Photo Refractive Keratectomy - Laser Eye Surgery Guide

Photo Refractive Keratectomy is commonly referred to as PRK. This particular system was the innovative laser eye procedure that gained a huge amount of popularity after it was introduced in the 1980s. More recently, this procedure has been overshadowed significantly since the introduction of LASIK and LASEK methods of treatment due to their quicker recovery time and success rates. Despite this, it is a primary procedure implicated when someone requires treatment to correct low refractive eyesight faults including long-sightedness, short-sightedness and astigmatism.

During the PRK procedure, your eye surgeon will employ 'excimer' lasers to alter the shape of your cornea. In short, this laser works by aiming a pulsing beam of UV (ultraviolet) light towards the cornea area of the eye. Excimer lasers are used to work on the cornea's surface as opposed to below the cornea like in the LASIK system.

Who is considered a suitable candidate for PRK?

PRK is a form of laser eye treatment that may be considered appropriate if you desire corrective procedures but are not considered suitable for LASEK, Epi-LASEK or LASIK. One possible cause of this incompatibility with the latter three methods is if you have either a thin cornea or rather large pupils.

As with many other procedures, there are a number of factors that can prohibit the ability of you to have the PRK procedure performed. A key reason is age, which is a common issue with many elective treatments. For PRK, the minimum age is 18 year old.

Other problems that may cause you to be unsuitable for PRK are associated with the eyes themselves. These are medical conditions such as diseases of either the retina or cornea, glaucoma or if you experience extremely dry eyes.

Other medical issues that may discount you as a candidate include if you suffer from serious diabetes, arthritis, Hepatitis C as well as vascular disease and certain autoimmune disease. The latter is an illness where your own immune system attacks your body, which can cause serious conditions and complications.

Furthermore, if you wear a pacemaker, your eye surgeon may not deem it appropriate to undergo PRK. The same can be said if you are pregnant or breast-feeding. It is recommended that you should leave at least a three-month interval between the end of your pregnancy or breast-feeding and undergoing PRK.

Even if you can relate to any of the above issues, it may still be worth talking to an eye surgeon if you wish to undergo PRK. The conditions named are more guidelines that may make the procedure less straightforward and could increase the probability of side effects or complications. Therefore, just because you suffer from one or more, you may still be able to undergo PRK as your individual suitability is at the disclosure of your eye surgeon.

What are some alternatives to PRK?

If you attend a consultation with an eye surgeon and you are not deemed a suitable candidate for PRK, there are alternative options available to you. These options may be made known to you during this consultation or you may wish to research into them yourself.

The safest alternative to PRK is to ensure you continue to wear any contact lenses or glasses that have been appropriately prescribed to improve your vision. The effects obtained from wearing glasses or contact lenses are the same as laser procedures, in that your vision is clearer as the errors have been resolved. However, this option can be seen as a nuisance and many hope that glasses and contact lenses may be a temporary solution as opposed to a permanent one. In such cases, laser surgery may be the best option to pursue.

The laser eye treatments currently available as alternative to PRK are LASIK, Wavefront LASIK, LASEK, Epi-LASEK as well as implantable contact lenses (ICL). Like with PRK, it is vital that you discuss each option thoroughly with your eye surgeon to ensure you are a suitable candidate. By going through each option one-by-one, your surgeon can advise you on which procedure will produce the best results for you. You will learn that although each of the alternate refractive correction treatments use lasers to alter the shape of your cornea, the way by which they do so varies and some techniques are more suited to some people than others.

If your cornea is rather thin, you are probably most suited to PRK, however, if you do not feel that this procedure is what you are looking for then you may research into Epi-LASIK. This alternative method involves a blade being employed to cut away part of the epithelium that covers the cornea. This does not cut the actual cornea, which makes it ideal for those who already have a thin cornea.

Potential PRK risks

PRK is considered a very safe, routine treatment that has been mastered by many eye surgeons. These surgeons see numerous patients coming through their doors to get PRK and the vast majority of these leave satisfied with the outcome.

