非球面IOL波前像差及对视觉质量影响研究

发布时间：2018-06-23 02:21

本文选题：晶状体 + 人工　；参考：《天津医科大学》2010年博士论文

【摘要】： 目的： 1研究偏心对非球面人工晶状体(Intraocular lens, IOL)与传统球面IOL的像差光学特性影响； 2探讨基于Liou-Brennan眼模型的球面和非球面IOL表观调节； 3根据不同患者眼部解剖参数建立个体化眼模型,研究植入不同设计的IOL的光学表现。方法： 1搭建IOL像差测量光路,Hartmann-Shack像差仪测量像差。在3mm和5mm通光孔径下,分别测量Tecnis Z9000, FY60AD, SN60WF, YA60BBR 4种IOL居中及水平偏心0.2mm、0.4mm、0.6mm、0.8mm、1.0mm时像差。 2利用ZEMAX光学设计软件建立Liou-Brennan眼模型,用不同IOL(LI61AO, Tecnis Z9000, FY60AD, Cee On911, SA60AT, YA60BBR及P359UV)光学参数分别替代自然晶状体,模拟IOL眼光学系统。(1)采用光线追迹原理,分析IOL前移时眼睛光学系统离焦量变化,计算调节力改变。(2)模拟550nm单色光、6cycles/degree/degree空间频率下不同IOL眼光学系统离焦调制传递函数曲线,分析其焦深。 3使用Pentacam眼前节三维分析诊断系统和IOL Master获取超声乳化白内障摘除IOL植入术后3个月患者眼前节结构和眼轴长度参数,输入ZEMAX构建个体化眼结构模型。在以上个体化眼模型中分别植入SofPort AO、Tecnis Z9000、FY60AD、YA60BBR 4种IOL,模拟3～5mm瞳孔直径、550nm工作波长下,个体化IOL眼模型眼对无穷远点成像时的MTF及CSF。结果： 1 3mm瞳孔下随着偏心程度的增加,IOL总像差、3阶慧差RMS增加,4个IOL均具有统计差异(P0.01)。球面IOL偏心时球差改变无统计学差异(P0.05)；3个非球面IOL球差随偏心程度增加上升,差异有统计学意义(P0.05)；将IOL不同程度偏心与居中时球差比较,非球面IOL偏心达到或超过0.8mm时差异有统计学意义(P0.05)。 2 5mm通光口径下,随偏心程度增加IOL总体像差和慧差RMS上升,差异具有统计学意义(P0.01)。球面IOL球差随偏心程度增加略有上升,无统计学差异(P0.05)；3个非球面IOL球差随偏心程度增加上升,差异有统计学意义(P0.05)；将IOL偏心与居中时球差比较,非球面IOL偏心达到或超过0.8mm时差异出现统计学意义(P0.05)。 3 IOL在眼内位置前移可使眼睛屈光力增强,球面和非球面IOL眼屈光力改变与位移距离均呈线性关系,前者略大于后者。 4球面和非球面IOL焦深均随瞳孔直径缩小而增加,球面IOL对负离焦耐受好与非球面IOL,瞳孔直径较大时明显。 5 3mm瞳孔下,个体化眼模型中3种非球面IOL和1种球面IOL的MTF和CSF接近。 6 5mm瞳孔下,个体化眼模型植入4种IOL后MTF和CSF曲线差异明显,不同解剖参数个体获得最佳MTF和CSF的IOL种类不同。结论： 1 IOL偏心引起总体像差和3阶慧差RMS显著增加,球面IOL YA60BBR四阶对称性球差保持稳定,非球面IOL Tecnis Z9000、FY60AD、SN60WF四阶对称性球差几乎保持稳定。偏心引起的慧差等不对称像差增加是造成IOL像质下降的主要原因。 2非球面IOL在眼内前移引起的调节增加量略小于球面IOL。非球面IOL的负球差与角膜正球差中和,全眼球差下降,在良好聚焦时其MTF高于球面IOL,但随着离焦增加MTF迅速下降,在某种程度上损失了焦深,使非球面IOL眼对离焦的耐受能力下降。 3根据人眼解剖参数建立个体化眼模型可以模拟该个体眼睛光学系统的光学质量。使不同解剖结构的人眼光学系统获得最佳视觉质量的IOL种类不同。
[Abstract]:Purpose :

1 To study the influence of eccentricity on aberration optical characteristics of aspheric intraocular lens ( IOL ) and traditional spherical IOL ;

2 . The apparent regulation of spherical and aspheric IOLs based on the Liou - brennan eye model was discussed .

