State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
Clin Exp Ophthalmol. 2012 Mar;40(2):162-9. doi: 10.1111/j.1442-9071.2011.02658.x. Epub 2011 Sep 28.
To assess the distribution of iris structural measurements among American Caucasians, American Chinese and mainland Chinese aged 40years and over, in order to determine associated factors of increased risk for angle closure in Chinese.
Prospective multicentre cross-sectional study.
Four gender- and age-matched cohorts: Caucasians, American Chinese, Southern Chinese from Guangzhou and Northern Chinese from Beijing were enrolled in this study.
Anterior segment optical coherence tomography was utilized to image the anterior chamber. Customized software was used to calculate the related parameters from anterior segment optical coherence tomography images.
Iris thickness at 750µm from the scleral spur, iris curvature, iris area, pupil diameter.
Data from 121, 124, 121 and 120 subjects were available for American Caucasian, American Chinese, Southern and Northern Mainland Chinese subjects, respectively. The Chinese cohorts did not differ with regard to any of the parameters. Multiple linear regressions indicated that Caucasians had thinner iris thickness at 750µm from the scleral spur and smaller iris area than Chinese after controlling for potential confounders. Female Caucasians had thinner irides (P=0.015) and smaller iris area (P=0.001) than male Caucasians. Female Chinese tended to have more convex irides (P=0.021) than male Chinese. Pupil size was inversely associated with age (P<0.001) in both ethnicities.
In dark conditions, Chinese have thicker irides and greater iris area than Caucasians independent of pupil size. Among Chinese, more convex irides in women may account for the higher rate of narrow angles identified in this segment of the Chinese population.
评估 40 岁及以上的美国白种人、美籍华人以及中国大陆人群的虹膜结构测量值的分布情况，以确定中国人发生房角关闭风险增加的相关因素。
前瞻性多中心横断面研究。
本研究纳入了 4 个性别和年龄匹配的队列：白种人、美籍华人、来自广州的南方中国人和来自北京的北方中国人。
使用眼前节光学相干断层扫描仪对眼前节进行成像。使用定制软件从眼前节光学相干断层扫描仪图像中计算相关参数。
巩膜突 750µm 处的虹膜厚度、虹膜曲率、虹膜面积、瞳孔直径。
白种人、美籍华人、南方中国人和北方中国人的有效数据分别为 121、124、121 和 120 例。中国人的各个队列之间在任何参数上均无差异。多元线性回归表明，在控制了潜在混杂因素后，白种人巩膜突 750µm 处的虹膜厚度和虹膜面积比中国人更薄。女性白种人的虹膜更薄（P=0.015），虹膜面积更小（P=0.001）。与男性白种人相比，女性白种人的虹膜更凸（P=0.021）。瞳孔大小与年龄呈负相关（P<0.001），在这两个种族中均如此。
在暗光条件下，中国人的虹膜比白种人更厚，虹膜面积也更大，这与瞳孔大小无关。在中国人中，女性的虹膜更凸可能是导致该人群中这部分人出现窄角的比率较高的原因。
