不同程度近视散光患者TransPRK术后功能性光学区的临床分析

Clinical analysis of functional optical zone after transepithelial photorefractive keratectomy in patients with different degrees of myopic astigmatism

摘要:

目的：评估术前近视散光大小及角膜前表面曲率对经上皮准分子激光角膜表面切削术(TransPRK)后功能性光学区(FOZ)的影响。方法：采用回顾性分析，选择近视及近视散光患者78例130眼应用TransPRK治疗，根据柱镜度不同分为：对照组，柱镜度0D； 中度散光组，柱镜度-0.50～-2.00D； 高度散光组，柱镜度>-2.00～<-6.00D。测量并比较术后6mo三组FOZ大小，分析拟矫屈光度、角膜前表面曲率变化、角膜像差变化、Q值变化与FOZ的相关性。结果：术后6mo，对照组平均FOZ为5.16±0.12mm，中度散光组为5.29±0.23mm，高度散光组为5.49±0.23mm(P<0.001)。高度散光组FOZ明显大于中度散光组和对照组(P<0.05，<0.001)； Pearson相关分析表明，等效球镜度变化量、角膜总高阶像差(HOAs)变化量、彗差变化量、球差变化量与FOZ均呈负相关(均P<0.05)； 陡峭曲率(K2)、平均曲率(Km)、角膜散光变化量、Q值变化量与FOZ均呈正相关(均P<0.01)。多元线性回归分析表明，在去除其他危险因素后，术前K2仍与FOZ呈正相关(P<0.001)。结论：高度散光患者在TransPRK后获得较大FOZ和引入较少彗差。术前陡峭曲率高近视散光眼将取得较大FOZ。

Abstract:

AIM: To evaluate the effect of preoperative degrees of myopic astigmatism and anterior corneal curvature on the functional optical zone(FOZ)after transepithelial photorefractive keratectomy(TransPRK).METHODS: Retrospective study was conducted on 78 patients(130 eyes)with myopia and myopic astigmatism who underwent TransPRK, and they were divided into control group(cylinder 0D), moderate astigmatism group(-0.50～-2.00D)and high astigmatism group(>-2.00～<-6.00D). The FOZ was measured and compared among the three groups 6mo after operation. The correlations between attempted correction, anterior corneal curvature, corneal aberrations, Q value, and the FOZ were analyzed.RESULTS: At 6mo after operation, the mean FOZ was 5.16±0.12mm in the control group, 5.29±0.23mm in the moderate astigmatism group, and 5.49±0.23mm in the high astigmatism group(P<0.001), and the FOZ of the high astigmatism group was significantly higher than moderate astigmatism and control group(P<0.05, P<0.001); Pearson correlation analysis showed that the changes in spherical equivalent, total corneal higher-order aberrations(HOAs), coma, and spherical aberration were all negatively correlated with FOZ(all P<0.05); and FOZ positively correlated with changes in the steep curvature(K2), mean curvature(Km), corneal astigmatism, and Q value(all P<0.01). Multiple linear regression analysis showed that there was still positive correlation between preoperative K2 and FOZ after adjusting for other risk factors(P<0.001).CONCLUSION: Patients with high astigmatism can obtain a larger FOZ and less induced coma after TransPRK. A larger FOZ can be achieved in eyes with steeper keratometry.