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Introduction: This study aimed to explore the functional connectivity of the primary visual cortex (V1) in children with anisometropic amblyopia by using the resting-state functional connectivity analysis method and determine whether anisometropic amblyopia is associated with changes in brain function., Methods: Functional magnetic resonance imaging (fMRI) data were obtained from 16 children with anisometropia amblyopia (CAA group) and 12 healthy children (HC group) during the resting state. The Brodmann area 17 (BA17) was used as the region of interest, and the functional connection (FC) of V1 was analyzed in both groups. A two-sample t test was used to analyze the FC value between the two groups. Pearson's correlation was used to analyze the correlation between the mean FC value in the brain function change area of the CAA group and the best corrected visual acuity (BCVA) of amblyopia. p < 0.05 was considered statistically significant., Results: There were no significant differences in age and sex between the CAA and HC groups (p > 0.05). Compared to the HC group, the CAA group showed lower FC values in BA17 and the left medial frontal gyrus, as well as BA17 and the left triangle inferior frontal gyrus. Conversely, the CAA group showed higher FC values in BA17 and the left central posterior gyrus. Notably, BCVA in amblyopia did not correlate with the area of change in mean FC in the brain function of the CAA group., Conclusion: Resting-state fMRI-based functional connectivity analysis indicates a significant alteration in V1 of children with anisometropic amblyopia. These findings contribute additional insights into the neuropathological mechanisms underlying visual impairment in anisometropic amblyopia., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Objective: Serum hormone deficiencies during menopause transition may affect spontaneous brain activity and global cognition. The purpose of this study was to explore the differences in spontaneous brain activity between premenopausal and perimenopausal women, and to investigate the associations between spontaneous brain activity, serum hormone levels and global cognition., Methods: Thirty-two premenopausal women (47.75 ± 1.55 years) and twenty-five perimenopausal women (51.60 ± 1.63 years) underwent resting-state functional MRI (fMRI) scan. Clinical information including Mini-Mental State Examination (MMSE), levels of estradiol (E2), free testosterone, progesterone, prolactin, follicle-stimulating hormone and luteinizing hormone were measured. Regional homogeneity (ReHo) was used to evaluate spontaneous brain activity alterations between perimenopausal and premenopausal women. Correlation analysis was used to investigate the associations between brain functional alterations and clinical measures in perimenopausal group., Results: The results demonstrated increased ReHo value in the right lingual gyrus (LG) and decreased ReHo value in the right superior frontal gyrus (SFG) in perimenopausal women compared with premenopausal women. In perimenopausal group, ReHo of the right LG showed a negative correlation with level of E2 (r = -0.586, p = 0.002), ReHo of the right SFG showed a positive correlation with level of E2 (r = 0.470, p = 0.018) and MMSE (r = 0.614, p = 0.001)., Conclusions: The results demonstrated that women approaching menopause suffered from altered functions in brain regions related to cognitive function, working memory, the results also revealed a direct association between levels of E2 and brain functions in perimenopausal women., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 He, Guo, Qiu, An and Lu.)

Purpose: Functional changes have been observed between diseased and healthy subjects, and functional brain atlases derived from healthy populations may fail to reflect functional characteristic of the diseased brain. Therefore the aim of this study was to generate a visual atlas based on functional connectivity from primary open-angle glaucoma (POAG) patients and to prove the applicability of the visual atlas in functional connectivity and network analysis., Methods: Functional magnetic resonance images were acquired from 36 POAG patients and 20 healthy controls. Two data-driven approaches, K-means and Ward clustering algorithms, were adopted for visual cortices parcellation. Dice coefficient and adjusted Rand index were used to assess reproducibility of the two approaches. Homogeneity index, silhouette coefficient, and network properties were adopted to assess functional validity for the data-driven approaches and frequently used brain atlas. Graph theoretical analysis was adopted to investigate altered network patterns in POAG patients based on data-driven visual atlas., Results: Parcellation results demonstrated asymmetric patterns between left and right hemispheres in POAG patients compared with healthy controls. In terms of evaluating metrics, K-means performed better than Ward clustering in reproducibility. Data-driven parcellations outperformed frequently used brain atlases in terms of functional homogeneity and network properties. Graph theoretical analysis revealed that atlases generated by data-driven approaches were more conducive in detecting network alterations between POAG patients and healthy controls., Conclusions: Our findings suggested that POAG patients experienced functional alterations in the visual cortices. Results also highlighted the necessity of data-driven atlases for functional connectivity and functional network analysis of POAG brain.

