About Our Practice

Mabee Eye Clinic’s history began with two brothers from Iowa who both graduated from the University of Iowa with a specialty in eye, ear, nose, and throat. Those two brothers, Dr. Oscar Judson Mabee and Dr. Don Mabee moved to Mitchell, South Dakota in 1925. They established an eye, ear, nose, and throat practice in the Medical Arts Building located on the main street in Mitchell.

Dr. Oscar and his wife, Hilda, had two children. The oldest, Judson Oscar Mabee graduated from medical school at the University of South Dakota. He completed his ophthalmology training at the Manhattan Eye, Ear and Throat Hospital in New York City and returned to Mitchell with his wife, Marilyn (Boots), in 1961 to practice ophthalmology in the downtown medical facility with his father.

Dr. Judd Mabee soon realized the need for quality eye care in Mitchell, a town of nearly 15,000, and a large, rural surrounding area of 80,000. The demands for eye care made it necessary to move to a larger facility. A new clinic was constructed at 305 N. Sanborn in 1969. Mabee Eye Clinic included a reception area, business office, an optical shop and lab, five exam rooms, space for two offices, and storage.

The Mabee Eye Clinic became incorporated with Dr. Oscar J. Mabee, Dr. Judson 0. Mabee, and Dr. Harvard Lewis as stockholders in 1968. Dr. Judson Mabee became the sole stockholder in 1972. The Mabee Eye Clinic building included space that was rented as a dental practice until 1996. When the dentist occupying the space left the building to construct his own clinic, Mabee Eye Clinic remodeled the vacated space thus expanding the reception area, the optical department and lab.

Dr. Judson Mabee raised the level of ophthalmological care in Mitchell and the surrounding area. During his thirty plus year career, he performed many strabismus and cataract surgeries. He performed the first corneal transplant in the state of South Dakota as well as performing retinal detachment surgeries during his initial years in practice.

The Mabee physicians were well regarded for their caring and precise medical services. Needing assistance in providing complete eye care to his patients, Dr. Judson Mabee arranged with Gene Liudahl, O.D. to join the practice as an independent contractor at the Mabee Eye Clinic. Dr. Liudahl came to the Clinic in 1967. Dr. Oscar Mabee retired in 1982.

The demand for quality eye care and surgical procedures prompted Dr. Mabee to recruit an additional, board certified ophthalmologist. Dr. Ray T. Birkenkamp, a graduate of Southern Illinois University Medical School, completed his ophthalmology training at St. Louis University Hospitals in 1983. He and his wife, Kris, moved to Mitchell at that time and Dr. Birkenkamp became an partner of Dr. Mabee’s.

Dr. Birkenkamp performed the first laser eye surgery in Mitchell as well as the first phacoemulsification cataract surgery. He performed over 10,000 cataract surgeries during his thirty plus years of providing ophthalmological surgical care to the Mitchell area.
The Mabee Clinic continued to expand and in the1980’s had established satellite offices in Parkston, Chamberlain, and Huron. With the added demands, Dr. Gene Liudahl recruited Dr. Gregg Bleeker to assist in patient care. Dr. Gregg Bleeker was a 1983 graduate of Illinois College of Optometry and had spent his first 3 years practicing optometry at Malmsrom Air Force Base Hospital near Great Falls, Montana. Dr. Gregg Bleeker joined the Mabee Clinic in October 1986 – the opening weekend of pheasant hunting season. Dr. Liudahl and Dr. Bleeker established an additional satellite office July 1987 in Salem – which is still providing complete eye care to the community of Salem, SD.

Dr. Judson Mabee retired from ophthalmology and the Mabee Clinic in December 1996. He and his wife Marilyn(Boots) were killed in a tragic float plane accident in Canada in June 1997.

