Patent ID: 7411394
Filing Date: 2008-08-12
Classification: G01R

Abstract:
1. A method for measuring intravoxel molecule diffusion gradient of spins in a specimen in a selected direction using an MRI system which comprises: (a) utilizing diffusion-encoding magnetic gradient pulses in an MRI pulse sequence to encode diffusion into MR signals; (b) applying diffusion-encoding gradient pulses in a selected direction to yield diffusion-weighted MR signals; (c) applying no diffusion-encoding gradient pulses to yield MR signals without diffusion-weighting; (d) demodulating the received MR signals to I and Q channel filtered signals; (e) reconstructing I and Q images from the I and Q signals using a simple two-dimensional Fourier transformation; (f) computing diffusion-weighted and diffusion-free phase images from their corresponding I and Q images; (g) computing the phase difference between the diffusion-weighted phase image and the phase image without any diffusion-weighting; and (h) computing the intravoxel diffusion gradient along the direction of the diffusion-encoding gradient pulses from the phase difference with a display of images of the measured intravoxel molecule diffusion gradient in the MRI system.