Donald R. Korb, OD

Personal Profile Donald R. Korb, OD An internationally recognized expert in the tear film, Donald R. Korb, OD, is often described as one of the field’s great clinician-scientists. His accomplishments include the development of the first thin membrane hydrogel lens, the forerunner of contemporary soft lenses. He was also the first to describe a number of significant clinical entities, including giant papillary conjunctivitis, meibomian gland obstruction, and lid wiper epitheliopathy. He has founded several research and development companies, including Ocular Research of Boston, which developed Soothe®XP, a lipidbased treatment for dry eye. Dr. Korb takes special pride in having been a Regent’s Lecturer at the University of California, Berkeley.

THE OCULAR SURFACE What drew you to become a clinician-scientist? DONALD R. KORB I was myopic as a child, and my own myopic condition has always interested me. Initially, this inspired me to consider becoming a medical doctor. Then, during my premedical studies, I discovered that I simply didn’t like the sight of blood. I decided against medical school, and the next thing I knew I was studying optometry. I was fortunate to do some very exciting work in the 1960s, when the question at the time was whether one could accurately measure the eye. Working for the Polaroid Corporation here in Boston, I developed two projects: one on profile photography with 60-second infrared film, and the other on corneal topography. In retrospect, it’s clear that our early reconstruction of corneal shape was quite similar to the methods of corneal mapping used today. In the early 1960s, however, ©2008 Ethis Communications, Inc. All rights reserved.

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we lacked the computing power to bring the work to commercial fruition. But it did lay the foundation for later research. My experience with Polaroid was tremendously inspiring and I learned how to invent, to patent, and to collaborate. At the same time, I was practicing—seeing patients 4 or 5 days a week—and doing research using the patient base while spending evenings in the laboratory. My whole research career is built on the appreciation that, when I go into the examining room, I have a golden opportunity to observe what I don’t yet understand. TOS How did you become interested in the interaction of the lid, cornea, and tear film? KORB As I was fitting patients with the original PMMA rigid contact lenses, it became clear to me that the lenses that provided the best clinical results rode high on the cornea, not at the center where the authorities of the time said they should be. So while others were working hard to achieve lenses that fit dead center on the eye, I observed that patients were most comfortable when the lens rode high. The research aspect of me decided to analyze this observation. What I discovered was that a lens that rode high would literally attach to the upper lid. This observation led to a lens design and the technique of lid attachment fitting. Others in the field subsequently named this the Korb technique. This development then led directly to my interest in tear film and the lid, because I came to understand what happened when the lens didn’t attach to the upper lid. When that happens, the lid has to hurdle the lens every time the patient blinks. Blinking is inhib-

ited, with the sequelae of the lid not wiping the ocular surface, and the tear film becomes compromised and dryness occurs. TOS What led to your understanding of giant papillary conjunctivitis (GPC) and who else was pivotal in this work? KORB I’ve had the privilege of working with many gifted researchers, among them the distinguished ophthalmologist and immunologist Mathea Allansmith. Of the numerous studies and publications we worked on together, the best known is our 1977 paper “Giant Papillary Conjunctivitis in Contact Lens Wearers,” which named GPC, established that it occurred with all contact lenses, and explained its cause.1 Like much of my research, this investigation grew out of my clinical work and the challenge of studying symptoms that lacked explanation. Specifically, when I first began fitting extended-wear contact lenses, I saw that some patients developed symptoms of irritation. It’s an old axiom of ophthalmology that an examination isn’t complete until the lids have been everted and massaged. Despite that, almost no clinicians were turning the upper lid to examine the inner lid surface either prior to or in the presence of symptoms with contact lens wearing. When I did so, I found certain lid characteristics and recognized them as a syndrome. At the same time, Dr. Allansmith, who was chief of immunology at what is now the Schepens Eye Research Institute in Boston, made this clinical phenomenon the subject of sophisticated pathological, cytological, and histological investigations.

