Definition and Overview
Migraine with aura is Before or at the same time the headache starts It is a migraine with temporary neurological symptoms. It is classified as code 1.2 in the International Classification of Headache (ICHD-3). This applies to approximately 25-30% of all migraine patients.
Auras reflect temporary changes in brain function. Like a flashing light or numbness New types of abnormal sensations (benign symptoms), A type in which part of the field of vision is lost or the senses are dulled. It is divided into (negative symptoms).
Types of Prodromal Symptoms
Eye-related symptoms (visual aura)
Visual signs are the most common form. It accounts for more than 90% of all prodromal symptoms. Typical symptoms are as follows:
- Flashing lights or sparkling dots before your eyes
- zigzag shaped beam of light
- A phenomenon where part of the visual field is not visible (scotoma)
- A phenomenon in which an object appears distorted
Visual auras usually start in one visual field and It gradually widens over 5 to 20 minutes. This diffusion pattern causes changes in the electrical activity of brain neurons. A phenomenon that spreads like a wave at a speed of 2 to 5 mm per minute. coincides in time.
Sensory symptoms (sensory aura)
Sensory auras are the second most common form. It occurs in approximately 30-54% of patients. Numbness or stinging sensation that starts in one hand After going up the arm It is typical for it to spread to the same side of the face, lips, and tongue. As with visual signs, over several minutes It is characterized by gradual progress.
Speech symptoms (speech signs)
Speech signs occur in approximately 10% of cases. Difficulty remembering words, slurred speech, Reading and writing become temporarily difficult. Language signs do not appear in isolation It often occurs following visual or sensory symptoms.
Cause: Changes in electrical activity of brain neurons
The cause of aura symptoms is changes in the electrical activity of brain neurons. It is a phenomenon that spreads like a wave. The brain cortex (cerebral cortex) surface at a speed of 2 to 5 mm per minute. The excitement of the nerve cells spreads, This is followed by a period in which neural activity temporarily stops.
When this phenomenon occurs, the balance of chemicals around nerve cells is disrupted. Temporarily broken, In functional brain imaging (functional MRI) studies Progression of visual symptoms and Temporal and spatial consistency of cerebral blood flow changes was confirmed.
This electrical change connects the brain and head blood vessels. It is believed to cause headaches by stimulating the trigeminal nerve. After this phenomenon occurred in animal experiments, Increased secretion of pain-related substances (CGRP) was observed.
Diagnostic criteria
According to the International Classification of Headache (ICHD-3) The diagnostic criteria for typical migraine with aura are as follows.
- Two or more attacks meeting the criteria below:
- One or more of the following recurring (reversible) prodromal symptoms:
- visual symptoms
- sensory symptoms
- speech or language impairment
- motor symptoms
- brainstem symptoms
- retinal symptoms
- 3 or more of the following apply
- One or more symptoms that gradually spread over 5 minutes or more
- Two or more symptoms occur consecutively
- Each aura lasts 5 to 60 minutes.
- One or more aura symptoms present on only one side
- One or more aura symptoms are positive (new sensations occur)
- Headache within 60 minutes of symptom onset or at the same time
- Not better explained by another condition
relationship with stroke
If you have migraine with aura, your risk of stroke (cerebral infarction) increases. In a large-scale research analysis The risk of stroke in patients with migraine with aura is It was found to be approximately 2.16 times higher than that of the general public. On the other hand, in migraines without aura, No increased risk of stroke was identified.
The risk is highest in women under 45 years of age; Taking oral contraceptives (about 7 times) If you combine smoking (approximately 9 times), the risk increases significantly. Therefore, for women with migraine with aura, The use of oral contraceptives containing estrogen is not recommended. Quitting smoking is strongly recommended.
Diseases that require differentiation
Premonitory symptoms of migraine with aura are: Symptoms may be similar to those of other diseases, so differentiation is necessary.
- Transient ischemic attack (TIA): Occurs suddenly and causes
- While it gets most severe within a few minutes,
- Symptoms progress slowly over 5 minutes or more.
- Epileptic seizures: progress rapidly within seconds to minutes.
- Cerebrovascular malformation: Confirmed through brain imaging.
When prodromal symptoms first appeared, If it is different from the existing pattern or persists for more than 60 minutes You must seek medical attention from a specialist.