RETINAL BLOOD FLOW MEASUREMENT

这项拟议研究的目标是完善和测试我们的 测量视网膜血流量的新方法--荧光泡 系统，它使用扫描激光检眼镜和数字图像 能够记录和数字化视频血管造影的分析系统 查看含有亚淬灭浓度的囊泡的运动 通过视网膜大循环、黄斑和视神经头进行染色 微循环和脉络膜血管。为此，我们建议 具体目标如下：1)体外确定最有效的 胶囊化染料的浓度，以使荧光最大化 使用视网膜血管模型来评估不同的 囊泡大小、染料和染料浓度的组合；2)确定 囊泡的大小、磷脂成分、电荷和结构 脂质体对荧光物质存活时间和清除的影响 首先在兔眼体内测试来自循环的囊泡 然后在猴眼中；3)绘制正常视网膜中的血流图 一种使用荧光泡系统的非人灵长类动物；追踪 清晰的荧光小泡在覆盖层上的运动 连续的视频帧将允许计算血液的速度 在视网膜、黄斑、视神经头的大小血管中流动， 和脉络膜；4)观察药物对血流动力学的反应 改变血液粘度的试剂(右旋糖苷)和一种引起 非人灵长类动物视网膜的血管扩张(山梨碱)；变化 可以同时、客观地监测由这些制剂产生的 在整个视网膜大循环和黄斑微循环中； 和5)绘制正常非人类灵长类眼睛的脉络膜血流图 荧光囊泡系统；两种荧光囊泡 将使用两种染料单独封装。《荧光报》 囊泡系统克服了扫描激光眼底镜检查的局限性 在测量血流量方面。它允许客观地测量血流量 在任何尺寸的容器中的速度。糖尿病视网膜病变是一只致盲的眼睛 涉及视网膜血流的疾病。慢性阻塞性肺疾病并发症的诊断 视网膜病变发生前的糖尿病，以及评估 药物和全视网膜等治疗的有效性 光凝，可以通过使用荧光泡系统来改善。 视神经头毛细血管可改善青光眼的治疗 用这种方法提供的血流数据。即将到来的中央视网膜 静脉阻塞也可以通过测定视网膜血流量来诊断， 从而使治疗更早开始。

The objective of this proposed study is the refinement and testing of our new approach to retinal blood flow measurement, the fluorescent vesicle system, which uses a scanning laser ophthalmoscope, and a digital image analysis system capable of recording and digitizing video angiograms to view the movement of vesicles containing a subquenched concentration of dye through the retinal macrocirculation, the macular and optic nerve head microcirculation, and the choroidal vessels. To this end, we propose the following specific aims: 1) to determine in vitro the most efficient concentrations of encapsulated dyes in order to maximize the fluorescence of the vesicles, using a model of retinal vessels to evaluate various combinations of vesicle size, dye and dye concentration; 2) to determine how vesicle size, phospholipid composition, charge, and structure of the liposomes affect the survival time and clearance of the fluorescent vesicles from the circulation by testing in vivo first in the rabbit eye and then in the monkey eye; 3) to map blood flow in the normal retina in a nonhuman primate using the fluorescent vesicle system; tracing the movement of well-defined fluorescent vesicles on overlays constructed from successive video frames will allow calculation of the velocity of blood flow in large and small vessels of the retina, macula, optic nerve head, and choroid; 4) to investigate hemodynamic responses to a pharmacological agent that alters blood viscosity (dextran) and a drug that causes vasodilation (anisodamine) in the nonhuman primate retina; changes produced by these agents can be monitored simultaneously and objectively in the entire retinal macrocirculation and the macular microcirculation; and 5) to map choroidal blood flow in a normal nonhuman primate eye using the fluorescent vesicle system; two kinds of fluorescent vesicles separately encapsulated with two dyes will be used. The fluorescent vesicle system overcomes the limitations of scanning laser ophthalmoscopy in measuring blood flow. It allows objective measurement of blood flow velocity in any size vessel. Diabetic retinopathy is a blinding eye disease involving retinal blood flow. Diagnosis of complications of diabetes before retinopathy develops, as well as evaluating the effectiveness of treatments such as pharmacological agents and panretinal photocoagulation, may be improved by using the fluorescent vesicle system. Management of glaucoma may be improved with optic nerve head capillary blood flow data provided with this approach. Impending central retinal vein occlusion can also be diagnosed by determining retinal blood flow, allowing treatment to begin earlier.