As Dr. Gene Liudahl neared retirement, Dr. Bleeker recruited Dr. Glen Nydam to join the Mabee Clinic in June 2000. Dr. Nydam was a 1996 graduate of Southern California College of Optometry and had spent his first 4 years practicing optometry at Ft. Leonard Wood Army Hospital in Missouri. Dr. Gene Liudahl then retired from optometry and the Mabee Clinic in August of 2000 and soon moved to Rapid City.

Dr. Ray Birkenkamp retired from ophthalmology and the Mabee Clinic in September 2017.

In May 2018, Dr. Nicholas J. Wenande, O.D., F.A.A.O., joined the Mabee Eye Clinic.

Greg Bleeker

Gregg A. Bleeker, O.D.

Dr. Bleeker was born in Brookings, South Dakota, while his father attended SDSU, and was raised in Pipestone, Minnesota. He graduated with honors from Dordt College in Sioux Center, Iowa. In 1979, Dr. Bleeker enrolled at Illinois College of Optometry in Chicago, Illinois and graduated as valedictorian of his 1983 optometry class. He was able to attend optometry school by accepting a United States Air Force Health Professional Scholarship. Upon completion of optometry school, Dr. Bleeker served as an optometrist and Captain with the USAF for a 3-year tour of active duty at Malmstrom Air Force Hospital near Great Falls, Montana. In October of 1986, he moved to Mitchell to join the Mabee Eye Clinic. Dr. Bleeker is a Board Certified Optometrist and is fully certified to prescribe eye medications. He is an active member of the SD Optometric Society and the American Optometric Association. He is married to Janet (Crockett) and has two children, Adam and Ellie. His interests are water skiing, boating, downhill skiing, running, and music.


Glen D. Nydam, O.D.

Dr. Nydam was raised in Platte, South Dakota. He received his Bachelor of Science degree, with honors from Dordt College in Sioux Center, Iowa. He is a 1996 honors graduate of Southern California College of Optometry where he was awarded the Frank A. Brazelton Award for clinical excellence. Dr. Nydam has completed ocular disease, contact lens, and low vision internships at the Optometric Center of Los Angeles; Tripler Army Medical Center, Hawaii; the Santa Monica Center for the Partially Sighted; and Kaiser Permanente, Fontana, California.

Dr. Nydam attended optometry school through a scholarship with the U.S. Army. During his four years of military service, he served as Chief of Optometry Services in Shape, Belgium and Tuzla, Bosnia. He also served as a staff optometrist at Ft. Leonard Wood Army Community Hospital in Missouri. In June of 2000, he joined the Mabee Eye Clinic.

Dr. Nydam is board certified in Optometry by the National Board of Examiners in Optometry and is an active member of the American Optometric Association, and the South Dakota Optometric Association. Dr. Nydam and his wife, Jill, have four children, Kendra, Braeden, Reegan, and Addison. His interests include hunting, travel, music and his family.


Nicholas J. Wenande O.D., F.A.A.O.

Dr. Nicholas Wenande was raised in Mitchell, South Dakota. He holds a Bachelor of Science degree in Biology and Chemistry from Mount Marty College in Yankton, SD and a Doctorate of Optometry from the University of Missouri- St. Louis College of Optometry. Upon completion of his education, Dr. Wenande spent three years in the United States Army as assistant chief of optometric services at Reynolds Army Health Clinic, Fort Sill, OK.

Dr. Wenande is board certified in Optometry by the National Board of Examiners. He is an active member of the American Optometric Association, the South Dakota Optometric Association, and the Scleral Contact Lens Society. He holds a fellowship in the American Academy of Optometry, a distinction held by only fifteen optometrists in the state of South Dakota. Dr. Wenande is a strong believer in customer service and offering a positive patient experience. He believes superior diagnostic technologies and clinical excellence should be the expectation of all of his patients. Dr. Wenande is excited to be back in Mitchell serving his community and providing a personalized approach to meeting his patient’s needs.

Nick and his wife Laura (Osterloo) have two children, Emery and Adler. Laura is a photographer and owns L.O. Imijri Photography & Design. In their free time, their family enjoys being active in their community, watching sports, and enjoying outdoor activities.