 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. 