Magnetic resonance pulse sequence for EEG activity location and timing

摘要

The switch operated by the patient produces a succession of trigger pulses (T1,T2,...Tn) each followed by several data acquisition phases (DA1-DA6) in a fixed temporal pattern. The waveforms depicted during each phase correspond to a conventional FISP sequence of high-frequency pulses, layer selection gradients, phase encoding gradients, bipolar readout gradients and nuclear magnetic resonance signals read out during the positive part of the latter. The NMR signals are sampled, digitised and fed into a raw data matrix from which a two-dimensional Fourier transform is taken for image reconstruction.