Migraine with brainstem aura.
Migraine with brainstem aura (MBA), previously known as basilar-type migraine or basilar artery migraine, is a rare and complex subtype of migraine that affects the brainstem, a vital part of the central nervous system responsible for controlling many essential functions like breathing, heart rate, and balance. Unlike typical migraines, which may only involve visual or sensory disturbances, migraine with brainstem aura presents with symptoms that affect several neurological functions associated with the brainstem. These symptoms can be alarming and sometimes mimic more severe conditions like strokes or seizures.
Here’s an in-depth look at the symptoms, mechanisms, and diagnosis of migraine with brainstem aura, as well as its treatment and impact on daily life.
1. Symptoms of Migraine with Brainstem Aura
The defining feature of migraine with brainstem aura is the aura phase, which affects the brainstem and may include a range of neurological symptoms. These symptoms often develop gradually, lasting for several minutes to an hour, and they usually resolve before or as the headache phase begins. However, in some cases, the aura can persist even after the headache subsides.
1.1 Brainstem Aura Symptoms
The aura in migraine with brainstem aura can include various symptoms related to dysfunction in the brainstem or the posterior part of the brain (occipital lobes and cerebellum). These symptoms may occur in isolation or in combination, and they typically affect both sides of the body.
- Vertigo:
- A sensation of spinning, swaying, or tilting, even when the person is stationary. Vertigo is one of the most common and distressing symptoms of migraine with brainstem aura.
- Episodes can last from a few minutes to an hour or longer, and they may be exacerbated by movement or changes in position.
- Double Vision (Diplopia):
- Some individuals experience double vision or difficulty focusing during the aura phase. This is due to brainstem involvement affecting eye movement control.
- Vision may be blurred or out of alignment, leading to disorientation and difficulty performing tasks that require clear sight.
- Difficulty Speaking (Dysarthria):
- Problems with speech are common in MBA, with sufferers struggling to form words, slurring speech, or experiencing difficulty controlling the muscles involved in speaking. This is known as dysarthria.
- Speech problems are caused by dysfunction in the brainstem, which controls motor functions related to articulation and speech.
- Tinnitus and Hearing Loss:
- Ringing in the ears (tinnitus) or temporary hearing loss can occur due to the involvement of the brainstem’s auditory pathways.
- Hearing disturbances may resolve once the aura phase is over.
- Loss of Balance (Ataxia):
- Many individuals with migraine with brainstem aura experience problems with balance and coordination, known as ataxia.
- This can lead to difficulty walking, standing, or performing tasks that require precise motor control.
- Visual Aura:
- In addition to brainstem symptoms, visual disturbances are common. These may include flashing lights, blind spots (scotomas), zigzag patterns, or visual field defects.
- These visual symptoms are similar to those experienced in typical migraines with aura but are more likely to affect both sides of the visual field.
- Confusion and Disorientation:
- Cognitive difficulties such as confusion, disorientation, or feeling “spaced out” may occur during the aura phase. This can cause problems with concentration and memory.
- Some individuals may also feel a sense of unreality or detachment from their surroundings.
1.2 Headache Phase
Following the aura, most individuals experience a headache, although this may be milder than in typical migraines or even absent. When present, the headache typically shares characteristics with a common migraine:
- Severe Throbbing or Pulsating Headache:
- The pain is usually intense, often on one side of the head (unilateral), but it can also affect both sides.
- The headache can last from a few hours to several days and is often aggravated by physical activity or movement.
- Nausea and Vomiting:
- Nausea is a frequent symptom, and in some cases, it may lead to vomiting. This is exacerbated by the dizziness or vertigo that can occur during the attack.
- Sensitivity to Light and Sound:
- Photophobia (sensitivity to light) and phonophobia (sensitivity to sound) are common during the headache phase.
- These sensitivities often force individuals to seek out dark, quiet environments to find relief.
1.3 Postdrome (Migraine Hangover)
After the headache phase, many individuals experience lingering symptoms during the postdrome phase, sometimes called the “migraine hangover.” These can last for hours or days and include:
- Fatigue: Feeling exhausted or drained after the migraine attack.
