Carter Eye Lasik Vision Correction Blog

When you have your vision corrected with a LASIK surgery or one of its alternatives, the laser reshapes the cornea. That is the front clear covering over the iris and pupil. That reshaping changes the way the cornea bends light as it enters the eye, which in turn changes the way images focus on the eye’s “camera film”, the retina at the back of the eye.

That laser reshaping of the cornea’s curvature is permanent. It is done on the cornea’s middle layer, not on the top surface. The surface (epithelium) is an unstable layer. Part of its function is to protect the eye from dust and foreign bodies. The eye’s tears flow over it to wash such things away, and the cells in the surface layer replace themselves continually.

In that respect it resembles the skin, where the surface layer is also a protective one, and also continually replaces its old discarded cells with new ones that rise from a deeper layer.

When the cornea’s middle layer is reshaped to focus light clearly on to the retina, the eyes now have permanently clear vision – until mid-life. After the age of about 40, presbyopia begins to develop, and near vision starts to become blurry. This is an age-related condition that happens to everybody. The problem in not in the cornea’s curvature, but in the lens.

Causes of presbyopia are not fully understood, but the favored long-standing theory is that the lens becomes stiffer with age. It gradually loses its ability to steepen its curvature. Both the cornea and the lens are focusing structures. The LASIK-corrected cornea will continue to focus well but the lens becomes less able to “accommodate” to different distances. Accommodation is the ability to switch focus from near to far to intermediate and see everything in focus.

Presbyopia is most often and most easily corrected with reading glasses, but there are other possible treatments, such as an intraocular lens.

If you would like to learn more about LASIK and its likely results in your own case, please call or email LASIK surgeon Dr. Harvey Carter today for a free personal consultation. We look forward to working with you.