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Laser surgeries to correct refractive errors are relatively new. Since LASIK was approved by the Food and Drug Administration (FDA), related operations have become popular ways to improve visual clarity for nearsightedness, farsightedness, or astigmatism.
LASIK is one of the first laser-guided operations to reshape the cornea, and this procedure works for all types of refractive errors. SMILE is a newer version with fewer side effects. It is even less invasive than LASIK, but it only works for people with myopia and, sometimes, associated astigmatism.
While there are some important differences between SMILE and LASIK, the pros and cons of both overlap a lot. They are roughly the same cost, have similar healing times, have similar side effects, and correct refractive errors within about the same range, typically to 20/40 or better.
You may be a better candidate for SMILE than LASIK, however. Work with your eye doctor to decide which procedure works best for your eyes.
Laser Surgeries for Refractive Errors: SMILE Eye Surgery vs. LASIK
Refractive errors are the most common forms of vision problems. These involve issues with the shape of the cornea, which make it difficult to see clearly at certain distances. Myopia, or nearsightedness, is the most common form of refractive error. Astigmatism, presbyopia (age-related farsightedness), and hyperopia (farsightedness) are also quite common.
For centuries, glasses have been the best way to correct blurry or double vision. Then, contact lenses became the leading way to see clearly, without many people knowing you have a refractive error. Despite their benefits, contact lenses can be uncomfortable, require maintenance, and still do not correct vision on a long-term basis.
Thanks to advancements in laser-guided surgeries, starting with LASIK, millions of people around the world have clear vision without glasses or contact lenses. LASIK is the most famous and popular of these surgeries, improving most refractive errors to 20/40 clarity or better.
While LASIK works for many people, it is not a perfect solution for some. As a result, more forms of laser vision correction have been developed, like the SMILE procedure. If you are looking for laser eye surgery to correct your refractive error, it is important to know the differences between these options so you can discuss them with your ophthalmologist.
SMILE vs. LASIK: What Are the Similarities & Differences?
Laser surgeries to improve refractive errors have evolved since the 1980s.
Originally, these procedures involved very small scalpels to make incisions and reshape the cornea or lens; however, most modern versions involve programmed lasers for much of the procedure. This reduces the time in the operating room, reduces the invasiveness, and improves surgical accuracy and healing time. It also reduces cost.
- LASIK basics: This acronym stands for laser-assisted in situ keratomileusis. During the procedure, a laser removes tissue from the cornea, so it can reshape and refract light correctly to the retina, at the back of your eye.
The procedure takes about 15 minutes per eye, and local anesthesia is used. You remain awake during the procedure. Healing takes a day or two. Most people return to work the next day, although you should avoid activities like moderate to intense exercise, especially swimming, for a few weeks.
During the LASIK procedure, your eye surgeon will use a device to make a small flap in your cornea. They will either use a microkeratome (a miniscule, machine-guided scalpel) or a specialized femtosecond laser. Then, they will remove some corneal tissue to reshape the cornea, using an excimer laser.
The amount and location of removed corneal tissue depends on the type of refractive error you have, but LASIK can correct all types of refractive errors, including combined refractive errors. For example, astigmatism can occur alongside either farsightedness or nearsightedness.
- SMILE basics: This acronym stands for small incision lenticule extraction (SMILE). It is a newer type of laser refractive eye surgery based on LASIK. Although this procedure has been used worldwide for over 10 years, the FDA approved the process and associated devices for the U.S. market in 2016. SMILE specifically treats nearsightedness, or myopia. It is considered less invasive than LASIK because it does not require creating a flap in the cornea to reshape it.
The setup for SMILE surgery is like LASIK in many ways. You receive numbing eye drops, the laser is preprogrammed with a map of your cornea, and you lie or sit down for about 15 minutes per eye while the laser reshapes your cornea. The healing time is about the same, but there is less risk of scarring on the cornea or the corneal flap detaching from your eye. You will also not be moved from one device to another, because there is only one laser involved, so you have a lower risk of dry eye as a side effect. SMILE is a good option for people with myopia who are not good LASIK candidates.
Similarities Between LASIK & SMILE
There are many similarities between LASIK and SMILE. The SMILE procedure was developed from LASIK, since that type of laser eye surgery was so popular.
They both take about 10 to 15 minutes. They both require only a day of rest and healing. They both cost between $2,000 and $3,000 on average.
The steps of the procedures are similar.
- You’ll work with an ophthalmologist or optometrist to determine which laser procedure is the best to correct your refractive error.
- They will make a map of your cornea to program into the laser.
- The doctor will reshape the cornea using a guided laser.
- You will rest your eyes at home for about one day following either procedure.
- Avoid putting anything in or near your eyes, like contact lenses or makeup, for a week or two after the surgery.
- You’ll use antibiotic eye drops to prevent infection.
