What Is LASIK Eye Surgery? Benefits, Risks And Side Effects

LASIK eye surgery is a corrective vision laser surgery typically performed by ophthalmologists (eye surgeons) on patients who otherwise have healthy eyes but don’t want to wear glasses or contact lenses.

LASIK surgery candidates usually have moderate degrees of refractive error, including nearsightedness, farsightedness, astigmatism or presbyopia (the inability to focus on objects up close as a result of aging). Additional requirements often include a stable prescription, age older than 18, not being pregnant, corneas that are not too thin and eyes free of injury or disease.

“LASIK surgery is performed on the front layer of the eye using the laser to reshape the cornea—where most of the focusing power of the eye lives,” says Neda Shamie, M.D., a LASIK, cataract and corneal surgeon at the Maloney-Shamie Vision Institute in Los Angeles. LASIK can safely and precisely correct nearsightedness and astigmatism and lower levels of farsightedness, she adds.

The journey toward vision correction with LASIK begins with a consultation with a refractive surgeon, explains Dr. Shamie. During this initial meeting, which may be done virtually, the doctor can determine whether the patient is a good candidate for the procedure. A formal in-office consultation generally follows, which is when a LASIK evaluation occurs. It involves measuring the eye in preparation for the surgery, as well as extensive precise diagnostic testing.

A doctor will measure eye dryness and contrast sensitivity, and evaluate pupil size, corneal thickness, shape and topography, as well as look for higher-order aberrations—a specific type of distortion within the eye structure—that may negatively impact vision, according to the American Academy of Ophthalmology.

On the day of the surgery, the patient is given a mild sedative to relieve anxiety about undergoing the surgery. The procedure itself is “painless and quick,” says Dr. Shamie, lasting no more than 10 minutes for both eyes. “During the procedure, you are awake but very comfortable,” she adds.

In the procedure, the surgeon first creates a LASIK flap in the frontal, topmost layer of the cornea (the epithelium) using a laser. “During this step, the patient may feel a slight pressure on the eye,” says Dr. Shamie. The flap enables the doctor to reshape and contour the cornea using a second laser.

“Immediately after the surgery, the person usually sees better without glasses than they ever have,” says Vicente Diaz, M.D, an ophthalmologist and assistant professor of ophthalmology and visual sciences at Yale School of Medicine in New Haven, Connecticut. In terms of post-op recovery, you should consider taking a few days off work, as you might experience burning, itching, mild pain or discomfort in your eyes. Your vision may be blurry, but will continue to improve each day over the first week, leveling off in two to three months.

How Long Does LASIK Last?

Dr. Diaz notes that the effects of surgery on distance vision are permanent for the majority of people. “In eyes with high refractive error—meaning more severe cases of nearsightedness, farsightedness or astigmatism—there can be some regression over a period of years, though the vision rarely gets as bad as before surgery,” he says.

While LASIK is effective in improving vision for those who are nearsighted, Dr. Diaz points out that it does not prevent presbyopia, which is the age-related need for reading glasses. “Patients should be aware that even though the distance vision will be good, they may still need glasses for up-close vision.”

Does LASIK Hurt?

Dr. Shamie says LASIK is relatively painless, though “slight pressure” might be experienced at some points during the 10-minute procedure.

The average cost of LASIK depends on the expertise of the surgeon and the advanced laser technology used, says Dr. Shamie. At Maloney-Shamie Vision Institute, the cost can range from $1,000 an eye to $3,500 an eye, typically with no other costs related to the procedure. While the postoperative follow-up is generally included in the cost, how long the coverage lasts may differ.

Health insurance typically doesn’t cover the cost of surgery, but health savings accounts (HSAs) and flexible spending accounts (FSAs) can be used for LASIK.

Dr. Diaz warns not to bargain shop when it comes to LASIK. “Be wary of places that are charging only a couple of hundred dollars—this may be a tactic to get you in the door, but the service offered in this price range may not be the best option,” he says.

Most individuals who are dependent on glasses or contacts to see well are candidates for LASIK, says Dr. Shamie. “The age [range] during which LASIK is an excellent option with lasting effects is when the prescription has stabilized but the aging of the eye hasn’t yet started, which typically is between age 21 and one’s early 40s,” she says.

LASIK can correct nearsightedness, farsightedness and astigmatism, with the degree of correction differing for each category.

Nearsightedness

LASIK improves the focusing power of a nearsighted eye—an eye that doesn’t see well at a distance—by reshaping the center of the front surface of the cornea and flattening it, says Dr. Shamie. However, there is a limit as to how much a cornea can be flattened, which is why the surgery isn’t recommended for those who need major vision correction.

Farsightedness

Farsightedness—eyesight that struggles with closer objects—is treated by reshaping the cornea so that the center becomes steeper. “Because there is a limit as to how much steepening can be done before vision quality deteriorates, we limit the amount of farsightedness that can be corrected well with LASIK and, for higher corrections, offer a different surgical option,” she explains.

Astigmatism

Astigmatism—a condition defined by blurry vision or an unevenly curved or flattened cornea that can accompany either nearsightedness or farsightedness—can also be treated with LASIK “within the limit,” says Dr. Shamie. LASIK can correct this issue by smoothing the odd-shaped curve to make it more evenly round.

