The Ocular Surface Institute, or TOSI (pronounced as “To See“), is the leading ocular surface institute in the United States, with the goal of broadening translational research in ocular surface health. Over the years, the University of Houston, College of Optometry (UHCO) has shown a dedicated commitment to the pursuit of research across multiple aspects of vision science. In 2012, the opening of the Vision Institute located at the University of Houston Health & Biomedical Sciences Building, has provided the opportunity to advance ocular research with state of the art technology in a modern setting that is designed to facilitate collaborations across multiple disciplines. It is TOSI‘s goal to develop the world‘s broadest and most visionary research institute devoted to ocular surface translational research.

Read Our Dean's Words

Primary Contacts

Administrative Head

Alison M. McDermott PhD

Ocular Surface Biology Leads

Alison M. McDermott PhD
Rachel Redfern OD, PhD

Clinical Science Leads

Eric Ritchey OD, PhD
Dan Powell OD, PhD
David Berntsen OD, PhD
James Wolffsohn BSc(Hons), PhD

Visual Optics and Imaging Leads

Jason Marsack PhD
David Berntsen OD, PhD
Dan Powell OD PhD

Discovery and Development Leads

Alison M. McDermott PhD
Eric Ritchey OD, PhD
James Wolffson BSc (Hons) PhD

Faculty Affiliates

David Berntsen, O.D., Ph.D., FAAO

Associate Professor, UHCO

Dr. David Berntsen‘s research interests include juvenile-onset myopia, contact lenses, and both central and peripheral aberrations of the eye. He completed a Cornea and Contact Lens Advanced Practice Fellowship in 2004 at The Ohio State University where he examined the effects of overnight orthokeratology on higher-order aberrations, visual acuity, and refractive error-specific quality of life. He completed a PhD in Vision Science in 2009 at The Ohio State University where he conducted a randomized clinical trial evaluating current theories of myopia progression in children. His PhD training included a strong background in epidemiology and clinical trials methodology. Dr. Berntsen has been involved in multiple other adult and pediatric studies in the areas of contact lenses, dry eye, and higher-order aberrations of the eye.

Alan R. Burns, Ph.D.

Professor, UHCO

Dr. Alan Burns is a Professor with 40 years experience in cell biology and microscopic imaging. During the past seven years, his research program has centered on the cornea. The location of the cornea makes it vulnerable to traumatic injury, either accidental or as a result of surgery. Healing of corneal wounds is of vital importance, not only to ensure the integrity of the eye but also to maintain the best possible visual acuity. The mechanisms regulating healing after corneal injury are not fully understood. Migration of inflammatory cells to the site of corneal injury appears to be beneficial for wound healing. Inhibition of inflammatory cell migration results in impaired wound healing, and decreased growth of specific cells in the cornea (keratocytes, nerves and epithelial cells). His experiments are designed to understand the mechanisms regulating inflammation and wound healing within the injured cornea.

Chengzhi Cai, PhD

Professor, UH Department of Chemistry

Dr. Chengzhi Cai is a Professor at the University of Houston‘s Department of Chemistry. He serves as the Director for Mass Spectrometry Laboratory and the Co-Directer for Chemical Biology Interdisciplinary Program at UH. He completed his PhD in Chemistry at the Swiss Federal Institute of Technology (ETH-Zurich) in 1996, followed by postdoctoral training at the Institute of Quantum Electronics, also at ETH-Zurich. His research involves organic synthesis, antimicrobial peptides, bacterial biofilms, organic thin films, surface functionalization and nanochemistry. In addition to the fundamental studies, he also work with collaborators to solve significant biological and biomedical problems of interest, particularly related to ocular surface diseases and novel approaches to characterizing, altering or developing contact lens polymers, and prevention of pathogenic biofilm formation.

Vivien Coulson-Thomas, PhD

Assistant Professor, UHCO


My research involves primarily the study of glycosaminoglycans and proteoglycans in the fields of cornea, cancer, wound healing, stem cells, inflammation, development, spinal cord injury and nerve regeneration. This unique interdisciplinary approach aims to decipher the role of glycosaminoglycans in development and pathology. One of our ongoing projects is to unveil the role of hyaluronan (HA) in ocular surface development and pathology using knockout approaches. We have previously shown that umbilical cord mesenchymal stem cells synthesize a rich extracellular HA modified glycocalyx that regulates inflammatory cells enabling these cells to survive xenograft rejection. We are currently developing umbilical cord mesenchymal stem cells and their hyaluronan rich glycocalyx for treating inflammatory disorders. Recently, we demonstrated that tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6), an HA binding protein, is expressed in the CNS and is rapidly up-regulated after injury, and is present within the glial scar, potentially coordinating and stabilizing the formation of this HA-rich matrix. We are currently investigating the function of TSG-6 in the glial scar and the therapeutic potential of targeting TSG-6 after CNS injury.

