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: 6721426
• 负责人: LARRY N THIBOS
• 金额: $ 22.35万
• 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 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6721426
• 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（改编自申请人的摘要）：我们的长期目标 研究计划是了解光学因素和视网膜因素如何限制 视觉体验的质量。在中央视觉中，光学质量差 眼睛是许多视觉任务视觉表现不佳的主要原因， 特别是在临床异常的眼睛中。我们建议使用新开发的 研究基本生理机制的技术 负责这些视力的光学限制。结果将改善 我们对临床状况的光学后果的理解，例如 干眼症和角膜核，最终可能导致新的诊断和 治疗策略。 目的1是检验角膜撕裂膜提供的假设 光滑的折射表面，可减少光散射和折射率 否则会降低视网膜图像并减少视觉的畸变 表现。该假设预测，眨眼对泪膜的破坏 抑制作用将暴露基础的粗糙，不规则的角膜表面， 从而增加光散射和折射畸变，这会降解 视网膜图像。预测的结果是视觉模糊和视觉降低 表现。为了测试这些预测，我们将使用Shack-Hartmann异差计 客观地测量折射率和光同时散射 在眼睛的学生中有200点或更多点。结果将与 通过荧光素同时获得的泪膜中断的地形图 并通过对学生的恢复成像。图像质量也将是 与泪膜期间的视力和对比度敏感性相比 破坏。 目标2是检验角膜形状负责的假设 大多数眼睛的折射畸变。在此过程中，我们还旨在 解决目前关于角膜造成的光差的争议 补偿或加剧其余光学的畸变 眼睛的元素。该假设将在正常的眼睛和 角膜引起的高度异常角膜形状的临床患者 疾病角膜结构。我们将用 与整个畸变进行比较的地形视频镜检查 用Shack-Hartmann异常测量的眼睛。角膜的效果 视觉性能的畸变和散布也将是 通过使用模拟的视网膜图像测量 角膜角眼作为正常眼睛的视觉刺激。 AIM 3是开发眼睛的全面，定量的光学模型 哪些是对视网膜图像质量和视觉的限制 眼睛的光学缺陷所施加的性能。我们的结果 催泪膜和角膜的光学功能的研究将是 纳入光学模型以提供定量，功能性 眼睛光学缺陷对视网膜图像的影响的描述 质量和视觉性能，在正常患者，干眼患者和角膜骨中 患者。