Larger volume and different functional connectivity of the amygdala in women with premenstrual syndrome.

OBJECTIVES: To assess structural and functional changes of the amygdala due to premenstrual syndrome (PMS) using magnetic resonance imaging (MRI). METHODS: Twenty PMS patients and 21 healthy control (HC) subjects underwent a 6-min resting-state fMRI scan during the luteal phase as well as scanning high-resolution T1-weighted images. Subcortical amygdala-related volume and functional connectivity (FC) were estimated between the two groups. Each subject completed a daily record of severity of problems (DRSP) to measure the severity of clinical symptoms. RESULTS: Greater bilateral amygdalae volumes were found in PMS patients compared with HC subjects, and PMS patients had increased FC between the amygdala and certain regions of the frontal cortex (e.g. medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), right precentral gyrus), the right temporal pole and the insula, as well as decreased FC between the bilateral amygdalae and the right orbitofrontal cortex and right hippocampus. The strength of FC between the right amygdala and right precentral gyrus, left ACC and left mPFC were significantly and positively correlated with DRSP scores in PMS patients. CONCLUSIONS: Our findings may improve our understanding of the neural mechanisms involved in PMS. KEY POINTS: • Functional and structural MRI used to explore amygdala in PMS patients. • Aberrant amygdala structural and functional connectivity were found in PMS patients. • Amygdala strength FC was positively correlated with individual clinical symptom scores.

Hippocampal fractional amplitude of low-frequency fluctuation and functional connectivity changes in premenstrual syndrome.

PURPOSE: To investigate differences in hippocampal activity between premenstrual syndrome (PMS) patients and healthy controls, to elucidate the neural mechanisms of PMS. MATERIALS AND METHODS: Twenty female patients with PMS (PMS group) and 21 healthy controls (HC group) underwent a single-shot gradient-recalled echo planar imaging (EPI) sequence scan during the luteal phase in 3.0 Tesla MRI. Spontaneous neural activity in hippocampus (HIPP) was measured by fractional amplitude of low-frequency fluctuation (fALFF). Functional connectivity (FC) was used to examine the neural networks of PMS patients by selecting the abnormal HIPP as the seed region. All participants completed a daily record of severity of problems (DRSP) questionnaire to measure the severity of clinical symptoms. RESULTS: Results from a two-sample t-test showed increased left HIPP fALFF in the PMS group compared with the HC group (P = 0.042), while there was no between-group difference of fALFF in the right HIPP (P = 0.1011). A secondary analysis using a two-sample t-test with the left HIPP as the seed region, the results revealed that the PMS group exhibited increased FC between the left HIPP and left medial prefrontal cortex (mPFC), left posterior cingulate cortex (PCC), right middle cingulate cortex (MCC), and bilateral precentral cortex (PC), while decreased FC between the left HIPP and right orbitofrontal cortex (OFC). Moreover, the PMS group exhibited higher DRSP scores, which were positively correlated (r = 0.64, P = 0.003) with FC between the left HIPP and mPFC during the luteal phase. CONCLUSION: Altered spontaneous neural activity and connectivity of left HIPP may be involved in PMS. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:545-553.

Altered fractional amplitude of low frequency fluctuation in premenstrual syndrome: A resting state fMRI study.

BACKGROUND: Premenstrual syndrome (PMS) is becoming highly prevalent among female and is characterized by emotional, physical and behavior symptoms. Previous evidence suggested functional dysregulation of female brain was expected to be involved in the etiology of PMS. The aim of present study was to evaluate the alterations of spontaneous brain activity in PMS patients based on functional magnetic resonance imaging (fMRI). METHODS: 20 PMS patients and 21 healthy controls underwent resting-state fMRI scanning during luteal phase. All participants were asked to complete a prospective daily record of severity of problems (DRSP) questionnaire. RESULTS: Compared with healthy controls, the results showed that PMS patients had increased fALFF in bilateral precuneus, left hippocampus and left inferior temporal cortex, and decreased fALFF in bilateral anterior cingulate cortex (ACC) and cerebellum at luteal phase. Moreover, the DRSP scores of PMS patients were negatively correlated with the mean fALFF in ACC and positively correlated with the fALFF in precuneus. LIMITATIONS: (1) the study did not investigate whether or not abnormal brain activity differences between groups in mid-follicular phase, and within-group changes. between phases.(2) it was relatively limited sample size and the participants were young; (3) fALFF could not provide us with more holistic information of brain network;(4) the comparisons of PMS and premenstrual dysphoric disorder (PMDD) were not involved in the study. CONCLUSIONS: The present study shows abnormal spontaneous brain activity in PMS patients revealed by fALFF, which could provide neuroimaging evidence to further improve our understanding of the underlying neural mechanism of PMS.

Abnormal Spontaneous Brain Activity in Women with Premenstrual Syndrome Revealed by Regional Homogeneity.

Background: Previous studies have revealed that the etiologies of premenstrual syndrome (PMS) refer to menstrual cycle related brain changes. However, its intrinsic neural mechanism is still unclear. The aim of the present study was to assess abnormal spontaneous brain activity and to explicate the intricate neural mechanism of PMS using resting state functional magnetic resonance imaging (RS-fMRI). Materials and Methods: The data of 20 PMS patients (PMS group) and 21 healthy controls (HC group) were analyzed by regional homogeneity (ReHo) method during the late luteal phase of menstrual cycle. In addition, all the participants were asked to complete a daily record of severity of problems (DRSP) questionnaire. Results: Compared with HC group, the results showed that PMS group had increased ReHo mainly in the bilateral precuneus, left inferior temporal cortex (ITC), right inferior frontal cortex (IFC) and left middle frontal cortex (MFC) and decreased ReHo in the right anterior cingulate cortex (ACC) at the luteal phase. Moreover, the PMS group had higher DRSP scores, and the DRSP scores positively correlated with ReHo in left MFC and negatively correlated with ReHo in the right ACC. Conclusion: Our results suggest that abnormal spontaneous brain activity is found in PMS patients and the severity of symptom is specifically related to the left MFC and right ACC. The present findings may be beneficial to explicate the intricate neural mechanism of PMS.