27 Feb Complications of PRK
PRK complications are rare. This has made PRK (Photorefractive Keratectomy) a popular and very successful from of laser eye surgery. It is important to consider the many benefits of PRK surgery, but also the potential complications as you plan for your laser eye surgery.
The Advantages of PRK Eye Surgery
PRK eye surgery leaves the eye stronger than LASIK, making it the first choice for laser eye surgery for many with thin corneas or those that participate in marital arts, contact sports, or contact oriented professions. PRK surgery has been performed in the United States since 1985. We have a long history of success with PRK eye surgery and a good understanding of its long-term benefits and track record. We also understand the potential PRK complications and how to treat them.
PRK problems can be divided into problems or inconveniences during the healing phase and complications. The impact of PRK problems during healing are minimized by carefully following your doctors instructions and allowing adequate time in your schedule for the healing to take place. If you don’t allow three or four days of rest for your eyes to recover from the surgery and resume full activity to quickly, the bandage contact lens placed to aid in healing and maximize comfort can slip out of place, delaying the healing time and unnecessarily elevating discomfort and the risk of PRK problems.
Delayed Healing Time
The clear skin that covers the cornea is called the “epithelium.” This is removed for treatment and heals back for most patients on the third or fourth day after surgery. Some heal more slowly than this, especially if they are more sensitive to the preservatives in the eye drops used after surgery or smoke. This complication could delay your return to work or increase the chances of corneal haze or other PRK problems.
Target Error Complications
Photorefractive Keratectomy surgery is a very predictable form of laser eye surgery and most achieve their desired vision after only one treatment. If the surgery slightly under or over treats your vision you could be a bit nearsighted, farsighted, or have some amount of remaining astigmatism. A mild retreatment (enhancement), glasses or contact lenses could be considered to treat this complication of PRK eye surgery if necessary.
Dry Eye after PRK Eye Surgery
It is common to experience an increase in dry eye symptoms for the first three to six months after laser eye surgery. Most return to their preoperative level of symptoms after the healing phase is completed. On rare occasions, the dryness can last longer or even persist long term and have a significant life impact. This complication is understood to happen less with PRK surgery than with LASIK.
PRK Complications–Glare and Haloes
During the healing phases after PRK eye surgery, most have mild haloes and glare. You should anticipate these PRK complications while you are healing. These completely resolve for most and it is common for patients to have better night driving after PRK surgery without their glasses than they did before surgery with their glasses. Having said that, there are some that have mild or even significant symptoms of nighttime glare and haloes that persist after the healing phase. An additional treatment with the laser could be considered to treat these PRK complications if medically prudent.
Photorefractive Keratectomy is like any other surgery where you may need to take medicines to prevent pain and stay comfortable while you heal. We take a number of steps to make sure you don’t have pain after your PRK surgery. Those steps include a bandage contact lens, eye drops that are similar to motrin (xibrom), a narcotic pill (usually vicodan), and numbing eye drops.
Many are totally comfortable and have no pain after PRK surgery with just the bandage contact lens. The contact lens acts like a bandaid so that you blink on the contact lens rather than the healing edge of the epithelium. We usually remove the contact lens on the forth day.
Other patients use the xibrom drops a few times while others need the vidodan and some of the numbing drops.
We make sure that you have all of these readily available so that you can add these in a stair step fashion as needed to make sure you are comfortable as you heal and don’t experience pain after your PRK eye surgery.
We want your cornea’s immune system to respond to the treatment and heal your eye, but we don’t want it to overreact. This could cause some haze to form on your cornea.
There are steps that can be taken during surgery to help prevent this, like placing some mitomycin on the cornea after the treatment for a few seconds. In addition, anti-inflammatory drops are used after surgery to modulate the amount of healing that takes place.
Excessive exposure to sun while you are healing can increase the chances of corneal haze. It is wise to use sunglasses and a hat during the healing phase if you anticipate being in the sun for extended periods to decrease the chances of having these kinds of rare PRK complications.
Usually the corneal haze, if it happens, is mild and resolves on its own. If the haze is significant the laser can be used to decrease or remove these kinds of PRK complications.
Some individuals are born with weak corneas. These weak corneas can deform into irregular, non-round shapes even without procedure. This process is called ectasia. Ectasia can cause irregular astigmatism. There have been major advances in detecting which patients have inherent weakness in their cornea, but the tests are not perfect.
Laser eye surgery evaporates away part of the cornea and slightly weakens it. If your cornea is already weak, laser eye surgery would hasten the weakening process.
The cornea is stronger after PRK surgery than LASIK for a given amount of treatment so PRK eye surgery decreases but does not fully eliminate the risks of PRK complications from PRK surgery such as ectasia.
In the past, it was often necessary to wear a gas permeable contact lens or have a corneal transplant if significant ectasia developed. There is now an FDA trial underway in the U.S. for a procedure called “cross linking” that is available widely outside the U.S. Crosslinking strengthens weak corneas with ectasia. We hope this procedure will be made more available for the rare patient with these PRK complications.
It is important that you choose a good refractive surgeon that can review all options with you to help you decided which of the refractive procedures is best for you. Our goal is to minimize any PRK problems and to make sure you have the best experience and vision possible.
If I can answer any further questions about potential PRK complications and PRK surgery please leave a comment or schedule a time to meet with me for a consultation.