MRI Scans Reveal Brain Abnormalities in Migraine Patients

Migraines are intense, throbbing headaches, sometimes accompanied by nausea, vomiting, and sensitivity to light. Some patients experience auras, a change in visual or sensory function that precedes or occurs during the migraine. More than 300 million people suffer from migraines worldwide, according to the World Health Organization (Geneva, Switzerland).

A lot of that research has depended on voxel-based morphometry technology, which provides estimations of the brain’s cortical volume. In the new study, Italian researchers used a different tool: surface-based magnetic resonance imaging (MRI) to gauge cortical thickness. “For the first time, we assessed cortical thickness and surface area abnormalities in patients with migraine, which are two components of cortical volume that provide different and complementary pieces of information,” said Massimo Filippi, MD, director of the neuroimaging research unit at the University Ospedale San Raffaele and professor of neurology at the University Vita-Salute’s San Raffaele Scientific Institute (Milan, Italy). “Indeed, cortical surface area increases dramatically during late fetal development as a consequence of cortical folding, while cortical thickness changes dynamically throughout the entire life span as a consequence of development and disease.”

Dr. Filippi and colleagues used MRI scanning to capture T2-weighted and three-dimensional (3D) T1-weighted brain images from 63 migraine patients and 18 healthy control participants. Utilizing customized software and statistical analysis, they estimated cortical thickness and surface area and correlated it with the patients’ clinical and radiologic characteristics.

Migraine patients, in comparison to controls, showed reduced cortical thickness and surface area in regions related to pain processing. There was only slight anatomic overlap of cortical thickness and cortical surface area abnormalities, with cortical surface area irregularities being more pronounced and distributed than cortical thickness abnormalities. The presence of aura and white matter hyperintensities—regions of high intensity on MRI that appear to be more common in individuals with migraines—was related to the regional distribution of cortical thickness and surface area abnormalities, but not to disease duration and attack frequency.

“The most important finding of our study was that cortical abnormalities that occur in patients with migraine are a result of the balance between an intrinsic predisposition, as suggested by cortical surface area modification, and disease-related processes, as indicated by cortical thickness abnormalities,” Dr. Filippi said. “Accurate measurements of cortical abnormalities could help characterize migraine patients better and improve understanding of the pathophysiological processes underlying the condition.”

Further studies are required to clarify the meaning of cortical abnormalities in the pain processing areas of migraine patients, according to Dr. Filippi. “Whether the abnormalities are a consequence of the repetition of migraine attacks or represent an anatomical signature that predisposes to the development of the disease is still debated,” he said. “In my opinion, they might contribute to make migraine patients more susceptible to pain and to an abnormal processing of painful conditions and stimuli.”

The researchers are performed a longitudinal study of the patient group to clarify if their cortical abnormalities are stable or apt to worsen over the course of the disease. They are also studying the effects of treatments on the observed modifications of cortical folding and examining pediatric patients with migraine to assess whether the abnormalities represent a biomarker of the disease.

Related Links:
University Vita-Salute’s San Raffaele Scientific Institute