The PRK procedure is less common than LASIK. PRK is performed on those patients who are unsuitable for LASIK surgery due to the characteristics of their cornea or the patient’s activity. For example, for patients that play contact sports or cases where the cornea is particularly thin or has slight irregularities in the curvature of the corneal topography, PRK/EBK would be recommended.
The PRK/EBK treatment is different to LASKI in so much as the Excimer laser is applied directly on to the surface of the cornea (having already removed the corneal epithelium) without the need to create a corneal flap.
The most commonly used method in PRK to remove the corneal epithelium is with an ethanol dilute solution. The EBK technique (EpiBowman Keratoplasty) is the latest advancement in terms of removing the epithelium. It consists of using a specially designed instrument to remove the epithelium while leaving the deepest layer (Bowman Membrane) in tact. This allows for a less painful and quicker postoperative healing process and ultimately higher quality in terms of visual sharpness.
The PRK/EBK procedure is performed using a local topical anaesthetic (drops). The procedure lasts only a few minutes and following a brief stay at the clinic and an initial post-operative check, the patient can be discharged and leave the clinic by themselves.
Should I choose PRK/EBK surgery?
PRK/EBK surgery benefits those who suffer from both short-sightedness and long-sightedness whether it’s related to astigmatism or not. Patients must be over 18 and have a stabilised level of refractive error.
Pregnant women should not undergo LASIK treatment. Before treatment, patients must undergo a full eye examination to check that their cornea is healthy and apt for surgery. For this to be carried out properly, patients must also refrain from wearing contact lenses for at least a week prior to the examination.
Can I have both eyes done at the same time?
Generally, surgery is performed on both eyes simultaneously. However, in certain cases, such as with amblyopia (lazy eye) or when correcting a previous procedure, it’s recommended that each eye be operated on separately.
Does the laser affect the interior of the eye?
No. The laser affects only the out layer of the eye, the cornea.
What happens if I move my eyes during surgery?
During laser eye surgery, patients should remain relaxed and focus on a light so that the treatment can be applied to the centre of the cornea. The laser has a system that follows the movement of the eye allowing it to compensate for any small involuntary movements and meaning the procedure to be carried out correctly. The patient will also be told what position to adopt if they are not looking in the right direction.
Does the surgery have any risks?
All surgical procedures carry some risk and refractive surgery is no exception. However, the procedure is generally very safe.
Some of the complications that may occur include dry eye, sensitivity to light and halos around lights. These side effects do not usually last long and disappear after a few weeks. More serious complications that can affect sight (infection, serious inflammation of the surgical wound, corneal thinning or ectasia) are very rare. A small number of patients may need a further short treatment of PRK/EBK in order to achieve optimum results.
What does the postoperative healing process consist of?
Due to the corneal epithelium being removed, patients may experience some discomfort and take slightly longer to recover their sight. In order to speed up the healing process of the corneal wound and reduce discomfort, a therapeutic contact lens is inserted for 5 to 7 days following the PRK treatment.
The temporary side effects that a patient may experience after PRK/EBK surgery are rare but include dry eye, photophobia, watery eyes and generally feeling under the weather. These side effects will disappear over the course of a few days. It’s vital that patients avoid touching, rubbing or scrubbing their eyes for several days following the operation.
How long lasting is the PRK/EBK treatment?
As long as the procedure is performed when the patient’s vision is still stable, the results should last for the rest of their life since once the cornea has been modified it tends to remain stable. Some cases of a patient’s sight worsening do exist, but this can generally be corrected by performing the PRK/EBK surgery again.
Due to the natural ageing process it’s possible for a patient to develop a cataract that requires surgical intervention. If this happens then the cataract surgery is exactly the same as if the patient had never undergone PRK/EBK surgery.