Knighton R W, Jacobson S G, Kemp C M
Bascom Palmer Eye Institute, Department of Ophthalmology University of Miami School of Medicine, Florida 33101.
Invest Ophthalmol Vis Sci. 1989 Nov;30(11):2392-402.
This paper reports the first quantitative measurements of the reflectance spectrum of the nerve fiber layer (NFL) of the retina. An arcuate defect in the NFL of two macaque monkeys was produced by photocoagulating a small spot near the optic disc. Imaging fundus reflectometry at 8 wavelengths was then used to measure the fundal reflectances in the defect and in the intact NFL. The reflectance of the NFL alone was determined by subtracting the reflectance of the bare fundus in the defect from the reflectance of the adjoining fundus with intact NFL. The reflectance data were corrected for the transmission of the ocular media with published values of the density of monkey cornea and lens. Lens absorption was measured from Purkinje images and differed little from the published values. The NFL reflectance can be characterized by a spectrum that has the same shape at all points along an arcuate region of the NFL but decreases in absolute reflectance as the thickness of the NFL decreases. The reflectance changes little between 680 and 560 nm, but rises as lambda-n from 560 to 460 nm, where n = 2.5-3.1. The data reported here begin to provide a quantitative understanding of empirically determined methods for enhancing the visibility of the NFL and have implications for retinal densitometry.
本文报道了对视网膜神经纤维层（NFL）反射光谱的首次定量测量。通过对两只猕猴视盘附近的一个小点进行光凝，在其NFL中产生了一个弧形缺损。然后使用8波长的眼底反射成像法测量缺损处和完整NFL处的眼底反射率。仅NFL的反射率是通过用相邻完整NFL眼底的反射率减去缺损处裸眼底的反射率来确定的。利用已发表的猴角膜和晶状体密度值对反射率数据进行了眼内介质透过率的校正。从普尔钦耶图像测量晶状体吸收率，其与发表值相差不大。NFL反射率可以用一种光谱来表征，该光谱在NFL的一个弧形区域的所有点上具有相同的形状，但随着NFL厚度的减小，绝对反射率会降低。在680至560纳米之间反射率变化不大，但从560至460纳米随着λ - n上升，其中n = 2.5 - 3.1。此处报道的数据开始为增强NFL可见性的经验确定方法提供定量理解，并对视网膜密度测定有影响。
