LASIK, Laser and Refractive Eye Surgery
Vision correction surgery, also called refractive and laser eye surgery, refers to any surgical procedure used to fix vision problems. Recent years have seen huge advances in this field. Refractive and laser eye surgery allow many patients to see better than any other time in their lives.
Most types of vision correction surgery reshape your cornea, the clear front part of your eye. That lets light travel through it and focus properly on the back of your eye, or retina. Other procedures replace your eye’s natural lens.
What Is LASIK Eye Surgery?
LASIK, which stands for laser in-situ keratomileusis, is a popular surgery that can correct vision in people who are nearsighted or farsighted, or who have astigmatism.
It’s one of many vision correction surgeries that work by reshaping your cornea, the clear front part of your eye, so that light focuses on the retina in the back of your eye.
Why Is LASIK Done?
When light doesn’t focus on your retina the way it should, your vision is blurry. Doctors call this a refractive error. The basic types include:
- Nearsightedness (myopia). You see things clearly when they’re close to you, but things farther away are blurry.
- Farsightedness (hyperopia). You see faraway things more clearly, but closer things are blurry.
- Astigmatism. This can make everything blurry because of how your eye is shaped.
Talk to your doctor about whether LASIK is right for you. You shouldn’t have the surgery if you:
- Are younger than 18
- Are pregnant or nursing
- Take certain medications
- Have a lot of recent changes to your vision prescription
- Have thin or uneven corneas
- Have eye conditions such as glaucoma or very dry eyes
- Have other health issues such as diabetes, lupus, or rheumatoid arthritis
LASIK Eye Surgery Benefits
The benefits of LASIK include:
- It’s been around for over 25 years. About 96% of patients reach their vision goals afterward. An enhancement can raise this number even more.
- There’s very little, if any, pain involved.
- There aren’t any bandages or stitches.
- If your vision changes as you age, your doctor can adjust it.
- You probably won’t need to use glasses or contacts as much, or at all, after LASIK.
LASIK Eye Surgery Risks
As with any surgery, LASIK carries some risks, including:
- It’s a complex procedure. It’s rare, but there may be problems that permanently affect your vision. This is one reason to choose a surgeon who has a lot of experience with these surgeries.
- Rarely, you may lose your “best” correctable vision, the highest degree of vision that you had while wearing contacts or eyeglasses, after LASIK.
- Most insurance doesn’t cover LASIK.
LASIK Eye Surgery Side Effects
Some patients have discomfort in the first day or two after LASIK eye surgery. Other side effects are rare and usually go away over time. They include:
- Seeing halos around images
- Trouble driving at night
- Fluctuating vision
- Dry eyes
- Scratchy eyes
- Light sensitivity
- Small bruises on your eye
How Should I Prepare for LASIK Eye Surgery?
Before LASIK, you’ll meet with a coordinator or eye surgeon who will talk about what to expect during and after the procedure. They’ll ask about your medical history and do a full eye exam. This may include tests to measure the thickness of your cornea, refraction, and eye pressure. They may map your corneas and dilate your pupils. The surgeon will answer any questions you may have. Then, you can schedule an appointment for the surgery.
If you use rigid gas-permeable contact lenses, don’t wear them for at least 3 weeks before your evaluation. Don’t wear other types of contact lenses for at least 3 days prior to the evaluation. Be sure to bring your eyeglasses so the surgeon can review your prescription.
On the day of your surgery, eat a light meal before going in, and take all of your prescribed medications. Don’t wear eye makeup or bulky accessories in your hair that might interfere with your head position. If you’re not feeling well that morning, call the doctor’s office to ask what you should do.
What Happens During LASIK Eye Surgery?
Your doctor will give you drops to numb your eyes. You can also ask for a mild sedative.
They’ll use an instrument called a microkeratome or a femtosecond laser to make a thin flap in your cornea. They’ll peel it back and use another laser to reshape the tissue underneath. Then, they’ll put the flap back in place, and the surgery is done.
The LASIK procedure itself usually takes about 20 minutes. Plan to have someone drive you home after surgery.
What Should I Expect After LASIK Eye Surgery?
Your eyes will be dry, even though they may not feel that way. Your doctor will give you prescription eyedrops to prevent infection and inflammation, as well as drops to keep your eyes moist. You might have a brief, slight burning feeling or blurry vision when you use them. Do not use any eyedrops without asking your doctor about them.
PRK, or photorefractive keratectomy, is used to correct mild to moderate nearsightedness, farsightedness, or astigmatism. Like LASIK, a surgeon uses a laser to reshape your cornea. But it only affects the cornea’s surface, not the tissue underneath. Your doctor may also use computer imaging of the cornea.
RLE and PRELEX
RLE stands for refractive lens exchange. Other names include PRELEX, clear lens exchange (CLE), clear lens extraction (CLE), and refractive lens replacement (RLR). It’s the same as cataract surgery. The doctor makes a small cut at the edge of your cornea. She removes your natural lens and replaces it with a plastic lens implant. The procedure can correct extreme farsightedness or nearsightedness. It works well for people with thin corneas, dry eyes, or other minor cornea problems. A LASIK or LASIK-related procedure can be combined with RLE to correct astigmatism.
PRELEX, short for presbyopic lens exchange, is a procedure used for presbyopia, or loss of flexibility in your eye. The doctor removes your lens and replaces it with a multifocal lens.
Intacs are also known as intracorneal ring segments, or ICR. The doctor makes a small incision in your cornea and places two crescent-shaped plastic rings at the outer edge. The rings flatten your cornea and change the way light rays focus on your retina. ICR was used to treat nearsightedness, but that has been replaced by laser-based procedures. Now it’s used to fix keratoconus, an irregular-shaped cornea that causes your cornea to thin and results in vision loss.
Phakic Intraocular Lens Implants
Phakic intraocular lens implants are designed for people who are too nearsighted for LASIK and PRK. The doctor makes a small incision at the edge of your cornea and either attaches the implant lens to your iris or inserts it behind your pupil. Unlike RLE, your natural lens stays in place. Visian ICL is the main type of phakic lens implant used.
LRI is short for astigmatic keratotomy. It isn’t laser eye surgery, but a surgical procedure used to correct astigmatism. When you have astigmatism, your eye is shaped like a football instead of being round. The doctor makes one or two incisions at the steepest part of your cornea. This helps it relax and makes it more rounded. This procedure can be done alone, or in combination with other laser eye surgeries like PRK, LASIK, or RK.
Are These Surgeries Safe and Effective?
Their good results are well-documented, but like any surgery, there can be side effects. It’s important to keep them in mind.
Infection and delayed healing. A tiny number of people get an infection after PRK or LASIK. It generally means added discomfort and a longer healing process.
Undercorrection or overcorrection. You won’t know how well the surgery worked until your eye has healed properly. You may still need glasses or contacts. If your vision isn’t great, a second laser surgery, called laser enhancement, can help.
Worse vision. It’s rare, but some people see worse than before the surgery. Irregular tissue removal or excess corneal haze are the usual culprits.
Excess corneal haze. This can be a part of the natural healing process after PRK. It usually has no effect on your vision after and can only be seen through an eye exam. Sometimes it can affect your vision. You may need a second procedure.. Also, a medication called mitomycin C (MMC) during PRK surgery can prevent it.
Regression. Sometimes the effects of surgery go away over a period of months from atypical healing. You may need a second surgery to improve your vision.
Halo effect. This happens in dim light and can make it hard to drive or see in dark places. As your pupil opens, the untreated area outside your cornea produces a second image. It can happen after LASIK or PRK. Your doctor can use laser optical zones or wavefront technology, which creates a 3-D version of your eye so your surgery is more precise, to make it less likely. Higher degrees of nearsightedness with LASIK and PRK increase the halo risk, while Visian ICL for higher nearsightedness has less halo risk.
Flap damage or loss. LASIK leaves a hinged flap on the center of your cornea. It may need to be repositioned during the first few days after surgery or after a severe direct injury to your eye.
Eyeglasses, contact lenses and occlusion therapy in children can fail for a number of reasons. Conditions of developmental delay such as autism, cerebral palsy and Down syndrome may make the patient’s compliance with these methods of correction extremely difficult. Many of the children hesitate and don’t like the sensation of eyeglasses touching their face. In cases of high ametropia, eyeglasses can be difficult to wear due to prismatic aberration, reduced field of vision through the lenses and cosmetic appearance. The placement of contact lens is a challenging task in all children, whether developmentally appropriate or not.
The main reasons for undergoing a refractive surgery in the pediatric population are anisometropic amblyopia and bilateral high ametropia. The role of refractive surgery for high accommodative esotropia has also been highlighted in some studies. Elimination or drastic reduction of anisometropia equalizes the visual input of the two eyes and averts favoring one eye over the other. Likewise, correction of the high refractive error helps in improving the quality of visual input to both the eyes. As stated earlier, spectacles for high myopia and hyperopia can reduce the image quality, which can compromise visual input to the eyes. Therefore, the refractive surgery is an important consideration in such cases.
Many of the treatments used in adults for refractive correction can be applied to pediatric cases. Laser vision correction, phakic intraocular lenses, clear lens extraction and limbal relaxing incisions can all be used to improve children’s vision. Correction of moderate to high refractive error remarkably increases the chances of developing an optimal binocular vision by firstly achieving a refractive equilibrium and, secondly, by eliminating aniseikonia due to anisometropia. High myopia and hyperopia both can be treated surgically.