Purpose: To investigate brain morphological alterations of high-tension glaucoma patients and explore the association between brain morphological changes and elevated intraocular pressure., Methods: Thirty-six patients with high-tension glaucoma and 20 healthy controls were collected and underwent structural MRI scan. Surface-based morphometry and voxel-based morphometry were applied to assess cortical thickness and subcortical gray matter volume of the enrolled subjects. The association between brain morphometry and intraocular pressure was assessed by partial correlation., Results: Compared with healthy controls, high-tension glaucoma patients showed decreased cortical thickness in the bilateral superior temporal gyrus, bilateral superior parietal gyrus, bilateral lateral occipital gyrus, left fusiform gyrus, left medial orbitofrontal gyrus, right precentral gyrus, and right superior frontal gyrus (p < 0.05). High-tension glaucoma patients also showed reduced gray matter volume in the right hippocampus, bilateral putamen, and bilateral thalamus (p < 0.05). In addition, brain morphological correlates of mean intraocular pressure were found in the left rostral middle frontal gyrus, right precentral gyrus, and left postcentral gyrus in high-tension glaucoma group (p < 0.05)., Conclusion: High-tension glaucoma patients experienced morphological reduction in the visual and nonvisual areas throughout the entire brain. Elevated intraocular pressure may contribute to the reduction of cortical thickness in certain areas in the progression of the disease.

Purpose: To evaluate the effects of high intraocular pressure (IOP) on central nervous system in patients with high-tension glaucoma (HTG) by using resting-state functional magnetic resonance imaging (rs-fMRI)., Methods: Thirty-six patients with HTG and twenty age- and gender-matched healthy controls (HCs) were recruited and underwent IOP measurement and rs-fMRI scan. The whole brain regional homogeneity (ReHo) value was calculated among the enrolled subjects. Two-sample t tests with permutation test and threshold-free cluster enhancement was performed between HTG group and HCs. Correlation analyses between IOP and ReHo values were conducted., Results: Compared with HCs, HTG group showed increased ReHo values in the left lobule 8 of cerebellar hemisphere, left lobule 4 and 5 of cerebellar hemisphere and left fusiform gyrus (FG) (p < 0.05). HTG group showed decreased ReHo value in the left middle frontal gyrus (MFG) (p < 0.05). Intraocular pressure of the left eye in HTG group experienced a significant positive correlation with ReHo value of the left FG (r = 0.370, p = 0.026), IOP of the right eye in HTG group showed a significant negative correlation with ReHo value in the left MFG (r = -0.421, p = 0.011)., Conclusion: Resting-state fMRI ReHo analyses associated elevated IOP with abnormal regional activity in several brain regions related to higher visual function and visual memory consolidation. High-tension glaucoma patients also showed diminished integration of visual information and cerebellar function. These results may provide imaging support for pathophysiological research of HTG and may reveal new targets for the accurate treatment of HTG., (© 2019 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Background: Perimenopause is associated with increased risk of depression, vasomotor symptoms, and sexual dysfunction., Aims: To explore the effect of sex hormones on the functional connectivity (FC) of different brain regions related to sexual function in perimenopausal women., Methods: 32 premenopausal women (mean age, 47.75 ± 1.55 years) and 25 perimenopausal women (mean age, 51.60 ± 1.63 years) underwent sex hormone level measurements and resting-state fMRI., Main Outcome Measures: Serum levels of sex hormones, including prolactin (PRL), follicle-stimulating hormone (FSH), luteotropic hormone (LH), estradiol (E2), free testosterone (free-T), and progesterone (P), were measured. 10 brain regions related to sexual function were selected according to a meta-analysis, and FCs of the selected regions of interest were calculated as Pearson's correlation coefficient., Results: Compared with premenopausal women, perimenopausal women showed increased FC between the right area 13 (A13&#95;r) and the right medial superior frontal gyrus (mSFG), between the left dorsal granular insula (dIg&#95;L) and the right superior frontal gyrus (SFG) (Gaussian random field-corrected at the voxel level, P < .001, and cluster level, P < .025). Furthermore, the PRL level was negatively correlated with the FC of A13&#95;R with the right mSFG and the FC of dIg&#95;L with the right SFG., Clinical Translation: These findings may be applicable to assessing brain dysfunction with FC changes in women approaching menopause., Strengths & Limitations: This study is the first to evaluate a direct relationship between sex hormone levels and brain FC changes in women approaching menopause. Sexual function was not assessed, which may weaken the conclusions related to sexual function., Conclusions: The results show that women approaching menopause suffered from aberrant intrinsic FC in regions related to sexual function, and reveal a direct relationship between serum sex hormone levels and FC changes related to sexual function. Lu W, Guo W, Cui D, et al. Effect of Sex Hormones on Brain Connectivity Related to Sexual Function in Perimenopausal Women: A Resting-State fMRI Functional Connectivity Study. J Sex Med 2019;16:711-720., (Copyright © 2019 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: A 3D printed geometric phantom was developed that can be scanned with computed tomography (CT) and magnetic resonance imaging (MRI) to measure the geometric distortion and determine the relevant dose changes. Materials and Methods: A self-designed 3D printed photosensitive resin phantom was used, which adopts grid-like structures and has 822 1 cm2 squares. The scanning plan was delivered by three MRI scanners: the Elekta Unity MR-Linac 1.5T, GE Signa HDe 1.5T, and GE Discovery-sim 750 3.0T. The geometric distortion comparison was concentrated on two 1.5T MRI systems, whereas the 3.0T MRI was used as a supplemental experiment. The most central transverse images in each dataset were selected to demonstrate the plane distortion. Some mark points were selected to analyze the distortion in the 3D direction based on the plane geometric distortion. A treatment plan was created with the off-line Monaco system. Results: The distortion increases gradually from the center to the outside. The distortion range is 0.79 ± 0.40 mm for the Unity, 1.31 ± 0.56 mm for the GE Signa HDe, and 2.82 ± 1.48 mm for the GE Discovery-sim 750. Additionally, the geometric distortion slightly affects the actual planning dose of the radiotherapy. Conclusion: Geometric distortion increases gradually from the center to the outside. The distortion values of the Unity were smaller than those of the GE Signa HDe, and the Unity has the smallest geometric distortion. Finally, the Unity's dose variation best matched with the standard treatment plan. [ABSTRACT FROM AUTHOR]

