Photorefractive Keratectomy

PRK is a type of laser eye surgery that is done in order to help correct the vision of a person which can help to reduce any type of dependency on contacts or glasses. This procedure is something that will change the overall shape of the central anterior part of the cornea permanently using excimer lasers to remove amounts of tissue located in the stroma that is located in the cornea which is at the front of the eye, which is found underneath the corneal epithelium. The outermost layer of the cornea will be removed before any tissue is removed by ablation.

During this procedure, a computer system will start to track the eye position of the eye 60 to 4,000 every second depending on the type of specifications of the needed laser. The computer will then redirect any laser pulses for precise placement of the laser. Many modern lasers are able to center on a visual axis and it will then stop if your eye starts to move out of the range of the laser, but it will start over after the eye has been re-centered.

The epithelium or the outer layer of the eye’s cornea is going to be a rapidly re-growing but soft layer that is found within the eye next to the tear film which is able to replace itself from the limbal stem cells after just a few days without any type of clarity loss. The layers of the cornea that are deeper, unlike the epithelium will be laid down early during your life and will have a very limited capacity to regenerate. The layers that are the deepest whenever they are cut by a microtome or reshaped a laser will stay that way for the rest of your life with limited change or healing.

The use of photorefractive keratotomy will take the epithelium of the cornea and cut it off and then remove it. This is what allows your cells to start to regenerate right after surgery. This type of procedure is going to be different from Lasik, which is a type of laser surgery for the eye, where a flap of the eye is made within the cornea’s deepest layers.

PRK and Lasik are going to be two very different procedures. Even though both of the procedures will deal with the epithelium that is on top of the cornea, but PRK will remove this layer entirely, while Lasik will just take the material and push it aside before they decide to put it back for the eye to start healing after having laser surgery. This procedure could be used to farsightedness, astigmatism or nearsightedness. It is during this procedure that the epithelium will be removed using a solution of diluted alcohol.

PRK has a lot of advantages over Lasik as it is able to avoid complications that often come with the flap creation that is made during the surgery. The procedure even helps to eliminate many chances of developing dry eye symptoms after eye surgery. Because this type of procedure doesn’t need a surgical flap, people who have concerns about any complications or trauma that are introduced by the flap could see a lot of benefits from PRK. People who normally wear contact lenses will have to stop wearing them for a certain amount of time before the procedure can happen.

When you compare this to other forms of laser eye surgery, there are so many benefits that you can have and there are not as many complications, especially when compared to other forms of surgery.

If a person wants to have photorefractive keratotomy, they will have to meet the basic criteria in order to qualify to have the procedure.

They have to have decent ocular health, they have to be older than 18 years old, and they have to have stable refraction error (this means that there isn’t any noticeable changes in the eye within the last year) and it must be correctable to 20/40 or better. If you have myopia, then you need to have between -12.0 to -1.0 diopters, and you cannot be pregnant at the time that you have your surgery. You also have to have realistic expectations of the final results that you will have. This means you have to have a complete understanding of all the benefits as well as the risks that may come. You have to have a pupil size that is less than 6mm while in a dark room, which is considered best, but there are some newer type of lasers that can be acceptable to those who have larger pupils. You will also need an assessment of allergies such as pollen, where your allergies could complicate the eyelid margins that follow after your surgery which could cause bouts of dry eye.

If you happen to have some pre-existing conditions, then it could complicate or cause issues to the treatment. Some of these conditions are type II granular corneal dystrophy, systemic disorders like rheumatoid arthritis or diabetes, ocular diseases like glaucoma, dry eye, or keratoconus, collagen vascular diseases like melting or corneal ulceration, and if you have a history of side effects from steroids.

A systematic review has shown that PRK has a shorter time for recovery and there is less pain associated with it. However, the results between this procedure and Lasik are very similar.

It was during 1987 when Dr. Theo Seiler had performed the very first procedure and then it was followed up by having the procedure done in Berlin, Germany at the Free University Medical Center. It was also performed at the Massachusetts Eye & Ear Infirmary during 1996 and it was done by Dr. Dimitri Azar, a refractive surgeon and ophthalmologist. However, during 1998, Dr. Massimo Camellin, a surgeon from Italy has wrote the very first publication about this procedure and had also gave the name Lasek to another procedure at the same time.