Diurnal Intraocular Pressure Variability Assessment

描述（由申请人提供）：原发性开角型青光眼（POAG）是一种眼部疾病，其特征为进行性视神经损伤，视野丧失，在许多情况下，眼压（IOP）升高。治疗性降低眼压可防止POAG的进展，是目前已知的唯一治疗POAG的方法。但是仅仅降低眼压并不总是足够的，青光眼的进展和失明在接受降低眼压治疗的青光眼患者中并不罕见。众所周知，眼压会随着时间的推移而波动，尽管平均眼压水平在治疗上已经足够，但治疗后青光眼的眼压大幅波动最近与进展有关。因此，眼压变异性是一个重要的评估参数。目前的眼压变异性模型是单日眼压变异性。我们对日常IOP行为的了解是基于对正常眼睛和青光眼进行的每天24小时（或更少）的IOP评估。基于这些一天一次的测量，我们假设IOP节律在个体的眼睛之间是对称的，并且每天都保持恒定的节奏。这一提议挑战了这一教条。根据我们自己的初步研究和少数表明患者的昼夜IOP节律随时间变化的研究，我们假设IOP变异性在正常和青光眼中都是随时间变化的混乱事件，并且知道某只眼睛在某一天的昼夜IOP节律并不能预测其他任何一天的昼夜节律。证明正常和持续的昼夜IOP节律的存在将迫使范式转向更长期的IOP变异性指标。通过收集基线和1天、1周、1个月、6个月和1年后的每日IOP测量值，我们可以实现描述正常和青光眼眼内眼压的短期（天）、中期（周至月）和长期（年）日变异性的具体目标。我们假设，在正常和青光眼的眼睛中重复的每日眼压测量将显示出患者之间、同侧眼睛之间以及患者和眼睛内部随时间的昼夜IOP节律的显著差异。

DESCRIPTION (provided by applicant): Primary open-angle glaucoma (POAG) is an ocular disease characterized by progressive optic nerve damage, visual field loss and in many cases, elevation of intraocular pressure (IOP). Therapeutically lowering IOP confers protection against progression of POAG, and is the only known treatment for POAG. But simply lowering IOP is not always enough, and glaucomatous progression and blindness are not uncommon in patients receiving IOP-lowering treatment for glaucoma. IOP is known to fluctuate over time, and large fluctuations of IOP in treated glaucomatous eyes have recently been associated with progression despite mean IOP levels that appear to be therapeutically adequate. Thus, IOP variability is an important parameter to assess. The current model for IOP variability is single-day diurnal IOP variability. Our knowledge of diurnal IOP behavior is based on many single-day 24-hour (or less) diurnal IOP assessments in normal and glaucomatous eyes. Based on these one-day-in-time measurements, it is assumed that this IOP rhythm is symmetric between fellow eyes of individuals and remains a constant rhythm from day to day. This proposal challenges that dogma. Based upon our own preliminary studies and a very few studies which suggest that diurnal IOP rhythms change in patients over time, we hypothesize that IOP variability is a chaotic event over time in both normal and glaucomatous eyes, and that knowing the diurnal IOP rhythm of a given eye on a given day does not permit prediction of the diurnal rhythm on any other day. Disproving the existence of a regular and sustained diurnal IOP rhythm would force a paradigm shift toward more long-term indices of IOP variability. By collecting diurnal IOP measurements at baseline and 1 day, 1 week, 1 month, six months, and one year later, we can achieve our specific aims to characterize the short- (days), intermediate- (weeks to months), and long-term (year) diurnal variability of intraocular pressure in normal and glaucomatous eyes. We hypothesize that repeated diurnal measurements of intraocular pressure in normal and glaucomatous eyes will demonstrate significant variability in the diurnal IOP rhythms between patients, between fellow eyes, and within patients and eyes over time.