Overview

Laser eye surgery can correct common eye disorders such as short-sightedness, long-sightedness (in some people), and astigmatism (depending on the type and the severity). See "An insight into eyesight" below.

The surgery works by re-shaping the cornea - the front surface of the eye. The cornea is flattened for short-sighted people, sculpted to a steeper curve for far-sighted people, and evened out to correct astigmatism. It's all over in a flash - the entire surgery takes less than 15 minutes.

There are seven laser-surgery clinics in New Zealand and all clinics use trained ophthalmologists (eye specialists who go through medical training before specialising). They are qualified to diagnose and treat a wide range of eye diseases and also carry out eye surgery.

All surgeons are Fellows of the Royal Australian and New Zealand College of Ophthalmologists.

An insight into eyesight

The eye works like a camera - its primary function is to focus light.

For the eye to see, light rays must be bent or "refracted" to meet at a single point through the cornea. The cornea at the front of the eye provides most of the focusing power.

In the normal eye, light rays pass through the cornea and the lens behind it focuses them as a sharp image on to the retina at the back.

"6/6" vision is the term for normal vision. The old term for 6/6 "normal" vision was 20/20, referring to feet instead of metres. A person with 6/12 vision can see at six metres what a person with normal vision can see at 12.

Images are blurred or distorted when the cornea or eye is misshapen.

The most common vision distortions are myopia (short-sightedness or blurred distant vision), hyperopia (long-sightedness or blurred close-up vision), and astigmatism. In astigmatism the cornea is uneven, leading to blurred vision at all distances.