LASIK induces irregular astigmatism

September 8, 2007

Unlike LASEK, LASIK significantly increases irregular astigmatism in the 3 and 5 mm central zones.

Unlike LASEK, LASIK significantly increases irregular astigmatism in the 3 and 5 mm central zones, according to Liliana Voinea and co-workers from the Optilaser Medical Center, Bucharest, Romania.

One hundred and three eyes undergoing LASIK (55 eyes) and LASEK (48 eyes) for myopia were evaluated. Corneal topography was performed preoperatively and six months following surgery. The Orbscan II videokeratoscope was used to obtain irregular astigmatism values in the 3 and 5 mm central zone.

Following LASIK, the researchers noted a statistically significant increase in the value of the irregular astigmatism in the 3 mm central zone (p=0.05, t=3.67) and 5 mm central zone (p=0.05, t=2.89). LASEK however, did not induce a statistically significant increase in these two parameters.

A direct correlation was also observed between the dioptric value of the myopia and the value of the irregular astigmatism following LASIK.

The researchers concluded that LASIK significantly increases the irregular astigmatism in the 3mm and 5 mm central zones.