What are the risks?

The technological advancements of the last few years have perfected the accuracy and safety of laser eye surgery and noticeably improved the results. An FDA study conducted in 2006 showed that out of 360 patients after being treated with the MEL80 laser, 92,5% saw 1.0, and 99,5% 0.5 or better without spectacles.

Still, even when the operation is done carefully and adequate pre- and postoperative treatment is applied, surgery is never a completely risk-free venture.

Best corrected visual acuity may decline
Visual acuity without spectacles or contact lenses will be better after the operation. It is still possible that with the best spectacle correction, some patients might not be able to see the smallest characters in the eyesight test table as well as before. The MEL80 laser FDA myopia study, however, showed that the likelihood of this is minute. Not one of the patients lost vision of more than 2 lines in the table and in the case of just one patient of 354 (0.3%) did visual acuity decrease by 2 lines.

Possible vision issues in the dark and decline of contrast sensitivity.
Lasers of the older generation caused the cornea to flatten, due to which the expansion of pupils caused vision problems in the dark.
In Estonia, Carl Zeiss MEL80 and Wavelight Allegretto lasers are used, which have possibility to smooth eye surface in a way that allows the cornea to retain its natural shape. Therefore darkness-related vision problems after being treated using modern equipment are rare. Unfortunately, retaining of the natural shape also requires removal of additional corneal tissue, rendering impossible the preservation of the ideal prolate shape in cases of high refraction errors.

Over- or under-correction and regression of the results.
Results are usually less accurate in cases of severe refraction errors. The initial result may slightly regress during the first postoperative months. The surgery can, however, be repeated after three months or even years later.
Studies have shown that in case of moderate short-sightedness (-6 diopters or less), the results remain; at least after 10 years, no sight-threatening changes in the cornea will appear. Adequate statistical data for severe far-sightedness is unfortunately not yet available.

Corneal inflammation
Sterile corneal cut-section inflammation is rare and mostly responds well to treatment. Infection-caused inflammation is likely to occur in only one patient out of 5 thousand. However, should this occur, prompt treatment is important.

It can be said that laser eye surgery is 5 times safer than wearing contact lenses. When a sight-threatening inflammation occurs in one of 2000 contact lens wearers, only one out of 10000 patients of laser eye surgery ever develop a sight-worsening complication.

The dry eye syndrome
As during the operation, some corneal nerves are severed, the eye might not be able to produce enough tears to sufficiently dampen its surface. For this reason, during the first few postoperative months, artificial tears are implemented. A dry eye causes in addition to discomfort and friction also unstable vision quality.

We use a microkeratome, which leaves the nerve tissue toward the nose untouched; this significantly limits the chance of the dry eye syndrome occurring at all.

Imperfect corneal cut
A complication may occur during the operation due to a microkeratome error or some other unforeseen circumstance. Patients with exceedingly flat or steep cornea run a greater risk of imperfect corneal incision. The imperfect patch will be replaced, so that preoperative vision will remain. If that is the case, laser surgery may not be implemented before 3 months time.

Flap displacement
May occur in the first 24 hours after the operation. A surgical procedure is needed as treatment. Given the right operational technique and postoperative care, the rate of occurrence is less than 1 in 1000. Later flap displacement will not be an issue if there is no corneal trauma.