Refractive Laser Surgery (Lasik and PRK)

Refractive laser surgery (Lasik and PRK) reshapes the front surface of the eye (cornea) using an eximer laser. The laser utilizes energy in the form of an ultraviolet beam which does not burn or cut tissue. Through the process of ablation, molecular bonds disintegrate as the laser beam strikes each grouping of cells. Ablation removes corneal layers precisely with little or no damage to surrounding cells. A computer is used to control the beam as it reshapes the cornea in the desired fashion. In most cases, only 10 to 15% of the thickness of the cornea is removed. Actual laser surgery time is only 10 to 90 seconds per eye. Both procedures are performed using topical anaesthetic drops, which numb the surface of the eye.

Refractive laser surgery techniques are used to treat myopia, hyperopia, and astigmatism. Presbyopia, the condition that requires individuals over 40 to wear reading glasses or multifocals, cannot be treated. Individuals that already require bifocals would only be able to receive laser treatment for their distance vision, hence still requiring reading glasses after. The Optometrist will discuss the pros and cons of refractive surgery and the outcomes that would be expected for the patient.

PRK Surgery

With PRK (Photorefractive Keratectomy), the epithelium is removed by gently scraping the tissue layers over the entire surface to be treated. Then the laser re-sculpts the middle layer of the cornea. Finally a bandage contact lens is positioned over the treated area until the epithelium reseals, usually within 3 to 4 days.

Lasik Surgery

Lasik (Laser In Situ Keratomileusis) is a very technologically advanced procedure and requires great skill. Using an instrument called a micro keratome, the surgeon separates the surface layers of the cornea, creating a flap which is gently lifted back. The laser then re-sculpts the middle layer of the cornea. After the laser has removed the selected tissue, the flap is repositioned over the treated area and adheres to the rest of the cornea within minutes. The cornea has extraordinary natural healing qualities that allow effective healing without the use of stitches. Caution must be taken, however, to avoid disturbing the flap for the first few months of healing.

Visual recovery is much faster with Lasik, permitting return to work and driving, often within days of surgery. Postoperative discomfort is significantly reduced following Lasik.

Intrastromal Ring (KeraVision Ring)

The KeraVision Ring is a new technology designed to correct myopia (commonly known as nearsightedness). The KeraVision Ring consists of two tiny plastic half-rings that are placed within the tissue at the outer edge of the cornea. The KeraVision Ring is designed to correct vision by reshaping, or flattening, the cornea without surgically altering the central optical zone, which is critical for clear vision. Other surgical procedures, which cut or remove tissue from the central optical zone, make irreversible changes to this area. The KeraVision Ring possibly provides greater flexibility, because it is removable in cases of prescription changes or incompatibility (rejection).

The KeraVision Ring is made of the same medical plastic that has been used for nearly 50 years for contact lenses and the intraocular lenses that cataract patients receive.