THE OCULAR SURFACE / JANUARY 2008, VOL. 6, NO. 1 / www.theocularsurface.com

PERSONAL PROFILE / Donald R. Korb, OD

Today, GPC is familiar to every resident in ophthalmology and optometry. And it always will exist because we’ll have GPC or a variant as long as we put objects on the eye, perform surgery on the eye, or otherwise produce irregularities on the eye’s surface. To this day, I continue to work with Dr. Jack Greiner, an ophthalmolgist who was then a PhD anatomist member of the GPC team. TOS How did you develop your understanding of lid wiper epitheliopathy? KORB For years patients were telling us, “My eyes feel scratchy” or “It hurts every time I blink,” but our exam procedures revealed nothing. It might have been tempting to dismiss those complaints as imaginary. The golden opportunity lay in realizing that what we lacked was a test able to elucidate the problem. Intuition told me that the problem area must involve the part of the upper lid that’s in contact with the eye. Further, if that was true, it seemed to me that the underlying problem would be one of inadequate lubrication. What I did then was employ the sequential staining methods Dr. John Herman and I had developed in the 1970s. We knew from this prior work that there are ocular surface phenomena that don’t become evident with one drop of vital stain. But if you keep applying both fluorescein and either rose bengal or lissamine green to the ocular surfaces, the epithelial cells demonstrate staining. The trick was to instill one or both stains onto the eye and wait at least 5 minutes before everting the lid. Then, remarkably, a wide damaged area—which stained—was apparent. We chose to name the area the lid wiper and the pathology lid wiper epitheliopathy. Certainly people before us had everted upper lids and seen pathology on the inner surfaces, as in lid imbrication by Donnenfeld. What we did was make the connection between the staining and the area’s function and the lack of lubrication.

Intriguingly, if you look back in the scientific literature, you see that in 1902, Parsons identified a particular area on the inner surface of the upper lid as making contact with the cornea and bulbar conjunctiva. But between 1902 and when we published in 2005, no one had realized that the lid wiper could be compromised and evidence epitheliopathy. And just like a car windshield wiper blade, the lid wiper of the upper lid becomes ragged when there is inadequate lubrication. TOS What do you consider the most important work of your career? KORB One of the major achievements of my career was the first membrane lens. We developed the CSI membrane lens in 1972 at Corneal Sciences, Inc. That was the company that Miguel Refojo and I founded in 1971 and was sold to Syntex in 1978. The lens came on the market in 1980, and it’s still being used. The polymer we originally employed has since been superseded by newer polymers, but the lens design continues to be used. That is very gratifying to see. A second achievement may ultimately prove to be more important to ophthalmology and optometry. I refer to our work on meibomian gland dysfunction. It traces to a 1980 paper I published with Antonio Henriquez, MD, PhD, who brought to our research his expertise in physiology and pathology as well as in ophthalmology. It would have taken three or four professionals to match his background and contribution. With ocular dryness as our issue, we began investigating the cause. We found that it did not necessarily come from inadequate tears, as most people thought, but could also come from inadequate oil secretion. What we described was a syndrome of ocular dryness and contact lens intolerance due to meibomian gland obstruction, which in turn led to drying and inadequate ocular surface lubrication.2 Only in the last few years has the importance of this become widely recognized.

TOS What are your current research activities? KORB We are again working on meibomian gland dysfunction, but with newly available methods. The French philosopher Nicole said there are very few original ideas, and it’s wise on occasion to revisit the work of the past. This is because prior work often fails to achieve its full fruition because the technical means were not available to carry the project forward. Today there are great new techniques in the realm of science, ophthalmology, and optometry that are enabling us to better understand secretion processes of the meibomian glands. Our group has a series of publications that will address a broader spectrum of meibomian gland physiology. Recently our group, led by Dr. Caroline Blackie, has investigated the time required to fully drain a meibomian gland of liquid secretion and the time it then takes for that gland to regain secretory function. We invented new instruments to allow expression of one or more meibomian glands with controlled pressure, which allowed us to completely drain the gland. Once it is fully drained, we have found that it takes 2.5 hours to produce the first visible secretion. To fully replenish the gland probably takes 8 hours. Clearly one of the reasons we need to close our eyes and sleep is to allow these glands to refill. This work also provides insight into the kind of problems that will always develop in extremely dry conditions, such as those experienced during long airplane flights. We have also found significant differences in the function of these glands, approximately 25 of which are found in the lower lid and another 25 in the upper. We found, for instance, that the glands on the nasal side produce the most secretion, and those on the temporal side produce the least. This was a complete surprise to me. I would have expected the opposite because when you blink, the lids touch first on the temporal side. In addition, we’ve found that no lower eyelid has all of its approximately

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PERSONAL PROFILE

25 glands working all the time. We don’t know yet whether this is because some are obstructed or whether there is a rhythm to their function that we have yet to understand. All of this is very exciting in that it changes our perspective and leads to still more questions for us and others to pursue. And this may be the greatest pleasure of all: to make observations and see others go forward with them to further medical knowledge. ; REFERENCES 1. Allansmith MR, Korb DR, Greiner JV, Henriquez AS, Simon MA, Finnemore VM. Giant papillary conjunctivitis in contact lens wearers. Am J Ophthalmol. 1977 May;83(5):697-708 2. Korb DR, Henriquez AS. Meibomian gland dysfunction and contact lens intolerance, J Am Optom Assoc. 1980;51(3):243-51

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