This study hopes to investigate differences in lymphatic health of patients with Alzheimer's
disease by analyzing diffusion-weight images in conscious and sleep states. Dexmedetomidine
is a short-acting agent that facilitates a sedated state characterized by slow waves and
inhibition of norepinephrine. Conceptually, dexmedetomidine may be preferred to other agents,
because it is a short-acting norepinephrine blocker, which could mimic slow wave sleep
architecture, opening interstitial spaces, and facilitating plaque removal. Dexmedetomidine
may also be preferred given its safety profile among the elderly and acutely ill compared to
other anesthetic agents. Sleep will be induced with dexmedetomidine, and interstitial fluid
convection will be assessed by measuring free-water diffusion imaging. Freewater diffusion
imaging separates out the contributions of extracellular free water and water in the vicinity
of cellular tissue; it is used to evaluate abnormalities in extracellular space, such as
neuroinflammation, which may contribute to long-term cellular degeneration. This method of
analysis could be useful in assessing the lymph systems ability to remove extracellular
debris.