance, Wall motion analysis|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be