Structural brain characteristics of epilepsy patients with comorbid migraine without aura

Abstract Background Migraine is a common bi-directional comorbidity of epilepsy and there is possible potential complex interaction between the two diseases. Until now there is no study of brain morphology analysis of them. The use of VBM, SBM and SCN are helpful to improve the accuracy of detection of morphological changes. Methods Thirty patients of epilepsy with comorbid migraine without aura (EM) were included in our study, simultaneously, 20 healthy controls (HC), 30 epilepsy controls (EC) without migraine were recruited as control. We used voxel-based morphometry (VBM), surface-based morphometry (SBM), and structural covariance network (SCN) analysis to compare differences in gray matter volume, cortical thickness, and global level and local level graph theory indexes between the EM, EC, and HC groups to investigate structural brain changes in EM patients. Results VBM analysis showed that the EM group had gray matter atrophy in the right temporal pole compared with the HC group (p < 0.001, false discover rate correction). Furthermore, the headache duration in the EM group was negatively correlated with the gray matter volume of the right temporal pole (p < 0.05). SBM analysis showed cortical atrophy in the left insula, left posterior cingulate gyrus, left postcentral gyrus, left middle temporal gyrus, and left fusiform gyrus in EM compared with the HC group (p < 0.001, family wise error correction). We found a positive correlation between headache frequency and the cortical thickness of the left middle temporal gyrus (p < 0.05). SCN analysis revealed that no differences in global parameters between the three groups. The AUC of nodal betweenness centrality in the right postcentral gyrus was decreased in the EM group compared with the HC group (p < 0.001, FDR correction), and the AUC of the nodal degree in the right fusiform gyrus was decreased in the EM group compared with the EC group (p < 0.001, FDR correction). Conclusion We found clear structural brain changes in EM patients compared to HC. Migraine attacks may have potential effects on brain structure in epilepsy patients. Meanwhile, brain structural changes may be an important factor for the development of epilepsy with comorbid migraine. Further studies are needed to investigate the structural changes of epilepsy with comorbid migraine without aura.