| Subcortical hyperintensities (SH) are believed to be observable signs of cerebrovascular disease, indicating some form of subcortical vasculopathy. Also commonly referred to as leukoariosis, these hyperintense signals on proton density, T2-weighted and fluid attenuated inversion recovery magnetic resonance images, are commonly observed phenomena in Alzheimer's disease patients and elderly persons. Several SH sub-types with differential brain-behavior associations have been proposed in the scientific literature: periventricular, deep white, cystic fluid filled lacunar-like infarcts and perivascular Virchow-Robin spaces. This study will present Lesion Explorer (LE): a comprehensive tri-feature MRI-based processing pipeline that effectively and reliably quantifies SH sub-types in the context of additional brain tissues volumetrics in a regionalized manner. The LE pipeline was validated using a scan-rescan procedure. Finally, the LE pipeline was applied in a cross-sectional study of Alzheimer's disease patients and normal elderly controls. Brain-behavior relationships were demonstrated with regional SH volumes and executive functioning, speed of mental processing, and verbal memory. |
