Mesopic contrast sensitivity before and after LASIK surgery for myopes

Objective To evaluate the night visual quality changes between the low or moderate myopgs and the high myopes under mesopic condition before and after LASIK surgery.Methods Randomly selected 38 low or moderate myopes and 38 high myopes.All the patients were treated under the regular LASIK standards.Mesotest II b was used to examine the mesopic contrast sensitivity function at the point of pre-operafion,1 month and 3 months post-operation.Preoperative and postoperative parameters in and between the two groups were compared.Results The mesopic contrast sensitivity function of the high myopes group were worse than that of the low or moderate myopes group both before and after surgery(P ＜ 0.05).The self-contrast in two group showed that while there was a significant difference in mesopic contrast sensitivity function between pro-and post-operation in the high myopes,no significant difference was found in the low or moderate myopes.Conclusions The night visual quality of the low or moderate myopes is better than that of the high myopes both before and after LASIK surgery. Key words: Laser in situ kcratomileusis; Visual quality; Night vision disturbunce,Mesopic contrastsensitivity function