Your eye usually works like a perfectly focused camera, where the focusing mechanism of the cornea (the clear window at the front of the eye) and lens brings light to a focus on the retina (the camera film at the back of your eye).
Sometimes light may not be focused properly due to problems with the structure of your eye. These include short sightedness, far sightedness and astigmatism. These are collectively known as refractive errors.
The branch of ophthalmology dealing with surgery to correct refractive errors is known as “refractive surgery”.
Laser vision correction is a type of surgery that improves the focusing power of the eye where an excimer laser (cool temperature laser) is used to improve the focusing power of your eye. This is done by using the laser to change the curvature of the cornea (the clear window at the front of your eye).
Vision which becomes clear upon using spectacle or contact lenses is a refractive error.
An error of refraction is usually diagnosed after testing by an optometrist or an Ophthalmologist.
Tests which are needed to determine if you are a good candidate for vision correction surgery include:
Laser vision correction surgery can be divided into two general types (i) surface laser treatment and (ii) LASIK.
1. Surface laser treatment is a form of laser surgery that does not involve any cutting. In this, an excimer laser is applied directly to the cornea to change its shape. The main advantage of surface treatments is its excellent safety profile due to it being a no-cutting technique. The main disadvantage is that of a delayed (1 week) recovery period and stinging and watering after surgery. there are several techniques used for surface laser:
2. LASIK is a technique where a thin flap is cut on the surface of the cornea. This flap is then lifted up and the excimer laser is applied underneath the flap. The flap is then put back in place. The main advantages of LASIK are a rapid recovery along with increased levels of comfort. The LASIK flap can be created with either: