Less arterial expansion than expected

When scans show that the blood vessels do not expand, there must be another reason why the patients get headaches.

Using the latest MRI scan technology, Amin examined the inside and outside of the brain and looked at small arteries during natural attacks.

A total of 19 healthy women with migraine took part in the experiment.

Their brains were scanned while they suffered a severe migraine headache without aura, headaches that are limited to one side of the head.

The scans enabled the researchers to compare the expansions of the blood vessels on the side where the pain was felt with the side where no pain was felt.

“Contrary to what has previously been believed, we found that the arteries on the outside of the skull did not expand during migraine attacks,” says Amin.

“Arteries inside the skull were only slightly expanded on the side where the headache was felt, compared to the other side where no pain was felt.”

Migraine drugs don’t work like we thought they did

The pain-ridden women were then given a popular migraine drug to determine how it affected the arteries.

“We treated the attacks with sumatriptan, which is the most popular migraine drug on the market. And then we made another MRI scan of the brain,” explains Amin.

“Here we observed that the arteries inside the brain remained expanded even after the migraine headache had passed.”

Facts

Migraine sufferers usually experience a severe headache, which feels like a throbbing pain at the front or on one side of the head. This pain is usually accompanied by several autonomic nervous system symptoms.

Migraine pain is further aggravated by movement, for instance if you bend your head forward or climb stairs.

It is therefore not uncommon to hear complaints from migraine patients who worry that their head is about to explode. The new study shows that such worries are unfounded.

This suggests that the old theory that sumatriptan works by narrowing the arteries may not be right after all. The new findings prepare the ground for studies into why sumatriptan still works even though the beneficial effect does not appear to be linked to the narrowing of arteries.

New theory: pain caused by extra-sensitive nerve fibres

The new discovery has paved the way for a new theory: migraine pain occurs because the nerve fibres around the blood vessels become extra sensitive.

This means that the blood’s normal pulsation in an artery feels like an intense, throbbing pain. If this is the case, it is as yet uncertain why it is so.

“Our findings are of great importance to our understanding of migraine headaches and future research on migraines,” says Amin.

“At the same time, the findings can also be used to reassure migraine sufferers who worry that their arteries are about to explode during an attack. They’re not.”

(sciencenordic.com)

(Picture source:unsplash.com)