Laser Eye Surgery - Risks and possible side effects of laser eye surgery
Here are some of the risks and possible side effects of laser eye surgery. Always consult your surgeon for the full list of risks before consenting to surgery.
Some people have a problem with dry eyes after laser eye surgery and in some cases artificial tear supplements might be needed to overcome this problem. Dry eye is actaually a very common condition, but it usually affects people over 40, especially women. It is important to know if your eyes are chronically dry, because this condition can affect healing after laser eye surgery. The symptoms include stinging or burning eyes, excessive tearing and difficulty with wearing contact lenses.
If you think you may have chronically dry eyes, ask your eye surgeon to administer the Schirmer test. It is a simple test, a thin piece of paper will be placed on your eye and left for a few minutes. When the paper is removed the amount of moisture on the paper is measured. Some patients experience dry eyes post-operatively. For almost all patients, dry eye symptoms gradually subside over the first few weeks or months after laser eye surgery surgery. If you suspect that you may have post-operative dry eye, you should contact your doctor's office for an evaluation.
Loss of night vision/ visual quality
This problem cannot be corrected with spectacles. According to Moorfields Eye Hospital 49% of LASIK patients had a significant loss of night vision 12 months after surgery. Other laser eye surgery centres show similar results. There are several potential causes of decreased night vision. The most common being mild swelling of the flap, which should reduce after a few weeks. Research has been published stating that patients who have pupils that exceed the ablation zone may be more likely to experience decreased night or low-light vision following laser eye surgery.
Glare/halos starburst effects
Many patients see glare or halo effects when night driving, particularly immediately after laser eye surgery. This is more likely the higher the correction that has been made, but it is rarely severe. These symptoms usually subside within by six weeks or so for the vast majority of patients who experience them. However, some will continue to experience them for a greater length of time. Depending upon the cause, those patients who experience significant, persistent glare, halos or starbursts have several treatment options. Enhancement procedures may be an option, but not everyone is eligible for an additional procedure. Eligibility for enhancements depends on a number of factors that a doctor must evaluate. For some patients, prescription eye drops to prevent dilation of the pupil at night to reduce the symptoms of decreased night vision may be an option. However, this pharmaceutical approach is not successful for all people, and it also can represent a significant expense over time. Diagnosis and treatment of clinical dry eye may alleviate many of the symptoms. Toric contact lenses may be prescribed for those who have astigmatism. Future advances in laser technology offer great promise.
The accepted remaining corneal thickness for safety has increased to 325 microns. In the last few years many eyes have been left with less than 250 microns and their long term prospects are unknown as their strength will have been reduced by 40-50%. Special contact lenses, corneal tranplants in severe cases. This complication has a very long time of manifestation, so true extent of the problem is not yet known
Dislodged cornea flap
The flap of cornea may become dislodged either during, or a few days after the procedure but this is very rare and unlikely. Every possible precaution is taken to avoid this problem. Should it arise a minor procedure would be required for your surgeon to re-position the flap.
Poor corneal flap
An incomplete or irregular flap has been reported but this is often related to poor quality instruments. Creating a cap rather than a flap of corneal tissue by fully removing the top of the cornea can occur with very flat corneas. Conversely the flap can develop a "button-hole" when being cut, if the cornea is too steep but again this is extremely unlikely in experienced hands.
Infection can occur as the eye is exposed. You would be given antibiotic drops to prevent this.
Very rarely the surface cells can grow under the flap (epithelial in-growth), or debris may become trapped under the flap. This can seriously affect vision. Re-treatment of the flap would be necessary in this very unlikely event.
Sources and further risk information