Personalized migraine therapies could be on horizon

By Mark Waghorn via SWNS

Personalized therapies for migraine could soon be a reality, according to new research.

Scientists have discovered specific changes in the brains of sufferers - opening the door to better drugs.

Using MRI scans, they have shown that people with severe migraines have larger spaces in one region of the brain.

The blinding headaches blight the lives of eight million Britons. The exact cause is unknown.

They are thought to be the result of abnormal brain activity temporarily affecting nerve signals, chemicals and blood vessels.

"In people with chronic migraine and episodic migraine without aura, there are significant changes in the perivascular spaces of a brain region called the centrum semiovale. These have never been reported before," said co-author Wilson Xu, a student at the University of Southern California.

Perivascular spaces are fluid-filled spaces surrounding blood vessels in the brain. They are most commonly located in the basal ganglia and white matter of the cerebrum, and along the optic tract.

They are affected by several factors, including abnormalities at the blood-brain barrier and inflammation.

Enlarged perivascular spaces can be a signal of underlying blood vessel disease.

"Perivascular spaces are part of a fluid clearance system in the brain. Studying how they contribute to migraine could help us better understand the complexities of how migraines occur," Xu said.

The discovery could lead to medications or other treatments that target them, say the US team.

A state of the art scanning technique called ultra-high-field 7T MRI (magnetic resonance imaging) compared tiny vessel changes in different types of migraine.

"To our knowledge, this is first study using ultra-high-resolution MRI to study microvascular changes in the brain due to migraine, particularly in perivascular spaces," Xu said.

"Because 7T MRI is able to create images of the brain with much higher resolution and better quality than other MRI types, it can be used to demonstrate much smaller changes that happen in brain tissue after a migraine."
 
The study involved 25 participants aged 25 to 60 - ten with chronic migraines, ten with episodic migraines without aura and five age-matched healthy controls.

Statistical analysis revealed the number of enlarged perivascular spaces in an area of white matter called the centrum semiovale was significantly higher in migraine patients. They were also linked to severity.

"We studied chronic migraine and episodic migraine without aura and found that, for both types of migraine, perivascular spaces were bigger in the centrum semiovale," Xu said.

"Although we didn’t find any significant changes in the severity of white matter lesions in patients with and without migraine, these white matter lesions were significantly linked to the presence of enlarged perivascular spaces.

"This suggests that changes in perivascular spaces could lead to future development of more white matter lesions."

Lesions 'light up' on MRI. Any bleeds were also measured. Clinical data such as disease duration and severity, symptoms, presence of aura and side of headache was collected, too.

The researchers suggest the findings show migraine is associated with disruption to the glymphatic system within the brain.

This is a waste clearance process that utilizes perivascular channels to help eliminate soluble proteins and metabolites from the central nervous system.

Whether such changes affect migraine development or result from migraine is unknown.

Further studies with larger case populations will better establish the relationship between structural changes and migraine development and type.

"The results of our study could help inspire future, larger-scale studies to continue investigating how changes in the brain’s microscopic vessels and blood supply contribute to different migraine types," Xu said.

"Eventually, this could help us develop new, personalized ways to diagnose and treat migraine."

The study was presented at a Radiological Society of North America meeting in Chicago.