Can dynamic contrast-enhanced MRI help researchers understand migraines?

Dynamic contrast-enhanced (DCE) MRI can help measure the permeability of the blood-brain barrier (BBB) in areas of the brain associated with migraines, potentially providing insight into the debilitating headaches and other neurovascular disorders.

“Alterations in permeability of the blood-brain barrier (BBB) are reported to be associated with chronic pain,” wrote co-lead author Yeon Soo Kim, with Seoul National University Hospital’s Department of Radiology in South Korea, and colleagues. “Although measurement of BBB breakdown remains challenging because of a lack of fast imaging techniques, objective measuring, and imaging parameter modeling, it would be a valuable aid in the diagnosis and measurement of the therapeutic response in neurovascular disorders.”

To investigate the relationship between permeability of the BBB in brain areas associated with migraine, the team prospectively performed DCE MRI in 56 patients from September 2016 to December 2017. All patients underwent imaging after gadobutrol was administered and were then separated into a migraine group (35 patients) and healthy controls (21).

Researchers coregistered the region-of-interest brain maps with corresponding pharmacokinetic parameter maps that included the volume transfer constant (Ktrans) and the fractional plasma volume (Vp), calculating their mean values of corresponding total volume of interest.

Patients with migraine showed lower local blood plasma volume fraction in a brain region thought to be associated with migraines compared to healthy controls, measuring a median of 0.27 mL/100 g and 0.39 mL/100g, respectively. Lower fractional plasma volume was also correlated with a more intense headache in those with migraines, according to the research published in Radiology.

“These observations suggest that BBB impairment in the amygdala may relate to pathophysiologic change in individuals with migraine,” Kim et al. wrote.

The team noted they could not directly correlate the relationship between BBB integrity and metabolic demand, therefore they could not “reliably conclude that the mean Vp in the left amygdala is entirely reflecting the metabolic changes in migraine.”

“This work by Kim et al has the potential to change the identification of migraine from a diagnosis of exclusion to a widely available imaging biomarker. However, we need to proceed with caution,” wrote Timothy J. Carroll, PhD, and Daniel Thomas Ginat, MD, each with the University of Chicago’s Department of Radiology, in a related editorial.

For one, the pair noted, this was a single-center study performed at a “high-end, prestigious” research institute, and the technique must be easy to implement in other radiology departments. Additionally, the use of gadolinium-based MRI contrast remains an issue and must be considered due to the chronic nature of migraines.