Abstract
A new periodic pulse sequence employing weak excitation is presented. This type of sequence drives the system into a steady-state with periodic time evolution from which the data can be reconstructed to a spectrum. It is demonstrated that the frequency response of such a sequence can be analyzed using perturbation methods and linear system analysis. A mathematical framework is proposed allowing the frequency response to be tailored by weighting a periodic flip function. The weak excitation level used implies very low specific absorption rates while generating a highly frequency selective signal in the order of 1/T2 with signal strengths comparable to those obtainable with conventional large flip angle balanced steady-state free precession techniques. The concept is illustrated with phantom experiments and in vivo feasibility of water fat separation is shown on human knee images.
Original language | English (US) |
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Pages (from-to) | 142-154 |
Number of pages | 13 |
Journal | Journal of Magnetic Resonance |
Volume | 178 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2006 |
Externally published | Yes |
Keywords
- Frequency-selective imaging
- Rapid imaging
- Small flip angle
- Specific absorption rate
- Steady-state free precession
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Nuclear and High Energy Physics
- Condensed Matter Physics