Research
RESEARCH
Our Technology
Dr. Yuqiang Bai, with degrees in physics, optics, and biomedical engineering, has spent his recent career doing what science so far has failed to do. He has developed imaging systems that are able to analyze and measure the thickness of the eye's tear film directly. His newest iteration, which utilized the principles of thin film interferometry, has unprecedented resolution and a field of view larger than any similar imaging system. With the associated data processing algorithm Dr. Bai has designed, our lab is able to determine tear film thickness pixel by pixel on a novel scale. With this technology, we hope to build on the body of research working to unravel the causative mechanisms behind the unstable tear films that lead to dry eye disease.
Clinical Research
Currently supported by both an R01 grant and an R21 grant from the National Eye Institute, our primary research area is dry eye disease (DED). We are correlating the microstructural thickness variations of the tear film lipid layer with clinical characteristics of the ocular surface in healthy patients and in those with DED.
Unprecedented Resolution & Analysis
Previous work from our group suggests that destabilization and evaporation of the tear film are dependent on the physical distribution of the fluid across the corneal surface as well as overall thickness. We are taking this work a step further to analyze tear film dynamics. Our imaging system can assess changes in the tear film between blinks on a nanoscale level. This previously unavailable resolution can give us more insight into microscopic changes on the ocular surface like never before.
Collaborations
The Bai lab, always open to collaboration, is currently working with ophthalmologists in the University of South Florida's Eye Institute to analyze tear film dynamics in two clinically relevant conditions.
Thyroid eye disease (TED) or Graves' ophthalmopathy is most common in people experiencing an overactive thyroid gland (hyperthyroidism). It appears visually as bulging eyes (proptosis) caused by the immune system attacking the muscles and tissues around the eyes, leading to swelling behind the eye sockets. Symptoms of DED are common in patients with TED, as the bulging of the eyes and eyelid retraction often prevents the eyes from closing completely. We are working with clinicians within the USF Health Eye Institute who see patients with TED to correlate tear film microstructural thickness variations with clinically measured parameters of DED.
Blepharoplasty is a minor surgical procedure to remove excess skin or fat from the eyelid for functional or aesthetic reasons. Patients undergoing upper blepharoplasty can experience short term dry eye symptoms caused by swelling after surgery interfering with the function of the lacrimal glands. Patients also risk experiencing new or worsened permanent dry eye following surgery, especially if too much skin is removed. We are working with clinicians within the USF Health Eye Institute who perform upper blepharoplasties on patients to correlate tear film microstructural thickness variations with clinically measured parameters of DED before and for months following surgery.
Preclinical Research
Animal models are critical in the discoveries researchers of human conditions make daily. DED is no exception. Several animal models of DED have been developed, primarily using New Zealand white rabbits, which feature large globes and similar ocular surface biochemistry to that of humans. By performing manipulations to induce measurable signs of DED in these rabbits, we produce a means to study a human-centric disease without the use of human cells, tissues, or whole organisms.
Our main preclinical research project focuses on producing a dry eye phenotype measurable through changes in ocular surface parameters by various interventions, such as surgery, and systemic and topical drug administration. After inducing DED signs in our models, we will use an adaptation of our primary imaging system specifically suited for rabbits to measure the thickness and dynamics of the tear film. We are especially interested in comparing models of aqueous deficient and evaporative DED produced by inducing meibomian gland dysfunction (MGD).
Our secondary area of preclinical research draws on Dr. Bai's background in physics and optics that he has already utilized to build our current tear film imaging system. We are building a meibography system designed specifically for rabbits. Meibography systems use infrared cameras to image the meibomian glands in patients who may be experiencing MGD and resulting evaporative DED. Though some of these systems have been applied to animal models of DED, they are not well-suited to adapt to the ocular surface and adnexa of species other than human. Our lab is developing a novel meibography system featuring a highly sensitive infrared camera and high magnification objectives in combination with basic engineering components that is designed specifically for use in rabbit models. We will use technology to track meibomian gland dropout and morphology changes throughout the progression of MGD to evaporative DED in these models, as well as compare phenotype progression between models.
Research Support
Dr. Bai has been the Principal Investigator on a number of National Institutes of Health grants, including R21s and R01s. His grants, awarded from the National Eye Institute, span the course of his time as a Postdoctoral Fellow and an Assistant Professor.