LASIK is a commonly performed refractive procedure to reduce or eliminate the need for eye glasses. It involves creating a flap in the outer most layer of the cornea called the epithelium, lifting it up and then reshaping the inner layers employing a laser. By changing the shape of the cornea, light can be focused on to the retina thus eliminating the need for eye glasses or contact lenses.

A comprehensive visual evaluation must always be performed to ascertain if there are any pathological issues or dystrophies which can adversely affect the results of the refractive procedure. Misdiagnosis or missing a corneal dystrophy can have devastating consequences during the procedure.

The flap in LASIK can be created with the use of either a lathe or a laser called Intralase. Under normal circumstances the flap is made, and lifted without any problems; it retains its shape and form. If there is an underlying condition such as a “Map Dot Fingerprint" corneal dystrophy, then when the flap is lifted up it will fall apart and break into pieces like paper tissue in water. When this occurs the outer most layer of the cornea can be lost; resulting is a devastating surgical complication. The recuperation will be long, painful and may result in permanently reduced vision. Frequently, when a dystrophy is missed during the presurgical testing and a flap is created, the procedure must be aborted and a contact lens placed on the eye to keep the fragmented flap in place while it heals. Hopefully, the flap is never lifted up, and will therefore heal without incident. Once it is lifted, the trouble begins.

Therefore, it is critical that the surgeon very carefully evaluate the cornea prior to surgery to rule out any dystrophy that will destroy the flap. When such a condition is found, PRK is the procedure of choice. In that case, the epithelium is brushed away and there is no chance of a dystrophy causing any issues. As always, selecting an experienced well trained refractive surgeon is critical to achieving the best results.