Photo Refractive Keratectomy

This section discusses the laser eye treatment PRK: what it is, the risks and benefits and the cost.

1. What is ‘PRK?’
2. Who should consider PRK?
3. If I am not suitable for PRK then is there an alternative?
4. What are the risks of PRK?
5. What are the benefits of PRK?
6. What should I ask the surgeon at the consultation?
7. How much does PRK cost?
8. What is the PRK procedure?
9. How long do the effects of PRK last for?
10. What does recovery from PRK involve?

What is ‘PRK?’

PRK stands for PhotoRefractive Keratectomy. This technique was the first laser eye procedure and was popular from the 1980’s onwards. It has been overtaken by the newer LASIK and LASEK procedures although it is still carried out on patients with low refractive errors (mild eyesight problems).

It has treated countless numbers of patients over the years but technology moves on and so newer systems with highly advanced lasers such as Wavefront or Intralase have taken its number one spot.

It was the forerunner for LASIK, although LASIK has become hugely popular due to its speedy recovery time and predictable results.

PRK was the first procedure to use ‘excimer’ lasers (surface level).

Who should consider PRK?

If you are not suitable for LASIK, LASEK or Epi-LASEK then PRK is an option. It is recommended for those patients with large pupils or thin corneas.

What is the difference between this and the newer lasik?

The main difference is that the surgeon removes thin layers of cells from the outer surface of the cornea. With LASIK, he or she will create a small flap (with a ‘hinge’) before folding this back to access the cornea. The cornea is reshaped with a laser.

As regards your suitability, this will be decided upon during your consultation. Your age, lifestyle and current state of health will be taken into account. The shape of your eyes, corneal thickness and eye prescription will also be considered.

Every patient is different and what suits one person doesn’t necessarily suit another. Ideally, your prescription should show an upper limit of -11.0 dioptres if you are short-sighted and +6.0 dioptres if you are long-sighted.

There are a range of medical conditions which would exclude the patient from PRK. These include:

• Glaucoma
• Retinal disease
• Severe dry eye
• Any corneal degenerative disease
• Severe diabetes
• Under 18
• Pregnancy and/or breastfeeding (women are advised to wait until at least 3 months after these).
• Hepatitis C
• Wearing a pacemaker
• Autoimmune diseases
• Arthritis
• Vascular disease

These may rule you out. They are not an automatic exclusion but could result in an increased risk of complications during or after surgery.

If I am not suitable for PRK then is there an alternative?

Yes. If you are advised against PRK then this will be for a very good reason. It may be that you fall outside the recommended treatment ranges (prescription measurements), have an eye condition or a medical condition which would make it unsafe for you to do so.

If so then there is an alternative: implantable contact lenses, known as ICL are used on those patients who are unable to have laser vision surgery.

These lenses are similar to the ones you may have been wearing but the difference is that they are placed inside the eye, behind the cornea, rather than on the surface.

Visit our ICL section for further information.

Implantable contact lenses form part of a system of non-laser or ‘Intra-ocular lens’ treatments.

What are the risks of PRK?

All laser eye surgery carries risks although these are very small. PRK is a safe procedure and one that has been carried out on countless numbers of patients. These patients have been very happy with the results.

However there are complications although these are very rare. It is as well to be informed about these when considering whether to have laser eye treatment or not.

These risks included:

• Dry eyes: this is very common with PRK patients although your surgeon will prescribe eye drops to lubricate your eyes.
• Infection: you will be given antibiotics to prevent any post-surgery infection.
• Decreased night vision: some patients find that their night vision has worsened although their day time vision improves. Avoid driving at night during this time.
• Blurred vision, glare and ‘halos’: these usually disappear after 6 months. The extent of any of these is related to the level of refractive error. In other words, if you have a moderate to high refractive error (e.g. myopia) then blurring, glare or halos will be equally as high.
• Thinning of the cornea: this does become thinner as a result of laser treatment. Not likely to cause any long term problems.

What are the benefits of PRK?

The main one is that of unaided vision. Plus, in around 80% of cases patients do not have to wear glasses or contact lenses.

This is the main selling point with laser vision surgery.

The effects are permanent although you need to bear in mind that your eyesight will change as a result of the ageing process. This is particularly relevant if you are in either your forties or fifties.

What should I ask the surgeon at the consultation?

In our ‘General FAQS’ section, contains a list of questions to ask your surgeon.

These are general in that they apply to any eye procedure.

The following questions apply to PRK only:

• What types of medication will I need to take after surgery?
• Can I have both eyes done at once?
• Do you make an incision during the surgery?

How much does PRK cost?

Prices will vary between clinics but in general, you can expect to pay £700 to £900 per eye for PRK.

What is the PRK procedure?

You will given anaesthetic drops which help to numb the eye.

The surgeon then uses a laser to remove the outer layer or ‘epithelium’ of the cornea, which allows access to the cornea itself. He/she will then use the laser to remove tissue from the middle layers (stroma) of the cornea. This reshaping will improve the focussing power of the cornea.

The surgeon will then place a ‘bandage’ contact lens over the treated eye which helps to protect it.

The removed outer layer or epithelium is re-grown by the body after 5 to 7 days.

It will be two months before you see the full outcome of this surgery.

How long do the effects of PRK last for?

The effects are usually permanent. However, if you are aged 40 and over then your eye will change as a result of ageing. If so, then you may require further surgery although this may cost less than the original procedure.

What does recovery from PRK involve?

The difference between this procedure and Lasik/Lasek is that PRK affects pain fibres in the surface of the cornea. This will result in pain and discomfort following surgery but painkillers can deal with this.

The level of pain experienced will vary from one patient to another.

You will also be advised to use eye drops (lubricate the eyes) and possible sleeping tablets.

It will be a week before you can return to work and your normal everyday activities.

The cornea itself can take 3 to 6 months to fully heal.

These results take longer than those for LASIK.