Potential Complications of SMILE Surgery

 

1. Considering Vision Correction Surgery?

Glasses and contact lenses are undoubtedly useful tools for compensating for poor vision. However, the inconveniences they bring to daily life can be greater than one might expect. Glasses that slip down your nose due to sweat during exercise, contact lenses that must be carefully disinfected and worn before going out, and the discomfort or eye fatigue caused by long hours of lens wear — these are experiences most people have encountered at least once.

Despite this, many hesitate to undergo vision correction surgery, largely due to concerns about potential side effects. But are these side effects truly as serious and burdensome as we often imagine? The short answer is that the vast majority of side effects from vision correction procedures are temporary and can be effectively managed. In particular, SMILE surgery — which has been gaining attention in recent years — is known for its faster recovery and significantly lower incidence of side effects compared to conventional procedures, earning positive feedback from many patients.

▲ Extent of Corneal Epithelial Damage by Type of Vision Correction Surgery

2. Where Do Side Effects from Vision Correction Surgery Originate?

All medical procedures carry some degree of risk for side effects, and vision correction surgery is no exception. Commonly reported symptoms include pain, dry eyes, and glare or halos. These symptoms typically appear immediately after surgery and gradually subside or disappear over time.

But why do such side effects occur? The primary reason lies in the extent of damage to the corneal epithelium. The corneal epithelium is a crucial structure that protects the eye and plays a role in tear production. If a large portion of this layer is removed during the procedure, the eye’s function may temporarily decrease, leading to symptoms such as pain or dryness.

In LASIK and LASEK, the surgery physically cuts or removes the corneal epithelium, which is why recovery time is required and the likelihood of side effects is relatively higher compared to other methods.

▲ Femtosecond laser technology that passes through the corneal epithelium without causing damage (right)

3. SMILE Technology That Preserves the Corneal Epithelium

SMILE surgery differs significantly from conventional methods, with its most notable feature being the preservation of the corneal epithelium. Using a specialized femtosecond laser, SMILE creates a thin, lens-shaped piece of tissue called a lenticule within the corneal stroma. This lenticule is then removed through a micro-incision of less than 2 mm.

Because this process does not involve extensive removal of the corneal epithelium, it minimizes damage to tear-producing cells and corneal nerves, thereby reducing the risk of side effects. As a result, the incidence of dry eye is lowered, and both post-operative discomfort and recovery time are dramatically reduced. In fact, many patients are able to return to work and daily activities without discomfort as early as the day after surgery. These clinical outcomes serve as strong evidence supporting the safety and reliability of SMILE surgery.

▲ Goblet cells help maintain tear production and healthy eye function — when they are reduced, dry eye symptoms may occur.

4. Proven Technology — Global Figures that Speak for Themselves

SMILE surgery was developed by ZEISS, a German optical equipment company, and has now been performed in more than 8 million cases worldwide, including over 1.3 million cumulative procedures in Korea. These figures are not merely the result of marketing, but the outcome of trust built between medical professionals and patients alike.

SMILE has received official approval from the U.S. Food and Drug Administration (FDA) and is also the procedure of choice for the U.S. military to improve soldiers’ vision — a testament to its recognized stability even under extreme conditions. This demonstrates that SMILE is not only a surgery with a low incidence of side effects but also a highly precise and safe vision correction method.

When considering vision correction surgery, side effects are often the first concern that comes to mind. The best way to overcome this fear is through understanding based on accurate information. SMILE, with its advanced technology that overcomes the limitations of conventional methods, can reduce side effects while delivering excellent visual recovery.

If you are feeling restricted in daily life due to the inconvenience of corrective devices, we recommend that instead of worrying, you undergo an accurate diagnosis and thorough consultation to find the vision correction procedure most suitable for your eyes. Side effects are not necessarily unavoidable dangers; they are often temporary changes that can be managed and addressed within a safe range.

As mentioned earlier, not all SMILE surgeries are the same. Only procedures performed with ZEISS VisuMax equipment are considered the verified SMILE technology. Keep this in mind when choosing a medical institution. The combination of accurate information and a trustworthy medical team is the safest first step toward a healthier, clearer vision.