Study of Ocular Blood Flow Using Laser Doppler Flowmetry in Patients With Glaucoma and/or OSAS
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 90
- 试验地点
- 2
- 主要终点
- ocular blood flow
研究概览
简要总结
Obstructive sleep apnea syndrome (OSAS) is a common disease, with a prevalence evaluated between 5 - 7% in the general population. OSAS is characterized by recurrent episodes of partial or complete upper airway obstruction during sleep, which are nearly systematically associated with a desaturation-reoxygenation sequence, an admitted detrimental stimulus for the cardiovascular system. It has now been demonstrated that OSAS per se is able to generate hypertension, atherosclerosis and autonomic dysfunction (high sympathic tone and increase in baseline heart rate), all conditions possibly interacting with ocular vascular regulation. OSAS has major consequences on the ocular level since it is associated with a higher frequency of optic neuropathies, such as glaucoma and nonarteritic ischemic optic neuropathy (NAION), both with functional severe prognosis. Most of vascular changes associated with OSAS have been studied at the level of macrovasculature. In terms of physiopathology, the main effects on the vascular system in OSAS are sympathetic hyperactivity, oxidative stress, development of endothelial dysfunction, systemic inflammation and metabolic alterations such as the appearance of insulin resistance. All these mechanisms can affect the microcirculation of the eye, especially the optic nerve and choroid. Our hypothesis is that the eye microvasculature is affected by OSAS, and these lesions may be detected via a reduced autoregulation of blood flow in humans.
This project aims to demonstrate, quantify, and analyze the vascular modifications of the eye associated with OSAS trough a comparative clinical study on glaucoma patients and OSAS patients and matched healthy subjects for the regulation of the eye blood flow using confocal laser Doppler flowmetry (LDF). The regulation of the ocular blood flow will be assessed using several stimuli and measured using a new confocal LDF.
详细描述
JUSTIFICATION OF THE PROJECT Obstructive sleep apnea syndrome (OSA) is an under diagnosed disease affecting 5% of the general population. This disease is associated with an increase in the risk for cardiovascular disease (high blood pressure, coronary disease, and stroke). Two optic neuropathies are associated with OSA: glaucoma and nonarteritic anterior ischemic optic neuropathy (NAION). Glaucoma is a frequent progressive optical neuropathy in industrialized countries and one of the leading causes of blindness in the world. Normal tension glaucoma, a vascular form of glaucoma, is the form most frequently associated with OSAS. In addition, in nonglaucomatous OSA patients, there is a diffuse reduction in optic nerve layer thickness correlated with OSA severity, strongly suggesting optic nerve involvement in these patients. Moreover, recent studies have shown that 90% of patients presenting NAION have OSA. These clinical and epidemiological data suggest a causal relation between OSA and the onset of optic neuropathy.
OBJECTIVES: This physiopathological study aims to demonstrate, quantify, and analyze the vascular modifications associated with OSA through:
- A comparative study on glaucoma patients and OSAS patients, with or without NAION, and healthy subjects matched for age, sex, and body mass index: the eye vascular modifications will be quantified using confocal laser Doppler flowmetry.
EXPERIMENTAL SCHEDULE The aim of this study is to characterize ocular blood flow (choroid and optic nerve) regulation in patients in 4 populations: (1) glaucoma patients (2) OSA patients without clinical evidence of optic nerve disease, (3) OSA patients with NAION, (4) matched healthy subjects . OSA patients of group 2 and 3 will be studied 3-6 months after nCPAP treatment.
- Recruitment and screening visit: each subject will undergo a general examination. The ocular examination includes visual acuity, intraocular pressure, biomicroscopy and fundus examination, visual field (Humphrey 24/2 SITA-STANDARD) and measurement of the thickness of the optic nerve fiber layer using optical coherence tomography (OCT 3 Zeiss). In order to assess the cardiovascular phenotype, the cardiovascular examination will be completed, by an electrocardiogram, an ambulatory blood pressure monitoring, and echocardiography. A blood sample will be also analyzed: lipid analysis, hemogram, ionogram, glucose, cholesterol, triglycerides. A polysomnography will be performed for all subjects for the diagnosis of OSA, and the calculation of a respiratory disturbance index (RDI, sleep apnea defined as a RDI >15 per hour).
- Baseline measurements of blood flow of the optic nerve head:
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
- Single (Participant)
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •the age is between 18 years & 80 years
- •nobody affiliated with social security
- •including informed & signed consent
排除标准
- •congenital malformation leading to an excavation of the optic nerve or a deficit of the visual field
- •any eye disease associated, including refraction disorder ( > 4 diopters) , retinal disease, cataract, corneal opacity)
- •taking medication which can have an action on blood pressure or regulation ( vasoconstrictors, vasodilators, beta-agonists and antagonists, nitrates, theophylline, dipyridamole, sildenafil, immunosuppressive, corticosteroid or Non-steroidal anti-inflammatory drugs (> 10 days), hormonal therapy), sedative drug (antidepressive, anxiolytics, hypnotics) drops with activity on regulation of ocular pressure ( beta-blockers)
- •all ophthalmic drops
- •current infection ( acute hepatitis B, hepatitis C active, HIV infection)
- •known hypertension or suspected
- •Electrolyte disturbance
- •Pathology that can affect the regulation of blood pressure : parkinson' disease, patients transplanted kidney or cardiac arrhythmias, severe heart failure atrial fibrillation or frequent extrasystole (> 10 / minute)
- •nocturnal Professional activity
- •History of surgery or carotid stenting
- •Previous treatment of Obstructive Sleep Apnea Syndrome by continuous positive pressure, propulsion prosthesis mandibular or maxillofacial surgery
- •No predictable compliance with the protocol
- •Patients participating in another biomedical research
- •Patients with no affiliation to social security
- •narrow irido corneal angle
结局指标
主要结局
ocular blood flow
时间窗: 9 months
次要结局
- comparisons between OSAS patients and healthy controls(6 years)