From the Guidelines
Migraine aura tunnel vision is primarily caused by cortical spreading depression, a wave of electrical activity that disrupts the brain's visual cortex function, leading to temporary visual disturbances. This phenomenon is characterized by a wave of hyperexcitation followed by inhibition of neurons in the visual cortex, resulting in the aura symptoms [ 1 ]. The visual cortex is responsible for processing visual information, and the disruption caused by cortical spreading depression leads to the typical aura symptoms, including tunnel vision.
Key Characteristics of Migraine with Aura
- At least two attacks that fulfill specific criteria, including one or more fully reversible aura symptoms, such as visual, sensory, or speech and language symptoms [ 1 ]
- The aura symptoms must last between 5-60 minutes and can be accompanied by or followed by a headache within 60 minutes [ 1 ]
- The aura is typically unilateral, meaning it affects one side of the brain, and can be positive, meaning it involves an increase in sensory input [ 1 ] ### Treatment and Prevention While medications like triptans may be beneficial during the aura phase, prevention through trigger avoidance and prophylactic medications, such as those listed in Table 4 of the study [ 2 ], is often more effective for those who regularly experience migraine with aura. It is essential to note that some medications, such as combined hormonal contraceptives, are contraindicated in women with migraine with aura due to the increased risk of stroke [ 2 ].
Important Considerations
- The visual disturbances caused by migraine aura tunnel vision are temporary and reversible, with vision returning to normal as the wave of depression passes [ 1 ]
- Patients may benefit from keeping a headache diary to track their symptoms and identify potential triggers [ 2 ]
- A comprehensive treatment plan, including lifestyle modifications, trigger avoidance, and prophylactic medications, can help reduce the frequency and severity of migraine with aura attacks [ 2 ]
From the Research
Mechanism of Migraine Causing Aura Tunnel Vision
- The exact mechanism of migraine causing aura tunnel vision is not fully understood, but it is believed to be related to cortical spreading depression (CSD) 3.
- CSD is a wave of abnormal electrical activity that spreads across the brain, causing a range of symptoms including visual disturbances, sensory changes, and speech and language problems.
- Visual aura is the most common type of aura, occurring in over 90% of patients, and can cause symptoms such as tunnel vision, blind spots, and zigzag patterns 3.
- The symptoms of aura are thought to be caused by the activation of nerve cells in the brain, which can lead to changes in blood flow and the release of chemical messengers such as serotonin 4.
- The use of triptans, such as sumatriptan, has been shown to be effective in treating migraine attacks, but may be less effective in patients with aura compared to those without aura 5.
Treatment Options
- Treatment options for migraine with aura include acute therapies such as triptans and ergotamines, as well as preventive therapies such as beta-blockers, calcium channel blockers, and antiepileptic drugs 6, 4.
- Non-pharmacological therapies, such as neuromodulation and biobehavioural approaches, may also be effective in managing migraine symptoms 7.
- The choice of treatment will depend on the individual patient's symptoms, medical history, and preferences, and may involve a combination of different therapies 7.