Evaluating intensity standardization and inhomogeneity correction in magnetic resonance images

Image intensity standardization is a recently developed postprocessing method designed for correcting acquisition-to-acquisition signal intensity variations inherent in MR images. Inhomogeneity correction is a method used to remove the low spatial frequency background non-uniformities that exist in MR images. Both these procedures have important implications for MR medical image segmentation, registration and image analysis. The effects of these post-processing operations on improvement of image quality in isolation has been well documented. However, the combined effects of these two processes on MR images has not been studied thus far. In this paper, we evaluate the effect of inhomogeneity correction followed by standardization on MR images and vice-versa, in order to determine the best sequence to follow for enhancing image quality. We found that improved standardization was achieved by preceding it with correction, and image inhomogeneity was greatly reduced by standardizing and then correcting