Characterization of white matter degeneration in elderly subjects by magnetic resonance diffusion and FLAIR imaging correlation

• Published in: NeuroImage (Orlando, Fla.) Vol. 47; pp. T58 - T65
• Main Authors: Zhan, Wang, Zhang, Yu, Mueller, Susanne G., Lorenzen, Peter, Hadjidemetriou, Stathis, Schuff, Norbert, Weiner, Michael W.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2009; Elsevier Limited
• Subjects: Aged; Aging; Anisotropy; Bipolar disorder; Brain - pathology; Brain damage; Computer Simulation; Correlation analysis; Diffusion; Diffusion Magnetic Resonance Imaging - methods; Diffusion tensor imaging; Female; Fluid attenuated inversion recovery; Humans; Magnetic Resonance Imaging - methods; Male; Myelin Sheath - pathology; Neurodegenerative Diseases - pathology; Organ Size; Schizophrenia; Studies; White matter degeneration; White matter lesion; White matter degeneration; Correlation analysis; Fluid attenuated inversion recovery; Diffusion tensor imaging; White matter lesion
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2009.02.004

Fluid attenuated inversion recovery (FLAIR) and diffusion tensor imaging (DTI) techniques have been widely used to evaluate white matter (WM) alterations associated with aging, dementia and cerebral vascular disease. The relationship between FLAIR detected WM lesions (WML) and DTI detected WM integrity changes, however, remains unclear. To investigate this association, voxelwise correlations between 4 Tesla DTI and FLAIR images from elderly subjects were performed by relating WML volume and intensity in FLAIR to fractional anisotropy (FA) and mean diffusivity (MD) in DTI. Significant DTI–FLAIR correlations were found in regions overlapping with the WML of moderate intensities in FLAIR. No significant correlations were detected in periventricular regions where the FLAIR intensities are particularly high. The findings are consistent with a transitional model for WM degeneration from normal WM to cerebrospinal fluid (CSF). The results show that the correlation between DTI and FLAIR disappears when the FLAIR intensity of WML reaches its maximum at a certain lesion severity, and that the correlations may remerge with reversed signs when the lesion severity is further increased. These results suggest that the different stages of WM degeneration in elderly subjects can be better characterized by regional DTI–FLAIR correlations than single modality alone.