Cerebral gray matter volume in patients with chronic migraine: correlations with clinical features

Abstract

BackgroundTo date, few MRI studies have been performed in patients affected by chronic migraine (CM), especially in those without medication overuse. Here, we performed magnetic resonance imaging (MRI) voxel-based morphometry (VBM) analyses to investigate the gray matter (GM) volume of the whole brain in patients affected by CM. Our aim was to investigate whether fluctuations in the GM volumes were related to the clinical features of CM.MethodsTwenty untreated patients with CM without a past medical history of medication overuse underwent 3-Tesla MRI scans and were compared to a group of 20 healthy controls (HCs). We used SPM12 and the CAT12 toolbox to process the MRI data and to perform VBM analyses of the structural T1-weighted MRI scans. The GM volume of patients was compared to that of HCs with various corrected and uncorrected thresholds. To check for possible correlations, patients’ clinical features and GM maps were regressed.ResultsInitially, we did not find significant differences in the GM volume between patients with CM and HCs (p < 0.05 corrected for multiple comparisons). However, using more-liberal uncorrected statistical thresholds, we noted that compared to HCs, patients with CM exhibited clusters of regions with lower GM volumes including the cerebellum, left middle temporal gyrus, left temporal pole/amygdala/hippocampus/pallidum/orbitofrontal cortex, and left occipital areas (Brodmann areas 17/18). The GM volume of the cerebellar hemispheres was negatively correlated with the disease duration and positively correlated with the number of tablets taken per month.ConclusionNo gross morphometric changes were observed in patients with CM when compared with HCs. However, using more-liberal uncorrected statistical thresholds, we observed that CM is associated with subtle GM volume changes in several brain areas known to be involved in nociception/antinociception, multisensory integration, and analgesic dependence. We speculate that these slight morphometric impairments could lead, at least in a subgroup of patients, to the development and continuation of maladaptive acute medication usage.Electronic supplementary materialThe online version of this article (10.1186/s10194-017-0825-z) contains supplementary material, which is available to authorized users.

The Chronic Migraine Brain: What Have We Learned From Neuroimaging?

“…Several studies (29,30,34) demonstrated that chronic migraine is also associated with morphometric alterations of brain areas known to be involved in pain modulation and in the different aspects of pain processing. Regions of increased and decreased gray matter volume, including the brainstem, cerebellum, basal ganglia, amygdala, frontal, temporal and occipital areas, have been found in chronic migraine patients compared to controls (29,30,34).…”

“…Whether these functional and structural alterations are the consequence of the recurrence of headache attacks or might predispose to chronic migraine is still a matter of debate. Some studies demonstrated functional (14,20) and structural (30,33,34) plasticity of nociceptive brain areas that are linked to the headache attack frequency and disease duration. Repetitive headache attacks can remodel the pain network, thus increasing the susceptibility to the onset of further attacks and leading to chronic central sensitization.…”

Genetic Screening of Plasticity Regulating Nogo-Type Signaling Genes in Migraine

“…Results from these investigations have identified differences between control and migraine brains with regard to resting state activity and structure of gray and white matter. Differences have been detected in the frontal lobes, corpus callosum, the limbic system, cerebellum, the brainstem and nociceptive regions, although findings are not consistent across studies [22,24,25,[27][28][29][30][31][32][33][34][35][36]. In addition to regional differences, cortical thickness has been reported to differ between migraine patients and controls, and even correlate to attack frequency [37].…”

“…A substantial number of experiments have been conducted to analyze potential differences between the migraine brain and the healthy brain. Brain activity and morphology have been scrutinized with different techniques, such as electrophysiology, electroencephalography, magnetoencephalography, magnetic resonance imaging (MRI) and positron emission tomography [21][22][23][24][25][26][27]. Results from these investigations have identified differences between control and migraine brains with regard to resting state activity and structure of gray and white matter.…”

Haemodynamic Activity Characterization of Resting State Networks by Fractal Analysis and Thalamocorticalmorpho functional Integrity in Chronic Migraine

“…This study is part of a more comprehensive one in which the same patients underwent multiple neuroimaging tests during the same experimental session. The healthy subjects in this study were published elsewhere [24][25][26]. The criteria for exclusion were the presence of neurological comorbidities other than migraine, obvious psychiatric disorders, endocrinological disorders, autoimmune or connective tissue disorders, and arterial hypertension.…”