What Is the Difference Between SMILE and LASIK Eye Surgery?

If you’re thinking about laser eye surgery for vision correction, you may be able to choose between SMILE and LASIK. While LASIK is a well-known laser procedure that has been used for several decades, SMILE is a newer approach.

Both surgical procedures improve visual acuity by reshaping the cornea (the clear tissue covering your eye). Comparative studies show that LASIK and SMILE are both safe and effective surgeries with excellent outcomes.¹

However, LASIK and SMILE surgery differ in key ways, including:

• Surgical technique
• Visual recovery time
• Potential side effects and complications
• Types of refractive errors treated

It’s important to discuss your options with an eye surgeon before choosing the type of eye surgery that’s right for you. This article covers the differences between SMILE and LASIK to help you make an informed decision.

Similarities Between LASIK and SMILE

LASIK and SMILE share many of the same benefits, including:

• Low risk. Both procedures are very safe and effective.
• Minimal downtime. The downtime for both procedures is minimal. Patients can return to their daily activities, including exercise, within a few days.
• Quick and relatively painless. SMILE and LASIK patients can return home the same day as the procedures.
• Similar effectiveness. Most people will have 20/20 vision within one month.
• Similar cost. In the U.S., the average cost of SMILE and LASIK eye surgery is between $1,800 and $3,600 per eye.

Differences Between LASIK & SMILE Eye Surgery

LASIK and SMILE are similar vision correction procedures and provide the same results (20/20 vision). The main difference is that SMILE doesn’t use an excimer laser to remove corneal tissue. 

Other notable differences include:

What Is SMILE?

Small incision lenticule extraction (SMILE), sometimes called ReLex SMILE, is a new type of laser eye surgery approved in 2016. 

Unlike LASIK, which can treat a variety of refractive errors, SMILE only corrects myopia (nearsightedness) and myopic astigmatism. If you wear glasses or contact lenses for blurry distance vision, SMILE may be an alternative.

SMILE Procedure

SMILE surgery is less invasive than LASIK. The SMILE procedure uses a smaller incision and doesn’t involve cutting a corneal flap.

During SMILE surgery:

1. Your eye surgeon uses a femtosecond laser to create a disc-shaped layer of tissue (lenticule) below your corneal surface. This takes approximately 30 seconds.
2. The laser cuts a tiny opening (2 to 4 mm) in your cornea.
3. The eye surgeon removes the lenticule through the opening, reshaping your cornea.

What is LASIK?

Laser-assisted in situ keratomileusis (LASIK) is a popular laser vision correction procedure with a well-established success rate. LASIK has been used for more than 30 years to correct different refractive errors, including:

• Myopia (nearsightedness)
• Hyperopia (farsightedness)

Astigmatism (blurry vision caused by irregular cornea shape)

LASIK Procedure

When performing a LASIK procedure, a refractive surgeon will either use a traditional or bladeless technique. We consider both procedures extremely safe and effective.

• Traditional LASIK. This approach involves using a surgical blade (microkeratome) to cut a flap in your corneal tissue.
• Bladeless LASIK. This surgical technique uses a femtosecond laser instead of a surgical blade. 

While SMILE is a one-step procedure that uses one laser, LASIK involves two steps and uses either two lasers or a laser and a blade. 

During LASIK:

1. Your eye surgeon uses a microkeratome or a laser to cut a small flap in your cornea. They fold back the flap to expose the tissue beneath your corneal surface.
2. The surgeon uses a different type of laser (excimer laser) to remove some corneal tissue and reshape it.
3. The flap is replaced. You may receive a bandage contact lens to protect your cornea while it heals.

LASIK vs. SMILE Eye Surgery

LASIK and SMILE are effective and safe refractive surgeries that produce excellent visual outcomes. However, these different approaches to laser eye surgery stand apart in key areas:

Surgical Technique

SMILE is a simpler and less-invasive surgical procedure than LASIK. There are several reasons for this, including:

• Corneal flap. LASIK requires cutting a flap in the cornea, and SMILE doesn’t.
• Incision size. SMILE uses a small incision (2 to 4mm), while LASIK creates a 24mm flap.
• Tissue damage. SMILE surgery damages fewer corneal nerves than LASIK.

Visual Recovery Time

SMILE and LASIK have high success rates for long-term visual outcomes. However, SMILE can take more time to recover from.

Clinical studies show that people who got LASIK experienced better visual acuity and fewer visual symptoms in the first week than people who got SMILE. After one month, there was no difference in visual outcomes between the two groups.² 

Risks and Side Effects

One of the main advantages of SMILE is that it involves fewer risks and side effects. This is because SMILE is a less invasive procedure. 

Corneal Flap Complications

LASIK uses a corneal flap incision, which involves the risk of flap-related complications. The flap usually heals without problems, but it can shift or move. This is especially true in cases of eye trauma. Athletes and people at risk of eye trauma may prefer SMILE.

Dry Eye

LASIK involves a greater risk of dry eye than SMILE. The smaller incision in the SMILE procedure minimizes corneal nerve damage, making dry eye less likely. 

Refractive Errors Treated

SMILE is currently only available for people with myopia (nearsightedness) and myopic astigmatism.

People with hyperopia (farsightedness) may want to consider LASIK or other types of laser eye surgery, such as PRK.

How to Choose the Right Laser Eye Surgery for You

SMILE and LASIK are comparable in terms of safety, cost, and visual outcomes. To determine the best type of laser eye surgery for you, consider the following:

• Refractive error. If you have hyperopia (farsightedness), you’re not a candidate for SMILE.
• Lifestyle. People who play contact sports or have active lifestyles may benefit from SMILE’s lower risk of complications. 
• Recovery time. LASIK may be the better option if you need clear visual acuity less than one week after surgery.

As with any laser eye surgery, discussing your concerns with an ophthalmologist is important. They’ll review the benefits and disadvantages of each procedure and recommend the best option for you.

Other Types of Eye Surgery

If neither SMILE nor LASIK appeals to you, your eye doctor may recommend one of the following refractive surgeries:

PRK

Like LASIK, photorefractive keratectomy (PRK) uses an excimer laser to reshape your cornea. But instead of cutting a corneal flap, this procedure removes the outer layer of corneal tissue (epithelium).

LASEK

Laser-assisted subepithelial keratectomy (LASEK) is similar to PRK and LASIK. Instead of removing the epithelium or cutting a flap, this procedure loosens the corneal epithelium with an alcohol solution.

Summary

• SMILE and LASIK are two highly successful laser eye surgeries.
• Both SMILE and LASIK are extremely safe, but LASIK has a slightly higher risk of complications.
• SMILE can only treat myopia (nearsightedness) and myopic astigmatism.
• LASIK treats several refractive errors, including hyperopia (farsightedness)
• The main difference between LASIK and SMILE is that LASIK involves creating a flap in the corneal tissue.
• Because SMILE doesn’t require a flap, there’s less risk of dry eye and flap complications.