SMILE术后角膜前表面非球面性与角膜高阶像差的关系

目的探讨SMILE术后角膜前表面非球面性与角膜高阶像差变化特点及其相关性。方法前瞻性研究。随机选取自愿行SMILE手术的屈光不正患者41例，均选右眼为研究眼，于手术前及手术后3个月分别测量患者角膜前表面6、7、8、9mm直径范同的非球面系数Q值，并测量角膜总高阶像差（HOA）、球差（Z4^0）、次级球差（Z6^0）、垂直彗差（Z3^-1）、水平彗差（Z3^1）、水平三叶草（Z3^-3）、倾斜三叶卓（Z3^3）等高阶像差。采用配对t检验和Pearson相关进行数据分析。结果SMILE手术后角膜前表面6、7、8、9mm直径范围Q值均Fh负值转变为正值（t=-23．558、-26．661、-28．366、-28．788，P〈0．01）。角膜HOA、Z4^0、Z6^0、Z3^-1、Z3^1数值均增大（t=-11．815、-11．813、-16．209、6．470、4．835，P〈0．01），而Z3^-3、Z3^3与术前比较差异无统计学意义（t=0．278、-1．064，P〉0．05）。术前角膜HOA、Z4^0、Z3^-1与Q值有-定的相关性（P〈0．05），SMILE手术前后角膜HOA、Z4^0差值与角膜前表面各直径范同Q值差值均呈正相关关系（HOA：r=0．554、0．480、0．416、0．352，P〈0．05；Z40：r=0．671、0．577、0．495、0．395，P〈0．05）：Z3^-1差值与6、7mm直径范同Q值差值呈正相关（r=0．377、0．342，P〈0．05）；Z3^-1差值与6、7、8mm直径范同Q值差倩呈止相关（r=0．436、0．385、0．316，P〈0．05）；Z6^0、Z3^-3、Z3^3差值与各直径范同Q值差值均无相关性。透镜直径与SMILE手术前后Q值差值无相关性；与角膜HOA、Z4^0差值呈负相关（r=-0．315．-0．393，P〈0．05）；与角膜Z6^0、Z3^-1、Z3^-1、Z3^-1、Z3^3差值均无相关性（P〉O．05）。结论SMILE手术后角膜前表面O值由负值转变为止佰；角膜高阶像差增大；透镜直径越大，角膜HOA、Z4^0变化越小。角膜前表面Q值与角膜HOA、Z4^0、Z3^-1、Z3^1变化量均有正相关关系，其中与Z4^0相关程度最强?

The correlation between corneal asphericity and higher order aberrations after SMILE surgery

Objective To evaluate the characteristics of anterior corneal asphericity and higher order aberrations after SMILE surgery, and to analyze the correlation between them. Methods In this prospective study, 41 subjects who underwent SMILE surgery were enrolled with right eyes selected for the study. The aspherieity coefficient Q-value at diameters of 6, 7, 8 and 9 mm and total higher order aberrations （HOA）, spherical aben＇ations （Z4^0）, secondary spherical aberrations 1 （Z6^0）, vertieal coma （Z3^-1）, horizontal coma （Z3^1）, y-trefoil （Z3^-3） and x-trefoil （Z3^3） of the cornea were measured before surgery and 3 months following the surgery. A paired-samples t test and Pearson correlation were used for analysis. Results All Q-values increased from negative to positive after SMILE surgery and the differences were statistically significant （t=-23.558, -26.661, -28.366, -28.788, P〈0.01）. Corneal HOA, Z4^0, Z6^0, Z3^-1 and Z3^1 increased and the differences were statistically significant as well （t=-11.815, -11.813, -16.209, 6.470, 4.835, P〈0.01）. However, the change in Z3^-3 or Z3^3 was not signifieant （t=0.278, -1.064, P〉0.05）. Among corneal higher order aberrations, a linearcorrelation was found between the Q-value and corneal HOA, Z4^0 and Z3^-1 before surgery （P〈0.05）. The change in corneal HOA and Z4^0 had a positive linear correlation with the Q-value at each diameter （HOA： r=0.554, 0.480, 0.416, 0.352, P〈0.05; Z4^0： r=0.671, 0.577, 0.495, 0.395, P〈0.05）. The difference in Z3^-1 had a positive linear correlation with the Q-values at diameters 6 and 7 mm （r=0.377, 0.342, P〈0.05）. The difference in Z31 had a positive linear correlation with the Q-values at diameters 6, 7 and 8 mm （r=0.436, 0.385, 0.316, P〈0.05）. No linear correlation was found between the changes in the Q-values at each diameter and those of Z3^-3, Z3^3 or Z6^0 （P〉0.05）. There was not a linear correlation between the change in the Q-values and lens diameter （P〉0