Current Research and Scholarly Interests
Major Ophthalmology, Radiology, Neuroscience, and Biomedical Engineering-related Research Directions:
(1) Glaucoma Neuroimaging and Neurotherapeutics in Humans and Experimental Animal Models:
Glaucoma is the leading cause of irreversible blindness in the world. Although elevated eye pressure is a major risk factor, recent evidence suggests the involvement of the brain’s visual system, apart from the eye, in the early degenerative mechanisms of the disease. However, the pathogenesis of glaucoma in the visual system remains largely undetermined. Our lab's research goal is to develop and apply novel and useful imaging techniques for whole-brain, non-invasive, and longitudinal measurements of damage and disease progression in glaucoma patients. Our recent research has demonstrated structural, metabolic, and functional relationships between eye, brain, and vision loss in patients across disease stages when brain MRI findings are compared with clinical ophthalmic assessments. We also combine ocular imaging, neuroimaging and neurotherapeutic approaches to guide vision preservation and restoration in humans and experimental animal models of acute/chronic intraocular pressure elevation, genetic mutations/knockouts, central insulin resistance, and glymphatic dysfunction with relevance to glaucoma. The characterization and monitoring of glaucoma in both the eye and brain can lead to more timely intervention and targeted treatments to reduce the prevalence of this irreversible but preventable neurodegenerative disease.
(2) The Neural Basis of Sensory Substitution in the Blind:
Vision loss is a major health problem worldwide. Although sensory substitution devices can assist patients to 'see' with their remaining sensory modalities by converting live visual information into patterns of sound or touch, little is known about how these new, alternative sensory patterns interact with the brain to influence perception and behavior in the blind. Our lab aims to investigate sensory substitution technologies and improve visual neurorehabilitation strategies, by identifying the structural, metabolic, and functional brain circuits involved in sensory substitution, and by examining the plastic brain changes resulting from multisensory training through the combined use of advanced neuroimaging and neuromodulation techniques as well as artificial intelligence.
(3) Ocular Structures and Physiology:
To date, the regulatory mechanisms of ocular fluid circulation and their contributions to the pathogenesis of ocular hypertension and glaucoma remain unclear. Our lab studies the aqueous humor dynamics, retinal pathophysiology, and microstructures and macromolecules in the sclera and cornea to understand the basics of ocular biomechanics and guide controlled ocular drug delivery. We also study the efficacy of novel ocular reconstruction approaches such as whole-eye transplantation, osteo-odonto-keratoprosthesis, and cataract surgery for vision restoration.
(4) Imaging Methods Development for Examining the Visual System:
Understanding the mechanisms of vision in health and disease requires knowledge of the anatomy and physiology of the eye and the neural pathways relevant to visual perception. As such, developing imaging techniques for the visual system is crucial for unveiling the neural basis of visual function or impairment. In our laboratory, we develop and refine advanced MR imaging and spectroscopic methods to improve the sensitivity and specificity for evaluating the visual system in health and disease. These techniques include contrast-enhanced MRI (using manganese, gadolinium, iron oxide nanoparticles, and chromium, for example), diffusion MRI, task-based and task-free functional MRI, optogenetic fMRI, cerebrovascular reactivity, magnetic resonance spectroscopy, susceptibility-weighted MRI, and magic angle–enhanced MRI of the eye and the brain.