Samuel Hanlon, O.D., PhD, M.S., FAAO

Research Associate Professor, UHCO

Since graduating from the Southern California College of Optometry (SCCO) in 1977, Dr. Hanlon has earned a master of science in higher education degree and a PhD in physiological optics. From 1999 to 2012 he served as a full-time clinical associate professor at the University of Houston, College of Optometry (UHCO) teaching clinical procedures laboratories and serving as a clinical attending in family practice. Prior to his appointment at UHCO, Dr. Hanlon was in private practice in the state of Washington four years, an instructor at SCCO for six years, chief of the eye clinic at an HMO on Guam for nine years, assistant professor and department chair at Southern College of Optometry for three years. After receiving his PhD in May of 2012, he has worked as a research associated professor at UHCO. His research includes in vivo and histological animal studies related to corneal inflammation and wound healing, as well as meibomian gland dysfunction and contact lens-related inflammatory events.

Alison McDermott Ph.D.

Scientific Director, The Ocular Surface Institute
Golden-Golden Professor, UHCO

Dr. Alison McDermott is the Scientific Director of TOSI. Dr. McDermott received her Bachelor of Science degree in biochemistry from the University of Surrey, in Guildford, UK and her PhD, also in biochemistry, from Imperial College of Science, Technology and Medicine, London, UK. She then joined the lab of Dr. Geoffrey Sharp at Cornell University in Ithaca in upstate New York. After three years at Cornell studying intracellular signaling pathways she then moved a little west to work with Dr. Richard Haslam at McMaster University in Hamilton, Ontario. Here she further pursued her interest in signaling proteins. The next move was further west, to the campus of the University of Wisconsin, Madison. Here she joined the lab of veterinary ophthalmologist Dr. Christopher Murphy and so began her career in eye research. The most recent move (although this was back in 1998) brought her south to the University of Houston where she has an active federally funded research lab and teaches various courses to both professional students of optometry and graduate students.
The primary goal of her research program is to gain a better understanding of the ocular surface epithelia at the cellular and molecular level which will lead to treatment strategies for ocular surface inflammatory, infectious disease and wound healing following injury and refractive surgery. The major focus of her research is to investigate the functions of antimicrobial peptides such as defensins and cathelicidin at the ocular surface, in addition to the role of inflammation in the pathogenesis of dry eye and characteristics of corneal keratocytes and their repair phenotypes. Her NIH funded research employs cell and molecular techniques and murine models to investigate both the direct antimicrobial and immunomodulatory properties of antimicrobial peptides at the ocular surface.

Jason Marsack, PhD

Assistant Professor, UHCO

Dr. Jason Marsack received a BS in Computer Engineering from Texas A&M University, a MS in Biomedical Engineering from The University of Texas, and a PhD in Physiological Optics and Vision Science from The University of Houston, College of Optometry. His primary research project centers on investigation of optical and visual performance associated with custom corrections for highly aberrated keratoconic eyes. His research interests include characterizing optical aberration of normal and pathological eyes, custom and pseudo-custom correction of optical aberration, visual performance, metrics of optical quality and the use of contact lenses as drug delivery vehicles.

Daniel Powell, OD, PhD

Clinical Assistant Professor, UHCO

Daniel Powell, OD PhD joined the College of Optometry faculty in 2013. In 1995, he received his Doctor of Optometry degree from Pacific University in Forest Grove, Oregon. Dr. Powell practiced in Washington State following completion of a medical-based eye care residency in Reno, Nevada. He relocated to Columbus, Ohio in 2007 to obtain his Master of Science (2011) and Doctor of Philosophy (2013) degrees from The Ohio State University. While at Ohio State, Dr. Powell served as a Clinical Instructor, was awarded the Beta Sigma Kappa Research Fellowship, and was a two-time recipient of the William C. Ezell Fellowship.

Dr. Powell's teaching interests include the areas of human anatomy and physiology. His research investigates the roles that environmental influences may have on ocular surface health, most notably in common conditions like dry eye. He has served as a co-investigator or key personnel on several industry and government-sponsored dry eye and contact lens-based research projects. Dr. Powell also has served as a manuscript reviewer for several prominent vision science-based professional journals.

