Publications by authors named "Zhentao Zuo"

51 Publications

A neural decoding algorithm that generates language from visual activity evoked by natural images.

Neural Netw 2021 Aug 12;144:90-100. Epub 2021 Aug 12.

The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, China. Electronic address:

Transforming neural activities into language is revolutionary for human-computer interaction as well as functional restoration of aphasia. Present rapid development of artificial intelligence makes it feasible to decode the neural signals of human visual activities. In this paper, a novel Progressive Transfer Language Decoding Model (PT-LDM) is proposed to decode visual fMRI signals into phrases or sentences when natural images are being watched. The PT-LDM consists of an image-encoder, a fMRI encoder and a language-decoder. The results showed that phrases and sentences were successfully generated from visual activities. Similarity analysis showed that three often-used evaluation indexes BLEU, ROUGE and CIDEr reached 0.182, 0.197 and 0.680 averagely between the generated texts and the corresponding annotated texts in the testing set respectively, significantly higher than the baseline. Moreover, we found that higher visual areas usually had better performance than lower visual areas and the contribution curve of visual response patterns in language decoding varied at successively different time points. Our findings demonstrate that the neural representations elicited in visual cortices when scenes are being viewed have already contained semantic information that can be utilized to generate human language. Our study shows potential application of language-based brain-machine interfaces in the future, especially for assisting aphasics in communicating more efficiently with fMRI signals.
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http://dx.doi.org/10.1016/j.neunet.2021.08.006DOI Listing
August 2021

Neural Mechanism Underlying the Sleep Deprivation-Induced Abnormal Bistable Perception.

Cereb Cortex 2021 Jul 28. Epub 2021 Jul 28.

Beijing Key Laboratory of Applied Experimental Psychology, School of Psychology, Beijing Normal University, Beijing 100875, China.

Quality sleep is vital for physical and mental health. No matter whether sleep problems are a consequence of or contributory factor to mental disorders, people with psychosis often suffer from severe sleep disturbances. Previous research has shown that acute sleep deprivation (SD) can cause transient brain dysfunction and lead to various cognitive impairments in healthy individuals. However, the relationship between sleep disturbance and bistable perception remains unclear. Here, we investigated whether the bistable perception could be affected by SD and elucidated the functional brain changes accompanying SD effects on bistable perception using functional magnetic resonance imaging. We found that the 28-h SD resulted in slower perceptual transitions in healthy individuals. The reduced perceptual transition was accompanied by the decreased activations in rivalry-related frontoparietal areas, including the right superior parietal lobule, right frontal eye field, and right temporoparietal junction. We speculated that SD might disrupt the normal function of these regions crucial for bistable perception, which mediated the slower rivalry-related perceptual transitions in behavior. Our findings revealed the neural changes underlying the abnormal bistable perception following the SD. It also suggested that SD might offer a new window to understand the neural mechanisms underlying the bistable perception.
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http://dx.doi.org/10.1093/cercor/bhab235DOI Listing
July 2021

A dual-channel language decoding from brain activity with progressive transfer training.

Hum Brain Mapp 2021 Jul 27. Epub 2021 Jul 27.

The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.

When we view a scene, the visual cortex extracts and processes visual information in the scene through various kinds of neural activities. Previous studies have decoded the neural activity into single/multiple semantic category tags which can caption the scene to some extent. However, these tags are isolated words with no grammatical structure, insufficiently conveying what the scene contains. It is well-known that textual language (sentences/phrases) is superior to single word in disclosing the meaning of images as well as reflecting people's real understanding of the images. Here, based on artificial intelligence technologies, we attempted to build a dual-channel language decoding model (DC-LDM) to decode the neural activities evoked by images into language (phrases or short sentences). The DC-LDM consisted of five modules, namely, Image-Extractor, Image-Encoder, Nerve-Extractor, Nerve-Encoder, and Language-Decoder. In addition, we employed a strategy of progressive transfer to train the DC-LDM for improving the performance of language decoding. The results showed that the texts decoded by DC-LDM could describe natural image stimuli accurately and vividly. We adopted six indexes to quantitatively evaluate the difference between the decoded texts and the annotated texts of corresponding visual images, and found that Word2vec-Cosine similarity (WCS) was the best indicator to reflect the similarity between the decoded and the annotated texts. In addition, among different visual cortices, we found that the text decoded by the higher visual cortex was more consistent with the description of the natural image than the lower one. Our decoding model may provide enlightenment in language-based brain-computer interface explorations.
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http://dx.doi.org/10.1002/hbm.25603DOI Listing
July 2021

Altered cerebral perfusion and microstructure in advanced Parkinson's disease and their associations with clinical features.

Neurol Res 2021 Jul 27:1-10. Epub 2021 Jul 27.

Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.

Objective: To explore the whole cerebral perfusion and microstructure alteration patterns in Parkinson's disease (PD) and the associations of these patterns with clinical features.

Methods: Forty-one subjects [20 PD patients and 21 healthy controls (HCs)] underwent arterial spin labeling (ASL), diffusion tensor imaging (DTI) and 3D T1-weighted imaging (T1WI) MRI. The cerebral blood flow (CBF) of the whole brain and the fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD) and mean diffusivity (MD) of subcortical and cerebellar regions were measured and compared between groups. Pearson's correlation was calculated between MRI measurements and clinical features [Unified Parkinson's Disease Rating Scale (UPDRS), UPDRS III, Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and olfactory test scores].

Results: Compared to HCs, PD patients showed lower CBF in the frontal, parietal and temporal lobes but higher CBF in bilateral hippocampi, red nuclei, right substantia nigra, thalamus and most cerebellar regions. The MD in the right thalamus and several regions in the cerebellum increased in PD compared to HCs. In PD patients, the total UPDRS, UPDRS III, MoCA, MMSE and olfactory test scores were related to FA or CBF in cerebellum. (all p < 0.05).

