Are you a candidate for LASIK surgery?

LASIK is a popular procedure but it's not suitable for everyone with vision problems. Your doctor will determine if the surgery could benefit you during a thorough evaluation. Here's what you can expect during the evaluation.  

Vision evaluation

The process of determining whether you are a good candidate for LASIK will start with a thorough vision evaluation. This is an extremely important step. If your corneas are not thick enough or you have existing issues such as dry eye, LASIK could create more problems than it solves.

If you wear soft contact lenses, switch to glasses during the two weeks before your evaluation. Other types of lenses should stay out for three to four weeks. The reason for this is that contact lenses change the shape of your cornea. Wearing them right before your evaluation could give your ophthalmologist an inaccurate measurement, potentially leading to poor surgical results.

Medical history

During the evaluation, your doctor will go over your medical history. Conditions such as diabetes, certain autoimmune diseases, and inflammation in the cornea could make the surgery riskier and have a negative effect on the outcome. You'll also be asked which medications you take. Some medicines, such as the migraine drug sumatriptan (Imitrex) and the acne medicine isotretinoin (Absorica), could disrupt healing or contribute to more eye dryness. The ophthalmologist will check your visual acuity—how clearly you see at a distance and close up.

Dilated eye exam

You can also expect to have a complete dilated eye exam, in which your ophthalmologist uses drops to widen your pupils and looks inside your eye for dry eye, problems with your cornea or iris, cataracts, and retinal tears. The exam will also include a look at your pupil size (having larger pupils might increase your risk for glare and halos after surgery), and the shape and thickness of your cornea.

During the exam is the time to ask any questions—before you sign the informed consent form indicating your agreement to go ahead with the procedure.

Topography

If you do go ahead with LASIK, your ophthalmologist will map out your corneas in three dimensions, a process called topography or tomography. Some of the more advanced LASIK surgeons use wavefront analysis technology.

A device called an aberrometer measures the light passing through your lens and cornea and produces a custom map of tiny imperfections, called higher-order aberrations, in your eyes. Using wavefront-guided LASIK, the surgeon can provide more precise and personalized vision correction, and possibly a better outcome.

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