LASIK versus PRK?
LASIK (laser-assisted in situ keratomileusis) is a safe, reliable and painless way to improve vision and reduce or eliminate the need to wear glasses or contact lenses. LASIK changes the way light is bent, or refracted, as it passes through the cornea so that it focuses properly on the retina and objects can be seen clearly.
During the procedure the excimer laser creates a thin flap in the surface of the cornea. Patients are given anesthesia so they can’t feel the instruments. Next, the flap is then lifted and the laser beam reshapes the cornea’s curvature to improve vision. The flap is then closed and covered with a protective contact lens.
The entire procedure takes approximately 15 minutes per eye, and patients are often ready to leave within an hour or two. The flap heals on its own within a few days with no need for stitches.
A common complaint after surgery is sensitivity to light, but this will subside. Antibiotic eye drops will be prescribed for a few days, along with any other post-operative instructions. Full recovery takes a few weeks.
PRK or photorefractive keratectomy is one of the safest and most time-tested laser vision correction procedures available. Before LASIK, PRK was the most common refractive surgery procedure. Like LASIK, it reshapes the cornea to improve vision. PRK is now used mainly for patients with large pupils or thin corneas.
The first step in PRK is to remove the epithelium, a thin layer protecting the cornea. Then the surgeon uses an excimer laser to vaporize a small amount from the top of the cornea. LASIK, by contrast, cuts a deep flap in the cornea using a sharp microkeratome blade. This weakens the cornea, makes it difficult to replace the flap in precisely the right place, and can cause other complications including flap irregularity, epithelial ingrowth and corneal ectasia. PRK avoids these risks.
Studies have shown that 90-95% of patients with a correction of up to -6.00 diopters achieve vision of 20/40 after PRK, and up to 70% achieve 20/20. Patients needing less correction generally achieve better results. The risks of PRK include infection, haze, slow healing, scarring, over- or under-correction of the visual condition, and development of astigmatism.
Final takeaway: Both LASIK and PRK can be safe procedures. You may be a better candidate for LASIK or PRK, depending on your prescription and other factors, which will be discussed with you at the time of your evaluation.