The Relationship Of Central Sensitization And Brain-derived Neurotrophic Factor To Primary Dysmenorrhea And Pain Caused By Endometriosis

Part 1 The influence of primary dysmenorrhea to the brain functional network and gray matter volume at resting-stateObjectivesThe data of resting-state functional magnetic resonance imaging (fMRI) are collected from patients with severe primary dysmenorrhea and healthy women during menstrual period in order to observe whether there are changes of structure and function in some brain regions of patients with severe dysmenorrhea for a long time, and to explore the mechanism of dysmenorrhea related to central nerve system, which will guide the clinical treatment and provide theoretical basis for new target of treatment.MethodsA total of ten patients with severe primary dysmenorrhea and ten healthy women were recruited. The data of resting-state fMRI and high-resolution structural imaging were acquired from subjects during menstrual period, using a Philips 3.0T magnetic resonance scanner. Difference in amplitude of low frequency fluctuation between two groups was analyzed by REST running on Matlab R2012. Group independent component analysis was performed by GIFT running on Matlab R2011b. Two networks including anterior and posterior default-mode networks were chosen. The processing steps of high-resolution structural imaging including segmentation, spatial normalization and smooth were performed by voxel-based morphometry within SPM8. The differences of functional connectivity and gray matter volume within 2 resting-state networks between two groups were investigated, using the statistical analysis within SPM8.ResultsQualified resting-state fMRI data were acquired from all 20 subjects. (1) There was no significant difference in gray matter volume between two groups during menstrual period. (2) In comparison with healthy group, the dysmenorrhea group showed significantly increased brain function in the left precuneus, while significantly decreased brain function in the bilateral medial prefrontal lobes. (3) In comparison with healthy group, the dysmenorrhea group showed significantly increased functional connectivity in the left prefrontal lobe of anterior default-mode network, while significantly decreased functional connectivity in the right primary somatosensory cortex of posterior default-mode network.ConclusionsThere were changes of brain function and functional connectivity at resting-state in some brain regions related to pain in patients with primary dysmenorrhea during the painful menstrual period. Central sensitization may participate in the occurrence and development of primary dysmenorrhea. Changes of brain function may occur before changes of brain structure in patients with long-time dysmenorrhea.Part 2 The relationship of brain-derived neurotrophic factor and pain caused by endometriosisObjectivesTo compare the expression levels of brain-derived neurotrophic factor (BDNF) and specific marker for nerve, fiber called protein gene product 9.5 (PGP9.5) in the ectopic and eutopic endometrium of patients with endometriosis with and without pain, in order to analyse the relationship of BDNF and the occurrence and pain of endometriosis.MethodsEctopic and eutopic endometrium were collected from patients with ovarian endometriosis (25 cases) and myoma (25 cases), respectively, from October 2014 to September 2015 at the department of obstetrics and gynecology in Peking Union Medical College Hospital. The distribution and expression levels of BDNF and PGP9.5 were evaluated in the ectopic and eutopic endometrium of patients (13 cases with pain and 12 cases without pain) with ovarian endometriosis, and the eutopic endometrium of patients with painless myoma by immunohistochemistry.ResultsThere was no significant difference in age and gravidity and parity history in groups of patients with and without endometriosis. BDNF was detected positively in the epithelium and stroma of endometrium for the first time. Meanwhile, the level of BDNF in the epithelium was significantly higher than that in the stroma. There was no significant difference in the level of BDNF in follicular and luteal phases of endometrium in patients without endometriosis. The level of BDNF in the ectopic endometrium was significantly higher than that in the eutopic endometrium of patients with endometriosis. Besides, the level of BDNF in the endometrium of patients with endometriosis was significantly higher than that in the endometrium of patients without endometriosis. There was no significant difference in the level of BDNF in the ectopic and eutopic endometrium of endometriosis in groups of patients with and without pain. PGP9.5 was not detected in the ovarian ectopic endometrium. Although without significant difference, the positive rate of PGP9.5 in the endometrium of patients with endometriosis was higher than that in the endometrium of patients without endometriosis (20% vs.8%).ConclusionsIt was confirmed for the first time that BDNF was expressed in the epithelium and stroma of ectopic and eutopic endometrium of ovarian endometriosis, and the level of BDNF in the aforementioned position was significantly higher than that in the eutopic endometrium of patients without endometriosis, which indicated that BDNF may participate in the occurrence and development of endometriosis.Part 3 Clinical characteristics and management experience of unexpected uterine sarcoma after myomectomyObjectivesTo identify the prevalence of unexpected uterine sarcoma after myomectomy for presumed leiomyoma and compare clinical outcomes after primary myomectomy with and without power morcellation.MethodsIn a retrospective study, a review was undertaken of the medical records of patients who had unexpected uterine sarcoma after myomectomy with and without power morcellation at Peking Union Medical College Hospital, Beijing, China, between January 2009 and December 2013.ResultsAmong 4248 patients who underwent myomectomy for presumed leiomyoma,9 (0.21%) had unexpected uterine sarcoma (1 [0.02%] had leiomyosarcoma; 8 [0.19%] endometrial stromal sarcoma). The malignancy was identified in 5 (0.16%) of 3068 women who were treated by laparoscopy with power morcellation and 4 (0.34%) of 1180 who underwent laparotomy (P>0.05). All nine patients were alive after a mean follow-up of 31.20 months in the laparoscopy group and 40.50 months in the laparotomy group.ConclusionsThe overall incidence of unexpected uterine sarcoma after myomectomy was low. Incidental power morcellation of unexpected uterine sarcoma seemed to cause no increase in sarcoma dissemination in short term.