Retinal Artery OcclusionRetinal ArterySusac SyndromeFluorescein AngiographyArterial Occlusive DiseasesFundus OculiGlaucoma, NeovascularRetinal DiseasesAmaurosis FugaxRetinal VeinSneddon SyndromeBlindnessMesenteric Vascular OcclusionOphthalmic ArteryVisual AcuityParacentesisInfarction, Middle Cerebral ArteryOphthalmodynamometryCarotid Artery DiseasesOptic Neuropathy, IschemicArteriesConstrictionBrain Ischemia