Laser Eye Surgery Risks
At Perfect Vision Laser Correction, we won’t take unnecessary risks with your eyesight. We will not accept a patient for any eye treatment unless confident that we can improve their vision.
The final outcome of laser procedures is dependent on the individual healing process of each patient, sometimes resulting in under or overcorrection. Although a final visual outcome can be suggested from studies of large numbers of patients, and visual results can be considered reasonably predictable, the final amount of correction cannot be absolutely guaranteed. For your piece of mind, we offer the Lifetime Enhancement Program. If further laser treatment is required, you can rest assured that you will not be required to pay for the laser enhancement*.
As with all medical procedures, there are risks and side effects that need to be taken into consideration if you undergo laser vision correction. Of course, these will be discussed in great detail during your consultation with your Ophthalmic surgeon.
For your information, we have listed some of the side effects that can occur, and how they can be treated. Fortunately, most side effects and complications resolve within three months of surgery and they do not result in long-term vision problems.
*Terms & Conditions apply
Dry Eye
Cause
Dry eye occurs when there is a temporary reduction in neural communication between the cornea and Lacrimal gland of the eye.
Incidence
Making a LASIK flap severs corneal nerves, so some drying effect is therefore inevitable in patients, but it is only symptomatic in 50% of them. Surface Ablation treatment preserves more of the corneal nerves, thereby resulting in 20% of patients reporting dry eye symptoms.
Management
Patients are routinely given tear supplements for 4 weeks post treatment; those who remain symptomatic after this time (5%) are managed with gel tear substitutes and/or punctal occlusion.
Glare
Cause
The reaction of the cornea to the laser treatment involves a build-up of haze within the cornea. This haze causes forward light scatter, which results in extraneous light causing loss of contrast of the retinal image.
Incidence
All patients experience light sensitivity (photophobia) in the immediate hours following the treatment. iLASIK™ patients see an improvement within 24 hours and the phenomenon dissipates within 7 days. Surface Ablation patients can see more persistent haze, due to the necessity to replenish epithelial cells. All residual haze improves with time to the point where it is not symptomatic.
Management
Patients are advised to attend their treatment appointment with dark glasses to give comfort during the first 3-5 hours post-surgery. Patients are also advised not to use their eyes excessively, avoid brightly lit environments, and not to watch television or use computer equipment immediately post-treatment.
Haloes/Starbursts
Cause
Altering the shape of the cornea with Excimer laser results in a temporary increase in the higher order aberration of the eye. These have the effect of creating haloes around lights (induced spherical aberration), or distorting bright points of light into starburst effects (coma and trefoil aberration). These are more evident in low ambient illumination, hence the fact that they are only reported at night.
Incidence
Temporary night vision difficulties of this type are reported in the immediate post-treatment period by most individuals. Persistent night vision difficulties occur in less than 5%.
Management
The healing process takes time to complete and the aberration increase is evident for approximately 3 months. Individuals who are particularly susceptible can be identified by pre-operative aberrometry using the WaveFront WaveScan™ System (routinely carried out on all Perfect Vision Laser Correction patients), and are advised to opt for CustomVue™ laser treatment, which is specifically customised to reduce total post-operative aberrations.
Night Vision Problems
Cause
The cornea’s healing process causes a loss of contrast sensitivity, which can result in poorer quality vision in low light. Very similar to haloes/starbursts and haze, in that these difficulties are related to the healing processes and are temporary in nature.
Incidence
Loss of low contrast vision is a normal consequence of treatment, but causes symptoms in only a minority of patients.
Management
Once the healing process is complete, the contrast sensitivity shows a return to normal levels without intervention.
Epithelial in-growth
Cause
When making the Lasik flap, but more usually in lifting a flap for a second treatment, some corneal epithelial cells can become trapped. In most cases they will be reabsorbed but, rarely, cytokines (chemicals promoting cell replication) will reach the cells and encourage them to grow through the flap tissue, with the damaging result of tissue loss ("corneal melting").
Incidence
0.9% of primary treatments, 1.7% of re-treatments.
Management
The flap must be lifted and carefully cleaned to remove these cells.