• College: Tulane University, Louisiana
• Internship: Parkland Hospital, Texas
• Medical School: Tulane University Medical School
• Residency: University of Texas Medical Branch Texas
• Fellowship: Glaucoma with John Cairns, Cambridge
• Clinical Faculty: Southwestern Medical School, Texas
• Military Service: U.S. Public Health Service

Dr. Duncan was born in New Orleans but was raised in San Antonio, Texas. He graduated from Tulane undergraduate school in 3 years and remained at Tulane for medical school.  He graduated from medical school with honors and was in the honor society Alpha Omega Alpha.

He lived five years in Galveston which included three years as a resident at the University of Texas Medical Branch and two years on the faculty while he also served his military time in the U.S. Public Health Services. He moved to Cambridge, England where he did a glaucoma fellowship with John Cairns who was famous for inventing the trabeculectomy operation which is still the gold standard for glaucoma in the world.

In 1976, he moved to Lufkin, Texas where he began practice with John C. Koch, MD. The clinic originally known as The Eye Clinic became known as East Texas Eye Associates.

Since his arrival in East Texas, Dr. Duncan has pioneered phacoemulsification, argon laser, YAG laser, Holmium laser, and diode laser for treatment of eye disease. He was the first to establish a surgery center in Deep East Texas, preceding all others by six years.

Dr. Duncan has been a longtime leader in medicine, serving as President of the Angelina County Medical Society, treasurer of the Texas Ophthalmological Association, councilor to the Texas Ophthalmological Association, councilor to the American Academy of Ophthalmology, and delegate to the Texas Medical Association House of Delegates.

He has fought for years for equal treatment under the Medicare program for rural medicine versus the large cities. In 2008, he was elected Outstanding Ophthalmologist in Texas by the Texas Ophthalmological Association for his support of the practice of ophthalmology.

Dr. Duncan has been married to his wife, Mary, since 1968 and they have four sons. Mary is the former Mary Stripling from Nacogdoches.