ASTIGMATISM AND AMBLYOPIA AMONG NATIVE AMERICAN CHILDREN

美洲原住民散光程度高 人民。虽然散光的流行率已经得到了很好的研究， 它的发展过程和视觉后果很差 明白了。拟议研究的目标是建立 散光与视力发育的关系 美洲原住民儿童，并确定最佳 减少散光的有害影响的策略 人口。提出了一种三态研究协议： 阶段1：角膜、内角膜和全角膜的患病率 散光(以及视力下降和 将对学龄前儿童进行子午线弱视检查 6个月至6岁以上的土著家庭成员 美国部落(Tohono O‘Odham Nation)，在这个部落中 散光普遍存在。 阶段2：将根据以下条件提供眼镜校正 对334名儿童眼科护理的民意调查得出的指导方针 从业者。所有散光，近视， 远视，或屈光参差的程度将是 经99%的受访者更正后，将被归类为高风险 用于屈光性弱视，并将有眼镜处方。 散光矫正50%至98%的儿童 在接受调查的人中，将属于中等风险组； 儿童将被随机分配来观看奇观 修正或不修正眼镜。剩下的孩子们 将属于低风险组，不会戴眼镜。 阶段3：屈光不正和视力的后续评估 视力检查将每隔一、二、三次进行 几年，以确定奇观校正是否会减少 最佳矫正视力低于正常的患病率。初级阶段 分析将与最佳矫正视力结果进行比较。 从被随机安排到眼镜矫正的儿童 结果来自那些被随机分成不同场景的人 更正。据推测，儿童的比例 视力低于正常的人在以下人群中会更小 与儿童组相比，随机选择戴眼镜的儿童 随机化，不戴眼镜。 这项研究将显示散光对视力的影响 发展，并将决定是否纠正 学龄前几年的散光会阻止 屈光性弱视的发展，或产生改变 在正视化方面。

High levels of astigmatism exist among Native American peoples. While the prevalence of astigmatism is well studied, its developmental course and visual consequences are poorly understood. the goal of the proposed research is to establish the relation between astigmatism and visual development in native american children, and to determine the optimum strategy to mitigate detrimental effects of astigmatism in this population. A three-state research protocol is proposed: Stage 1: the prevalence of corneal, internal, and total astigmatism (as well as prevalence of reduced acuity and meridional amblyopia) will be examined in preschool children 6 months to 6 + years of age who are members of a Native American tribe (the Tohono O'Odham Nation) in which a high prevalence of astigmatism is present. Stage 2: spectacle correction will be provided based on guidelines resulting from a poll of 334 pediatric eye care practitioners. All children whose astigmatism, myopia, hyperopia, or anisometropia is of a magnitude that would be corrected by 99% of those polled will be classified as High risk for refractive amblyopia and will have spectacles prescribed. children whose astigmatism would be corrected by 50% to 98% of those polled will be in the Moderate Risk group; these children will be randomly assigned to receive spectacle correction or no spectacle correction. the remaining children will be in the Low Risk group and will not receive spectacles. Stage 3: Follow-up assessment of refractive effort and visual acuity will be performed at intervals of one, two and three years, to determine whether spectacle correction reduces the prevalence of below-normal best-corrected acuity. the primary analysis will be ca comparison of best-corrected acuity results from children who were randomized to spectacle correction with results from those who were randomized to no spectacle correction. It is hypothesized that the proportion of children with below normal acuity will be smaller in the group of children randomized to spectacles than in the group of children randomized to no spectacles. This study will show the effect of astigmatism on visual development and will determine whether correction of astigmatism during the preschool years prevents the development of refractive amblyopia, or produces an alteration in emmetropization.