Brain Structure And Function In Patients With Primary Dysmenorrhea In Resting State

Primary dysmenorrhea（PDM）refers to the pain without organic lesions,which is a common gynecological disease in women of childbearing age.With the development of neuroimaging technology,it has been found that the brain structure and function of patients with primary dysmenorrhea are abnormal,but the specific pain mechanism of primary dysmenorrhea is not clear.In this paper,based on magnetic resonance technology,morphological analysis and functional connection method were used to study the abnormalities of brain structure and function in patients with primary dysmenorrhea in the resting state.The main research results of this paper are as follows:1.For the brain structure of patients with primary dysmenorrhea,Freesurfer image software was used to analyze the changes of cortical surface area,gray matter volume and cortical thickness of the subjects.The results showed that patients with primary dysmenorrhea had significant differences in cortical surface area,gray matter volume,and cortical thickness in left inferior occipital gyrus,cuneus,fusiform gyrus,orbital gyrus,right lingual gyrus,occipital gyrus,and superior frontal gyrus than healthy subjects.The abnormalities lasted from menstruation to ovulation.The gray matter volume of the left orbital gyrus was positively correlated with the severity of dysmenorrhea symptom,and the gray matter volume of the left fusiform gyrus was positively correlated with the VAS pain score.Compared with ovulation,the cortical surface area of left middle occipital gyrus,superior frontal gyrus and right inferior orbital gyrus decreased,the gray matter volume of left parahippocampal gyrus decreased,the cortical thickness of left superior frontal gyrus decreased,and the cortical thickness of right anterior cingulate gyrus increased.Moreover,gray matter volume in the left parahippocampal gyrus was positively correlated with luteinizing hormone levels.These results demonstrate that recurrent pain can cause structural changes in the brain.Changes in these brain regions are associated with hormone levels during the menstrual cycle.2.Aiming at the brain function activity of patients with primary dysmenorrhea,we analyzed the difference of brain network functional connection between subjects with dysmenorrhea ang healthy subjects.Compared with healthy subjects,the functional connections between the default mode network and the central control network were enhanced in dysmenorrhea subjects,while the connections between the sensorimotor network and the default mode network and the right frontal parietal control network were weekened.The connection between sensorimotor network and cerebellar network was weakened in dysmenorrhea subjects during ovulation.Seed point based functional connectivity analysis found that patients with primary dysmenorrhea had increased functional connectivity in the left and right insula,medial prefrontal and left parietal gyrus,bilateral superior temporal gyrus and cerebellum,left superior temporal gyrus and right parietal lobule.The changes of these abnormal areas are related to pain regulation,sensorimotor regulation and emotion regulation.This paper studies the brain changes of patients with primary dysmenorrhea from the aspects of brain structure and function.The results showed that there were not only structural changes but also functional changes in patients with primary dysmenorrhea.The areas of structural changes might be consistent with the changes of the resting state network in the corresponding brain regions.This study shows that patients with primary dysmenorrhea can affect the changes of brain structure and function through emotion regulation and long-term dysmenorrhea experience.These findings can increase the understanding of pain mechanism in patients with primary dysmenorrhea and provide new ideas for the treatment of primary dysmenorrhea.