Regulation of Optic Nerve Head Blood Flow During Combined Changes in Intraocular Pressure and Arterial Blood Pressure
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 40
- 试验地点
- 2
- 主要终点
- Optic nerve head pressure-flow relationship
研究概览
简要总结
Autoregulation is defined as the ability of a vascular bed to adapt its vascular resistance to changes in perfusion pressure. In the eye, several studies have reported that retinal blood flow is autoregulated over a wide range of ocular perfusion pressures. In the optic nerve head only few data are available. Large scale studies have shown that reduced ocular perfusion pressure is an important risk factor for the prevalence, the incidence and the progression of primary open angle glaucoma.
Former studies that investigated ocular blood flow autoregulation only measured choroidal blood flow. For the optic nerve head only few data are available, although it seems likely that it underlies similar autoregulatory mechanisms.
The primary goal of the present study is to gain more insight into these phenomena in humans.
The present study aims to investigate the pressure/flow relationship as a measure for optic nerve head autoregulation during combined changes of intraocular pressure and arterial pressure. Intraocular pressure will be increased by the use of a suction cup technique, mean arterial pressure will be increased by squatting. During the whole procedure, optic nerve head blood flow will be measured continuously.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Men and women aged between 18 and 35 years, nonsmokers
- •Men and women will be included in equal parts
- •Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
- •Normal findings in the laboratory testings unless the investigator considers an abnormality to be clinically irrelevant
- •Normal ophthalmic findings, ametropia less than 1 diopter
排除标准
- •Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
- •Treatment in the previous 3 weeks with any drug (except oral contraceptives)
- •Symptoms of a clinically relevant illness in the 3 weeks before the first study day
- •Blood donation during the previous 3 weeks
结局指标
主要结局
Optic nerve head pressure-flow relationship
时间窗: in total 3x on 2 study days
次要结局
未报告次要终点
研究者
Gerhard Garhofer
Ass.Prof.Priv.Doz.Dr.
Medical University of Vienna