- Cognitive Impairment: Mental fog, difficulty concentrating, and problems with memory or word retrieval.
- Residual Dizziness: Some individuals may continue to feel off-balance or dizzy even after the primary symptoms have resolved.
2. Triggers of Migraine with Brainstem Aura
Similar to other types of migraines, migraine with brainstem aura can be triggered by various internal and external factors. Identifying and avoiding these triggers is a key part of managing the condition.
2.1 Stress and Anxiety
- Emotional stress is one of the most common triggers for migraine with brainstem aura. Sudden increases in stress or prolonged anxiety can lead to an attack.
2.2 Hormonal Changes
- Hormonal fluctuations, particularly in women, can trigger this type of migraine. This includes changes in estrogen levels during menstruation, pregnancy, or menopause.
2.3 Sleep Disturbances
- Both lack of sleep and excessive sleep can trigger migraine with brainstem aura. Irregular sleep patterns, such as sleeping too little or too much, are particularly problematic.
2.4 Dietary Triggers
- Certain foods and drinks can provoke migraines, including:
- Caffeine (excessive consumption or withdrawal)
- Alcohol (particularly red wine and beer)
- Aged cheeses, processed meats, and foods high in tyramine
- Monosodium glutamate (MSG), found in some processed foods
2.5 Environmental Triggers
- Bright lights, loud noises, and strong odors can trigger migraines with brainstem aura. These sensory inputs can overstimulate the brain and lead to an attack.
2.6 Changes in Weather
- Sudden changes in weather, particularly shifts in barometric pressure, temperature, or humidity, are known triggers for many types of migraines, including migraine with brainstem aura.
3. Mechanisms of Migraine with Brainstem Aura
The exact cause of migraine with brainstem aura is not entirely understood, but several theories explain how this type of migraine affects the brain. Like other migraines, it likely involves complex changes in brain chemistry, blood flow, and electrical activity.
3.1 Cortical Spreading Depression (CSD)
- Cortical spreading depression is a wave of electrical activity that moves across the brain’s cortex and brainstem, causing a temporary disruption in normal function. This wave of neuronal activity is followed by a period of decreased activity, which may explain the aura symptoms, particularly those involving the brainstem.
- In migraine with brainstem aura, this wave spreads to the back of the brain, affecting the brainstem and causing the distinct symptoms of this migraine type.
3.2 Brainstem Dysfunction
- The brainstem is responsible for controlling essential functions like balance, coordination, and sensory processing. During an MBA attack, the brainstem may become overactive or dysregulated, leading to symptoms such as vertigo, ataxia, and dysarthria.
- It is also thought that disruptions in brainstem pathways that control pain and sensory processing contribute to the migraine headache itself.
3.3 Vascular Changes
- Changes in blood flow to the posterior parts of the brain, including the brainstem and cerebellum, may play a role in triggering the symptoms of migraine with brainstem aura.
- These vascular changes may cause temporary ischemia (reduced blood flow) in certain parts of the brain, leading to symptoms such as double vision, balance issues, and slurred speech.
3.4 Neurotransmitter Imbalances
- Fluctuations in neurotransmitters like serotonin, which regulate pain, mood, and sensory processing, are a key factor in many types of migraines. In migraine with brainstem aura, abnormal serotonin levels may contribute to the aura symptoms as well as the headache itself.
4. Diagnosis of Migraine with Brainstem Aura
Diagnosing migraine with brainstem aura can be challenging, as its symptoms often mimic other serious conditions like stroke, transient ischemic attacks (TIAs), or epilepsy. Diagnosis typically involves a thorough evaluation of the patient’s medical history, a physical and neurological examination, and, in some cases, diagnostic testing to rule out other conditions.
4.1 Diagnostic Criteria (ICHD-3)
The International Classification of Headache Disorders (ICHD-3) provides specific criteria for diagnosing migraine with brainstem aura:
- At least two attacks with aura symptoms originating from the brainstem, such as vertigo, dysarthria, tinnitus, double vision, or ataxia.
