Photorefractive keratectomy is the very first kind of refractive surgery that was approved by the FDA. There are many people involved in the development of PRK. There were surgeons from Maryland and Washington DC who worked on clinical trials to offer people a way to correct their vision.

What happens during PRK

In a person's cornea, the epithelium-or outer layer-grows very rapidly and replaces itself within a few days. The deeper layers contained in the cornea are not able to regenerate very well. If they are reshaped or cut by a laser or microkeratome they will only heal a little and usually stay the way they have been reshaped. PRK permanently changes the shape of the anterior central cornea by first taking off the outer layer of the cornea and then by removing a small bit of tissue from the corneal stroma. The corneal stroma is located under the corneal epithelium.

PRK candidates

A person needs to meet specific criteria for them to qualify for LASEK eye surgery. To get PRK a person needs to be 20 years of age or older, have normal ocular health, and be near-sighted. Being near-sided means that a person can see objects that are close-by but objects that are farther away are blurry. A near-sided eyeball is longer than an eye that can clearly see objects both near and far.

Both males and females can get PRK but if a woman is pregnant she should not get the surgery. Also, a person needs to have a -1.50 to a -7.00 diopters-which is a unit of measurement of lens' optical power-of near-sidedness and in room light the person's pupil needs to be 6 mm.

There are also a few things that could complicate the eye surgery. If a person has rheumatoid arthritis or diabetes, glaucoma, keratoconus, corneal ulceration, or side effects from steroids then it may complicate or prevent someone from getting PKR.

Complications from PRK

Just as with any surgery, PRK eye surgery also has a list of possible complication that someone could experience after having the surgery. Possible complications of PRK eye surgery include: pain, a long healing period, dry eyes, corneal haze, scarring, starburst Aberrations, halos, and glare, recurrence of near-sidedness, and over- or under-correction.

Sometimes there are surgical complications and a PRK patient could lose their best corrected visual acuity. But the surgery improves people's vision more often than it causes people to lose vision.

Differences between PRK and Lasik

PRK can be considered safer than LASIK. During PRK there is no flap-which is part of the corneal tissue that is cut from the remaining part of the cornea with a hinge left. There is also no blade involved. This means that if someone gets PRK they are eliminated from a lot of the risks and serious complications that come from LASIK. And since PRK does not use microkeratome or a knife, the structural integrity of a person's cornea is less altered for PRK patients. But PRK patients can have more discomfort during healing compared to patients who have LASIK. Also, LASIK patients tend to have faster visual recovery compared to PRK patients.