What are the clinical features, diagnostic workup, acute treatment, and preventive therapy for basilar artery (basilar‑type) migraine in adolescents and young adult females?

Basilar Artery Migraine (Migraine with Brainstem Aura)

Clinical Features

Basilar artery migraine—now termed "migraine with brainstem aura"—presents with migraine headache accompanied by at least two brainstem or bilateral hemispheric aura symptoms, occurring primarily in adolescents and young adult females. 1

Characteristic Aura Symptoms

The diagnosis requires at least two attacks featuring specific brainstem-origin symptoms 1, 2:

• Dysarthria (slurred speech) 2
• Vertigo (spinning sensation) 2
• Tinnitus (ringing in ears) 2
• Impaired hearing 2
• Diplopia (double vision) 2
• Bilateral visual symptoms (not unilateral) 2
• Ataxia (cerebellar-type incoordination) 2
• Bilateral paresthesias (pins-and-needles in both sides simultaneously) 2
• Decreased level of consciousness (ranging from confusion to syncope) 2

Typical Patient Profile

• Age of onset: Usually before age 25, with peak incidence in children and adolescents 1, 2
• Sex predominance: Female > male 2
• Aura characteristics: Symptoms develop gradually over ≥5 minutes and last 5–60 minutes, followed by headache within 60 minutes 3

Diagnostic Workup

Brain MRI without contrast is recommended for all patients with suspected migraine with brainstem aura to exclude posterior fossa pathology and other high-morbidity conditions. 1

Mandatory Investigations

• MRI brain without contrast is the baseline imaging modality 1
• Consider contrast-enhanced or vascular imaging (MRA or CTA) if vascular pathology is suspected 1
• EEG should be obtained when complex partial seizures are in the differential 1, 2
• Lumbar puncture with CSF analysis is indicated if infection or subarachnoid hemorrhage cannot be excluded clinically 1

Critical Differential Diagnoses to Exclude

The following conditions carry high morbidity/mortality and must be ruled out 1, 2, 4:

• Posterior fossa structural lesions (tumor, arteriovenous malformation, Chiari malformation)
• Vertebrobasilar insufficiency or stroke
• Complex partial seizures (temporal lobe epilepsy)
• CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy)
• MELAS (Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes)
• Hemiplegic migraine with cerebellar signs
• Vestibular migraine (recurrent vertigo without other brainstem symptoms)

Diagnostic Criteria

At least five attacks are required for definitive diagnosis of migraine without aura; at least two attacks with specific aura characteristics are needed for migraine with aura subtypes 5

Acute Treatment

The acute pharmacological management of migraine with brainstem aura remains controversial, particularly regarding triptan use. 1, 6

First-Line Acute Therapy

• NSAIDs (ibuprofen 400–800 mg, naproxen 500–825 mg) are the safest first-line option 3
• Antiemetics (metoclopramide 10 mg or prochlorperazine 10 mg) provide synergistic analgesia and treat nausea 3, 7

Triptan Controversy

Triptans are formally contraindicated in basilar-type migraine according to FDA labeling and traditional teaching, despite the absence of data proving vasospasm in this condition. 6

• The contraindication stems from theoretical concerns about brainstem vasoconstriction, not from documented adverse events 6
• Some experts argue this prohibition is outdated given the neural (not vascular) mechanism of brainstem aura 1, 6
• In clinical practice, avoid triptans in basilar-type migraine until the contraindication is formally revised 6

Alternative Acute Options

• Intranasal or IV dihydroergotamine (DHE) has efficacy for acute migraine but shares theoretical brainstem vasoconstrictive concerns 7
• Ketorolac 30 mg IV provides rapid parenteral NSAID therapy without vasoconstrictive risk 7
• Avoid opioids and butalbital compounds due to limited efficacy, dependence risk, and medication-overuse headache 3, 7

Frequency Limits

Limit all acute medications to ≤2 days per week (≤10 days per month) to prevent medication-overuse headache. 3, 7

Preventive Therapy

Preventive therapy is indicated when attacks occur ≥2 times per month causing disability ≥3 days, or when acute medication use exceeds twice weekly. 3, 5

First-Line Preventive Options

• Propranolol 80–240 mg/day (beta-blocker without intrinsic sympathomimetic activity) 3, 5
• Topiramate (dose titrated to effect, typically 50–200 mg/day) 3, 5
• Candesartan (angiotensin receptor blocker) 5

Second-Line Preventive Options

• Amitriptyline 30–150 mg/day (particularly useful for comorbid depression or sleep disturbance) 3, 5
• Sodium valproate (800–1500 mg/day) is effective but absolutely contraindicated in women of childbearing potential due to teratogenic risk 3, 5
• Calcium-channel blockers (flunarizine, verapamil) have historical use in basilar-type migraine 5, 2

Emerging Evidence

• Lamotrigine has shown efficacy in small case series for preventing brainstem aura symptoms 8
• Betahistine chloride may be particularly useful when vertigo is the predominant aura symptom 2

Preventive Therapy Timeline

• Oral preventives require 2–3 months for full efficacy assessment 7
• CGRP monoclonal antibodies (if first-line agents fail) require 3–6 months 7

Special Considerations for Adolescents and Young Adult Females

Adolescent-Specific Recommendations

• Ibuprofen is the first-line acute medication for adolescents, dosed by body weight 9
• Bed rest alone may suffice for short-duration attacks in younger patients 3, 9
• Nasal-spray triptans (sumatriptan, zolmitriptan) are FDA-approved for adolescents aged 12–17 with typical migraine, but remain controversial in basilar-type migraine 9, 6

Preventive Options for Adolescents

• Propranolol, amitriptyline, or topiramate are recommended for prevention in children and adolescents 3

Women of Childbearing Potential

• Avoid sodium valproate entirely due to teratogenic risk 3, 5
• Use acetaminophen (paracetamol) 1000 mg for acute treatment if pregnancy is possible or confirmed 3
• Avoid preventive therapy during pregnancy if possible; if required, propranolol is relatively safer 3

Prognosis and Long-Term Management

The prognosis for migraine with brainstem aura is generally favorable, with many patients experiencing spontaneous remission or decreased attack frequency over time. 1

Monitoring and Follow-Up

• Headache diary is essential for tracking attack frequency, severity, and medication use 3, 7
• Reassess treatment response every 2–3 months after initiating or modifying therapy 5
• Specialist referral is indicated when diagnosis is uncertain, all treatments fail, or complications arise 3

Critical Pitfalls to Avoid

• Failing to obtain MRI in first-time presentations risks missing life-threatening posterior fossa pathology 1
• Prescribing triptans despite formal contraindication exposes patients to theoretical (though unproven) brainstem vasospasm risk 6
• Allowing acute medication use >2 days/week creates medication-overuse headache and converts episodic to chronic migraine 3, 7
• Prescribing valproate to women of childbearing age carries unacceptable teratogenic risk 3, 5
• Delaying preventive therapy when attacks are frequent perpetuates disability and increases risk of chronification 3, 5