Correlation of Flicker Induced and Flow Mediated Vasodilatation in Patients With Endothelial Dysfunction and Healthy Volunteers
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 80
- 试验地点
- 1
- 主要终点
- Retinal vessel diameters (Retinal vessel analyzer)
研究概览
简要总结
A couple of studies have shown that illuminating the eye with diffuse flickering light is accompanied by an increase of retinal vessel diameters, optic nerve head blood flow and retinal blood flow. We have recently used this visual stimulation technique as a new and powerful tool for the non-invasive investigation of vascular reactivity. Additionally, we could show that this response is diminished in patients with vascular pathologies and that the response is dependent on nitric oxide, indicating that flicker induced vasodilatation may reflect endothelial dysfunction and may be a new approach to test endothelial function in vivo.
One of the most widely used method for the assessment of endothelial function is flow mediated dilatation (FMD). FMD has been shown to give a reliable estimate of vascular function in vivo. In the present study, we set out to compare the standard method for the evaluation of endothelial function, FMD, to flicker induced vasodilatation in the retina.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Patients with diabetic retinopathy:
- •Men and women aged > 18 years.
- •Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant.
- •Inclusion criteria of patients are insulin dependent diabetes mellitus (IDDM) with non or mild non-proliferative diabetic retinopathy. Patients with no signs of diabetic retinopathy (level 1) or patients with one or more microaneurysms (level 2) will be included. Level of diabetic retinopathy will be assessed according to the criteria defined in the AREDS-study.(1991)
- •serum cholesterol < 250 mg/dl (treated or untreated)
- •Patients with mild hypertension and/or hypercholesterinemia:
- •Men and women aged > 18 years.
- •mild essential hypertension defined as a blood pressure meeting the criterion of hypertension grade 1 of the World Health Organisation blood pressure classification
- •systolic blood pressure between 140 and 159 mmHg and diastolic blood pressure between 90 and 99 mmHg and/or
- •serum cholesterol > 250 mg/dl
- •blood pressure will be measured at two different occasion in a sitting positions
- •Healthy subjects:
- •Men and women aged > 18 years.
- •Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
- •normal ocular findings
- •serum cholesterol < 200 mg/dl
- •systolic blood pressure between 110mmHg and 140mmHg
- •diastolic blood pressure < 90 mmHg
排除标准
- •Abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
- •Symptoms of a clinically relevant illness in the 3 weeks before the first study day
- •Blood donation during the previous 3 weeks
- •other ocular pathologies than diabetic retinopathy level 1 or 2
- •History or family history of epilepsy
- •Ametropy greater or equal than 3 dpt
- •systolic blood pressure < 100mmHg
- •diastolic blood pressure < 75mmHg
- •pregnant or lactating women
研究组 & 干预措施
3
age/sex matched healthy control subjects
干预措施: Zeiss Retinal Vessel Analyzer (RVA), Stimulation with Flicker-light (Device)
1
IDDM
干预措施: Forearm blood flow measurement, Flow mediated dilation (FMD) (Procedure)
1
IDDM
干预措施: Zeiss Retinal Vessel Analyzer (RVA), Stimulation with Flicker-light (Device)
2
Hypercholesterolemia and/or Hypertension
干预措施: Forearm blood flow measurement, Flow mediated dilation (FMD) (Procedure)
2
Hypercholesterolemia and/or Hypertension
干预措施: Zeiss Retinal Vessel Analyzer (RVA), Stimulation with Flicker-light (Device)
3
age/sex matched healthy control subjects
干预措施: Forearm blood flow measurement, Flow mediated dilation (FMD) (Procedure)
结局指标
主要结局
Retinal vessel diameters (Retinal vessel analyzer)
时间窗: 8 min
Forearm Blood Flow
时间窗: 8 min
次要结局
未报告次要终点