3 Individual eye model was established according to different patient ' s ocular anatomy parameters , and the optical performance of IOL implanted with different design was studied .

Method :

1 An IOL aberration measuring optical path was built . The aberration of aberration was measured by the har. The aberration of Tecnis Z9000 , FY60AD , SN60WF , YA60BBR was measured at 3mm and 5mm . The center and the horizontal eccentricity of the four IOLs were 0.2mm , 0.4mm , 0.6mm , 0.8mm and 1.0 mm respectively .

( 1 ) The focal depth of the IOL ' s eye optical system was analyzed by simulating 550 nm single color light , 6 cycles / degree / degree spatial frequency , and the focal depth was analyzed by using the principle of ray tracing and ( 2 ) simulating the defocus amount of the optical system of different IOL ' s eyes at 550 nm single color light , 6 cycles / degree / degree spatial frequency .

3 Three - month anterior segment structure and ocular axial length parameters were obtained by using the Pentacam anterior segment 3D analysis and diagnosis system and IOL Master . In the above individualized eye model , we implanted SofPort AO , Tecnis Z9000 , FY60AD , YA60BBR four IOLs , simulated the MTF and CSF at infinity point of the individualized IOL ' s eye model at the wavelength of 3 ~ 5mm pupil and 550 nm working wavelength .

Results :

With the increase of eccentricity , the total aberration of IOL , third - order coma RMS and 4 IOLs were statistically different ( P0.01 ) , and the spherical aberration changed without statistical difference ( P0.05 ) .
The spherical aberration of three aspheric IOL increased with increasing eccentricity ( P0.05 ) .
The difference was statistically significant ( P0.05 ) when the eccentricity of IOL was more than 0.8 mm .

The spherical IOL spherical aberration increased slightly with the eccentricity and no statistical difference ( P0.05 ) .
The spherical aberration of three aspheric IOL increased with increasing eccentricity ( P0.05 ) .
The difference between IOL eccentricity and spherical aberration was statistically significant when the eccentricity of the aspheric IOL reached or exceeded 0.8mm ( P0.05 ) .

The anterior movement of IOL in the intraocular location could enhance the refractive power of the eye , the change of the refractive power of the spherical and aspheric IOL and the displacement distance , the former being slightly larger than the latter .

The focal depth of both spherical and aspherical IOL increased with the reduction of pupil diameter .

The MTF and CSF of three non - spherical IOLs and one spherical IOL were close in the individual eye model under a 5 mm pupil .

The MTF and CSF curves of the individual eye model were significantly different after implantation of 4 IOLs under the pupil of 6 mm , and the IOL types of the individual optimal MTF and CSF were different among different anatomic parameters .

Conclusion :

The aberration of spherical IOL YA60BBR was stable , the spherical IOL Tecnis Z9000 , FY60AD and SN60WF were almost stable . The asymmetry aberration caused by eccentricity was the main reason for the decrease of IOL image quality .

The aspheric IOL is slightly smaller than that of the spherical IOL . The negative spherical aberration of the aspheric IOL is less than that of the spherical IOL . The MTF of the aspheric IOL is higher than that of the spherical IOL at the time of good focusing , but the focal depth is lost to some extent as the defocus increases , and the tolerance of the aspheric IOL ' s eye to the defocus is reduced .

3 , the optical quality of the individual ' s eye optical system can be simulated according to the human eye anatomical parameters .
【学位授予单位】：天津医科大学
【学位级别】：博士
【学位授予年份】：2010
【分类号】：R77

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