角膜宁滴眼液治疗超声乳化白内障摘出术后角膜上皮损伤

目的观察角膜宁滴眼液对超声乳化白内障摘出术后角膜上皮损伤的治疗效果。方法随机将42例超声乳化白内障术后出现角膜上皮损伤患者分为两组,一组常规术后用药,一组加用角膜宁滴眼液,观察两组患者症状的改善和角膜上皮修复情况。结果加用角膜宁滴眼液组症状轻,角膜上皮修复快。结论给超声乳化术后角膜损伤患者加用角膜宁滴眼液,可改善症状,促进角膜上皮愈合。     

Agreement and reliability in measuring central corneal thickness with a rotating Scheimpflug–Placido system and ultrasound pachymetry

PurposeWe compare the agreement and the reliability in measuring central corneal thickness (CCT) using two different technologies.MethodThe right eyes of 35 healthy individuals who had a negative history of ophthalmic disease, or ocular surgery were examined. The CCT was determined sequentially with a rotating Scheimpflug camera (Sirius; CSO), and an ultrasound pachymeter (P-1; Takagi). For statistical analysis, we used the methods suggested by Bland and Altman.ResultsThe mean values of CCT obtained from Sirius, and ultrasound were 537 ± 28 μm, and 550 ± 35 μm, respectively. There was a high correlation between Sirius and ultrasound (r = 0.92; p < 0.001), but the difference between the two measurements was statistically significant (t = −5.7; p < 0.00001). The precision of Sirius and ultrasound were 9.4 and 15.9 μm; repeatability 13.3 and 22.4 μm, and coefficient of variation 0.9% and 1.5%, respectively. The intraclass correlation coefficient was 0.97 for Sirius and 0.95 for ultrasound.ConclusionsThe average difference between corneal thickness measured with Sirius and ultrasound pachymetry was small but clinically significant. This means that the two instruments cannot be used interchangeably. Sirius showed precision and repeatability almost twice as much as ultrasound pachymetry. Confidence interval of 13.3 μm for Sirius can show variations in corneal thickness with an uncertainty value lower than 2.5% in 95% of cases. The simplicity of use, the possibility to obtain pachymetric maps, and less invasiveness make this instrument potentially useful in contact lens practice.     

Moria-M2自动旋切式显微角膜板层刀在激光辅助原位角膜磨镶术中的临床应用

目的探讨Moria-M2自动旋切式显微角膜板层刀在用激光辅助原位角膜磨镶术(LASIK)治疗近视中的安全性和操作特点。方法采用法国Moria-M2自动旋切式显微角膜板层刀为558例、1 104只眼行准分子LASIK患者制作角膜瓣。刀头选择110(130μm)或130(160μm)厚的固定板层刀头;根据中央角膜曲率选负压吸引环(中央角膜曲率K值小于42D选-1 环,42-43D选0环,43-45D选+1环,45-47D选+2环);负压吸引环上的停止器档位选择7．5或8。结果作瓣过程中无卡刀、中途停顿及停停走走现象,角膜瓣边缘整齐,无锯齿样改变,角膜基质床光滑。术中并发症有“纽扣”瓣,发生率为 0．27％;游离瓣,发生率为0．09％;角膜瓣下基质床出现“岛屿现象”,即在基质床有不规则隆起,发生率为0．36％;走空刀发生率为0．09％;角膜瓣周边渗血发生率为0．45％;小角膜瓣发生率为0．09％。术中不良角膜瓣的发生率为0．815％。结论法国Moria-M2自动旋切式显微角膜板层刀安装方便,按角膜曲率选择负压吸引环及止刀器档位,制作角膜瓣效果好,无严重并发症,该刀安全性,稳定性好,值得临床推广应用。     

基于人眼光学模型的角膜模型的研究

位于眼球最前端的角膜是人眼光学系统的主要屈光元件之一,建立角膜模型具有重要的研究和临床意义。基于角膜面型的非球面特性,应用光学设计软件Zemax,从光学成像角度,提出了结合人眼光学模型的角膜双二次曲面模型的建立,并结合国人正视眼和近视眼的有关实测数据和分析结果,以人眼的波像差为评价函数,通过对初始模型眼的优化,给出了符合我国人眼特点的正视眼和近视眼模型中的角膜模型,讨论了矫正近视的矫正眼模型中的角膜理想模型和可用于角膜屈光手术中的切削模型。基于人眼光学模型的角膜双二次曲面模型也可为波像差引导的个性化角膜切削方案提供一个更适于实际应用的数字化模型。     

飞点扫描式准分子激光角膜屈光矫正系统

近年来新型的小光斑高速飞点扫描准分子激光系统以其具有的治疗时间短、矫正精度高、角膜切削表面极其光滑、易于集成波前像差技术实现"个体化切削"方案等优点,成为眼科激光手术的研究热点.本文从理论基础、光学系统等方面综述了国内第一台具有自主知识产权的飞点扫描式激光系统,此系统在临床动物实验和盲眼实验中取得了非常好的效果.