Contrast enhancement by combining T1- and T2-weighted structural brain MR Images

Masaya Misaki, Jonathan Savitz, Vadim Zotev, Raquel Phillips, Han Yuan, Kymberly D. Young, Wayne C. Drevets, Jerzy Bodurka
2014 Magnetic Resonance in Medicine  
Purpose-In order to more precisely differentiate cerebral structures in neuroimaging studies, a novel technique for enhancing the tissue contrast based on a combination of T1-weighetd (T1w) and T2-weighed (T2w) magnetic resonance imaging (MRI) images was developed. Methods-The combined image (CI) was calculated as CI = (T1w−sT2w)/(T1w+sT2w), where sT2w is the scaled T2-weighted image. The scaling factor was calculated to adjust the gray matter voxel intensities in the T2w image so that their
more » ... ian value equaled that of the gray matter voxel intensities in the T1w image. The image intensity homogeneity within a tissue and the discriminability between tissues in the CI versus the separate T1w and T2w images were evaluated using the segmentation by FSL and FreeSurfer software. Results-The combined image significantly improved homogeneity in the white and gray matter compared to the T1w images alone. The discriminability between white and gray matter also improved significantly by applying the CI approach. Significant enhancements to the homogeneity and discriminability also were achieved in most subcortical nuclei tested, with the exception of the amygdala and the thalamus. Conclusion- The tissue discriminability enhancement offered by the CI potentially enables more accurate neuromorphometric analyses of brain structures.
doi:10.1002/mrm.25560 pmid:25533337 pmcid:PMC4476954 fatcat:xjzzt2kzyzhfrllbl4ktofsg7u