Last updated date: 31-May-2023

Medically Reviewed By

Interview with

Dr. Hannuy Choi

Medically reviewed by

Dr. Lavrinenko Oleg

Medically reviewed by

Dr. Hakkou Karima

Originally Written in English

Laser Vision Correction Facts - Viewpoints from Expert Doctors

    Who doesn’t dream of a beautiful pair of eyes? Some people even do some surgeries to enhance their eye appearance. 

    Besides appearance, some people dream of seeing the world clearly every day when they wake up. They wish they could open their eyes in the swimming pool and see clearly. Some people want to jog someday or play with their kids or dogs without worrying about their glasses or contact lenses. 

    Fortunately, science is always there to help improve our lives and make them easier for us. And that’s why there is now the option of laser vision correction. 

    You can totally live without eyeglasses or contact lenses forever. 


    So, have you heard about laser vision correction? Or let me say LASIK vision correction.

    You might have heard about it, or you might have a relative or a close friend who already did it. 


    Today we will talk about laser vision correction and how it can fix many vision problems. So, if you are interested, just keep on watching. 

    Before we start explaining what laser vision correction is, let’s start with some of the very common vision problems. By understanding these problems, you will understand the mechanism of laser vision correction. 


    So, let’s not waste time and begin. 


    First, I will start with nearsightedness. 

    Nearsightedness, or also called myopia, is a vision condition in which the patient can see near objects very clearly but objects far away are blurry. 


    But why does that happen? 

    It happens when the shape of the eyes refracts the rays of light or bend them incorrectly which leads to focusing the image in front of the retina and not on the retina itself. Myopia tends to run in families. It might advance gradually or rapidly. It often gets worse during childhood and adolescence.  

    Nearsightedness can cause some annoying symptoms, such as: 

    • Blurry vision when looking at a distant object. 
    • The need to partially close the eyelids to see clearly. 
    • Headaches caused by eyestrain. 
    • Difficulty seeing while driving especially at night. 

    If nearsightedness is discovered in a child and was neglected, it might lead to: 

    • Persistent squint. 
    • The need to sit closer to the TV, computer, and in front of the classroom.  
    • Blinking excessively. 

    And of course, we know the answer for how to correct it. Yes, you guessed it right. You can compensate for the blur with eyeglasses, contact lenses, and currently with laser vision correction procedures. 


    The second vision problem I am going to talk about is farsightedness.

    Farsightedness, or also called hyperopia, is a vision condition in which the patient can see distant objects clearly, but the near objects are blurry. 

    The degree of farsightedness can affect the patients’ ability to focus. 

    Farsightedness starts from birth and runs in families. 

    Symptoms of farsightedness include: 

    • Blurry nearby objects. 
    • The need to squint to see clearly. 
    • Eye Strain including burning eyes and aching around the eyes. 

    It happens when the eye is shorter than normal, or the cornea is curved too little. 

    And of course, it can be corrected by the same three options we mentioned with nearsightedness. 


    As for Astigmatism, it is a common and easily treatable condition of the eye.

    It happens due to imperfections in the curvature of the eye that causes blurred distance and near vision. 

    Astigmatism occurs if one of the two refractory structures in the eye has mismatched curves either it is the cornea, on the surface of your eyes, or it is the lens inside your eyes. Instead of having curves like a round ball, the surface has an egg shape. Consequently, the patient complains of blurred vision at all distances. 

    Astigmatism is mostly present at birth and can be combined with farsightedness or nearsightedness. 

    Symptoms of astigmatism include: 

    • Distorted vision. 
    • Eyestrain. 
    • Headache. 
    • Squinting. 
    • Difficulty seeing at night. 

    Astigmatism can be corrected by corrective lenses or surgery. 


    And now back to laser vision correction or LASIK.

    You might not know what LASIK stands for, but most probably you know what it is.

    LASIK stands for laser in situ keratomileusis. It is one of the most commonly performed and the most known laser refractive surgery.

    It is one of many corrective surgeries that work by reshaping the clear front part of your eyes known as the cornea so that when light bends, it focuses on the retina. 