As with any type of surgical procedure, there are some associated risks and complications. Despite this, these are generally very rare although it is always worth being knowledgeable about them while you are making your decision about laser eye surgery.

There are a couple of common side effects that are often experienced within the first two days following your PRK procedure. Many patients suffer from slight discomfort as well as sensitivity to daylight. In the subsequent six months, there are further issues that you may experience including small halos appearing around images, a level of glare as well as some vision loss when wearing glasses.

Other risks that are associated with PRK laser eye treatment include:

  • Vulnerability to eye infections, however, to avoid this you will probably be administered some antibiotics and eye drops.
  • Dry eyes are a common issue experienced among those who have undergo PRK. To overcome this, you can use eye drops on a regular basis to provide moisture and lubrication.
  • Lack details being seen in dark environments despite your vision in the light drastically improving. Due to this loss of vision in certain conditions, you should probably not drive during the night.
  • The laser used in PRK can cause your cornea to become thinner, although this generally does not result in longstanding issues.
  • The glare and halos noted above may last longer than six months. In such cases, you should contact your eye surgeon.

Advantages of PRK

In around 80% of PRK cases who got the treatment due to short-sightedness, the patients leave with perfect (also known as "20/20") vision after twelve months without having to wear contact lenses or glasses. This is a huge advantage associated with the PRK method. Not only this, but the fantastic result lasts a lifetime, although it must be noted that eyesight does change as we age so you should be prepared for this.

Your PRK Consultation

Before you undergo PRK eye surgery, you will be required to meet your eye surgeon for a one-to-one consultation. During this meeting, you will be able to discuss the procedure in detail as well as learning about how to prepare for the treatment and what to expect afterwards. You will also be questioned about your medical history and it is vital that you disclose everything to your eye surgeon. This includes any conditions you have had in the past or have currently as well as any medications you have taken.

Some tests may be performed to analyse your suitability for PRK. These examinations may include your eye surgeon measuring how thick your cornea is, as well as the refractive index, pupil dilation and pressure. Once this is completed your surgeon will be able to tell you if you are able to undergo this procedure. If you are, you can them book an appointment for the actual treatment itself.

During your consultation you will also be provided with an estimate as to how much your PRK procedure will cost. The price is variable between individuals as it depends on the amount of work required. In general, the cost of the surgery is around £700 to £900 per eye.

The PRK Procedure

The PRK laser treatment is a quick procedure that takes just 10 minutes for both eyes. It is performed once the patient has been administered local anaesthetic as well as eye drops, which work together to numb the eye. A laser is then used to remove the cornea's epithelium so the cornea can be reached and reshaped. This adjustment of the shape is designed to improve how it focuses light onto your retina.

To protect the eye, a sterile lens will be placed over the eye and during the week following the procedure the epithelium will grow back. You should reap the full benefits of the procedure after about two months.

After your PRK procedure

As stated above, once your PRK procedure has been completed, a special contact lens will be applied to the eye. This must be worn for the first few days following the surgery to allow the eye to heal sufficiently and for the epithelium to regrow. You will be expected to visit your eye surgeon a number of times in the six months after your procedure so that the progress can be monitored.

For a number of weeks after your PRK eye surgery, you may notice that your vision will switch between being blurry and clear and your glasses may be required at times. You will need to use eye drops on a regular basis, as your eyes will be dry, even if it is not noticeable. Your eye surgeon will prescribe these drops and they will tell you exactly when and how to use them – it is important to obey these instructions.

As PRK interacts with the pain fibres on your cornea, there will be a level of pain and discomfort experienced during the recovery period. This can be resolved with over-the-counter painkillers such as ibuprofen. If the pain worsens, consult your doctor or eye surgeon.

The week following your PRK procedure should be taken off work to allow you to relax and rest your eyes. After this week, you are able to go back to performing everyday tasks and can return to your normal daily routine. Despite this quick return, your cornea will no actually fully heal for about three to six months, which is longer than it takes after LASIK procedures.