ABSTRACT
When a conventional phase-encoding magnetic resonance spectrascopic imaging(MRSI) method is in use, the data acquisition is very time consuming and thus it is not well accepted in clinical settings. Echo planar spectroscopic imaging (EPSI) technology has been applied for rapid acquisition of MRSI data. It significantly reduces scan time by simultaneously encoding the spectral dimension and the spatial dimension. Reconstruction of EPSI data is sophisticated. For the t-dimension, data are non-uniformly sampled. Fast Fourier transform (FFT) is applied in odd echoes and even echoes respectively and then shift method is used to combine them together. For the kx dimension, the data are unevenly sampled and have to be interpolated onto a Cartesian grid before FFT is applied. For the phase-encoding dimension (ky), the Fourier transform can be readily done with FFT since the data are evenly spaced.