Image-based MRI Gradient Estimation

In order to reduce geometric distortion phenomena in MR images, every MRI system main magnet undergoes a shimming process. Since this process aims at optimizing magnetic field homogeneity within a so-called uniformity sphere, image quality outside this sphere is neglected.Since the fields vary smoothly in space, MR signal-to-noise ratio is still non-zero just outside the uniformity region, but correction of MR image distortion fails due to lack of magnetic field knowledge outside it.We propose a novel algorithm for measuring all the fields involved in the generation of images.

Source: Magnetic Resonance Imaging - January 2, 2018 Category: Radiology Authors: R. Acquaviva, S. Mangione, G. Garbo Source Type: research