- No motor weakness, as hemiplegic migraine involves motor weakness, which is not present in migraine with brainstem aura.
- Headache characteristics: The headache typically follows the aura and includes at least two of the following: unilateral location, throbbing or pulsating quality, moderate or severe intensity, and aggravation by routine physical activity.
- No other diagnosis: Other neurological conditions, like stroke, must be ruled out through diagnostic testing.
4.2 Imaging Studies
- MRI or CT Scan: Magnetic resonance imaging (MRI) or computed tomography (CT) scans are often performed to rule out other conditions like strokes, brain tumors, or structural abnormalities in the brain. These scans are usually normal in individuals with migraine with brainstem aura.
- EEG (Electroencephalogram): This test measures electrical activity in the brain and can help rule out seizure disorders that may cause similar symptoms.
4.3 Differential Diagnosis
Because symptoms of migraine with brainstem aura overlap with other serious neurological conditions, the following must be ruled out:
- Stroke or TIA (Transient Ischemic Attack): A stroke or TIA can cause sudden vertigo, balance problems, and speech difficulties similar to those seen in MBA. However, the onset of a migraine with brainstem aura is usually gradual, and the symptoms resolve completely.
- Epilepsy: Some forms of epilepsy can cause temporary loss of balance, vision problems, and confusion, but these episodes are typically shorter and not followed by a migraine headache.
5. Treatment of Migraine with Brainstem Aura
Treatment for migraine with brainstem aura focuses on both acute management of symptoms and prevention of future attacks. Due to the involvement of the brainstem, care must be taken when selecting medications to avoid complications.
5.1 Acute Treatment
- Nonsteroidal Anti-inflammatory Drugs (NSAIDs): Over-the-counter pain relievers like ibuprofen or naproxen can help manage mild to moderate headaches associated with migraine with brainstem aura.
- Antiemetics: Medications like metoclopramide or prochlorperazine can help control nausea and vomiting, especially if dizziness or vertigo is severe.
- Triptans and Ergotamines: These migraine-specific medications are typically used to stop an acute migraine attack. However, triptans and ergotamines are generally not recommended for migraine with brainstem aura because they constrict blood vessels, which can pose a risk in individuals with brainstem involvement.
5.2 Preventive Treatment
For individuals with frequent or severe migraine with brainstem aura attacks, preventive medications may be necessary to reduce the frequency and severity of migraines.
- Calcium Channel Blockers: Verapamil is commonly used to prevent migraines, including those with brainstem aura, by stabilizing blood flow to the brain.
- Beta-blockers: Propranolol is another preventive medication that can reduce the frequency of attacks.
- Anticonvulsants: Medications like topiramate or valproate may help prevent migraines by reducing abnormal brain activity.
- Antidepressants: Tricyclic antidepressants (e.g., amitriptyline) or selective serotonin reuptake inhibitors (SSRIs) may be effective in managing both migraines and any associated mood or anxiety disorders.
5.3 Lifestyle Modifications
- Trigger Avoidance: Identifying and avoiding common triggers like stress, hormonal changes, and certain foods or environmental factors can help prevent attacks.
- Regular Sleep Schedule: Maintaining a consistent sleep schedule is important, as irregular sleep patterns can trigger migraine with brainstem aura.
- Stress Management: Techniques like mindfulness meditation, yoga, and cognitive-behavioral therapy (CBT) can help reduce stress, a common trigger for migraines.
Conclusion
Migraine with brainstem aura is a rare and complex form of migraine that involves significant neurological symptoms affecting balance, coordination, vision, speech, and hearing. It can be frightening due to the overlap with symptoms of more serious conditions like stroke or seizure, but with proper diagnosis and management, individuals can find relief and reduce the frequency of attacks. Treatment includes both acute symptom management and preventive strategies, often requiring a combination of medications and lifestyle changes to improve quality of life for those affected by this challenging condition.
