Photo-reactive keratectomy - PRK - is a more established and traditional form of laser eye surgery which has been available for over 10 years. It is also known as LASEK and is normally used for the treatment of mild and moderate short sightedness -3 to -5.75 dioptres.
Indications
Mild to moderate short sightedness. It is not recommended treatment for very low levels of correction, i.e. less than -1 dioptre. You should normally be healthy, over 20 years of age and the eyesight should not have changed significantly in the last few years. You should have had glasses since childhood or early adult life.
This treatment is not recommended to people who develop the need for reading glasses over the age of 40. This is more likely to be due to crystalline changes than in the lens for which the technique is not suitable.
This technique is not recommended for patients with a lazy eye, partially sighted, blind in one eye, diabetics, people suffering from rheumatoid arthritis or collagen diseases. It should also be avoided in pregnant women.
Anaesthetic
It is normally done under local anaesthetic as a day case.
Technique
A consultation and full examination to determine the health of the eye and the type of correction may be performed on the same day of surgery.
Following this the doctor applies anaesthetic eye drops and a small clip used to keep the eyelid open. The outer surface of the skin of the eye is softened and folded aside. A target light is then shone in the eye and the laser applied for around 30 seconds to a minute.
The whole procedure takes around 15 minutes. Following the procedure the eye is patched or a clear contact lens fitted. Eye drops are given to aid the healing process.
Time in Hospital
This is normally performed as a day case although it is normally recommended that you have a friend to drive you home and that you avoid driving and using machinery for the first 24 hours.
Time off Work
As the outer surface of the eye or epithelium is preserved recovery time is much shorter compared to the standard LASIK treatment and is normally not so painful. The following day it may feel as if your eye is sore.
Whatever you do you must not scratch or press on your eye under any circumstances. The surface of the eye normally heals within the first few days, during which the vision returns to normal.
Do not plan any activities for 36 hours following treatment. It may be useful to have any children looked after for the first 36 hours and you will not be able to return to work for 3-4 days. Return to work is normally governed by the improvement in vision.
You might find the vision fluctuates during the first few weeks and will be noted to be dimmer during the follow up because this is normally is arranged just to check the healing process is satisfactory. It is not recommended that you drive until the eye feels comfortable. If one eye has been treated it is normally recommended not to drive for the first 5-10 days. Care must be taken at night as reduced night vision may occur. You can resume normal activities after 10-14 days.
You might well note that in the first few months that the eye appears to be more long sighted. However this normally resolves. If it becomes a problem you may well be given a contact lens to wear.
It is important to avoid strong sunlight and dusty environments. You should avoid swimming for one month to decrease the chance of infection.
Risks and Complications
Apart from tenderness and grittiness during the first few days there may be some slight visual disturbance. However these normally respond within the first few days
