Risks and Complications

Now that you have an understanding of how laser eye surgery is able to reduce or eliminate your dependency on your glasses or contact lenses, it’s also important to understand the possible risks and complications that are associated with laser eye surgery. All types of surgery carry the risk of complication and neither cTEN nor LASIK are exceptions to that principle.

Over & Under Correction

This is the most common complication. In the few patients that this occurs in, under correction tends to be more common. This may be corrected with further laser eye surgery known as an ‘enhancement’. Enhancements are usually carried once the healing response to the initial procedure has stabilised.

Glare & Haloes

Some patients experience glare and haloes around bright lights in darker conditions, for example, oncoming headlights driving at night time. These may be permanent to a small degree. Most patients do not find them a serious issue often being the same as experienced before the operation with contact lenses in particular.


This complication refers to the tendency of the eye to return towards the original refraction after laser eye surgery. Mild regression may require the use of corrective lenses, glasses or contact lenses for specific activities such as driving at night time. Most forms of regression post laser eye surgery can also be treated with enhancements.

Corneal Haze

The healing response results in some haze on the front of the eye in almost all patients, but is only visible to the surgeon under a microscope. It is usually gone by 6 months after the procedure and very rarely affects vision.

Flap complications (LASIK Only)

Complications involving the flap during a LASIK procedure are exceptionally rare, but are possible. During the fashioning, manipulating or repositioning the flap, there are a number of things that may occur. Your surgeon will discuss this with you if LASIK is planned for your eye.

Ocular Tenderness / Recurrent Erosion

Occurring more commonly amongst PRK patients, the new layer of epithelium cells takes a number of weeks to seal completely to the tissue beneath. Until this occurs, it may cause minor irritation that is usually only noticed by patients when questioned about it and happens mostly in the morning. Breaks in the new epithelium layer may also occur, but can be treated and settle with time.


As with any surgical procedure, infections can be introduced into exposed tissue. These are exceedingly rare in laser eye surgery, and such infections are treatable if they should arise.

This is not an exhaustive list of complications, but does cover a majority of complications that occur worldwide in association with Laser Vision Correction. At the time of your assessment, your surgeon will explain the possible risks and complications associated with laser eye surgery in greater detail.