From the Guidelines
Transient vision loss is most commonly caused by atherosclerosis of the internal carotid artery, leading to temporary reduction of blood flow to the eye.
Causes of Transient Vision Loss
- Vascular causes: carotid artery stenosis or occlusion, atherosclerosis, dissection, arteritis, radiation-induced arteriopathy, arterial embolism, cardiogenic embolism, atheroembolism, hypotension, and intracranial hypertension 1
- Ophthalmologic causes: glaucoma, migraine, vasospastic or occlusive disease of the ophthalmic artery 1
- Other causes: cataracts, retinal or choroidal detachments, vitreous or anterior segment hemorrhage, drusen, hypercoagulability syndromes, primary vasospasm, blepharospasm, and metabolic derangements such as those seen with glucose imbalance 1 The mechanism of transient monocular blindness may involve ophthalmic artery embolism, observed as fibrin, cholesterol crystals (Hollenhorst plaques), fat, or material arising from fibrocalcific degeneration of the aortic or mitral valves 1. A complete ophthalmologic evaluation is needed to diagnose these conditions, and cross-sectional imaging is usually not necessary in cases where glaucoma, cataract, or macular degeneration are identified 1.
From the Research
Causes of Transient Vision Loss
Transient vision loss can be caused by a variety of factors, including:
- Ischemia, such as retinal vascular disease, intermittent optic nerve vascular compromise, or cerebrovascular disease 2
- Primary ocular pathology, including tear film abnormalities and corneal diseases 2
- Embolic occlusions of arteries supplying the eye, which can arise from the heart, aorta, and internal carotid arteries 3
- Retinal vasoconstriction 3
- Conditions that cause anterior ischemic optic neuropathy 3
- Papilledema and conditions intrinsic to the eye, such as optic disk drusen and colobomas 3
- Vascular disease, including carotid occlusion and thromboembolism 4
- Benign etiologies, such as migraine or vasospasm 4
- Giant cell arteritis, ocular ischemic syndrome, or a cardioembolic source 4
Systemic Conditions
Transient vision loss can also be related to systemic conditions, including:
- Multiple sclerosis, which can occur after an episode of optic neuritis 5
- Heart disease, which can cause embolic occlusions of arteries supplying the eye 3
- Neurologic and systemic disorders, which can cause optic neuritis 5
Diagnostic Approach
A detailed history-taking and complete ocular and neurological examination are crucial in determining the cause of transient vision loss 6. The aim is to determine whether the patient can be reassured or requires urgent referral for further investigation 6. A structured approach to the examination of a patient with transient vision loss can help clinicians provide accurate diagnosis and management 6.