Guest: Dr. Joyce Liao; Eye-brain issues in microgravity, vision issues in space, eye medical instrumentation in space, optic nerve and fluid pressure plus more.
Dr. Liao is a clinician-scientist who is dedicated to making basic discoveries and improving clinical care and treatment of patients with neuro-ophthalmic conditions (issues that affect vision due to nervous system issues). Dr. Liao received her undergraduate degree with high honors from Harvard University in Biochemical Sciences and her M.D., Ph.D. in Neuroscience (Medical Scientist Training Program) and Fellowship in Neuro-Ophthalmology from University of California San Francisco. She serves as the Director of the Neuro-Ophthalmology Service and Neuro-Ophthalmology Fellowship as well as Co-Director of the Vision Research Training Program.
A major area of research is the understanding and treatment of human conditions that lead to retinal ganglion cell loss and irreversible thinning of the optic nerve, the only connection between the eye and the brain. This includes hypoxic-ischemic, autoimmune, and other causes. Hypoxic (loss of oxygen), ischemic (loss of blood flow) injury is common in all age groups and can occur as a result of perinatal asphyxiation in babies; near-drowning and poisoning in children; or cardiac arrest, stroke, pulmonary diseases, peri-operative complications, high altitude exposure, and space travel in adults. Dr. Liao uses animal model of HYPOXIA to study what happens to the optic nerve, retina, and brain in lower oxygen. In high altitude, some patients with selective vulnerability can develop ischemic optic neuropathy, which leads to irreversible vision loss. In prolonged space travel, the majority of astronauts develop optic nerve edema and retinal changes, which are of unclear mechanism but may be due to a combination of microgravity, hypoxic-ischemic injury, and other causes. Dr. Liao's group is also studying ANTERIOR ISCHEMIC OPTIC NEUROPATHY, the most common acute optic neuropathy in adults. Current research areas for optic neuropathies include: 1) Development of state-of-the-art in vivo optical, magnetic resonance imaging, and positron-emission tomography techniques in the eye and brain in humans and animal models of hypoxic-ischemic injury, in order to identify novel biomarkers that can help direct treatment; 2) Study of the cellular and subcellular changes to the retinal neurons, glia, axons and axonal transport following optic nerve injury; and 3) Development of highly promising treatment approaches for optic neuropathies and vision loss, including neuroprotection and regenerative therapy, in order to identify effective ways to treat human vision loss in the future.
A second major area of research is on clinical assessments of visual function and vision rehabilitation. Visual disability is significantly greater in almost all patients with neuro-ophthalmic conditions, because they impact daily activities such as driving, using a computer, and work. Dr. Liao founded the Stanford Human Ocular Motor Lab in 2006 and has 3 video infrared eye trackers that have been systematically used to measure eye behavior in hundreds of subjects with a variety of vision and eye movement issues. Her research focuses on how important visual function, such as reading and watching scenery (e.g. on TV), is affected by eye and brain diseases. The goal is that one day, she can use eye behavior to understand how different neuro-ophthalmic diseases impact visual function and to design better rehabilitation to help patients improve their visual function and quality of life. By recording and studying eye behavior during functional visual tasks like reading and watching a movie, which requires a combination of good vision and eye movement control, Dr. Liao hopes to decipher what contributes to visual dysfunction in the real world and design appropriate treatment and rehabilitation in the future.