Candidates for PRK
If you’re considering having PRK surgery it’s likely to be on the advice of your consultant, who has ruled out the LASIK procedure.
To have PRK you must be over 18 and have stable vision, which means your prescription hasn’t changed for at least a year. PRK can be used to treat most cases of:
- Myopia (short-sightedness) – by flattening the cornea
- Hyperopia (long-sightedness) – by steepening the cornea
- Astigmatism – by smoothing the cornea into a regular shape
The PRK procedure
With PRK, as with all laser eye surgery, you will attend the surgery as a day patient. Anaesthetic drops will be put into the eye and a lid speculum will be attached to the eyelids to gently hold them open throughout the procedure. This is generally not uncomfortable. A suction ring will keep your eyeball pressurised and prevent it from moving, so that the laser can do its precision work.
Unlike LASIK (which involves cutting out a cornea flap) or LASEK (which involves softening and rolling a flap aside), PRK simply sculpts the cornea from the surface. All three techniques require an Excimer laser to reshape the cornea, but the advantage of PRK is that no cut is made, thereby maintaining the integrity and strength of the corneal dome.
The Excimer laser works by sending computer-guided pulses of UV light into the eye, breaking down a microscopic amount of the cornea in a precisely controlled way. The process takes about 30 seconds; the higher your prescription, the longer it will take. During this time you will hear the loud ticking noise of the laser, and possibly smell burning as the cornea is reshaped. Your vision will be somewhat blurry and dimmed because of the anaesthetic drops used, but there is no sensation or feeling of pain.
Once complete, the surgeon will apply a protective contact lens for better healing and comfort, as well as anti-inflammatory and antibiotic eye drops. If you’re having both eyes treated on the same day you will be given a short rest before surgery begins on the other eye. Otherwise you can leave the surgery almost immediately. You must not drive until your vision is fully restored, although you can go back to work within a day or two.