LAser in SItu Keratomileusis (LASIK) 

LASIK is a type of refractive surgery. This type of surgery uses a laser to treat vision problems caused by refractive errors. You have a refractive error when your eye doesn't focus light properly.

 

To see clearly, light rays must travel through your cornea and lens. The cornea and lens refract light so that it focuses on the retina. The retina converts light into signals that are sent to your brain and become images. When you have refractive errors (nearsightedness, farsightedness, astigmatism), the shape of your cornea or lens prevents light from focusing properly. When light is not focused on the retina as it should, your vision is blurred.

 

With LASIK, your eye doctor uses a laser to change the shape of your cornea. This improves the way light is focused on the retina. LASIK is used to treat nearsightedness (myopia), farsightedness (hyperopia), and astigmatism.

 

The goal of LASIK is to correct your refractive error to improve your vision. 

 

Who is a good candidate for LASIK?

To undergo LASIK surgery, certain conditions must be met. Some of them are:

 

You must be 18 years of age or older (ideally, over 21 years of age, when your vision is most likely to have stopped changing).

Your eyeglass prescription shouldn't have changed much in the last year.

You need to have realistic expectations about what LASIK can and cannot do for you.

Some people are not good candidates for LASIK. They include people with:

 

• an unstable (changing) refractive error
• extreme levels of myopia, hyperopia, or astigmatism
• severe dry eye
• corneal defects or corneal disease
• corneal erosions or diseases
• advanced glaucom
• cataracts affecting vision
• certain eye infections
• uncontrolled diabetes
• pregnancy

A detailed examination and preoperative screening will show whether you are suitable for LASIK surgery.

 

What to expect with LASIK?

Before surgery

You and your eye doctor will discuss your vision needs based on your lifestyle. For example, if you are involved in sports, are a professional driver…

The ophthalmologist will carefully examine your eyes to determine if you are a good candidate for LASIK. The procedure includes:

 

Your vision test. This is done to confirm that your vision has not changed. It also shows how high your refractive error is and whether LASIK can be used to correct your vision.

Checking for other eye problems. The eye doctor will make sure that you do not have any eye problems. This is because other problems could affect your surgery or its prognosis. For example, if you have dry eyes, it may become worse after LASIK.

Measuring and mapping your corneal surface. The ophthalmologist will check the thickness of your cornea and take precise measurements of the corneal surface. The surgeon uses these measurements to program the laser used during surgery.

Measurement of the pupil size of the eye. If the pupil is too large, you may notice ghosting at night after LASIK.

During LASIK

Your eye will be anesthetized with eye drops.

Your surgeon will place an eyelid dilator in your eye to prevent it from blinking. A suction ring will also be placed in your eye to keep it in place. You will feel pressure, like a finger pressing firmly on your eyelid. At this point, your vision may become blurred.

Using either a device called a microkeratome or a (femtosecond) laser, your eye doctor will create a flap in the corneal tissue. The flap is then lifted.

You will be asked to look at a bright target without moving your eyes. The surgeon will use a laser to change the curvature of the cornea. 

After the laser is completed,will put in a contact lens

After LASIK

Your eye doctor may place a protective covering over your eye. This helps protect your eye while it heals.

You should return home and sleep or simply relax after the surgery.

For a few hours, your eyes may feel like they have a foreign body or “sand.” You will be given special eye drops to reduce dryness and help your eyes heal.

What are the risks with LASIK?

Like any surgery, LASIK carries risks of problems or complications that you should consider. Most are temporary and resolve within the first few days 

 

These can include:

 eye pain or discomfort, blurred vision, light sensitivity, redness of the white of the eye

Other rare risks include:

 eye infection, worse vision than before LASIK, even with glasses or contact lenses 

Also, in a very small percentage, the refractive error may be over- or undercorrected, in which case additional laser surgery may be required.