Department of Ophthalmology, Shanghai Sixth People's Hospital, Shanghai Jiaotong University, 600 Yishan Road, Shanghai, 200233, People's Republic of China.
BMC Ophthalmol. 2012 Jun 18;12:15. doi: 10.1186/1471-2415-12-15.
To compare the corneal high-order aberrations (HOAs), asphericity and regularity after Q-value guided laser in situ keratomileusis (LASIK) and laser epithelial keratomileusis (LASEK) in high myopic astigmatism.
In this retrospectively comparative study, we measured the corneal HOAs, asphericity indices (Q values) and corneal regularity indices preoperatively and 36 months postoperatively in 70 eyes (35 patients) with Q-value guided surgeries. All the patients with high myopic astigmatism were divided into two groups which included 34 eyes underwent LASIK and 36 eyes underwent LASEK procedures. The main impact factors of the high-order aberrations were also analyzed.
In the two groups, the efficacy index was more than 1.00 and safety index approached 1.00 at year 3 postoperatively. Statistically significant (P < 0.05) increased in Q values and main corneal HOAs (spherical aberrations and coma) following Q-value guided LASIK and LASEK procedures. Spherical aberrations increased more in the LASEK group and there was statistically difference compared to the LASIK group (P < 0.05). LASEK had better effects in correcting corneal astigmatism (P < 0.05). All the corneal regularity indices after surgeries increased and there was no significant difference (P = 0.707, P = 0.8 and P = 0.224, respectively) between the two groups. The main impact factors of spherical aberration included the optic zone size, changes of Q value, surgical procedure and the corrected refraction.
In high myopic astigmatism, Q-value guided ablation showed good safety, efficacy and predictability. Q value, regularity indices, spherical aberration and coma increased in both LASIK and LASEK procedures. Astigmatism could be corrected more effectively by LASEK but greater spherical aberration could be created. The difference might be related to the different healing mechanisms. Optic zone size and the corrected refraction might be the main influence factors on the anterior corneal high order aberrations.
比较 Q 值引导的准分子激光原位角膜磨镶术(LASIK)和激光上皮下角膜磨镶术(LASEK)治疗高度近视散光患者的角膜高阶像差(HOAs)、非球面性和规则性。
在这项回顾性对照研究中,我们测量了 70 只眼(35 例)术前和术后 36 个月 Q 值引导手术后的角膜高阶像差、非球面性指数(Q 值)和角膜规则性指数。所有高度近视散光患者分为两组,其中 34 只眼行 LASIK,36 只眼行 LASEK。还分析了高阶像差的主要影响因素。
两组术后 3 年的疗效指数均大于 1.00,安全性指数接近 1.00。Q 值引导的 LASIK 和 LASEK 术后 Q 值和主要角膜高阶像差(球差和彗差)均显著增加(P<0.05)。LASEK 组的球差增加较多,与 LASIK 组相比差异有统计学意义(P<0.05)。LASEK 矫正角膜散光的效果更好(P<0.05)。术后所有角膜规则性指数均增加,差异无统计学意义(P=0.707,P=0.8,P=0.224)。球差的主要影响因素包括光区大小、Q 值变化、手术方式和矫正屈光。
在高度近视散光中,Q 值引导消融具有良好的安全性、有效性和可预测性。LASIK 和 LASEK 术后 Q 值、规则性指数、球差和彗差均增加。LASEK 可更有效地矫正散光,但可能产生更大的球差。这种差异可能与不同的愈合机制有关。光区大小和矫正屈光可能是角膜前表面高阶像差的主要影响因素。