Multi-Echo Spin Echo MRI Signal Modulation Based on Slice Profiles

Standing

Graduate (Masters)

Type of Proposal

Poster Presentation

Challenges Theme

Building Viable, Healthy and Safe Communities

Your Location

University of Windsor

Faculty

Faculty of Science

Faculty Sponsor

Dan Xiao

Proposal

Magnetic Resonance Imaging (MRI) is a non-invasive imaging modality in which magnetic pulses are used to excite and produce signals from hydrogen nuclei in a target sample. The excitation produces a signal with a certain lifetime that is dependent on the molecular environments and structures around the hydrogen nuclei. In qualitative images, differences in the lifetime of a signal and proton density produce contrast to distinguish healthy tissue and tumours. In imaging experiments, a magnetic pulse coupled with a magnetic field gradient selects a desired cross-section (slice profile) of the hydrogen nuclei in the sample. The Multi-Echo Spin Echo (MESE) experiment is designed to isolate the signal lifetimes to construct a numerical map that is sensitive to features normally hidden by the combined weight of other parameters in a qualitative image. The data acquired by the MESE is fit to a decaying exponential function, where the calculated decay constant is the signal lifetime. However, in the case of non-ideal slice profiles, the data deviates from an exponential decay, which introduces error in the parameter calculation. This effect has been simulated numerically with various pulse types and verified in phantom measurements. The goal is to use the simulations to identify and correct improper fitting results for more accurate mapping. This can be used for analysis of disease progression to detect changes not typically detected via conventional imaging techniques.

Share

COinS
 

Multi-Echo Spin Echo MRI Signal Modulation Based on Slice Profiles

Magnetic Resonance Imaging (MRI) is a non-invasive imaging modality in which magnetic pulses are used to excite and produce signals from hydrogen nuclei in a target sample. The excitation produces a signal with a certain lifetime that is dependent on the molecular environments and structures around the hydrogen nuclei. In qualitative images, differences in the lifetime of a signal and proton density produce contrast to distinguish healthy tissue and tumours. In imaging experiments, a magnetic pulse coupled with a magnetic field gradient selects a desired cross-section (slice profile) of the hydrogen nuclei in the sample. The Multi-Echo Spin Echo (MESE) experiment is designed to isolate the signal lifetimes to construct a numerical map that is sensitive to features normally hidden by the combined weight of other parameters in a qualitative image. The data acquired by the MESE is fit to a decaying exponential function, where the calculated decay constant is the signal lifetime. However, in the case of non-ideal slice profiles, the data deviates from an exponential decay, which introduces error in the parameter calculation. This effect has been simulated numerically with various pulse types and verified in phantom measurements. The goal is to use the simulations to identify and correct improper fitting results for more accurate mapping. This can be used for analysis of disease progression to detect changes not typically detected via conventional imaging techniques.