Glossary: Presbyopia With increasing age, the lens of the eye becomes harder and is less able to change shape. This results in increasing difficulty in seeing at close distances, and is known as presbyopia. Astigmatism Cataracts Clear lens extraction (CLE) Corneal collagen cross-linking (CXL) Corneal rings Corneal topography and corneal mapping Corneal transplant DALK Dilated Eye Exam Dry eyes Infection Keratometry Lasik Lens MEL 90 excimer laser ORA (Ocular Response Analyser) Pain Phakic intraocular lenses (IOL) PKP (Penetrating Keratoplasty) Pterygium Regression Suitability assessment Technology VISUMAX femtosecond laser