LASIK 101: What You Need to Know

August 28, 2020

One of the most common questions we hear is, “I’ve been thinking about LASIK; Am I a candidate for it?” Unfortunately, it is a little more complicated than that, but we do have an idea of whether it is even a valid option to ponder. So what exactly is LASIK and how does it work? Keep reading to learn more!


What is LASIK?

LASIK (“lay-sick”) is an acronym for Laser-Assisted In Situ Keratomileusis, which is the medical terminology that literally means “carving the cornea in its normal position with the help of a laser.” In simpler terms, LASIK is a type of refractive surgery that provides clear vision without the need for glasses or contact lenses. A specialized laser flattens and reshapes the cornea (the clear, front part of eye) to correct abnormalities that are involved with myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. The procedure takes roughly 20 minutes for both eyes, and an immediate improvement in vision occurs. While the vision will not be crystal clear after surgery, it will continue to improve as the eyes heal.

The ultimate desired outcome is 20/20 vision without correction, however, this may not be possible for some people. In these cases, anything better than 20/40 is a success because the individual can legally drive without glasses or contact lenses.

It is very important to understand that LASIK only corrects distance vision. This means if you are over 40 years old, you may likely still need reading glasses in the near future. Most nearsighted people have the benefit of seeing up close without any glasses. However, after LASIK surgery, a nearsighted person will no longer have this advantage if experiencing presbyopia (the need for reading glasses).


How do I know if I’m a candidate for LASIK?

There are several factors that are considered when determining if a person is a good candidate for LASIK surgery. A comprehensive eye exam and further corneal measurements are necessary for collecting all of the required information. During the comprehensive eye exam, the severity of refractive error or strength of glasses prescription gives a clue as to whether it can be corrected with LASIK. The eyes are also examined to determine if they are healthy enough for surgery. Any underlying conditions, such as dry eyes, should be treated prior to surgery since the procedure can worsen dryness. The presence of other ocular conditions, like keratoconus, would not make LASIK a suitable option.

Additional testing provides measurements of the curvature and thickness of the cornea. In order to flatten the cornea during LASIK, it must be thick enough to withstand the flattening and reshaping process. Even more information is collected with a corneal topographer, which is a digital machine that plots a topography, or map, of the cornea to identify any irregularities. Since contact lenses can temporarily change the shape of the cornea, contact lenses must not be worn for a minimum of 2 weeks prior to having a LASIK consultation. This allows the cornea to return to its normal shape before measurements are taken.

Not everyone is a good candidate for LASIK. There are other refractive surgery options available, such as PRK and phakic intraocular lens implants. If you wear glasses and haven’t worn contact lenses, it may be worth a try too!


What happens during LASIK surgery?

The LASIK surgeon begins by creating a thin flap of corneal tissue using either a microkeratome or a femtosecond laser. A microkeratome uses a blade to make the flap, whereas a femtosecond laser uses the energy of the laser to create a flap without the use of a blade. Once the flap is folded back, the surgeon uses an excimer laser to flatten the underlying cornea in a nearsighted person. In someone who is farsighted, the surgeon will steepen or build-up the cornea. Astigmatism is usually corrected during the flattening process with the laser. Once the corneal reshaping is complete, the flap is replaced and covers the area that was just altered with the laser. Sutures are not required for positioning the flap, as it is thin enough to automatically seal to the remaining corneal tissue. Don’t worry – the eye is very numb from the topical anesthetic drops, which makes this a relatively pain-free procedure.


What should I expect after LASIK surgery?

Immediately after surgery, vision should appear better, but there will likely be some haziness at first. This will improve as the eyes heal, and vision usually stabilizes over the next several days. Some people also experience burning, itching, and dryness. The LASIK surgeon will prescribe medicated eye drops to minimize the risk of infection and inflammation. Preservative free artificial tears are another crucial part of the healing process and can play a role in the long-term outcome.

It is best to rest the eyes for at least 24 hours after surgery. This means avoiding prolonged screen time, reading, and anything that strains the eyes, as it may interfere with healing. A list of restrictions or limitations will be provided for the following days and weeks after surgery. One of the most important things to remember after LASIK surgery is to avoid rubbing the eyes. This can dislodge and shift the corneal flap out of position. Other things to avoid are strenuous exercise, wearing makeup, and working in dirty or dusty environments.

Follow-up care is essential in making sure the flap has not moved, checking for signs of infection, and monitoring the improvement in vision. There should be about six follow-up appointments after LASIK surgery. The first follow-up is typically after 1 day, then 1 week, 1 month, 3 months, 6 months, and 1 year after surgery. If the final outcome has room for improvement, a very small percentage of people may receive an enhancement or touch-up procedure.


Wondering if you’re “a good candidate” for LASIK surgery? Call our office or schedule an appointment online to find out!