Winn B, Pugh J R, Gilmartin B, Owens H
Department of Vision Sciences, Aston University, Birmingham, UK.
Curr Eye Res. 1990 Oct;9(10):971-5. doi: 10.3109/02713689009069933.
Rapid and continuous fluctuations in ocular focus are known to occur when the eye views a stationary target. The advent of high-speed infra-red optometers has established that these microfluctuations of ocular accommodation have two dominant components: low frequency of less than 0.6 Hz and high frequency between 1.0-2.3Hz. Although the retinal image blur associated with microfluctuations has the potential to guide and maintain optimum accommodation levels, there is no consensus with regard to the respective contribution of each of the dominant frequency components. Using a newly-designed measurement and recording system we show that, when viewing a stationary target located at 25cm, individuals exhibit little variation in the frequency of low frequency components but significant variation in high frequency components. Simultaneous measurements of ocular accommodation and systemic arterial pulse demonstrate that the variation in high frequency component is significantly correlated with arterial pulse frequency. Since control experiments indicate that the microfluctuations are derived from activity of the crystalline lens our observations could provide the basis for a non-invasive method of assessing the effects of arterial pulse on ciliary body/choroidal vasculature, the vitreous/lens interface and intraocular pressure. Further, it is feasible that under certain conditions an abnormal increase in the magnitude of arterial pulse may affect the aggregate nature of accommodative microfluctuations to an extent that disrupts the normal control processes maintaining optimum retinal contrast during sustained near vision.
当眼睛注视静止目标时，已知会出现快速且持续的眼聚焦波动。高速红外验光仪的出现证实，这些眼调节的微波动有两个主要成分：频率低于0.6Hz的低频成分和频率在1.0 - 2.3Hz之间的高频成分。尽管与微波动相关的视网膜图像模糊有可能引导和维持最佳调节水平，但关于每个主要频率成分各自的贡献尚无共识。使用新设计的测量和记录系统，我们发现，当注视位于25cm处的静止目标时，个体低频成分的频率变化很小，但高频成分有显著变化。眼调节与全身动脉脉搏的同步测量表明，高频成分的变化与动脉脉搏频率显著相关。由于对照实验表明微波动源自晶状体的活动，我们的观察结果可为一种非侵入性方法提供基础，该方法用于评估动脉脉搏对睫状体/脉络膜血管系统、玻璃体/晶状体界面及眼内压的影响。此外，在某些情况下，动脉脉搏幅度的异常增加可能会在一定程度上影响调节微波动的总体性质，从而扰乱在持续近视力期间维持最佳视网膜对比度的正常控制过程，这是可行的。
