Hammond B R, Nanez J E, Fair C, Snodderly D M
Department of Psychology, University of Georgia, Athens 30602-3013, USA.
Ophthalmic Physiol Opt. 2000 Sep;20(5):381-6.
Epidemiologic evidence indicates that dark iris color increases risk of age-related cataract. No information is currently available, however, on the effects of iris color on the lens prior to cataract development. In this study, we relate iris color to lens optical density (OD) in individuals without frank cataract.
90 subjects with blue or green irises (light color) were compared with 87 subjects having hazel, brown, or black irises (dark color). Lens OD was measured psychophysically by comparing scotopic thresholds obtained at 410 (measuring) and 550 nm (reference). Stimuli were presented in Maxwellian view.
The groups with light and with dark iris color did not differ significantly in smoking habits, dietary patterns, or age. Despite other similarities between the groups, lens OD was significantly (p < 0.024) higher in the group with dark irises. The higher OD of the dark iris group was due to differences in the older subjects (> 45 years, p < 0.005), rather than the younger subjects (20-45 years) who showed no differences in lens OD.
Our data indicate that iris pigmentation may be directly related to age-associated increases in lens OD.
流行病学证据表明，深色虹膜会增加年龄相关性白内障的风险。然而，目前尚无关于白内障发生前虹膜颜色对晶状体影响的信息。在本研究中，我们将无明显白内障个体的虹膜颜色与晶状体光学密度（OD）相关联。
将90名蓝或绿虹膜（浅色）受试者与87名淡褐色、棕色或黑色虹膜（深色）受试者进行比较。通过比较在410nm（测量）和550nm（参考）处获得的暗视阈值，以心理物理学方法测量晶状体OD。刺激以麦克斯韦观察法呈现。
浅色和深色虹膜组在吸烟习惯、饮食模式或年龄方面无显著差异。尽管两组之间存在其他相似之处，但深色虹膜组的晶状体OD显著更高（p<0.024）。深色虹膜组较高的OD是由于老年受试者（>45岁，p<0.005）存在差异，而年轻受试者（20 - 45岁）的晶状体OD无差异。
我们的数据表明虹膜色素沉着可能与年龄相关的晶状体OD增加直接相关。
