Differential Diagnosis of Transient Visual Loss. Affecting One Eye
| Cause | Typical duration/characteristic features |
|---|---|
| Ischaemia due to atheroembolism from carotid artery disease or other source of embolism (amaurosis fugax) | 1–10 min. Like a shutter coming down. |
| Ischaemia due to giant cell arteritis | Variable, may have preceding visual obscurations. May affect nerve (AION), retina (CRAO) or ocular circulation as a whole (ocular ischaemic syndrome). May also cause motility disturbance – cranial nerve palsies/extraocular muscles ischaemia. |
| Retinal vasospasm | Lasts 5–60 min, migrainous features such as aura and headache. Fortification spectra/scintillating scotoma are absent as they are cortical phenomena and relate to cephalic migraine. |
| Early retinal detachment | Variable – progressively worse, painless. |
| Uveitis | Variable – progressively worse and more painful. |
| Optic neuritis | Subacute visual loss with hyperaemic optic nerve and features of optic neuropathy: decreased colour vision, field loss and RAPD. |
| Intermittent angle-closure glaucoma | Brow ache and blurred vision – may get halos around lights and feel nauseous. |
| Affecting both eyes | |
| Cause | Typical duration/characteristic features |
|---|---|
| Migraine with visual aura | Lasts 10–30 min, migrainous features such as fortification spectra/scintillating scotoma and headache. Affects both eyes. |
| Raised intracranial pressure | Obscurations lasting seconds, which may be postural. Headache and other features of raised ICP. Bilateral disc swelling with preserved visual function (i.e. normal colour vision) in early stages. Enlarged blind spot in early stages. |
| Posterior circulation transient ischaemic attack affecting visual cortex | Lasts 1–10 min. |
| Epilepsy (ictal or post-ictal) | Ictal: 3–5 min. Post-ictal: 20 min. |