Type
Text
Type
Dissertation
Advisor
Button, Terry | Vaska, Paul | Schlyer, David | Woody, Craig.
Date
2015-12-01
Keywords
Biomedical engineering | GEM, MRI, Neutron, Nuclear imaging, PET, preclinical
Department
Department of Biomedical Engineering.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76989
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Biological systems are incredibly complex and their scientific study can be facilitated by the assessment of multiple independent parameters from the same location, ideally in way that provides quantitative and time-synchronized data, with high spatial sampling, and throughout a living subject. Our group has advanced this in vivo, quantitative, multimodal imaging approach by developing and combining various nuclear imaging modalities that provide complementary data to better understand the physiology of humans, animal models, and even plants. Multi-modality imaging in clinical and pre-clinical settings has been shown to provide better diagnostic interpretation compared to stand-alone imaging systems. In recent years, combining PET and MRI together has opened a new area of imaging technology compared with well-established PET-CT because of the inherently different imaging contrast mechanism of MRI compared with CT. At Brookhaven National Laboratory, a PET system has been developed for the purpose of simultaneous PET-MRI whole rodent imaging in conjunction with a Varian large-bore 9.4T MRI system with a commercial Insight birdcage coil. The main aims of the dissertation include developing hardware and software for this new PET system, evaluating the system performance and investigating the system under scenarios of meaningful preclinical studies. Positron Emission Tomography can also be used to study plant biology. However, since some important structures found on plants (e.g, leaves) are very thin, a large portion of the positrons emitted from PET isotopes escape before annihilation, leading to low efficiency and quantification inaccuracies. A gas tracking detector is developed here to measure escaping positrons from PET radiotracer isotopes which has the ability to reconstruct three dimensional tracks that can be used to form an image of the emitting object. This device uses a triple GEM detector with a short drift region and an XY strip readout plane to measure a vector for positrons passing through a drift gap. By projecting each particle track back to the object surface, a 2-D image of the spatial distribution of the positrons that escaped from that surface can be reconstructed. We describe the basic principle of the GEM detector and present results on its performance using various types of phantoms and actual plant specimens. Monte Carlo simulations are also used to better understand the detector performance and compare to actual measurements. Finally, I performed a simulation study of a new nuclear imaging method that can provide quantitative imaging data on elemental composition within the human body. Such information is currently measurable only via biopsy, and a non-invasive measure could have far-ranging benefits from nutrition to cancer diagnosis, especially if assessed in conjunction with other imaging modalities such as PET and MRI. The method involves inelastic neutron scattering and it shares many parallels to modern forms of PET, including the concepts of line-of-response and time-of-flight. My analysis shows that the approach is very promising, achieving quantitative measures of heavy elements with acceptable radiation dose to the patient. | 109 pages
Recommended Citation
Cao, Tuoyu, "Development of Novel Nuclear Imaging Systems for Bioscience Applications" (2015). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2854.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2854