Research

Overview

Dr. Lee’s specific research interests include the development of novel magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) techniques to assess the integrity of structural, functional, physiological aspects of the brain in vivo at the cellular and molecular level. The research goals of his lab are 1) to identify the underlying mechanisms of improved brain health and cognitive performance associated with behavioral interventions and/or new targeted therapies in aging population, 2) to understand key pathologic mechanisms underlying disease activity, clinical status and disease progression in neurological disorders including Alzheimer disease and multiple sclerosis in the living brain, 3) to guide the development of new targeted therapies and intervention strategies, and 4) to offer novel possibilities for directly monitoring the impact of new treatment options and lifestyle choice (e.g., exercise and diet) through quantitative, non-invasive neuroimaging indices of brain health in aging, Alzheimer disease (AD), AD-related diseases and other neurodegenerative diseases. An example of his research topics is listed below.

Assessing microstructural changes in the brain of patients with multiple sclerosis:
Multiple sclerosis has been known as a white matter disease in the human brain. However, increasing evidence suggests the presence of gray matter pathology, which has been suggested to be closely associated with disease status and cognitive deficits. A new generation of MRI techniques allow us to explore new possibilities to visualize such pathology in living humans. A new emerging MRI technique, diffusional kurtosis imaging (DKI), can characterize microstructural organization at the cellular level through evaluation of both Gaussian and non-Gaussian properties of water diffusion. We studied over 50 patients with multiple sclerosis to measure subtle microstructural changes among major subtypes of the disease at 3 T using DKI technique, and investigate association between DKI parameters and cognitive function such as memory and executive function and processing speed. Our data showed that diffusion parameters were sensitive to distinguish the microstructural differences among the subtypes of multiple sclerosis and these parameters were correlated with the disease duration and the clinical disease severity scale of multiple sclerosis, Expanded Disability Status Scale (EDSS), as well as information processing speed and executive planning. We found that various diffusion parameters could indicate different pathologic features of multiple sclerosis in a region-specific manner and show promise in serving as sensitive biomarkers of the pathophysiology.