Guoting Qin, PhD

Research Assistant Professor

Dr. Guoting Qin received her bachelor's degree in Chemistry in 2002 from the University of Science and Technology of China, and her PhD in 2007 from the University of Houston working on surface biofunctionalization, especially with antimicrobial peptides and carbohydrates. She then spent six years at Houston Methodist Research Institute at the Texas Medical Center, where her research focused on nano- /micro- particle-based imaging and drug delivery systems.

Dr. Qin's current research interests are to apply biomaterials, nanotechnology, and chemistry to address problems related to the ocular surface, such as infection, meibomian gland dysfunction, and contact lens discomfort.

Vijay Raghunathan PhD

Assistant Professor, UHCO


Dr. Raghunathan received his first degree in Biomedical Engineering from Visvesvaraya Technological University, India, and subsequently his M.Sc and Ph.D in Bioengineering from the University of Strathclyde in Glasgow, UK. He then completed a postdoctoral fellowship at the University of Bristol, UK investigating the safety of tribological wear released from orthopaedic implants. He then made his foray into vision science by completing a postdoctoral fellowship at the University of California Davis, jointly in Drs. Chris Murphy and Paul Russell’s laboratories, investigating the principles underlying the mechanobiology of the trabecular meshwork and cornea. He has recently joined the faculty at the College of Optometry at Houston and brings a diverse skill set in cell & molecular biology, biomaterials, and biomechanics. The primary goals of his research program are: (a) to understand the role that extracellular matrix play in ocular diseases, (b) to develop and utilize engineering tools in studying biomechanics and surface phenomena at the ocular surface interface, and (c) to use materials based strategies for development of therapeutics.

Rachel Redfern, O.D., Ph.D.

Assistant Professor, UHCO

Dr. Rachel Redfern received her bachelor's degree in biology from Texas A&M University. She then earned her Doctor of Optometry and Ph.D. from the University of Houston, College of Optometry (UHCO) in 2005 and 2010 respectively. Dr. Redfern is a recipient of the Institutional Ruth Kirschstein National Research Post-doctorate Award and the ARVO/Alcon Early Career Clinician-Scientist Research Award. She was previously funded by National Institute of Health and her research investigates the role of toll-like receptors in the pathogenesis of dry eye syndrome and their involvement in modulating the risk for infection when the ocular surface is compromised from dry eye.

Dr. Redfern enjoys interacting with optometry and graduate students. She lectures in the General Pathology and Physiology and Molecular Biology to first year optometry students. Dr. Redfern is a member of the Association for Research in Vision and Ophthalmology, the American Academy of Optometry and the Tear Film and Ocular Surface Society. She is also a William C. Ezell Fellow and a reviewer for several journals including Investigative Ophthalmology and Vision Science, Public Library of Science ONE, Cellular and Molecular Life Sciences, and Optometry and Vision Science.

Eric Ritchey, OD, PhD, FAAO

Clinical Assistant Professor, UHCO


Dr. Ritchey is a clinician-scientist who joined the faculty of the College of Optometry in 2015. His research interests are in regulation of ocular growth, contact lenses, corneal disease and ultrasound-mediated gene transfer. He completed an Advanced Practice Fellowship in Cornea and Contact Lenses at The Ohio State University in 2003, where he examined differences in visual performance and quality of life measures between overnight orthokeratology and 30-day extended wear silicone hydrogel contact lenses wearers. In 2011 he completed his PhD in Vision Science at The Ohio State University, where he examined vision-guided ocular growth in a mutant animal model with congenital vision loss. From 2011 to 2015, Dr. Ritchey was a Principal Research Optometrist in the Emerging Technologies group at Johnson & Johnson Vision Care, where he worked on the development and evaluation of novel contact lens designs. Dr. Ritchey’s career has provided him with a strong background in clinical trial design and execution, as well as in basic laboratory science.

In the professional program, Dr. Ritchey teaches Ophthalmic and Contact Lens optics to second year optometry students and serves as an attending in the Contact Lens Service. He is a Fellow of the American Academy of Optometry and a 2-time Ezell Fellowship awardee.

Maria K Walker, O.D., M.S., FAAO

Instructor/Graduate Student

Dr. Maria K. Walker joined the faculty at the University of Houston College of Optometry in the fall of 2014, as an Assistant Clinical Professor. She earned her Doctor of Optometry and Master of Vision Science degrees from the New England College of Optometry in Boston, MA (2013), and went on to complete a Residency in Cornea & Contact Lenses at Pacific University in Forest Grove, OR (2014). She is a Fellow of the American Academy of Optometry, and a member of the Association for Vision in Research and Ophthalmology.

