| 摘要 |
Through advancing the phase of radio frequency (RF) excitation with each phase-encoding level, a method, apparatus and article thereof increases the effectiveness of a Magnetic Resonance Imaging (MRI) device by correcting for main magnetic field inhomogeneities without noticeably decreasing the signal-to-noise (SNR) ratio. Increased effectiveness of fast imaging with steady precession (FISP) scans and using FISP scans to image multiple slices. In an MRI device, a patient is subjected to a constant magnetic field, and RF pulses are used to excite the nuclei in the patient's body, which release a corresponding RF signal as the nuclei relax, which is measured and mapped into a visual display. The RF pulses used to excite the nuclei cooperate with a slice select gradient and a phase-encoding gradient. When the RF pulse is phase shifted with each phase-encoding gradient level, improved SNR ratios are observed. |
