PRK Surgery

Getting Vision Correction Surgery in Singapore?

Eye conditions such as myopia (short-sightedness) is a very common problem among Singaporeans that unfortunately starts for most people at a young age. Singapore holds the first position in the world for the highest occurrence of myopia in children of ages seven to nine years. This could be due to many factors such as early use of interactive devices, lighting conditions, poor lifestyle habits or even genetics.

With such a high prevalence of myopia in Singapore, it is important for people to educate themselves on the various options available to treat this and other eye conditions besides glasses and contact lenses. Of all possible solutions, vision correction surgery (e.g. PRK, LASIK, ICL etc.) offers a one-time and long-lasting effect that gives the myopic patient clearer vision without glasses.

What is PRK Surgery?

Advanced Surface Ablation is a family of laser eye surgery that includes, PRK (Photorefractive Keratectomy), LASEK (Laser Epithelial Keratomileusis), and EpiLASIK (Laser In Situ Keratomileusis). It helps to correct myopia (nearsightedness), hyperopia (farsightedness) and astigmatism. Advanced Surface Ablation is the predecessor to the LASIK procedure and is still well received and commonly performed.

The process involves the use of Excimer laser to reshape the cornea. The difference between LASIK Surgery and PRK is that the eye surgeon does not need to make a flap in this procedure, but instead, removes the outermost lining of the cornea called the epithelium by various means before applying the laser to correct the patient’s vision.  The preferred method used at W Eye Clinic is PRK.

How can PRK can correct myopia (short-sightedness)?

The excimer laser is used to reduce the power of the cornea so that light rays will not bend as much, and the focal point is then shifted from in front of the retina onto the retina surface instead. This will allow images from a distance to be sharp.

PRK - Myopia Treatment Illustration

How can PRK can correct hyperopia (long-sightedness)?

The excimer laser is used to increase the power of the cornea so that light rays are bent more, and the focal point is then shifted from behind the retina onto the retina surface instead. This will allow images from far and near to be sharp. 

How can PRK can correct astigmatism?

The excimer laser is used to reshape the cornea, by evening out the contour to be more round, like changing the shape of a rugby ball to that of a soccer ball. 

How is PRK performed?

First, your eye surgeon will gently remove the epithelium after application of alcohol.

Next, is to apply the laser directly onto the underlying surface of the cornea to reshape the curvature of the cornea surface.

Lastly, a bandage contact lens will be placed on the eye for better comfort and help the epithelial lining regrow to cover the area.

Alternatively, we can also use the laser to remove the epithelium as well as correcting the patient’s vision but the results are the same for either method.

Video Courtesy of ZEISS

PRK Procedure

Who is suitable for PRK?

PRK is for people who suffer from refractive errors but who have corneas that may not be suitable for LASIK. It is also for people whose jobs or sports put them at risk of eye trauma. The long-term visual outcome of PRK is comparable to LASIK but the recovery period is longer.

You will need to go through a comprehensive pre-procedure assessment, where the Optometrists and Ophthalmologist will check your eyes thoroughly in order to determine your suitability for PRK Surgery. Here are some factors to determine your suitability:

  • Has your vision been stable long enough to have PRK Surgery?
    If your spectacle power is still increasing, it would be advisable to wait till it stabilises.
  • What is your corneal shape and corneal thickness?
    Patients that have evidence of Keratoconus (coned shaped cornea) are not suitable for LASIK. This is a condition where the cornea becomes thinned out and weakened causing unusual astigmatism and poor vision. In these cases, implantable collamer lens (ICL) would be a better/safer option.
  • Are you currently pregnant or breastfeeding?
    Hormonal changes and corneal pressure due to fluid retention can cause vision fluctuations of a woman who is pregnant or currently nursing. To have PRK and other types of vision correction surgery results, it is advisable to undergo the procedure at a time when women is neither pregnant or breastfeeding.
  • Do you have dry eyes?
    If you have an existing condition of dry eyes, you may be advised to have that treated prior to vision correction surgery (e.g. PRK, LASIK etc.) – since the quality and the quantity of tears you produce are factors in the development of dry eyes and can also affect healing after eye surgery.