As an Assistant Professor at UHCO, Dr. Walker works as an Attending Clinician to third and fourth year optometry students, and lectures in the introductory and advanced contact lens courses. She is involved in various research initiatives, including the exploration of the tear reservoir beneath scleral contact lenses, the clinical performance of specialty contact lenses, and the effect of contact lenses on corneal and tear film physiology in individuals with corneal disease. She is a co-investigator on the Bifocal Lenses in Nearsighted Kids (BLINK) study, a multi-center project looking at the role of multifocal soft contact lenses in reducing myopia progression in children. Recently, Dr. Walker has begun pursuing a PhD in Physiological Optics at UHCO.

James Wolffsohn, BSc (Hons), PGCertHE, PGDipAdvClinOptom, MBA, PhD, FCOptom, PFHEA, FSB, FAAO (diplomat), FIACLE, FBCLA

Adjunct Professor, UHCO

Following a 1st class Optometry degree from Manchester, a pre-registration year at Moorfield´s Eye Hospital, London, a PhD at Cardiff University and a clinical/research fellowship at the University of Melbourne, Australia, Professor Wolffsohn was appointed by Aston University in 2000, where he was Head of Optometry 2004-9, being awarded a personal Chair in 2007. He is now Deputy Executive Dean for Life and Health Sciences at Aston University as well as being an Adjunct Professor at the University of Houston, College of Optometry.

James has published over 150 peer reviewed academic papers and given numerous international presentations. His main research areas are the development and evaluation of ophthalmic instrumentation, contact lenses, intraocular lenses and the tear film. He is the academic Chair of the British Contact Lens Association, having been a past president and is Chair of the 2nd Dry Eye Workshop Diagnosis Sub-committee.

Graduate Students/ Post-Doctoral Fellows

Alyce Alven, BS

OD/MS Candidate.
Advisor: Rachel Redfern, OD PhD

Alyce Alven is currently pursuing her OD/MS at the University of Houston College of Optometry (UHCO) with plans of pursuing her PhD when she graduates in 2016. She graduated with a Bachelors of Science in Advertising from the University of Houston in 2010 with a focus in media buying and selling. Since beginning research in 2013 with UHCO's summer research program, her primary focus has been on dry eye with Dr. Kelly Nichols and now with Dr. Rachel Redfern investigating the role of damage associated molecular patterns in stimulating dry eye inflammation in patients and ocular surface cells. As president of Student Volunteer Optometric Services to Humanity, she also has participated in vision screenings, the Special Olympics, and has gone abroad to Mexico and Peru.

Carolina M.E. Kunnen, BOptom, B.ApSc (Orthoptics), PhD

Postdoctoral Fellow

Advisor: Dr. Rachel Redfern

Carolina is a Dutch qualified optometrist and orthoptist with over ten years of clinical experience. Carolina completed her PhD at the Brien Holden Vision Institute and University of New South Wales in Sydney, Australia. Carolina’s research fostered a better understanding of the relationship between ocular symptomatology and meibomian gland morphology and function. During her PhD studies, she received several academic and travel awards, including the prestigious Ezell Fellowship in 2012.

Her track record also includes creating a new scientific division at the Netherlands Contact Lens Congress (NCC), nine years of experience setting up and leading a non-government organization that provides eye care in Ghana, Africa (The Optical Foundation), and several years of teaching in the Netherlands, Ghana and Australia.

At the University of Houston, Carolina joined Dr. Redfern’s lab, and is also involved in the clinical trials at The Ocular Surface Institute.

Kelly Moore, BS

OD/MS candidate.
Adviser: David Berntsen, OD, PhD

Kelly Moore is currently pursuing a combined OD/MS degree at the University of Houston College of Optometry. She received her B.S. at Wheaton College, Wheaton, IL in Chemistry. She is conducting research on myopia progression under the direction of Dr. David Berntsen, OD, PhD, FAAO. Since the summer of 2013, she has investigated the off-axis repeatability of an instrument for measuring refractive error, and she is studying how the peripheral defocus profile of myopic eyes is influenced by spherical and multifocal soft contact lenses.

Mylan Nguyen, BS, MSPH

OD/MS Candidate
Advisor: Dr. David A. Berntsen, OD, PhD, FAAO

Mylan Nguyen is currently pursuing a combined OD/MS degree at the University of Houston College of Optometry. She received her BS at the University of Texas at Austin in Human Biology and her MSPH at the University of Texas School of Public Health in Epidemiology. She is conducting research on myopia progression under the direction of Dr. David Berntsen, OD, PhD, FAAO. Since the summer of 2015, she has investigated the between-instrument agreement and repeatability of an instrument for measuring lower-order and higher-order aberrations, and she is identifying metrics that are predictive of retinal image quality in multifocal soft contact lens wearers.

