Blood flow and hemodynamics in glaucoma

项目总结/摘要 青光眼是美国和世界范围内致盲的主要原因，其特征在于对视网膜的损害和对视网膜的损害。 视网膜神经节细胞丧失。已知视神经乳头和视网膜内的血流在视网膜病变中改变。 昏迷的眼睛。血流最初可能会增加，但在严重程度更高的眼睛中最终会减少。 昏迷性损伤。毛细血管密度随着疾病的进展而逐渐降低。还有 血流动力学改变的证据，即在视神经内测量的脉搏波形的形状 昏迷的眼睛和健康的眼睛的头部不同。不过，目前还不知道这些变化是否会发生 因为轴突的损失减少了代谢的需求;或者这些变化是否有助于视网膜病变， 神经节细胞损伤和死亡;或两者。这项提案将详细研究血液流动的变化， 血液动力学发生在青光眼的不同阶段。我们将利用新技术来衡量 血管系统的不同方面，并将其与疾病状态和进展，无论是单独还是在 组合.在目标1中，我们将测量视神经乳头内的血流量，以及当它通过 在一些实施例中，测量和量化乳头周围视网膜，以量化流量以及测量和量化脉搏波形。这 将使我们能够测试在被认为是青光眼嫌疑人的眼睛中观察到的流量差异是否 可以诊断测量的疾病过程的早期部分，和/或反映长期的 可以用来预测青光眼易感性的差异。在目标2中，我们还将衡量系统 脉冲波形在同一个人。这将使我们能够确定血液动力学的差异 由于病理生理过程，可以诊断性测量的眼睛局部化;和/或 代表青光眼的系统性风险因素。在目标3中，我们将测量灌注血管的面积， 在视神经乳头和视乳头周围视网膜。这将使我们能够确定， 在一些毛细血管被修剪后，剩余的血管可能会造成进一步的损伤。 总之，这些目标将揭示血管变化和青光眼之间关系的多个方面， 回答尚未解决的重大问题。总体而言，该项目将在以下方面取得重大进展： 青光眼的诊断工具和机理理解。

Project Summary / Abstract Glaucoma is a leading cause of blindness both in the US and worldwide, and is characterized by damage to and loss of retinal ganglion cells. It is known that blood flow within the optic nerve head and retina are altered in glaucomatous eyes. Flow may initially increase, but is eventually decreased in eyes with more severe glaucomatous damage. The capillary density gradually decreases as the disease progresses. There is also evidence of altered hemodynamics, in that the shape of the pulse waveform measured within the optic nerve head differs between glaucomatous and healthy eyes. However, it is not yet known whether these changes occur because axon loss has reduced the metabolic demand; or whether the changes contribute towards retinal ganglion cell damage and death; or both. This proposal will examine in detail the changes in blood flow and hemodynamics that occur at different stages of glaucoma. We will leverage new technologies to measure different aspect of the vasculature, and relate them to disease status and progression, both individually and in combination. In Aim 1, we will measure blood flow within the optic nerve head and as it passes through the peripapillary retina, both to quantify the amount of flow and to measure and quantify the pulse waveform. This will allow us to test whether the observed differences in flow in eyes that are considered glaucoma suspects are an early part of the disease process that could be measured diagnostically, and/or reflect longstanding differences that could be used to predict susceptibility to glaucoma. In Aim 2, we will also measure the systemic pulse waveform in the same individuals. This will allow us to determine whether differences in hemodynamics that could be measured diagnostically are localized to the eye due to pathophysiologic processes; and/or represent a systemic risk factor for glaucoma. In Aim 3, we will measure the area of perfused blood vessels, both in the optic nerve head and the peripapillary retina. This will allow us to determine whether flow is altered within the remaining vessels after some of the capillaries have been pruned, potentially causing further damage. Together, these aims will reveal multiple facets of the relation between vascular changes and glaucoma, and answer major questions that have remained unresolved. Overall, the project will provide substantial advances in both diagnostic tools and mechanistic understanding of glaucoma.