Dr. John Berdahl MD is a leading cataract surgeon practicing at Vance Thompson Vision in Sioux Falls, South Dakota. Fellowship trained in cornea, glaucoma, and refractive surgery, Dr. Berdahl has performed more than 35,000 eye surgeries around the globe. His published work has primarily focused on the fundamental causes of Glaucoma, Minimally Invasive Glaucoma Surgery, and Astigmatism Management, during and after cataract surgery, and he has been involved in numerous FDA monitored clinical trials on some of the most exciting technologies in ophthalmology.