• Trans-Epithelial PRK Description: This video demonstrates a trans-epithelial topography-guided PRK using the WaveLight EX500 excimer laser. The first treatment was many years ago and this enhancement treatment set out to treat the residual hyperopia and the decentred optical zone. Submitted by Dr. Arthur Cummings (Ireland) Subspecialty: Refractive Management / Intervention Level: Intermediate Uploaded By: ISRS Multimedia Library