Develo of Optical Alignment System for Raman Retina Eval

视网膜拉曼评估光学对准系统的开发

• 批准号: 7013053
• 负责人: paul smith
• 金额: --
• 依托单位: OFFICE OF THE DIRECTOR, NATIONAL INSTITUTES OF HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7013053
• 关键词: Raman spectrometry; biomedical equipment development; clinical biomedical equipment; cornea; diagnosis design /evaluation; eye disorder diagnosis; fiber optics; human subject; lasers; macular degeneration; noninvasive diagnosis; retina; video recording system

This instrumentation assesses the level of the carotenoid pigments, lutein and zeaxanthin, present in the human macula. These pigments protect against age-related macula degeneration, the leading cause of blindness in the elderly. Resonance Raman spectroscopy is a non-invasive methodology that allows quantification of these macular pigments in the retina. The Resonance Raman Spectrometer, which was developed at the University of Utah, requires the subject to align an illuminated fiber optic array, which simulates the argon ion excitation laser beam, with a representation of the detector optical pupil prior to initiating the laser pulse that produces the Raman backscattered signal. This alignment is a simple matter with patients who possess good visual acuity, but degeneration of the macular makes the alignment a difficult problem. To overcome this problem, the instrument was modified to provide a video presentation of the subject?s eye centered on the cornea. A low-level helium-neon laser was introduced into the instrument?s optical path co-linear with the optical axis of the Raman excitation and emission pathways. The video camera captures the scattered and reflected laser beam from the front surface of the cornea. The physician adjusts the position of the subject?s eye until the laser beam is centered on the cornea. This is accomplished by orienting to fiducial marks and by the increase in reflected intensity as the front surface of the cornea becomes perpendicular to the incident alignment laser beam.

该仪器评估人类黄斑中存在的类胡萝卜素色素、叶黄素和玉米黄质的水平。这些色素可以防止与年龄相关的黄斑变性，这是老年人失明的主要原因。共振拉曼光谱是一种非侵入性方法，可以对视网膜中的这些黄斑色素进行定量。 犹他大学开发的共振拉曼光谱仪要求受试者在启动产生拉曼反向散射信号的激光脉冲之前，将模拟氩离子激发激光束的照明光纤阵列与检测器光瞳的表示对齐。对于视力良好的患者来说，这种对准是一件简单的事情，但是黄斑变性使对准成为一个难题。为了克服这个问题，对仪器进行了修改，以提供以角膜为中心的受试者眼睛的视频演示。将低水平氦氖激光器引入仪器的光路中，与拉曼激发和发射路径的光轴共线。摄像机捕获来自角膜前表面的散射和反射激光束。医生调整受试者眼睛的位置，直到激光束位于角膜中心。这是通过定向基准标记以及当角膜前表面垂直于入射对准激光束时增加反射强度来实现的。