Research indicates that migraines are associated with abnormalities of the brain present at birth and other abnormalities which develop in due course. Migraines are throbbing, intense headaches, sometimes together with nausea, vomiting and light sensitivity. Some individuals have auras, sensory or visual function changes which come before or take place at the time of the migraine. According to the WHO, over 300 million individuals worldwide experience migraines.
Prior studies on individuals with migraine have demonstrated atrophy of the brain’s cortical regions associated with pain processing, possibly as a result of chronic stimulation of those areas. The cortical region is outer layer of the brain, or the cortex. Many of these studies have relied on voxel-based morphometry, providing estimates of the cortical volume of the brain. Researchers made use of a different approach in this study: a surface-based MRI technique for measuring cortical thickness.
Surface area abnormalities and cortical thickness were assessed in individuals with migraine, 2 components of cortical volume providing complementary and different bits of information. There is a dramatic increase of cortical surface area during late fetal development as a result of cortical folding, while there is a dynamic change of cortical thickness during the entire life span as a result of development and disease.
MRI (magnetic resonance imaging) was used to acquire T2-weighted and 3-D T1-weighted brain images from 63 individuals with migraine and 18 healthy individuals. Making use of special software and statistical analysis, surface area and cortical thickness was estimated and this was correlated with the radiologic and clinical characteristics of the individuals.
In comparison to controls, individuals with migraine showed reduced surface and cortical thickness area in regions associated with pain processing.
The most significant outcome of the research was that cortical abnormalities which take place in individuals with migraine are a consequence of the balance between an intrinsic predisposition, as indicated by modification of cortical surface area, and processes related to disease, as indicated by abnormalities of cortical thickness. Accurate cortical abnormality measurements could help characterize individuals with migraine better and improve understanding of the pathophysiological processes which underlie the condition.