LASIK Candidacy – Retinal Problems

LASIK vision correction is not performed on the retina, but on the cornea, the clear front part of the eye. But vision depends on the retina and retinal problems can disqualify a person from LASIK.

The retina is the eye’s “camera film” in that its light-sensitive cells receive images carried in by light. They convert the images to electrical energy. Attached to each retinal cell is a tiny fiber that is part of the optic nerve. Each of these fibers picks up the electrical energy from its retinal cell and carries it to the brain.

The optic nerve, as it leaves the retina, consists of millions of these tiny fibers. The nerve connects to the retina at the eye’s blind spot – blind because there are no retinal cells there.

Retinal Holes and Detachment

In front of the retina is a cavity filled with a clear gel called vitreous humor or just “vitreous”. It is attached to the retina. Behind the retina is the choroid, a layer in the eyeball wall. It contains blood vessels that nourish the retina.

Sometimes the vitreous separates from the retina. Often this is not significant but in some cases it pulls part of the retina with it. Then vitreous can leak into the space behind the detached part of the retina, separating it from its blood supply in the choroid. When this happens you might experience:

• Sudden numbers of floaters (stringy shapes floating in your vision)
• Flashes of light
• A grayness or darkness in your vision

Although these are sometimes normal, they can be a sign of a potentially serious condition.

If only a small area is detached it is more easily treated, and these are known as retinal holes. When they go untreated, more of the retina can peel away from the choroid, even the entire retina, and blindness is the result. If the retina is detached on its periphery, you may not notice anything. If it is detached in its central area (macula), blindness could result. There are treatments for retinal detachment and vision can be restored, although it may not be as sharp is it was previously.

If you have had a retinal hole or detachment in the past, you may be disqualified for LASIK, even if it was successfully treated at the time. A detachment could occur again and undo the benefits of any LASIK treatment.

Retinitis Pigmentosa

Retinitis Pigmentosa is the name for a group of hereditary degenerative conditions which progress slowly. They cause decreased night vision, eventually tunnel vision and finally blindness. Abnormalities occur in the light-sensitive cells of the retina, preventing them from receiving light. There is currently no cure, although high doses of Vitamin A can slow the progression of this condition.

A person with retinitis pigmentosa would not be a good candidate for LASIK, as there is no way to prevent the vision deterioration, and any improvement made by a LASIK procedure would be negated.

Diabetic Retinopathy

Diabetes is a systemic disease with unstable blood sugar levels. One of its aspects is retinal damage which can eventually cause blindness. The tiny blood vessels nourishing the retina weaken and start to leak. That reduces blood circulation to the retinal cells and the body tries to compensate by creating new blood vessels. But these are fragile and also leak. The result is increasingly blurry vision as more leakage occurs.

The macula is the central area of the retina which gives us our direct vision – enables us to see small details clearly. Leaking blood can cause the macula to swell, further distorting vision.

Diabetic retinopathy cannot be cured but it can be managed. If you have diabetes, your eye surgeon will examine your eyes carefully to determine whether LASIK could be successfully performed.

Cystoid Macular Edema (CME)

CME is a condition where many cyst-like areas appear on the macula, each filled with fluid. The causes are not well understood but it occurs (rarely) after some cataract surgeries, as part of diabetic eye damage, and in connection with some eye infections.

Central vision becomes blurry but peripheral vision remains unaffected. There is no pain and it can be treated in various ways, according to its cause. In a person considering LASIK vision correction, CME would be potentially disqualifying.

If you would like to be evaluated as a LASIK candidate, please contact us for an experienced and well-qualified LASIK surgeon today.