LASIK surgery has revolutionized vision care for millions of people with refractive vision problems, such as myopia, hyperopia, and astigmatism. But, despite its popularity and widespread use, LASIK — which stands for laser in situ keratomileusis — isn’t always the best choice for every patient.
At Advanced Eye Center in Hialeah, Florida, Rodrigo Belalcazar, MD, offers both LASIK and PRK (photorefractive keratectomy) for patients with refractive vision problems. If you’ve been thinking about having your vision corrected with laser eye surgery, here’s how these two techniques compare.
Corneal refractive surgery 101
Both LASIK and PRK are types of laser vision correction surgery, but the way they achieve clearer vision is a little different. Before delving into those differences, it’s important to understand how corneal refractive surgery works.
When we see, light passes through the cornea — the clear covering of the eye — to the opening in the iris, and all the way to the light-sensitive retina at the back of the eye. Tiny rod and cone cells distinguish light and shadows and send this information to the brain via the optic nerve. The brain, in turn, translates the data into the images we see.
When the cornea is round, light is bent in a very precise way as it passes through to the retina, creating clear, crisp images. But, if the cornea is misshapen — even slightly — the images you see may be cloudy or blurry. These vision problems are called refractive errors, and they include the following:
- Myopia (nearsightedness)
- Hyperopia (farsightedness)
- Astigmatism (distorted or blurred vision at any distance)
- Presbyopia (blurry vision that occurs with age)
Corneal refractive surgery corrects refractive errors by reshaping the cornea so light can bend correctly.
LASIK vs. PRK
Although LASIK is perhaps the most well-known type of refractive surgery, it’s certainly not the only approach for vision correction. In fact, LASIK isn’t a good choice for every patient. Some patients are much better suited to other types of corneal refractive surgery, such as PRK. Here’s why.
How LASIK surgery is performed
LASIK surgery begins by creating a thin flap of tissue in your cornea. This flap is folded back during surgery to enable the laser to reach the under layers of the cornea and reshape them. After reshaping, the flap is folded back over the eye, where it acts as a kind of natural bandage.
How PRK surgery is performed
PRK also uses a laser to reshape the lower layers of corneal tissue. However, instead of making a flap, it uses a special technique to gently remove the very upper layer of tissue, called the epithelial layer. After reshaping, you wear a special contact lens to protect your eye while the epithelial layer regrows.
Cases where PRK surgery might be the better option
In order to create the flap used in LASIK, your cornea has to be a certain thickness. Otherwise, there wouldn’t be enough corneal tissue to create the flap. Because PRK doesn’t use a flap, it can be a better choice for people with thinner corneas.
PRK can also be a better option for people with dry eye syndrome, since LASIK is associated with a higher incidence of dry eyes following surgery.
Laser eye surgery can correct vision problems and help reduce or even eliminate the need for glasses or contact lenses. If you’d like to learn how refractive eye surgery can help you enjoy clearer vision, book an appointment online or over the phone with Advanced Eye Center today.