Rose Reins, BA, PhD

Post-Doctoral Fellow
Advisor: Rachel Redfern, OD PhD

Rose Reins received her PhD in Cell and Molecular Biology from the University of Houston and currently holds a joint post-doctoral position with Drs. Alison McDermott and Rachel Redfern. Rose's research interest lies in investigating the function of vitamin D at the ocular surface, with a focus on its role in modulating inflammation. She is examining the effect of topical vitamin D on experimental dry eye, with the aim of finding an anti-inflammatory therapeutic for this common ocular surface disease. Apart from her studies, Rose enjoys food and exercise and her two young daughters keep her happily busy.

Kelsea Vance, BS

OD/MS Candidate.
Advisor: William Miller OD PhD/Jan Bergmanson OD PhD

Kelsea Vance is pursuing a combined OD/MS degree at the University of Houston College of Optometry. She received her Bachelors of Science at the University of Arkansas in Biology. Kelsea began research in 2014 as part of UHCO's Summer Research Program with a focus on scleral contact lenses, working with Dr. William Miller, OD, PhD. She is currently exploring the influence of post-lens tear exchange and other fitting elements in interrupted and uninterrupted scleral contact lens wearers.

Betty Zhang, BS

OD/MS Candidate
Advisor: Rachel Redfern, OD PhD

Betty Zhang is pursuing combined OD/MS degrees at the University of Houston College of Optometry. She received undergraduate degrees in Biology and Psychology from Washington University in St. Louis. Betty currently works under the direction of Dr. Rachel Redfern, O.D., Ph.D. studying the pathogenesis of dry eye syndrome. She is investigating the role of toll-like receptors in the increase of pro-inflammatory molecules in an experimental dry eye mouse model.

Staff Members

Hasna Baidouri, BS

Lab Manager

Ms. Hasna Baidouri received her Bachelor of Science degree from Chouaib Doukkali University, El Jadida Morocco in 1995. After working as a medical technologist for two years she moved to the US and for several years worked as a research specialist studying HIV and cancer at both Lincoln University and University of Pennsylvania, Philadelphia. She has been laboratory manager of the McDermott lab since 2010 working on diverse projects related to antimicrobial peptides, ocular surface infection and inflammation.

Sonia Huerta, A.A.S

Ophthalmic Technician

Mrs. Sonia Annette Huerta graduated from San Jacinto College Central with an Associate's Degree of Applied Science in Eye Care Technology. During this education she developed skills to assist optometrists and ophthalmologists in practice including pre-testing, contact lens fitting, and refraction. She gained experience by interning at Lyndon B. Johnson Hospital, Retina Consultants of Houston, Wooten Vision Care, Northwest Eye Associates, Plastic Eye Surgery Associates, and Safety Rx. She has volunteered for the Essilor's Kid's Vision for Life "See to Succeed" SJC Collaborative Partnership Project. She currently works to assist in administrative duties of TOSI as well as assist the research optometrists during examinations.

Satya Kolar, PhD

Research Associate

Dr. Satya Kolar obtained her M.S. in Nutrition and Biochemistry from University of Kentucky, Lexington, KY and PhD in Biochemistry and Molecular Biology from Texas A&M University, College Station, TX. Satya received her MD from Bangalore University in India where she practiced as a clinician before moving to the U.S. of America.

During her PhD training her research emphasis was on the effect of n-3 PUFAs on colon carcinogenesis. She then joined the McDermott lab as a Post-doctoral Fellow and has been working on projects related to infection and immunity at the ocular surface. In addition, she has worked on projects exploring methods to enhance efficacy of antimicrobial peptides via liposomal delivery in collaboration with the Chemistry department. Her work also includes projects related to studying the efficacy of contact lens solutions against Acanthamoeba. Satya's current research focuses on investigating the role of antimicrobial peptides in bacterial and fungal keratitis.

Carolina Lema, Ph.D.

Researcher, TOSI

Dr. Carolina Lema earned her BS degree in Biochemistry from Universidad Mayor de San Andres, La Paz-Bolivia in 1994 and her PhD degree in Immunogenetics from Kagoshima University, Kagoshima-Japan in 2002. Her postdoctoral training was focused on cancer genomics and Toxicogenomics at the Houston Advanced Research Center, The Woodlands, TX. She previously worked as staff scientist at the Cell Culture and High-Throughput Screening Core Facility at the University of Texas at El Paso for five years. In February 2013, she joined Dr. Redfern‘s lab at The Ocular Surface Institute to investigate the pathogenesis of dry eye inflammation and the risk for infection in the desiccated ocular surface.