Amanda Ng1,2, Zhaolin Chen2,3, Jingxin Zhang1, Gary F. Egan2,4, Leigh A. Johnston2,5
1Department of Electrical and Computer Systems Engineering, Monash University, Melbourne, Australia; 2Howard Florey Institute, Florey Neuroscience Institutes, Melbourne, Australia; 3Department of Electrical and Electronic Engineering, University of Melbourne, Melbourne, Australia; 4Centre for Neuroscience, University of Melbourne, Melbourne, Australia; 5Department of Electrical and Electronic Engineering & NICTA Victorian Research Laboratory, University of Melbourne, Melbourne, Australia
Phase images in MRI are subject to inhomogeneities at the cortical surface due to susceptibility artefacts induced by air/tissue interfaces and insufficient filtering at foreground/background borders. We present a computationally efficient method of removing these inhomogeneities from phase unwrapped images using spatially dependent filters and omission of background voxels from the filtering calculations. The method is shown to successfully reveal structural detail in the cortical surface that is otherwise obscured in traditional filtering methods.