Invalid word or phrase. Visit the Begin Exploring page for ways to select cases.

About the David G. Cogan Ophthalmic Pathology Collection

by Dr. Carl Kupfer

The Cogan Collection, named after David Glendenning Cogan, is a collection of clinical ophthalmic cases and their pathology. The clinical description and photographs of the cases and the pathology were collected by Dr. Cogan during his career as both a clinical and research ophthalmologist, first as Director of the Howe Laboratory and Professor at the Massachusetts Eye and Ear Infirmary of the Harvard Medical School, and for 20 years, Senior Scientist at the National Eye Institute (NEI) of the National Institutes of Health (NIH).

In April 1993, Dr. Cogan asked me to preserve this collection by archiving case histories and histopathology slides as a teaching collection of ophthalmic pathology. Without knowing the details of this collection, but having the highest respect for Dr. Cogan as a scientist, clinician, and friend, I readily agreed to undertake this task. After his death in September 1993, I attempted to fulfill this commitment, but my duties as Director of the NEI occupied the vast bulk of my time. However, by 2000 it became apparent that if I was to honor my promise to Dr. Cogan, I would need to relinquish my position as Director and turn to the Cogan Collection fulltime.

In May 2000, I stepped down from the NEI Directorship and began assessing the Cogan Collection. I was amazed to find that this collection consisted of over 6,000 clinical cases and almost 60,000 kodachrome transparencies documenting both the clinical appearance and the histopathology. It was clear that some cases could be excluded, such as ones that had already been published or presented at one of the local pathology meetings, or were missing the microscopic histopathology slides; or were so old that the slides had faded. Also set aside were the cases I did best to identify that Dr. Cogan had collected during his attendance at the Verhoeff Pathology Society, the Eastern Pathology Society of the United States, and the European Ophthalmic Pathology Society. Still, some 1040 cases along with some 3300 slides remained. This constitutes the Cogan Collection.

From the beginning of this undertaking, what I found most attractive was the opportunity to put the Cogan Collection on the internet so that anyone in the world with internet access could call up the material and use it for study, teaching, and other purposes. Without a doubt, understanding pathology enhances the ability to prevent, diagnose, and treat diseases of the eye and visual system. Knowledge of pathology is absolutely essential for the most competent performance of both the research and clinical ophthalmologist.

The collection in its present form covers ophthalmic pathology. There is special emphasis on areas that Dr. Cogan was particularly interested in, such as the pathology of corneal transparency and its relevancy to the pathogenesis of atherosclerosis, and the changes in the small blood vessels in diabetic retinopathy, as studied in trypsin digestions of the retina. This technique permitted visualization of the pathology in the arteries, veins, and capillaries, and was developed by Dr. Toichiro Kuwabara. Drs. Cogan and Kuwabara, along with Dr. Jin Kinoshita, established the hypothesis of selective loss of capillary intramural pericyte cells causing diabetic damage and resulting in small vessel disease. This contribution was among many contributions that are recorded in over 500 publications, the vast majority having Dr. Cogan as the first author.

I am indebted to those who assisted me in this major effort, most notably Dr. Chi-Chao Chan who reviewed all the histopathology , Ms. Alene Robinson, Ms. Tania Estes, and Ms. Mara Parker for accurately transcribing Dr. Cogan's descriptions of the clinical cases and the histopathology, and Mr. Don Smith who carried the major responsibility of designing and overseeing the computer aspects of this collection. Finally, Mr. Fausto Vela provided computer oversight and support, especially for my efforts in completing this formidable task in the relatively short period of four years.

Transcript of Launch for the David G. Cogan Ophthalmic Pathology Collection

Lawton Chiles International House
Bethesda, Maryland
June 13, 2005
Welcome and Introductions

Dr. Paul A. Sieving, Director, NEI, welcomed approximately 30 attendees to the official launch of the David G. Cogan Ophthalmic Pathology Collection. In attendance were Dr. Cogan's daughters, Priscilla Cogan and Polly Parson, his son-in-law, William Parson, and several members of Dr. Toichiro Kuwabara's family. Dr. Kuwabara was a close colleague and collaborator of Dr. Cogan's.

Dr. Sieving described a number of important contributions made by Dr. Cogan in the field of ophthalmic pathology and described a few of the many honors and recognitions that Dr. Cogan received over his long career.

Lastly, Dr. Sieving thanked Dr. Carl Kupfer, Founding Director of NEI, for organizing the collection, which is intended for both national and international use through internet access at this website.

Overview of the Collection

Dr. Carl Kupfer expressed his appreciation to those who helped him archive Dr. Cogan's material on ophthalmic clinical findings and histopathology. He reviewed the outline of the Collection's Web site and how cases can be searched by case number, anatomical location, clinical description, and histopathology description. Cases also can be found by descriptions of normal slides and by entering a word or phrase. He stated that the Internet tool would prove invaluable to those interested in ophthalmic pathology, especially those just entering the field.

Dr. Kupfer demonstrated the use of the site and reviewed several cases pertaining to areas of research by Drs. Cogan and Kuwabara. The first case was a patient with diabetic retinopathy with photographs showing selective loss of retinal pericytes. The early loss of pericytes is a hallmark of this disease, as was first demonstrated by Drs. Cogan and Kuwabara.

A group of cases was presented on cystinosis. Dr. Kupfer explained that Dr. Cogan was very interested in these cases, which he began seeing in the 1940s, before the advent of kidney transplantations and treatment using cysteamine. The histopathology and transmission electron microscopy clearly showed characteristic needle-shaped crystals in the cornea, as well as in almost all other ocular tissues.

Dr. Kupfer concluded by saying that the newly consolidated collection will be made known to ophthalmology and pathology organizations around the world and will enhance the ability of clinical ophthalmologists to improve the prevention, diagnosis, and treatment of eye disease.


Dr. Priscilla Cogan thanked Dr. Sieving for inviting her family to the ceremony and expressed appreciation to Dr. Kupfer for his work on archiving her father's clinical cases. She emphasized the importance of Dr. Kuwabara's contributions to the collection. Dr. Cogan shared her belief that her father would be very excited about the advent of the Internet and the access it affords to study his life's work.

Drs. Daniel M. Albert, Thaddeus P. Dryja, and Mark O.M. Tso thanked the NEI for inviting them to the event and for perpetuating the memory and preserving the teachings and bench to bedside research of Dr. Cogan.

Stories about Dr. Cogan and his family and professional life were shared by his daughters, son-in-law, and former associates. Dr. Kupfer noted how fortunate the NEI was to have had someone of Dr. Cogan's caliber who gave generously of his knowledge and time in teaching young scientists at the Institute. After inviting everyone present to examine the Internet display, Dr. Sieving thanked everyone for attending and adjourned the proceeding.

Link to the NEI Press Release: National Eye Institute Launches David G. Cogan Ophthalmic Pathology Collection