LASIK: A brief guide

LASIK surgery is an effective treatment option for nearsightedness, farsightedness and astigmatism. If you’re considering laser surgery, here’s what you need to know about this procedure.

LASIK (Laser-Assisted-In-Situ-Keratomileusis) treats refractive errors by folding back the top layer of the eye and re-shaping tissue underneath. Like other laser eye surgeries, LASIK treats vision impairments by reshaping the cornea to correct the way light is focused on the back of the eye.

Since its invention in the early 90s, LASIK has been the most popular surgical treatment method to correct nearsightedness, farsightedness and astigmatism.

With LASIK, a surgeon cuts a sliver of tissue, essentially creating a flap at the front of the eye to expose the inner layers of corneal tissue to an excimer laser. Surgeons will either use a mechanical instrument, called a microkeratome, or a femtosecond laser to create the flap.

When a femtosecond laser is used to create the LASIK flap, the procedure is described as Femto-LASIK surgery. This type of laser is extremely short-pulsed and near infrared. Its high peak intensity over a very short pulse duration (within a few femtoseconds of time) allows for micro-precision single cuts or planes in the corneal tissue without affecting the surrounding tissue.

After the flap is folded back, an excimer laser treats the eye for the individual refractive error. The laser only ablates the necessary tissue, leaving the surrounding tissue unaffected.

• Standard procedure: LASIK has been the standard treatment for over 20 years, and many surgeons are very experienced with this procedure.
  
• Quick recovery: Typically, vision becomes clearer within a couple of hours after surgery and gradually stabilizes over the following weeks.
  
• High availability: LASIK is currently the most popular and prevalent form of laser eye surgery. Most clinics offering Laser Vision Correction have the technology available for this procedure.

Before and on the day of surgery

Before surgery patients are usually directed by their doctor to:

• Stop wearing hard contact lenses for at least four weeks and soft lenses for two weeks before surgery, because they may interfere with preoperative diagnostic tests.
  
• Don’t make-up, perfume or lotion the day before and on the day of the procedure. These products may leave debris around the eye and eyelashes, which increases your chance of infection.
  
• Arrange for alternative transportation directly after the surgery, if you usually drive yourself, and possibly for the next few days following surgery.

After surgery, it is recommended to:

• Not rub the operated eye, and to rest and not overexert yourself.
  
• Wear protective glasses the day after surgery to prevent accidentally moving the flap by rubbing the eye.
  
• Wear a patch while sleeping for a week to avoid accidentally scratching the eye and moving the flap.
  
• Use eye drops for a few days following the surgery to prevent infection and alleviate dryness.
  
• Avoid strenuous contact sports for at least two weeks.
  
• Doctors require a follow-up exam the day after surgery and again a month.
  
• Within a few days after treatment, patients are normally able to drive, work and wear make-up

No surgical intervention is completely free of risks and side effects. Your ophthalmologist can highlight all potential risks and will decide whether you are eligible for surgery.

However, the below can occur after surgery:
Flap-related complications: 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. Complications with the flap after surgery may include infection, inflammation, and dislocation of the flap.

Dry eye syndrome: This symptom can occur after LASIK vision correction surgery. 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.