All professionals at Childrens Eye Center of South Texas, PA maintain the highest levels of accreditation and pursue ongoing education to stay abreast of the latest trends in the medical field. Read on to learn more about our staff's experience and training.

Charles S. McCash, M.D.

Charles McCash, M.D. is the founder of Children’s Eye Center of South Texas, P.A. Dr. McCash is originally from Texarkana, Texas, and received his undergraduate education at Texas Christian University in Fort Worth, Texas. After graduating from the University of Texas Southwestern Medical Center in Dallas, Texas, he performed his internship at Parkland Hospital in Dallas, and his residency in Ophthalmology at the University of Texas Health Science Center at Houston. He then received his subspecialty training in Pediatric Ophthalmology and Strabismus (eye alignment disorders and double vision) in Houston.

Dr. McCash moved to San Antonio in 1997, and started Children’s Eye Center of South Texas, P.A. in 1998. He is a Member of the American Association for Pediatric Ophthalmology and Strabismus, a Fellow of the American Academy of Ophthalmology, and a Member of the Texas Medical Association, the Texas Ophthalmology Association, and the Bexar County Medical Society. He is also an Adjunct Associate Professor of Ophthalmology at the University of Texas Health Science Center at San Antonio.

Dr. McCash’s family includes his wife, Beth, 3 daughters (Claire, Katie, and Mary Grace), 2 dogs, a whole bunch of cats, some hermit crabs, and whatever else his daughters and wife decide to feed.

Claire Castleberry Hennessey, C.O.

Claire, originally from Lufkin, Texas, graduated with a Bachelor of Science degree in Community Health from Texas A&M University. Upon graduation, she was accepted into the Orthoptic Fellowship program at Washington University School of Medicine in St. Louis, Missouri. There, Claire completed a two-year master’s level training and successfully passed a series of board examinations to receive her certification in 2002.

Claire has previously worked at St. Louis Children’s Hospital Eye Center where she served as a clinical and academic orthoptist working in both pediatric and neuro-ophthalmology. She was an instructor for the Orthoptic Fellowship and Ophthalmology Residency Programs at Washington University. Also, Claire was actively involved in research as she has had several publications in various ophthalmology journals and has given presentations and instruction courses at professional education meetings hosted by the American Academy of Ophthalmology, American Association of Certified Orthoptists, American Association for Pediatric Ophthalmology and Strabismus, and the Texas Society for Pediatric Ophthalmology.

Currently, Claire is the Chief Orthoptist at Children’s Eye Center and also serves as an instructor for the Ophthalmology Residency Program at the University of Texas Health Science Center San Antonio. She is actively involved in various ophthalmology related organizations such as: the American Association of Certified Orthoptists, the American Association for Pediatric Ophthalmology and Strabismus, and the American Academy of Pediatrics.

Keith M. Williams, OD

Dr. Williams was born and raised in Texas. He attended Texas A&M University at College Station where he graduated in 1996 with a Bachelors Degree in Biomedical Science. He then enrolled at the University of Houston, College of Optometry where he graduated Magna Cum Laude with an OD in 2001. He completed his rotations at St. Joseph Hospital in Houston as well as Mann-Berkeley Eye Center.