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Surface Ablation

An excimer laser procedure that is suitable for people with a thin cornea.

What is Surface Ablation?

Surface ablation (PRK) was the first laser method used to correct eye vision; it is now offered as an alternative choice of laser treatment for patients who may not be eligible for the most advanced treatments such as FemtoLASIK and SMILE. 

The surgery is quick, however recovery may be painful initially and visual recovery can take up to several weeks.

Comprehensive eligibility test
(pre-laser test)

A major step towards the road to surface ablation surgery is the detailed, comprehensive eligibility test. The test consists of various diagnostic examinations and is completely painless.

Our team of experts will determine the power to be treated and consider whether the patient is a suitable candidate or not, and if so, indicate which treatment modalities best suit their requirements to achieve the best possible outcome, which is ideally that of perfect vision without glasses or contact lenses. 

Important notes before pre-laser assessment

  • The entire examination takes about 1.5 hours.
  • If you have a previous ophthalmological evidence or a prescription for glasses, bring them to the test.
  • To ascertain the refraction and examine the fundus correctly, dilating eye drops are added, resulting in a slightly blurred vision after the test. Please avoid driving for 3 hours immediately following the examination.
  • Bring with you any medication that you are taking.

Removal of contact lenses before pre-laser test

Contact lens type Length of time lenses need to be out
before the pre-laser appointment
All soft contact lenses At least 1 week before
Extended wear soft lenses At least 1 week before
Toric soft lenses At least 2 weeks before
Rigid gas permeable
Worn for 0-10 years At least 4 weeks before
Worn for 10-20 years At least 8 weeks before
Worn for 20-30 years At least 12 weeks before
True hard lenses (Polymethyl methacrylate) At least 12 weeks before


Patients are eligible* if:

  • They are over 18.
  • Myopic from -1.0D up to -10.0D.
  • Hyperopic from +1.0D up to +2.5D.
  • Astigmatic from +2.5D up to -4.0D.
  • Have not had significant change in refraction for one year prior to the procedure date.
  • Their eyes no longer tolerate wearing contact lenses.
  • Want to see clearly without glasses or contact lenses.

* This table is intended to serve only as guidance and is not a substitute for a professional eye examination.


Patients will not be eligible if any of the following apply:

  • Diabetes
  • Autoimmune disease
  • Wound recovery problems, keloid susceptibility
  • Amblyopia (lazy eye)
  • Cataract/glaucoma
  • Pregnancy planned within six months
  • Nursing mothers
  • Keratoconus (irregular shaped cornea)
  • Previous herpes infection in the eye
  • Severe dry eye syndrome
  • Wearing reading-glasses only

Risks & Complications

Dry eyes

Dry eye is a common side effect in post -operative stage. For this reason, it is recommended that lubricating eye drops are applied to the operated eyes for a three- to six-month period. Most patients report, however, that they no longer need these eye drops for more than a month or two after surgery. Very few patients will need to put these drops for a longer period of time.

Sensitivity to light

Sensitivity to light may take a few days to resolve. Usually wearing sunglasses help and it is recommended that in the first 5 days after the procedure, sunglasses are worn even inside.

Over- and under-correction

Laser surgery-related side effects may be over- and under-correction. Over-correction means that in correcting the vision we go from minus to the plus side, which nevertheless generally evens out with time.


Infections are extremely rare, and the risk is increased during the first 5 days of the surgery when the eye has the bandage contact lens in. Practicing hand hygiene greatly reduces the risk of infections and also storing the eye drops in a clean place.

Regression of refraction

Moderate regression may occur. This occurs mostly in myopic patients who have more than 6.0 diopters of refractive error and virtually all hyperopic patients.

After excimer laser assisted refractive surgery the cornea tends to regress back toward the original refractive error. The epithelium and the deeper stroma can reshape and reform at different rates and can cause regression.

For myopic patients, regression usually occurs within the first one to three months after surgery. Hyperopic patients may experience regression for a longer period of time. In all cases, it is reasonable to expect regression to stop within the normal six month healing period.

Regression that is severe or continues to progress may be a sign of ectasia.


This is an extremely rare condition where the cornea bulges out reversing the intended flattening effect of the treatment, or it can lead to progressive corneal deformity with thinning and increasing curvature changes, and the cornea can develop an irregular shape. The progressive corneal deformation is called ectasia, sometime requiring collagen cross linkage or corneal transplant.

This complication may occur in 1 out of 10,000 cases.


Corneal haze tends to be caused by an aggressive wound response after surface ablation or Femolasik. In response to the “wound” of laser vision correction surgery ablation, the cornea can become clouded with white cells. Treatment is usually effective, however in very rare instances the cornea will remain scarred.

Other Treatments

Learn More


A femto laser procedure without a flap to get rid of glasses or contact lenses.


A laser procedure to eliminate glasses or contact lenses.

Laser Blended Vision

A laser procedure to minimise dependency reading glasses and distance glasses.

Surface Ablation

An excimer laser procedure suitable for people with a thin cornea.

Ready to correct your vision?