What is the management approach for retinal migraine versus migraine with visual aura?

Retinal Migraine vs Migraine with Visual Aura: Key Distinctions and Management

Retinal migraine requires monocular visual symptoms (affecting one eye only), while migraine with visual aura causes binocular visual disturbances (affecting both eyes or both visual fields), and this distinction is critical because retinal migraine carries significant risk of permanent vision loss requiring aggressive prophylactic treatment. 1, 2

Diagnostic Differentiation

Migraine with Visual Aura

• Binocular visual symptoms affecting both eyes or both visual fields simultaneously 1
• Visual symptoms spread gradually over ≥5 minutes 1
• Aura symptoms last 5-60 minutes 1, 3
• At least one symptom is unilateral (in visual field, not eye) and at least one is positive (scintillations, zigzag lines) 3
• Accompanied by or followed by headache within 60 minutes 1, 3
• Requires at least two attacks meeting these criteria 1

Retinal Migraine

• Monocular visual loss (one eye only) - this is the defining feature 2, 4, 5
• Partial or complete visual loss lasting <1 hour 2, 4
• Visual loss is ipsilateral to the headache 2
• Most commonly affects women in second to third decade of life 2, 4
• Contrary to classification criteria, most patients have a history of migraine with aura 2

Critical Management Differences

Acute Treatment

For Migraine with Visual Aura:

• Initiate NSAIDs or aspirin as soon as aura symptoms appear to abort or diminish the subsequent headache 3
• Do NOT use triptans during the aura phase due to theoretical vasoconstriction concerns during cortical hypoperfusion 3
• Triptans can be used once headache phase begins 1

For Retinal Migraine:

• Consider acute migraine therapy to mitigate risk of permanent visual loss 6
• Complete thorough cerebrovascular evaluation to exclude other causes 6

Preventive Treatment: The Critical Difference

Retinal migraine requires aggressive prophylactic treatment even with infrequent attacks because nearly half of patients with recurrent transient monocular visual loss subsequently experience permanent monocular visual loss 2, 4, 6. This represents a potential migrainous infarction of the retina or optic nerve 6.

First-line preventive medications for both conditions:

• Propranolol 80-160 mg oral once or twice daily in long-acting formulations 1, 3
• Metoprolol 50-200 mg oral once daily 1, 3
• Topiramate 50-100 mg oral daily 1, 3

Second-line options:

• Amitriptyline 10-100 mg oral at night 1
• Candesartan 16-32 mg oral per day 1

Evaluation timeline:

• Assess treatment response within 2-3 months using headache calendars 1, 3
• Track attack frequency, severity, and medication use 1, 3

Contraception Considerations: Absolute Contraindication

All combined hormonal contraceptives containing estrogen are absolutely contraindicated in women with migraine with aura due to compounded stroke risk 1, 3. Women with migraine with aura have significantly elevated baseline ischemic stroke risk, which estrogen further increases 1, 3.

• Progestin-only contraceptives are safe alternatives 3
• This contraindication applies regardless of menstrual cycle association 1
• Retinal migraine patients likely warrant similar caution given the vascular nature of the condition 2, 4

Common Pitfalls to Avoid

Diagnostic errors:

• Failing to distinguish monocular (retinal migraine) from binocular (visual aura) symptoms - ask the patient to cover each eye alternately during symptoms 2, 5
• Assuming retinal migraine is benign because diagnostic criteria require "fully reversible" visual loss - permanent vision loss occurs in nearly 50% of cases 2, 4
• Missing other causes of transient monocular visual loss (TIA, carotid disease, cardiac emboli, thrombosis) - complete cerebrovascular workup is mandatory 6, 5

Treatment errors:

• Using triptans during aura phase in migraine with visual aura 3
• Failing to initiate prophylactic treatment in retinal migraine patients, even with infrequent attacks 2, 6
• Prescribing combined hormonal contraceptives to women with migraine with aura 1, 3

Medication overuse warning:

• Watch for medication overuse headache developing from acute medications used more than twice weekly 3
• Regular overuse for >3 months of non-opioid analgesics on ≥15 days/month or triptans on ≥10 days/month meets criteria for medication-overuse headache 3

Pathophysiology Insights

Recent evidence using OCT-angiography demonstrates acute monocular retinal oligemia during retinal migraine attacks, with hypoperfusion resolving as symptoms improve 7. This supports selective retinal ganglion cell layer spreading depression as a possible mechanism, independent from cerebral vascular changes 7. This monocular vascular involvement explains the risk of permanent ischemic complications including paracentral acute middle maculopathy, central retinal artery occlusion, and ischemic optic neuropathy 6.