MR Elastography of Cognitive Impairment

Due to shifting demographics, the prevalence of dementia continues to increase in the population. To mitigate the effects of dementia will require new treatments working jointly with new methods for earlier and more sensitive diagnosis of the diseases. Magnetic resonance elastography (MRE) is a noninvasive technique for measuring tissue stiffness. MRE is a three-step process beginning with the introduction of shear waves into the tissue of interest with an external vibration source. The shear waves are imaged with a phase-contrast MRI pulse sequence and the resulting wave images are mathematically inverted to calculate tissue stiffness. Preliminary data indicate that global brain stiffness is highly reproducible and that Alzheimer's disease causes a decrease in brain stiffness when compared to age- and gender-matched cognitively normal controls. The purpose of the proposed work is to further investigate the potential of brain stiffness as a novel biomarker for Alzheimer's disease. A comparison between brain stiffness and existing Alzheimer's disease biomarkers will help determine the biological basis of the observed stiffness change and in time may improve the sensitivity of Alzheimer's disease diagnosis and grading.