- There is the potential for similar side effects for up to six months, like glares or halos around lights, dry eye, and a little trouble with vision in low-light situations.
- Both procedures lead to at least 20/40 vision for most patients and 20/20 vision in many. The long-term results are consistent and predictable.
- Both procedures have similar qualifications for patients, like:
- You must be at least 21 years old.
- You must have otherwise healthy eyes.
- You must not have underlying conditions that impact your ability to heal, like autoimmune conditions or diabetes.
- You must not be pregnant or breastfeeding.
Differences Between LASIK & SMILE
While both SMILE and LASIK are procedures that use lasers to reshape the cornea and improve visual acuity, there are several differences between the two that can help you determine if one might work better for your eyes.
Here are some of the major differences in SMILE vs. LASIK:
- LASIK treats all refractive errors. SMILE treats myopia with or without astigmatism, but not farsightedness or astigmatism by itself.
- LASIK requires a flap to be cut in the cornea, so the excimer laser reaches the inside of this part of your eye. SMILE reshapes the top of the cornea to flatten it.
- LASIK is not a good choice for people who have thin corneas. SMILE can still benefit nearsighted people who have thin corneas.
- LASIK has better recovery from side effects at a seven-day follow-up point compared to SMILE, although there was no difference in recovery rates at one month after the operation.
- LASIK patients report slightly lower satisfaction with their procedure compared to people who chose SMILE, but both procedures have high patient satisfaction long term. Ultimately, most people who get either procedure are happy with the results.
- LASIK, and other types of refractive surgery like photorefractive keratectomy (PRK), can treat higher-order aberrations (HOAs) that impact night vision, while SMILE cannot treat these issues.
- LASIK is a less demanding procedure for eye surgeons, while SMILE is newer and requires more intensive training. Fewer surgeons specialize in SMILE.
- LASIK has been around for about 20 years, and there are few new developments with the procedure. SMILE is new to the U.S. and there are exciting developments, according to eye surgeons.
Similar Pros & Cons
There are several pros and cons to both SMILE and LASIK eye surgeries, and many of the benefits and detriments overlap. For example, both procedures are quick outpatient procedures. Both are safe with minimal risk of side effects and a high rate of success in clinical studies. The healing time for both is also very short, so most patients experience improved vision in just a few days.
Similarly, side effects for both LASIK and SMILE can last for up to six months. Although they are rarely serious, halos or glares, dry eye, and light sensitivity can be uncomfortable.
Both procedures typically correct refractive errors, so patients have visual acuity of around 20/40 or better. There is a risk of either undercorrection or overcorrection, which requires further eye surgeries that are more invasive. With both procedures, there is a minimal risk of infection, worsened eyesight, and other side effects, though these are very rare.
If you have a changing refractive error, you may need to undergo either LASIK or SMILE again. Unfortunately, if you undergo either procedure once, you may not be a good candidate for it a second time, as your corneas may be too thin.
Which Is Better: SMILE or LASIK?
Ultimately, both SMILE and LASIK are affordable procedures to improve refractive errors, with certain limitations on who is a good candidate for each option. There are fewer side effects with SMILE, mostly related to the lack of flap creation, but the healing time is a little longer than with LASIK.
SMILE only works for people with myopia. In some cases, it can be effective for those with a mild, associated astigmatism. If you have myopia and thin corneas, SMILE can be a great option for you.
Results from both SMILE and LASIK are very similar. Patients who receive each procedure report high rates of satisfaction and long-term vision correction.
With both SMILE and LASIK, it’s very important to follow your doctor’s postoperative care instructions. This ensures an optimal healing process with the lowest risk of complications. Both procedures have very low rates of complications, with LASIK being considered one of the safest surgical procedures in existence.
Many more surgeons specialize in LASIK, simply because it has been around for longer, and it is a more in-demand procedure. More ophthalmologists are receiving training to perform the SMILE operation, however.
Talk with your eye doctor to determine the best procedure for you. For most people, LASIK will be the recommended choice. For people who aren’t good candidates for LASIK, SMILE may be a viable option.
Future of SMILE and LASIK Eye Procedures
LASIK and SMILE procedures are considered top-of-the-line eye treatment options. With the advancement of technology and more studies documenting success rates and short- and long-term side effects, not to mention results of ongoing clinical trials, these procedures should only prove more successful over time.
There is still room for advancement because these procedures do not cater to some eye conditions. For instance, SMILE is not suited for people with extreme cases of myopia, and LASIK does not always work well for patients with compound hyperopic astigmatism.
Researchers and surgeons need more data to judge the effectiveness and predictability of SMILE procedures. Institutions like the Taijin Eye Hospital and the University Medical Center Shanghai of China are carrying out studies to improve SMILE procedures. The hope is that results will help streamline and standardize both LASIK and SMILE surgeries.
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