    LASIK surgeries use a special type of cutting laser to precisely change the shape of the cornea and improve vision. 


    Why is it done? 

    You can speculate from the previous context that it is done when the light doesn’t focus the image on the retina as it should including cases of: 

    • Nearsightedness. 
    • Farsightedness. 
    • Astigmatism. 


    So, if you are considering LASIK surgery, you are already wearing glasses or contact lenses. But you can still wear glasses and don't undergo LASIK. 


    So, how can you know if you are a good candidate?  

    You shouldn’t have the surgery if you: 

    • Are younger than 18. 
    • Are taking certain medications. 
    • Are pregnant or breastfeeding. 
    • Have thin or uneven cornea. 
    • Have a lot of recent changes to your visual perception. 
    • Have glaucoma or dry eye. 
    • Have other health conditions like diabetes, lupus, or rheumatoid arthritis. 

    LASIK surgery has many benefits. First of all, it has been around for about 25 years now. About 96% of patients reach their vision goals after the surgery. 

    Besides, there is almost no pain, no stitches or bandages. 

    And above all, you don’t have to wear contact lenses or glasses ever again. 


    But just like any surgery, laser vision correction surgery can have some risks. Of course, complications that include loss of vision are extremely rare. But common risks of LASIK eye surgery include: 

    • Dry eyes. Sometimes the surgery causes temporary tear production. For the first six months after the surgery, the eyes may feel dry, and this might affect the quality of the vision. Therefore, doctors usually advise their patients to use eye drops for dry eyes.
    • Temporary visual problems. 
    • Glare.
    • Under Corrections. If the laser removed too little tissue from your cornea, you won’t be getting the vision results you were hoping for. It is more common for nearsighted people. 
    • Overcorrection. The laser may remove too much tissue from the eyes. It is more difficult to fix than under correction. 
    • Astigmatism. Yes, if tissue removal was off-center, astigmatism can occur. It may require additional surgery. 
    • Flap problems. Folding back or removing the flap during the surgery can cause some complications such as infections and excess tears. 
    • Regression. It happens when your vision regresses back to the original prescription. It is an uncommon risk. 

    Certain health conditions can increase the risks associated with laser vision correction surgeries, such as autoimmune disorders, weak immune system by HIV or immunosuppressant drugs, inflammation of the cornea, lid disorders, eye injuries, or eye diseases. 


    In addition to risks, you should also be aware of the side effects it may cause, including: 

    • Seeing halos around images. 
    • Trouble driving at night. After the surgery, patients report that they have trouble seeing at night which usually lasts for a few days or a few weeks. Even with good visual results of the surgery, the vision in dim light may be reduced to a great degree.
    • Fluctuating vision. 
    • Light sensitivity. 
    • Scratchy eyes. 
    • Small bruises on the eye. 


    Now it is time to talk about another technique of laser vision correction other than LASIK. It is “photorefractive keratectomy (PRK)”. 


    So, what is PRK?

    It was the first refractive surgery to be approved by the FDA. the mechanism of this surgery goes as follows: 

    • The ophthalmologist removes the outer surface layer of the cornea. 
    • Then uses a laser to reshape the cornea into a new curvature to fit the prescription of the patient’s eye. 

    This surgery might seem easier to you, but it is associated with more discomfort and a longer healing time. But for some cases, that might be their best option. 

    Doctors think that it is the best correction option for patients who need a very high correction but have a very thin cornea. 


    Another technique is called SMILE, which stands for small incision lenticule extraction. It is the newest technique for the correction of nearsightedness. It uses very precise laser beams to create disk-shaped tissue inside the cornea so that they can remove it through a small incision without a flap. 

    The good thing about this technique is that it delivers the same results as LASIK but without disturbing the cornea with flaps. Consequently, it causes less disturbance to the nerves of the cornea so it might be a good option for people who suffer from dry eye. 


    You must be confused now among all these techniques, I mean if you are considering laser vision correction surgery, which one will be good for you? 

