Contraindication to the use oxygen (O2): Acute or chronic respiratory insufficiency

Pregnant or lactating woman

Inability to see fundus (cataract), retinopathy, glaucoma

Use of vasoactive substances (eg nasal decongestants, triptans, alkaloids) in the last 48 hours

Use of nonsteroidal anti-inflammatory drugs (ibuprofen, naproxen, ..) and steroids (corticosteroids) in the last 48 hours

Known Diabetes or taking antidiabetics in the last 48 hours

Use of statins in the last 48 hours

Known hypertension or antihypertensive treatment in the last 48 hours

Any cardiac pathology (valvulopathy, angina, ventricular arrhythmia or atrial fibrillation), vascular (arteritis obliterating the lower limbs, stenosis of the arteries with encephalic destiny, coronary artery disease) or significant respiratory (asthma, Chronic obstructive pulmonary disease, interstitial pathology)

Alcohol consumption within 8 hours

Ophthalmoparesis or incapacitating nystagmus (impossibility of correctly evaluating the fundus)

Exploration of Microcirculatory Alteration and Endothelial Dysfunction by Adaptive Optics in Multiple Sclerosis

What this study is about