When it comes to migraines, some sufferers not only suffer from headaches, but also from so-called aura symptoms. These include visual disturbances that occur before the onset of the headache. So far, however, their specific causes have remained unclear.
In a new study, researchers at the University of California – Los Angeles Health Sciences (UCLA) have now investigated whether changes in the structure and function of the blood vessels in the retina may play a role in the visual disturbances that occur during a migraine attack. The results are published in the specialist journal “Headache – The Journal of Head an Face Pain”.
Many suffer from migraines
Migraine is a relatively widespread complaint, which, according to the Institute for Quality and Efficiency in Health Care (IQWiG), affects around 14 percent of women and around seven percent of men in this country.
Migraine attacks are often accompanied by visual symptoms, although the cause of these visual disturbances has so far remained unclear, explains the research team at UCLA.
Blood circulation in the retina examined
The researchers now tried to determine whether changes in blood flow in the retina might play a role using so-called optical coherence tomography angiography (OCTA).
“OCTA is a fast, non-invasive imaging method that can be used to visualize the retinal microvasculature with high spatial resolution in a clinical environment,” explain the researchers.
A total of 37 people with migraine and aura symptoms, 30 people with migraine without aura symptoms and 20 healthy people as a control group were examined using OCTA. In the migraine patients, the retinal vascular system was examined during and between attacks.
Association with migraines found
The researchers then tried to identify changes in the structure and function of the retinal vascular system that are related to the visual impairments. They found that a significant reduction in blood flow in the retina occurs during migraine attacks.
The altered blood flow was detectable in both migraines with aura symptoms and migraines without aura symptoms, the team reports. However, those affected with aura symptoms showed even less blood flow in certain areas of the retina.
In addition, according to the researchers, the blood flow in the retina on the same side was changed more strongly in the case of one-sided headaches.
New biomarker for migraines
Overall, the study results could provide information about why some sufferers develop visual symptoms of migraine, and the retinal microvascular blood flow could also serve as a biomarker for migraine attacks, the researchers conclude. (fp)