    That depends on the very thorough examination you should have with a specialist. 


    Today we will talk about laser vision correction and how it can fix many vision problems.

    We have Doctor Choi who is a leading doctor at B & VIIT Eye Center in Seoul. She is going to discuss with us everything about laser vision correction from an experienced medical point of view. So, if you are interested, just keep on watching to learn more.



    Dr. Hannuy Choi Interview


    What is exactly laser vision correction?

    Uhm, I would say it is generally known as Lasik or Lasek surgery for the general population. Simply it makes you see the world without glasses or contact lenses as you like to be wearing them. Long ago it started with Lasik or Lasek surgeries, but now there are more options for people like Smile surgery, the recent one and topography guided surgery which enables you to get more personalized, customized and individualized surgery. 


    Perfect. In what cases will visual correction help restore vision?

    Uhm, I would say anybody who wants to take off his glasses or not wanting to wear contact lenses every day. Uhm, anybody who wants to do sports without glasses. Or anybody who wants to look pretty or handsome without glasses. Uhm, anybody can be a candidate. 


    Are there any specific indications for the surgery?

    Uhm, like medically speaking? Uhm, most important is I would say age. People over 18 are good candidates. And those who stopped like progressing myopia or astigmatism at the age of 14 but to be more safe doctors like to proceed on them after the age of 18. 


    Alright, talking about age, what is the perfect age to have laser vision correction?

    I would say if you are after age 18, the sooner the better because when you get the surgery it’s not like the surgery has an expiration date. But once you get the surgery, then you can live without glasses the longer.


    Are there any contraindications for the procedure?

    Again, medically speaking there are two contraindications for the surgery. The first one is ectasia cornea, which means like the cornea is progressively coming like front and the second one is called Avellino dystrophy which is a genetic condition. To like screen all these cases of very important like contraindications, the cases, uhm you need to get very thorough checkup before you get the surgery. 


    OK, in the case of surgery, how can the patient prepare for the laser surgery?

    So, uhm, there is not actually a very important thing you should do before you come to the hospital, but I would tell my friends or like my people who want to get the surgery, I would tell them just get a very good night's sleep before coming to the hospital. Because if you don’t sleep well, your eyes can get a little dry and the test result might not get very clear. And it can like you know to get the very good surgery results; it is very important that you have those clear test results.


    How is the surgery done. What exactly is done during the surgery?

    So, during surgery, a lot of people might be very curious about it. So, if you walk in the door there gonna be preop preparation room and there you are gonna get assistant with the nurses and other help with the eye drops that can numb your eyes during the surgery. And like to sterilize all your surgical field, which means both of your eyes, like between your eyes, and around your eyes. After getting that, you will you will see the doctor for like a very brief checkup before the surgery. And then it will probably take between ten and fifteen minutes. And after you actually lie on the surgical table, it’s only gonna take like another ten or fifteen minutes, more or less. And uhm, during the surgery I think all you are gonna remember is look at blinking lights, sometimes grid lights, a green light. Just follow the instructions as the doctor asks you to do. You are not gonna feel any pain at all. Don’t try to squeeze too hard if you’re too afraid, you can squeeze your feets too hard. Sometimes people, patients get like little bleeds in their hands, but it’s not actually the surgery itself. It’s not painful, at all. So, just keep that in mind. It’s not painful, at all. It’s gonna be like ten, fifteen minutes, more or less. After the surgery, you’re gonna go to the recovery room and get some eye drops, reduce your like discomfort and make sure that surgery went right. And then, you can go home. The whole procedure will probably take less than an hour. 


    After the surgery there is no time you should spend in the clinic, right? You can just leave?

    You can leave after like a couple of ten, fifteen minutes of recovery time.


    How about physical activity. Can you do any sports or such a thing after surgery?

    Depending on like uhm, surgeries you’ve done, you can do light sports from the next day after. Like Smile or Lasik surgery. But if you get the regular Lasek surgery, you might want to wait for at least a couple weeks to start doing the light workouts.


