Age-related accumulation and spatial distribution of lipofuscin in RPE of normal subjects.
Age-related accumulation and spatial distribution of lipofuscin in RPE of normal subjects.
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DOI：
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发表时间：
2001-07
影响因子：
4.4
通讯作者：
F. Delori;D. Goger;C. Dorey
中科院分区：
文献类型：
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作者：
F. Delori;D. Goger;C. Dorey
目的描述正常人群中与年龄相关的脂褐素积累，解决以往研究中获得的估计积累率的差异，并描述脂褐素在正常眼底的空间分布。方法对145例正常人（年龄15-80岁）的黄斑中心凹及颞侧7 °进行分光光度测量。空间分布沿着四个主要经络测定在选定的主题分光光度法和自体荧光成像。为了最小化外来荧光团、黄斑色素和黑色素的贡献，所有测量都使用550 nm处的激发，在650和750 nm之间积分发射。结果脂褐素荧光强度在70岁以前呈线性增加，然后下降。在中央凹中的蓄积速率显著低于颞叶部位;体内蓄积速率大于先前在显微镜研究中观察到的蓄积速率。荧光在中央凹中比在7度偏心率下低约40%，并且在中央凹周围不对称地分布。荧光在颞侧约11度、鼻侧约7度、上方约13度和后方约9度处最大。在相同的偏心率下，荧光总是沿着下子午线比沿着任何其他子午线少。结论：RPE黑色素的光吸收可以解释体内和离体估计的脂褐素积累速率之间的差异。老年时荧光下降可能代表萎缩的RPE细胞的去除。脂褐素的空间分布通常与视杆细胞的空间分布相匹配，反映而不是预测视杆细胞光感受器的年龄相关损失的模式。
PURPOSE To characterize the age-related accumulation of lipofuscin in a population of normal subjects, resolve differences in estimated accumulation rates obtained in previous studies, and characterize the spatial distribution of lipofuscin in the normal fundus. METHODS Spectrophotometric measurements were made at the fovea and 7 degrees temporal to the fovea in 145 normal subjects (age range, 15-80 years). Spatial distribution along the four cardinal meridians was measured in selected subjects by both spectrophotometry and autofluorescence imaging. To minimize contributions of extraneous fluorophores, macular pigment, and melanin, all measurements used excitation at 550 nm, integrating emission between 650 and 750 nm. RESULTS Lipofuscin fluorescence increased linearly until age 70, then declined. The rate of accumulation was significantly slower in the fovea than at the temporal site; accumulation rates in vivo were greater than previously observed in microscopic studies. Fluorescence was approximately 40% lower in the fovea than at 7 degrees eccentricity and was asymmetrically distributed around the fovea. The fluorescence was maximal at approximately 11 degrees temporally, approximately 7 degrees nasally, approximately 13 degrees superiorly, and approximately 9 degrees inferiorly. At the same eccentricity, fluorescence was always less along the inferior meridian than along any other. CONCLUSIONS Light absorption by RPE melanin can explain differences between the in vivo and ex vivo estimates of the rate of lipofuscin accumulation. Declining fluorescence at old age may represent removal of atrophic RPE cells. The spatial distribution of lipofuscin generally matches that of rods and reflects, rather than predicts, the pattern of age-related loss of rod photoreceptors.