Who Isn’t a Good Candidate for LASIK?

Some eye conditions, such as glaucoma or diabetic retinal disease, are considered relative contraindications to LASIK (meaning there could be complications as a result) as are rare conditions of the front layer of the eye, including corneal dystrophies. Any of these conditions could pose added risk to the surgery, says Dr. Shamie.

There’s an array of benefits associated with LASIK, including:

Improved Vision

Both Dr. Shamie and Dr. Diaz note the main benefit of LASIK is an indefinite improvement to eyesight. In fact, one study in JAMA Ophthalmology reported more than 95% of patients were satisfied with their vision following LASIK surgery^[2]Eydelman M, Hilmantel G, Tarver ME, et al. Symptoms and Satisfaction of Patients in the Patient-Reported Outcomes With Laser In Situ Keratomileusis (PROWL) Studies. JAMA Ophthalmol. 2017;135(1):13–22. .

It Might Save You Money

While the cost of contact lenses and glasses varies significantly, without insurance they can easily cost up to $500 per year. Therefore, it’s likely that you will recoup the cost of LASIK surgery within a few years.

You Might Avoid Eye Infections

A 2016 study in Ophthalmology found LASIK significantly reduced self-reported rates of eye infections, ulcers and abrasions annually compared to the self-reported rates of people who wear contact lenses continuously^[3]Price MO, Price DA, Bucci FA Jr., Durrie DS, Bond WI, Price FW Jr. Three-Year Longitudinal Survey Comparing Visual Satisfaction with LASIK and Contact Lenses. Ophthalmology. 2016;123(8):1659-1666. .

LASIK is safe most of the time. “It is crucial to do adequate testing before surgery to select appropriate candidates,” says Dr. Diaz. In those patients, LASIK is one of the most successful surgeries in all of medicine, he says, citing more than 90% of patients end up with 20/20 vision or better.

For most patients, recovery is quick with very few side effects. “There can be some irritation the first day or two after surgery—a feeling like there is soap in your eyes,” says Dr. Diaz. Fortunately, doctors can prescribe medications to help.

However, according to research in JAMA Ophthalmology, while the majority of participants were satisfied with their vision following LASIK surgery, a few (less than 1%) of LASIK patients experienced side effects after surgery that impacted their ability to perform their usual activities such as night driving^[4]Eydelman M, Hilmantel G, Tarver ME, et al. Symptoms and Satisfaction of Patients in the Patient-Reported Outcomes With Laser In Situ Keratomileusis (PROWL) Studies. JAMA Ophthalmol. 2017;135(1):13–22. . They also reported debilitating vision symptoms (seeing starbursts, glare, ghosting or halos) and severe dry eye. Per the study, which assessed patients at the time of surgery, three and six months post-op, side effects lessened over time.

Meanwhile, the study found 46% of all participants (who also reported no visual symptoms prior to surgery) experienced at least one visual symptom—most commonly halos—three months following the operation. In fact, up to 40% of participants with no halos before LASIK had halos three months following surgery. Additionally, of those with no dry eye symptoms prior to LASIK, 38% reported developing them three months after surgery.

According to Dr. Diaz, other risks include bleeding, infection and inflammation. “With LASIK some of the most important risks include haze in the cornea and not healing correctly, [which is] called ectasia,” he says.

Dr. Shamie also says a side effect for patients who require extensive reshaping may be nighttime glare due to the amount of reshaping needed, which is why many doctors avoid pushing the limits of safety with corneal-based procedures.

In addition to LASIK, photorefractive keratectomy, or PRK, is another common corrective vision surgery. “LASIK and PRK are similar in that they are both surgeries intended to change the shape of the cornea in order to eliminate the need for glasses and contact lenses,” says Dr. Diaz.

The main difference between the two is that in LASIK surgery, the superficial layers—the flap—are moved out of the way temporarily, and in PRK, they are not. “Instead, in PRK, the very most superficial layer—the corneal epithelium—is completely removed and allowed to grow back after the surgery,” he explains.

There can be safety benefits to PRK over LASIK. For instance, by not creating a flap, complications can be eliminated. “Also, patients with thinner corneas (for whom creating a flap is not as safe) would be eligible for PRK but not LASIK,” says Dr. Diaz.

In terms of recovery, both vision and comfort improve more quickly with LASIK than PRK. But as for effectiveness, “in the end, both techniques are comparable in terms of final vision obtained,” says Dr. Diaz.

Dr. Shamie affirms that nearly all of her patients are happy with the results. “The freedom it offers patients to be able to get up and go without being burdened by the need for glasses and contacts is energizing,” she says. “LASIK patients often speak of the impact LASIK has on the way they travel without the need to worry about contact solutions and fear of losing their glasses. They comment on how much more active they are, not thinking twice anymore about the fear of losing their contacts while swimming in the ocean or going for a bike ride.”

Ultimately, deciding to get LASIK is a personal choice. “With every surgery, we balance risk and benefit,” says Dr. Diaz. “The benefit, in this case, is improvement of life with spectacle independence. If that happiness is important to the patient and exceeds their fear of complications and desire to keep their money, then they may decide it’s worth it.”