    Talking about female patients, they ask a lot about pregnancy, and if they should wait after the surgery to get pregnant or if they should get pregnant before the surgery. What do you think about it?

    If you’re not pregnant at the points that when you ‘re getting the surgery, uhm, before or after the surgery it’s not very important factor to decide to get the surgery. At this point, if you ‘re pregnant, I wouldn’t recommend that you get it like surgery. Before the pregnancy or after the pregnancy is not that important. 


    OK. When we talk about laser vision correction, there are many words that come out – like Smile, Lasik, Lasek, what is it exactly the difference between them?

    Oh, it’s to make sure that you understand all that, it’s gonna probably take more than like hour to two hours, so let me explain to you like I explain my patients in an easy and simple way. There are like two categories that you should keep in mind when you decide what kind of surgery you want to get. So, the first one is uhm, about the safety of the surgery. So, among the three surgeries, uhm I would say if you want a very safe and stable surgery, then you might want to get Smile or Lasek surgery with “E”. And the second category that you should keep in mind is how much recovery time you can spend after the surgery. So, uhm if you have to go back to everyday life right after the surgery, you might want to get the Lasik surgery with a “I” or Smile surgery. Like Lasek surgery with a “E’ can be pretty painful for the first couple days. Take quite a long time to get full recovery of the vision, so it’s gonna be at least a month or two. So, you need to think about it before the surgery. Uhm, Smile Lasik is the most recent technology-wise based and added feature lacked in Lasik surgery. Lasik surgery is said to be very convenient in terms of fast recovery and painless surgery. But the only problem with the Lasik surgery is that it makes a flap on the cornea that can damage the safety and ability of the cornea. When you get the Smile surgery, the size of the incision is less than one quarter of the Lasik flap incision. And this is how the Smile surgery can provide higher stability and safety of the cornea after surgery. So, it sounds like Smile surgery is the best of all kinds but it is just generally speaking. That said, with certain eyes Smile surgery is not suitable. For example, like eyes with high astigmatism and hyperopia and some cornea with asymmetric cornea shape. Those are not suitable for the Smile surgery. So, knowing all these pros and cons, you can choose a certain surgery that is most suitable for you and the clinic will give you the option that you can choose. Also, provide the what kind of surgery is the best fit for you.


    Surgery depends on the patient, right?



    What are the side effects of laser vision correction?

    Laser vision correction. Yeah, so there are always as I said pros and cons when you get the medical procedure or the surgery. Most common complaints after surgery is dry eye and the glare. If you get any eye surgery between Lasik surgery Lasek surgery or like glaucoma surgery, cataract surgery, any kind of eye surgeries, you will have a dry eye for like six months to one year. 


    It’s a long time.

    Yeah, so during this period I recommend using artificial tears even though you don’t feel the dry eye. And same with the glare, will go away step by step as time goes mostly within a year. 



    Laser vision correction allows people to see the world without glasses or lens contact.  While many people are aware of Lasik, now there are advancements to the technology such as Smile surgery. 

    While there are a few exceptions, anyone 18 and over who wishes to take off his glasses or lens contact, do sports or simply wants to improve his look is able to get laser vision correction.

    There are several techniques in laser vision correction. Lasik, Lasek and Smile are three of the most popular laser methods to achieve vision correction. Lasik has the benefit of being pain-free and a quick recovery period. Smile improves upon the benefits of Lasik by only leaving a tiny flap in the cornea compared to Lasik, increasing stability and safety. Lasek is ideal for people with thin corneas. The disadvantages are that it is a painful procedure and the recovery time is much longer than Lasik or Smile. The advantage is that no flap is created, limiting the possibility of scarring of the cornea.

    It is important to get a good night's sleep prior to the day of surgery as exhaustion or tiredness can dry the eyes and the diagnostics test results can become less accurate.  

    The laser vision correction surgeries take less than an hour to complete. Except for Lasek, the procedures offer the convenience of very quick recovery – you can go back to normal life right afterwards. 

    It is normal to have dry eyes after the surgery. It is recommended to use artificial tears to remedy the condition for six months or more, as needed.