Curcio C A, Sloan K R, Kalina R E, Hendrickson A E
Department of Biological Structure, University of Washington, Seattle 98195.
J Comp Neurol. 1990 Feb 22;292(4):497-523. doi: 10.1002/cne.902920402.
We have measured the spatial density of cones and rods in eight whole-mounted human retinas, obtained from seven individuals between 27 and 44 years of age, and constructed maps of photoreceptor density and between-individual variability. The average human retina contains 4.6 million cones (4.08-5.29 million). Peak foveal cone density averages 199,000 cones/mm2 and is highly variable between individuals (100,000-324,000 cones/mm2). The point of highest density may be found in an area as large as 0.032 deg2. Cone density falls steeply with increasing eccentricity and is an order of magnitude lower 1 mm away from the foveal center. Superimposed on this gradient is a streak of high cone density along the horizontal meridian. At equivalent eccentricities, cone density is 40-45% higher in nasal compared to temporal retina and slightly higher in midperipheral inferior compared to superior retina. Cone density also increases slightly in far nasal retina. The average human retina contains 92 million rods (77.9-107.3 million). In the fovea, the average horizontal diameter of the rod-free zone is 0.350 mm (1.25 degrees). Foveal rod density increases most rapidly superiorly and least rapidly nasally. The highest rod densities are located along an elliptical ring at the eccentricity of the optic disk and extending into nasal retina with the point of highest density typically in superior retina (5/6 eyes). Rod densities decrease by 15-25% where the ring crosses the horizontal meridian. Rod density declines slowly from the rod ring to the far periphery and is highest in nasal and superior retina. Individual variability in photoreceptor density differs with retinal region and is similar for both cones and rods. Variability is highest near the fovea, reaches a minimum in the midperiphery, and then increases with eccentricity to the ora serrata. The total number of foveal cones is similar for eyes with widely varying peak cone density, consistent with the idea that the variability reflects differences in the lateral migration of photoreceptors during development. Two fellow eyes had cone and rod numbers within 8% and similar but not identical photoreceptor topography.
我们测量了8个完整的人类视网膜中视锥细胞和视杆细胞的空间密度，这些视网膜取自7名年龄在27至44岁之间的个体，并构建了光感受器密度图以及个体间差异图。人类视网膜平均含有460万个视锥细胞（408万至529万个）。中央凹视锥细胞密度峰值平均为199,000个/mm²，个体间差异很大（100,000至324,000个/mm²）。密度最高的点可能出现在面积达0.032度²的区域内。视锥细胞密度随着离心率增加而急剧下降，在距中央凹中心1毫米处降低一个数量级。叠加在这个梯度上的是沿着水平子午线的一条视锥细胞高密度带。在相同离心率下，鼻侧视网膜的视锥细胞密度比颞侧视网膜高40 - 45%，中周部下侧视网膜的视锥细胞密度比上侧视网膜略高。远鼻侧视网膜的视锥细胞密度也略有增加。人类视网膜平均含有9200万个视杆细胞（7790万至1.073亿个）。在中央凹，无杆细胞区的平均水平直径为0.350毫米（1.25度）。中央凹视杆细胞密度在上方增加最快，在鼻侧增加最慢。最高视杆细胞密度位于与视盘离心率相同的椭圆形环上，并延伸至鼻侧视网膜，密度最高的点通常在上侧视网膜（6只眼中有5只）。当环与水平子午线交叉时，视杆细胞密度降低15 - 25%。视杆细胞密度从视杆细胞环向远周边缓慢下降，在鼻侧和上侧视网膜中最高。光感受器密度的个体差异因视网膜区域而异，视锥细胞和视杆细胞的情况相似。差异在中央凹附近最高，在中周部达到最小值，然后随着离心率增加至锯齿缘而增大。峰值视锥细胞密度差异很大的眼睛，其中央凹视锥细胞总数相似，这与差异反映发育过程中光感受器横向迁移差异的观点一致。两只双眼的视锥细胞和视杆细胞数量相差8%以内，光感受器地形图相似但不完全相同。
