Migrainous Infarction (MI):
- Definition: Rare complication of migraine with aura, leading to ischemic stroke.
- Pathophysiology:
- Vasospasm: Prolonged arterial spasm during aura, causing hypoperfusion.
- Thrombosis: Platelet activation and hypercoagulability may contribute.
- Hypoxia: Reduced cerebral blood flow during aura.
- Risk Factors:
- Younger age (often <50 years).
- Long-standing migraine with aura (especially if frequent).
- Smoking, oral contraceptives, or other prothrombotic states.
- Diagnosis:
- Imaging: MRI with diffusion-weighted imaging (DWI) shows acute ischemic lesions, often in the posterior circulation (e.g., cerebellum, occipital lobes).
- Exclusion of other causes: Rule out cardioembolic sources, dissection, or vasculitis.
- Management:
- Acute: Thrombolysis if within 4.5 hours (if no contraindications).
- Prevention:
- Avoid triggers (e.g., smoking, OCPs).
- Consider antithrombotic therapy (e.g., aspirin, clopidogrel) if recurrent.
- Migraine prophylaxis (e.g., beta-blockers, topiramate) if indicated.
- Rationale: Migraine with aura is a risk factor for stroke, and MI is a severe manifestation requiring prompt evaluation and management to prevent recurrence.