Linear Correction Of Ultra-high Myopia In The Epi-lasik, Rotary Long-term Clinical Study

Objective:To investigate the safety,efficiency,predictability and stability of the correction of super-high myopia with Epi-LASIK;to investigate the long term visual quality and to investigate of contribution of the way of flap-making.Method:53 super-high myopic eyes of 31 patients corrected with Epi-LASIK 3 years ago were followed。Linear group,20 eyes of 12 patients, pre-operational refraction was -13.10±3.67D on average,BCVA log MAR was 0.04±0.09。Rotational group,33 eyes of 19 patients,pre-operational refraction was-13.10±2.23D on average,BCVA log MAR was 0.05±0.11.All cases were followed 1 mon,3 mon and 3 years post-operation.The routine examination included UCVA,refraction,BCVA,wavefront aberration,contrast sensitivity and glear sensitivity.Shack-Hartmann aberrometer(WFA-1000,Carl Zeiss) was used to measure the overall wavefront aberrations in scotopic pupils and the data was analyzed in 5mm diameter.TAKAGI CGT-1000 was used to measure the contrast sensitivity and glear sensitivity after the correction of refractive errors.SPSS15.0 was used to analyze the data of pre-operation,1 mon,3 mon and 3 years post-operation.Results:Refraction of the linear group 3 years post-operation was -3.46±2.80 D on average and BCVA log MAR was 0.04±0.10,which was not statistically significant.Refraction of the rotational group 3 years post-operation was -2.96±2.05D on average and BCVA log MAR was 0.00±0.07,which was statistically significant.The difference between groups was not statistically significant.The high order aberration post-operation was significantly increased,mainly displaying on RMS3 and RMS4.The differences between groups of RMSh,RMS3,RMS4 or RMS5 was not statistically significant.In the linear group,Z(3,-1) and Z(5, -1)were increased,while Z(3,+1) and Z(5,+1)were not.In the rotational group,Z(3,+1) and Z(5,+1) were increased,while Z(3,-1) and Z (5,-1) were not.The contrast sensitivity and glear sensitivity were decreased.No significant difference was found between groups. Conclusions:The correction of super-high myopia with Epi-LASIK was safe,efficient,predictable and stable.The high order aberrations increased mainly on spherical aberration.The contrast sensitivity and glear sensitivity were decreased.Linear or rotational flap-making had clinical outcomes.But it is to be discussed about the impact on coma.