博士 / 國立臺灣大學 / 電機工程學研究所 / 102 / Transition into Driven Equilibrium (TIDE) balanced steady-state free precession
(bSSFP) sequence is a variant of bSSFP MRI technique that has been developed over
the last decade. The pulse sequence can be conceptually divided into two parts: a
TIDE preparation and a repetitive constant flip angle readout. The authors of this
thesis independently discovered fat suppression phenomenon during volunteer studies
of TIDE bSSFP, when transient-phase data were sampled and registered at central
k-space. In addition, this imaging method also shows a T2-weighted contrast. To
analyze these specific properties, we used simulations and mathematical deduction to
demonstrate concisely the evolution behaviors of on-resonance spins as well as
certain off-resonance spins. We recruited thirty healthy volunteers to validate the
image quality for TIDE bSSFP for use as an ultrafast multisection T2-weighted image
of the brain. For image quality comparison, turbo spin echo (TSE) and turbo gradient
spin-echo (TGSE) were also used. We also exhibited the differences between
imaging methods on a few patients with brain pathologies. As a result, TIDE bSSFP
provides T2-weighted images with reduced scan times and reduced motion artifact
interference compared with TSE and turbo gradient spin-echo, with the trade-off of
reduced SNR as well as poorer gray-white matter differentiation and iron load
sensitivity. In certain situations like patients with involuntary motions, TIDE bSSFP
technique may serve as a supplement to standard MRI methods.
| Identifer | oai:union.ndltd.org:TW/102NTU05442073 |
| Date | January 2014 |
| Creators | Yin-Cheng Kris Huang, 黃尹宬 |
| Contributors | Te-Son Kuo, 郭德盛 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | en_US |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 79 |
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