Morgan Jessica I W, Hunter Jennifer J, Masella Benjamin, Wolfe Robert, Gray Daniel C, Merigan William H, Delori François C, Williams David R
Center for Visual Science, University of Rochester, Rochester, New York 14627, USA.
Invest Ophthalmol Vis Sci. 2008 Aug;49(8):3715-29. doi: 10.1167/iovs.07-1430. Epub 2008 Apr 11.
Autofluorescence fundus imaging using an adaptive optics scanning laser ophthalmoscope (AOSLO) allows for imaging of individual retinal pigment epithelial (RPE) cells in vivo. In this study, the potential of retinal damage was investigated by using radiant exposure levels that are 2 to 150 times those used for routine imaging.
Macaque retinas were imaged in vivo with a fluorescence AOSLO. The retina was exposed to 568- or 830-nm light for 15 minutes at various intensities over a square (1/2) degrees per side. Pre- and immediate postexposure images of the photoreceptors and RPE cells were taken over a 2 degrees field. Long-term AOSLO imaging was performed intermittently from 5 to 165 days after exposure. Exposures delivered over a uniform field were also investigated.
Exposures to 568-nm light caused an immediate decrease in autofluorescence of RPE cells. Follow-up imaging revealed either full recovery of autofluorescence or long-term damage in the RPE cells at the exposure. The outcomes of AOSLO exposures and uniform field exposures of equal average power were not significantly different. No effects from 830-nm exposures were observed.
The study revealed a novel change in RPE autofluorescence induced by 568-nm light exposure. Retinal damage occurred as a direct result of total average power, independent of the light-delivery
Because the exposures were near or below permissible levels in laser safety standards, these results suggest that caution should be used with exposure of the retina to visible light and that the safety standards should be re-evaluated for these exposure conditions.
使用自适应光学扫描激光检眼镜（AOSLO）进行自体荧光眼底成像可在体内对单个视网膜色素上皮（RPE）细胞进行成像。在本研究中，通过使用比常规成像高2至150倍的辐射暴露水平来研究视网膜损伤的可能性。
用荧光AOSLO对猕猴视网膜进行体内成像。视网膜以每边（1/2）度的正方形在不同强度下暴露于568或830纳米的光下15分钟。在2度视野范围内拍摄光感受器和RPE细胞的暴露前和暴露后即刻图像。暴露后5至165天间歇性地进行长期AOSLO成像。还研究了在均匀视野上的暴露情况。
暴露于568纳米光导致RPE细胞的自体荧光立即降低。后续成像显示，暴露处的RPE细胞自体荧光要么完全恢复，要么出现长期损伤。平均功率相等的AOSLO暴露和均匀视野暴露的结果没有显著差异。未观察到830纳米暴露的影响。
该研究揭示了568纳米光暴露引起的RPE自体荧光的一种新变化。视网膜损伤是总平均功率的直接结果，与光的传输方式无关。
由于这些暴露接近或低于激光安全标准中的允许水平，这些结果表明，在视网膜暴露于可见光时应谨慎，并且应对这些暴露条件下的安全标准进行重新评估。
