Laser Vision Correction
An abnormal curvature of the cornea (the transparent layer in front of the eye) causes a visual error, where light passing through it does not focus on the photosensitive retina at the back of the eye, causing a blurred or hazy image. LASIK (laser in-situ keratomileusis) is a procedure that uses a laser to reshape the cornea and correct the error.
LASIK is indicated to correct near-sightedness, farsightedness or astigmatism (irregular curvature of the cornea).
Before undergoing LASIK surgery, you are instructed to stop wearing contact lenses for a period of time. Your doctor will measure the thickness of your cornea, eye pressure, pupil dilation, visual refractive errors and perform corneal mapping.
The surgery is performed under local anaesthesia. A femtosecond laser is first used to create a flap. You are then moved to a second laser called an Excimer laser where the flap is lifted, and the prescription is sculpted into the cornea. The flap is then replaced.
Complications from LASIK include dry eyes, loss of vision, inflammation, needing an additional procedure and regression of the prescription.
Photorefractive keratectomy (PRK) uses the same excimer laser utilised in the second part of LASIK surgery to sculpt the prescription into a more superficial layer of the cornea. PRK is used when a patient’s cornea may not be suitable for LASIK surgery. A protective lens is placed on the eye for 3-4 days until the surface has healed.
Complications from PRK include dry eyes, haze, cloudy or reduced vision and temporary sensation of having a foreign body in the eye.