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Two Locations To Serve You!

Denison 903-465-3815 Van Alstyne 903-482-0090
Home ยป Our Eye Doctors

Our Eye Doctors

Eye care professionals specialize in understanding how the human eye really works, as well as diseases and conditions that affect your vision – many of which do not have obvious symptoms. Eye doctors know how age and risk factors affect vision over time for young and old, and they understand the benefits and features of corrective lenses including eyeglasses and contacts.

Our optometrists take the time to explain the results of your eye exam, describe your options and listen to your eye care needs. Because maintaining good eye health is an ongoing partnership, we encourage you to ask questions and share your health information, which could be vital to monitoring, diagnosing and treating potential vision problems.

Meet our doctors:


Dr. Dennis Nietling

Dr. Nietling did his undergraduate work at Michigan State University and Ferris State University. He graduated from Ferris State University with a Doctorate of Optometry in 1981. In 1982 he purchased this practice from Dr. A.J. Levinson and has had the office in Denison for over 30 years. Nietling Optical’s second location in Van Alstyne was opened in 2003.

Dr. Nietling is a licensed therapeutic optometrist and glaucoma specialist. He is a member of the American Optometric Association, and also a member of the Chamber of Commerce in Denison, Van Alstyne, Howe, and Gunter. He is a Denison resident along with his wife, Regina, and he has four children.


Dr. D. Gary Thomas

Dr. Thomas is a Graduate of the University of Houston College Of Optometry. He is board certified in Developmental Optometry as a fellow Emeritus of the College of Optometrist in Vision Development and a Diplomat in the American Board of Optometry.

Dr. Thomas has practiced Therapeutic Optometry in Northeast Texas for over forty years and lives in Tanglewood Hills.