Painful
Arteritic anterior ischemic optic neuropathy
Optic neuritis
Temporal arteritis†
Painless
Amaurosis fugax
Central retinal artery occlusion (CRAO)†
Central retinal vein occlusion (CRVO)†
High altitude retinopathy
Open-angle glaucoma
Posterior reversible encephalopathy syndrome (PRES)<unk> †
Stroke†
Vitreous hemorrhage
Traumatic optic neuropathy (although may have pain from the trauma)
Arteritic anterior ischemic optic neuropathy
Optic neuritis
Temporal arteritis†
Amaurosis fugax
Central retinal artery occlusion (CRAO)†
Central retinal vein occlusion (CRVO)†
High altitude retinopathy
Open-angle glaucoma
Posterior reversible encephalopathy syndrome (PRES)<unk> †
Stroke†
Vitreous hemorrhage
Traumatic optic neuropathy (although may have pain from the trauma)
†Emergent Diagnosis
Ocular causes
Floaters and/or flashes
Posterior vitreous detachment
Retinal tear or<unk> 
Posterior uveitis
Predominantly floaters
Vitreous hemorrhage secondary to proliferative retinopathy
Sympathetic ophthalmia
Predominantly flashes
Oculodigital stimulation
Rapid eye movements
Neovascular age-related macular degeneration
Nonocular causes
Migraine aura (classic)
Migraine aura (acephalgicmigraine)
Occipital lobe disorders
Postural hypotension
Floaters and/or flashes
Posterior vitreous detachment
Retinal tear or<unk> 
Posterior uveitis
Predominantly floaters
Vitreous hemorrhage secondary to proliferative retinopathy
Sympathetic ophthalmia
Predominantly flashes
Oculodigital stimulation
Rapid eye movements
Neovascular age-related macular degeneration
Posterior vitreous detachment
Retinal tear or<unk> 
Posterior uveitis
Vitreous hemorrhage secondary to proliferative retinopathy
Sympathetic ophthalmia
Oculodigital stimulation
Rapid eye movements
Neovascular age-related macular degeneration
Migraine aura (classic)
Migraine aura (acephalgicmigraine)
Occipital lobe disorders
Postural hypotension
Retinal detachment
Painful
Optic neuritis
Arteritic anterior ischemic optic neuropathy
Retinal hemorrhage
Traumatic optic neuropathy
Temporal arteritis†
Posterior vitreous detachment