Usually beginning at about age 40, a reduction in the eye's natural ability to focus flexibly results in many people needing to wear bifocals or multi-focal contact lenses in order to manage seeing clearly at distances both near and far. This condition, in which the eyes exhibit a progressively diminished capacity to focus on near objects with age, is called presbyopia.
Recent advances in corneal ablation technique using Excimer lasers allow ophthalmologists to correct for presbyopia, giving patients the ability to see near objects clearly without glasses or contact lenses. In general, presbyopic surgery, also known as PresbyLASIK, and Multi-focal LASIK, applies the principles of LASIK surgery to create a multi-focal corneal surface, with a central area which is hyperpositive for near vision, leaving the mid-peripheral cornea for far vision.
PresbyLASIK, or Multi-focal LASIK, which allows patients to retain binocular vision, is currently under clinical trials in the US and has not yet been approved for general treatment by the FDA. However, many ophthalmologists are hopeful that trial data and the success of the technique in other countries will help make the procedure available soon to US presbyopia patients.