How Does LASIK Work?

Understanding LASIK eye surgery

LASIK is a type of laser eye surgery that may help reduce the need for glasses or contact lenses. Many people choose LASIK to help with short sightedness, long sightedness, or astigmatism.¹ https://www.mayoclinic.org/tests-procedures/lasik-eye-surgery/about/pac-20384774

LASIK stands for Laser-Assisted In Situ Keratomileusis. While the name sounds complex, the process is quite simple to understand. LASIK works by changing the shape of the clear front part of the eye called the cornea. This helps light focus more clearly on the retina at the back of the eye.

When light focuses correctly, vision may become clearer.

How the eye focuses light

The role of the cornea

The cornea is the clear outer layer at the front of the eye. It bends light as it enters the eye. The lens inside the eye also helps focus light.

If the shape of the cornea is not quite right, light may not focus properly. This can cause blurry vision.

People may experience problems such as short sightedness, long sightedness, or astigmatism. Glasses and contact lenses can help correct these vision problems. LASIK aims to reshape the cornea to improve how light enters the eye.

How LASIK works

Creating a thin flap

During LASIK surgery, the surgeon first creates a very thin flap on the surface of the cornea. This flap is gently lifted.

The flap helps the laser reach the deeper layer of the cornea.² https://www.mayoclinic.org/tests-procedures/lasik-eye-surgery/about/pac-20384774

Reshaping the cornea

A special laser is then used to reshape the cornea. The laser removes tiny amounts of tissue with great precision.

The amount of reshaping depends on the person’s vision and eye measurements.

For people who are short sighted, the laser flattens part of the cornea. For people who are long sighted, the laser may make the cornea steeper. Astigmatism can also be treated by smoothing uneven areas.

Replacing the flap

Once the cornea has been reshaped, the flap is carefully placed back into position. It naturally settles into place as the eye heals.

Stitches are usually not needed.³ https://www.mayoclinic.org/tests-procedures/lasik-eye-surgery/about/pac-20384774

What happens during the procedure

Before surgery

Before LASIK, a full eye assessment is needed.⁴https://www.fda.gov/medical-devices/lasik/what-should-i-expect-during-and-after-surgery This helps the surgeon understand your eye health and vision needs.

Not everyone is suitable for LASIK. Your surgeon will look at factors such as your prescription, corneal thickness, and overall eye health.

You may also be asked about your medical history and any medicines you take.

During surgery

LASIK surgery is usually quick. The procedure often takes about 15 to 30 minutes for both eyes.⁵https://www.fda.gov/medical-devices/lasik/what-should-i-expect-during-and-after-surgery

Eye drops are used to numb the eyes. Most people remain awake during the procedure.

You may notice lights or blurry shapes during treatment, but you should not feel pain.⁶https://www.fda.gov/medical-devices/lasik/what-should-i-expect-during-and-after-surgery

After surgery

Many people notice changes in their vision within the first day. Vision may continue to settle over the following weeks.

Some people may experience dry eyes, glare, or halos during healing. These symptoms are often temporary, but everyone heals differently.⁷https://www.fda.gov/medical-devices/lasik/what-should-i-expect-during-and-after-surgery

You will usually need follow-up appointments to monitor healing.

What vision problems can LASIK treat?

Short sightedness

Short sightedness means close objects look clear, but distant objects appear blurry.

LASIK may help improve distance vision by reshaping the cornea.

Long sightedness

Long sightedness means distant objects may appear clearer than close objects.

LASIK can help adjust the shape of the cornea so nearby objects may become easier to see.

Astigmatism

Astigmatism happens when the cornea has an uneven shape. This can make vision blurry at different distances.

LASIK may help smooth the cornea to improve focus.

Is LASIK permanent?

LASIK changes the shape of the cornea permanently. However, the eyes may still change naturally over time due to ageing.⁸https://pubmed.ncbi.nlm.nih.gov/34241701/

Some people may still need glasses for reading as they get older. This is a normal part of ageing called presbyopia.

Results can vary from person to person.

Who may be suitable for LASIK?

A stable prescription

People are often asked to wait until their glasses prescription has stayed stable for some time before considering LASIK.

Healthy eyes

Healthy eyes are important for laser eye surgery. Some eye conditions may affect whether LASIK is suitable.

Realistic expectations

LASIK may reduce dependence on glasses or contact lenses, but outcomes vary between individuals. Some people may still need glasses for certain tasks after surgery.

A detailed consultation can help you understand the possible benefits and risks.

What are the possible risks?

Like all medical procedures, LASIK has risks and possible side effects.

These may include dry eyes, glare, halos, blurry vision, infection, or changes in vision quality. In rare cases, further treatment may be needed.⁹https://www.fda.gov/medical-devices/lasik/what-are-risks-and-how-can-i-find-right-doctor-me

Your surgeon will discuss the risks and benefits with you during your consultation.

Why a consultation matters

A consultation helps determine whether LASIK may be suitable for your eyes and lifestyle.

At Envision Eye Centre, detailed eye assessments are performed to better understand each patient’s vision needs.

Your surgeon can explain the procedure, discuss possible risks, and answer any questions you may have.

Learn more about LASIK

LASIK is designed to reshape the cornea so light can focus more clearly inside the eye. For suitable patients, it may reduce the need for glasses or contact lenses.

The first step is finding out whether LASIK may be suitable for you.

Take the next step

Take the suitability self test to learn whether laser eye surgery may be right for your vision needs.