Eye surgery

For many people, laser eye surgery can correct their vision so they no longer need

glasses or contact lenses. Laser eye surgery reshapes the cornea, the clear front part of the eye. This changes its focusing power. There are different types of laser eye surgery. LASIK – laser-assisted in situ keratomileusis – is one of the most common. Many patients who have LASIK end up with 20/20 vision. But, like all medical procedures, it has both risks and benefits. Only your eye doctor can tell if you are a good candidate for laser eye surgery.

It changes the shape of the cornea (the clear covering on the front of the eye). It is done to improve vision and reduce a person’s need for glasses or contact lenses.

Description
For clear vision, the eye’s cornea and lens must bend (refract) light rays properly. This allows images to be focused on the retina. Otherwise, the images will be blurry. This blurriness is referred to as a “refractive error.” It is caused by a difference between the shape of the cornea (curvature) and the length of the eye. LASIK uses an excimer laser (an ultraviolet laser) to remove a thin layer of corneal tissue. This gives the cornea a new shape so that light rays are focused clearly on the retina. LASIK causes the cornea to be thinner. LASIK is an outpatient surgical procedure. It will take 10 to 15 minutes to perform for each eye. The only anesthetic used is eye drops that numb the surface of the eye. The procedure is done when you are awake, but you will get medicine to help you relax. It may be done on one or both eyes during the same session. To do the procedure, a flap of corneal tissue is created. This flap is then peeled back so that the excimer laser can reshape the corneal tissue underneath. A hinge on the flap prevents it from being completely separated from the cornea. When it was first done, a special automated knife (a microkeratome) was used to cut the flap. Now a more common and safer method is to use a different type of laser (femtosecond) to create the corneal flap. The amount of tissue the laser will remove is calculated ahead of time. Once the reshaping is done, the surgeon replaces and secures the flap. No stitches are needed. The cornea will naturally hold the flap in place.

Folding away the top layer and reshaping tissue underneath

LASIK, Laser-Assisted In Situ Keratomileusis, is a refractive laser procedure used to treat nearsightedness, farsightedness, and astigmatism. Since its invention in the early 90s, LASIK has been the most popular surgical treatment

method to correct refractive errors. Like other laser eye surgeries, LASIK treats vision defects by reshaping the cornea to correct the way light is focused on the back of the eye. A surgeon creates a sliver of tissue, essentially making a flap, at the front of the eye to expose the inner layers of corneal tissue to the laser. Surgeons will either use a mechanical instrument, called a microkeratome, or a femtosecond laser, for this step. When a femtosecond laser is used, the procedure is called Femto-LASIK. Once the flap is folded away, an excimer laser shapes the cornea by removing the exposed tissue. The Femto-LASIK/LASIK procedure is completed when the surgeon closes the flap, returning it to its original position.

Flap-Related Complications:
Flap-related complications are possible after the LASIK procedure because a flap is created in the cornea. Complications with the flap may include infection, inflammation, and dislocation of the flap. Treatment for flap complications may involve eye drops or additional surgery.

What Are the Potential Side Effects?

Like all surgical procedures, no intervention is completely free of risks and side effects. Your ophthalmologist can explain all potential risks to you and will decide whether you are eligible for surgery. However, these are some side effects that can occur after surgery.

Complications with the flap after surgery may include infection, inflammation, and dislocation of the flap. While the flap usually adheres back onto the eye after surgery, it does not completely seal itself back together with the corneal tissue. Since the flap sits on the eye, there is a remote chance for it to be dislodged, especially during contact sports or other activities. Dry eye syndrome: Nerves cut during laser eye surgery may reduce the patient’s blinking frequency and/or give insufficient signals to the tear ducts. Blinking less frequently leads to the eye’s tear fluid evaporating faster than normal, which can result in the eye being less lubricated and drier. Dry eyes after LASIK can cause both discomfort and less optimal visual outcomes, but it typically improves or resolves with time.

Laser eye surgery treatments are clinically proven and established procedures. Like all surgeries, however, laser eye surgery is not free of risks and side effects. Only your ophthalmologist can explain the individual risks and decide whether laser eye treatment is an option. Some complications that can occur are:

Over- or Under-correction:

Not everyone achieves a spot-on refractive outcome after laser eye surgery. The amount of vision correction can vary depending on individual conditions. A residual refractive error can remain, which may mean some patients still need glasses or contacts after surgery. In this case, a follow-up surgery to correct the remaining residual refractive error can be considered.

Night Vision Complaints:

This possible side effect has been described as difficulty with night vision or night driving because of glare or halos around lights in the dark. It is more common in the early postoperative period and it gradually gets better in the majority of cases.

Clouded Vision:

With clouded vision, everything can appear hazy. It is more common for strongly nearsighted patients.

Double Vision:

Complaints of double vision after Laser Vision Correction are rare and usually refer to seeing ghosting around images. This is in distinction to double vision, also medically called diplopia, when both eyes are not properly aligned or there is a problem with the brain fusing the images into one.

Dry Eye Syndrome:

A feeling of dry eye after Laser Vision Correction is relatively common in the early postoperative period and gradually gets better in the majority of patients. Some consider it a part of the healing process. It is usually treated with artificial tears or other treatment options. Patients with dry eye before surgery may be more prone to having dry eye after surgery. A dry eye may cause discomfort and blurring. Patients should be tested for dry eye syndrome before considering surgery.

Bulging of the Cornea:

This very rare phenomenon is known as corneal ectasia and occurs when the front of the eye becomes weak and starts to bulge forward. Glasses, contact lenses, or even a corneal transplant may be required to restore vision. It is similar to a condition called keratoconus. Ectasia may occur any time from shortly after surgery to years later. A careful preoperative examination can reduce the chance of developing ectasia after Laser Vision Correction.

Infection:

There is a very small probability of developing an eye infection after laser eye surgery. It is important to consult with the surgeon if the eye turns red, is painful or there is a loss of vision. Infections can be cured if caught early on but can leave serious damage if they are not promptly treated. Prescribed eye

drops given after the procedure can help prevent infection.