The present study aimed to explore brain morphological alterations associated with age and sex hormone levels between premenopausal and perimenopausal women using magnetic resonance imaging (MRI) T1‐weighted structural images. Thirty‐two premenopausal women aged (mean ± SD) 47.75 ± 1.55 years and twenty‐five recently perimenopausal women aged 51.60 ± 1.63 years were evaluated for sex hormone levels, including prolactin, follicle‐stimulating hormone, luteinising hormone, oestradiol, free testosterone and progesterone. A 3.0‐Tesla MRI scanner was utilised to acquire T1 images. Voxel‐based morphometry (VBM) was used to evaluate changes in grey matter volume between the two groups. The general linear model was applied with false discovery rate correction for between group voxel‐wise statistics. Spearman partial correlation analyses were conducted between age, sex hormone levels and regions of grey matter volume showing significant differences between the two groups. The VBM analysis revealed that age and menopause per se lead to grey matter volume reduction in certain brain structures. These structural changes might be potential causes of sexual dysfunction, nervous system degeneration and depression, which need to be examined in future studies. Our findings might provide evidence and guide future research in understanding the menopausal transition. [ABSTRACT FROM AUTHOR]

• The current clinical presentations of ADHD fail to reflect the underlying neurobiological mechanism. • We discovered two neurosubtypes of ADHD which were different from clinical phenotypes. • The two neurosubtypes of ADHD exhibited differences in clinical profiles and brain structural and functional patterns. • The current neurosubtypes could facilitate the understanding of neuropathological and neurobiological mechanism of ADHD. Clinical and etiological variability of attention deficit hyperactivity disorder (ADHD) presents an obstacle to understand the disorder. The aim of this study was to disentangle the heterogeneity of ADHD using neuroimaging and a semi-supervised machine learning algorithm. We collected brain structural and functional magnetic resonance imaging (MRI) data and clinical profiles of 183 children with ADHD and 396 neurotypical controls from 7 independent sites. We also used an external validation set with 750 subjects. We adopted a semi-supervised clustering method to subtype ADHD by regional volumetric measures of gray matter, white matter, and fractional amplitude of low frequency fluctuation (fALFF). In addition, split sample test, leave-one-site-out test and external validation were applied to evaluate the reproducibility and stability of ADHD subtypes. Two stable and reproducible neurosubtypes of ADHD were disclosed, which were proved by the split-sample test and leave-one-site-out validation. The structural and functional patterns of ADHD subtypes were also stable in the external validation set. The current two neurosubtypes differed in clinical manifestations and volumetric gray matter, white matter volume and fALFF patterns. The current neurosubtypes of ADHD which were different from clinical phenotypes could facilitate understanding the underlying neuropathological and neurobiological mechanism of the disorder. [ABSTRACT FROM AUTHOR]