OPTICAL AND RETINAL LIMITS TO HUMAN VISUAL PERFORMANCE

光学和视网膜对人类视觉性能的限制

• 批准号: 6126657
• 负责人: LARRY N THIBOS
• 金额: $ 21.98万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-01-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6126657
• 关键词: amblyopia; behavioral /social science research tag; clinical research; cornea; diagnosis design /evaluation; eye disorder diagnosis; eye refractometry; form /pattern perception; human subject; keratoconjunctivitis sicca; keratoconus; light scattering; neural information processing; neuroanatomy; psychophysics; retina; tear; vision tests; visual fields; visual perception; visual stimulus

DESCRIPTION (Adapted from applicant's abstract): The long-term goal of our research program is to understand how optical and retinal factors constrain the quality of visual experience. In central vision, poor optical quality of the eye is the chief cause of poor visual performance on many visual tasks, especially in clinically abnormal eyes. We propose to use newly developed technologies to investigate the underlying physiological mechanisms which are responsible for these optical limitations to vision. The results will improve our understanding of the optical consequences of clinical conditions such as dry eye and keratoconus, which may ultimately lead to new diagnostic and treatment strategies. Aim 1 is to test the hypothesis that the corneal tear film provides an optically smooth refracting surface which reduces light scatter and refractive aberrations that would otherwise degrade the retinal image and reduce visual performance. This hypothesis predicts that disruption of the tear film by blink suppression will expose the underlying rough, irregular surface of the cornea, thereby increasing light scatter and refractive aberrations which will degrade the retinal image. The predicted outcome is blurry vision and reduced visual performance. To test these predictions we will use a Shack-Hartmann aberrometer to objectively measure refractive aberration and light scatter simultaneously at 200 or more points in the eye's pupil. The results will be compared with topographic maps of tear film disruption obtained simultaneously by fluorescein and by retro-illumination imaging of the pupil. Image quality will also be compared with visual acuity and contrast sensitivity during tear film disruption. Aim 2 is to test the hypothesis that corneal shape is responsible for the majority of the eye's refractive aberrations. In the process, we also aim to resolve the current controversy over whether optical aberrations due to corneal shape compensate or exacerbate the aberrations of the remaining optical elements of the eye. This hypothesis will be tested in normal eyes and in clinical patients with highly abnormal corneal shape caused by the corneal disease keratoconus. We will measure the aberrations of the cornea with topographic videokeratoscopy for comparison against aberrations of the whole eye measured with the Shack-Hartmann aberrometer. The effect of corneal aberrations and scatter in keratoconic eyes on visual performance will also be measured by using simulated retinal images computed with an optical model of the keratoconic eye as visual stimuli for normal eyes. Aim 3 is to develop a comprehensive, quantitative optical model of the eye which accounts for constraints on retinal image quality and on visual performance imposed by optical imperfections of the eye. Results from our studies of the optical function of the tear film and cornea will be incorporated in to the optical model to provide a quantitative, functional description of the effect of the eye's optical imperfections on retinal image quality and on visual performance in normals, dry-eye patients, and keratoconus patients.

描述（摘自申请人摘要）：我们的长期目标 研究计划是了解光学和视网膜因素如何限制 视觉体验的质量。在中央视觉中， 眼睛是许多视觉任务中视觉表现差的主要原因， 特别是在临床异常的眼睛中。我们建议使用新开发的 研究潜在生理机制的技术， 造成了视觉上的限制结果会有所改善 我们对临床条件的光学后果的理解， 干眼症和圆锥角膜，这可能最终导致新的诊断和 治疗策略。 目的1是检验角膜泪膜提供角膜刺激的假设 光学平滑的折射表面，其减少光散射和折射 否则会降低视网膜图像和降低视觉的像差 性能这一假说预测眨眼对泪膜的破坏 抑制将暴露角膜的底层粗糙、不规则表面， 从而增加光散射和折射像差， 视网膜图像。预测的结果是视力模糊和视力下降 性能为了检验这些预测，我们将使用夏克-哈特曼像差仪 同时客观测量屈光像差和光散射 瞳孔中的200个或更多点。结果将与 用荧光素同时获得泪膜破裂的地形图 以及通过瞳孔的回射照明成像。图像质量也将 与泪膜中的视力和对比敏感度相比， 破坏 目的2是检验角膜形状是导致 大部分眼睛的屈光不正。在此过程中，我们还旨在 解决了目前关于角膜病变是否导致光学像差的争议， 形状补偿或加剧剩余光学元件的像差 眼睛的元素。这一假设将在正常眼睛和 临床上由角膜引起的高度异常的角膜形状的患者 圆锥角膜病我们将测量角膜的像差， 地形图视频角膜镜检查与整体像差比较 用Shack-Hartmann像差仪测量眼睛。角膜的影响 还将讨论圆锥角膜眼的像差和散射对视觉性能的影响， 通过使用用光学模型计算的模拟视网膜图像测量， 圆锥角膜眼作为正常眼的视觉刺激。 目标3是建立一个全面的、定量的眼睛光学模型 这说明了视网膜图像质量和视觉上的限制， 由眼睛的光学缺陷造成的性能。源自我们的 对泪膜和角膜的光学功能的研究将是 结合到光学模型中，以提供定量的、功能性的 眼睛光学缺陷对视网膜图像影响的描述 对正常人、干眼症患者和圆锥角膜的视觉性能的影响 患者