Conclusion: Hypoperfusion in cortical regions, together with hyperperfusion in subcortical and cerebellar regions may be the characteristic perfusion pattern in advanced PD patients. The microstructures of the right thalamus and cerebellum were changed in PD patients. The cognitive, motor and olfactory performance of PD patients is closely related to the perfusion and microstructure of the brain, especially the cerebellum.
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http://dx.doi.org/10.1080/01616412.2021.1954842DOI Listing
July 2021

The brain basis of handwriting deficits in Chinese children with developmental dyslexia.

Dev Sci 2021 Jul 20:e13161. Epub 2021 Jul 20.

Center for Brain Disorders and Cognitive Sciences, Shenzhen University, Shenzhen, China.

Abundant behavioral studies have demonstrated high comorbidity of reading and handwriting difficulties in developmental dyslexia (DD), a neurological condition characterized by unexpectedly low reading ability despite adequate nonverbal intelligence and typical schooling. The neural correlates of handwriting deficits remain largely unknown; however, as well as the extent that handwriting deficits share common neural bases with reading deficits in DD. The present work used functional magnetic resonance imaging to examine brain activity during handwriting and reading tasks in Chinese dyslexic children (n = 18) and age-matched controls (n = 23). Compared to controls, dyslexic children exhibited reduced activation during handwriting tasks in brain regions supporting sensory-motor processing (including supplementary motor area and postcentral gyrus) and visual-orthography processing (including bilateral precuneus and right cuneus). Among these regions, the left supplementary motor area and the right precuneus also showed a trend of reduced activation during reading tasks in dyslexics. Moreover, increased activation was found in the left inferior frontal gyrus and anterior cingulate cortex in dyslexics, which may reflect more efforts of executive control to compensate for the impairments of motor and visual-orthographic processing. Finally, dyslexic children exhibited aberrant functional connectivity among brain areas for cognitive control and sensory-motor processes during handwriting tasks. Together, these findings suggest that handwriting deficits in DD are associated with functional abnormalities of multiple brain regions implicated in motor execution, visual-orthographic processing, and cognitive control, providing important implications for the diagnosis and treatment of dyslexia.
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http://dx.doi.org/10.1111/desc.13161DOI Listing
July 2021

Dexmedetomidine inhibits unstable motor network in patients with primary motor area gliomas.

Aging (Albany NY) 2021 05 25;13(11):15139-15150. Epub 2021 May 25.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China.

Background: Sedative agents such as dexmedetomidine have been found to transiently exacerbate or unmask limb motor dysfunction in patients with eloquent area brain gliomas. The present study aims to investigate whether dexmedetomidine can inhibit motor plasticity in patients with glioma via fMRI.

Methods: 21 patients with brain glioma were prospectively recruited between September 2017 and December 2018. Patients were classified into pre-M1 (primary motor cortex) group (n=9), post-M1 group (n=6), and non-eloquent group (control group) (n=6) according to the tumor position related to M1. The hand movement task-fMRI and resting state fMRI (rs-fMRI) were performed before and after sedation using dexmedetomidine. The lateralization index (LI) of activation voxels and magnitude and the functional connectivity (FC) of motor network were compared before and after sedation and among different groups.

Results: Permanent postoperative motor deficit of the upper limb was found in 5 of 6 patients in the pre-M1 group, and none in other groups ( < .01). Task-fMRI showed the LI of activation volume and activation magnitude at M1 significantly increased only in the pre-M1 group after sedation ( < .05). Rs-fMRI showed 60.0% (27 of 45) FCs of motor network decreased in pre-M1 group after sedation (p[FDR] < .05); whereas there was no FC reduction in post-M1 and control groups (p[FDR] > .05).

Conclusions: In patients with eloquent area gliomas, dexmedetomidine can inhibit the unstable compensative motor plasticity on both task- and rs-fMRI. fMRI may be a promising method for elucidating the effect of sedative agents on motor plasticity.
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http://dx.doi.org/10.18632/aging.203077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8221338PMC
May 2021

Characterization of Cortical and White Matter Microstructural Pathology in Growth Hormone-Secreting Pituitary Adenoma.

Front Oncol 2021 12;11:641359. Epub 2021 Apr 12.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

Background: The growth hormone (GH) and insulin-like-growth factor 1 (IGF-1) axis has long been recognized for its critical role in brain growth, development. This study was designed to investigate microstructural pathology in the cortex and white matter in growth hormone-secreting pituitary adenoma, which characterized by excessive secretion of GH and IGF-1.

Methods: 29 patients with growth hormone-secreting pituitary adenoma (acromegaly) and 31 patients with non-functional pituitary adenoma as controls were recruited and assessed using neuropsychological test, surface-based morphometry, T1/T2-weighted myelin-sensitive magnetic resonance imaging, neurite orientation dispersion and density imaging, and diffusion tensor imaging.

Results: Compared to controls, we found 1) acromegaly had significantly increased cortical thickness throughout the bilateral cortex (pFDR < 0.05). 2) T1/T2-weighted ratio in the cortex were decreased in the bilateral occipital cortex and pre/postcentral central gyri but increased in the bilateral fusiform, insular, and superior temporal gyri in acromegaly (pFDR < 0.05). 3) T1/T2-weighted ratio were decreased in most bundles, and only a few areas showed increases in acromegaly (pFDR < 0.05). 4) Neurite density index (NDI) was significantly lower throughout the cortex and bundles in acromegaly (pTFCE < 0.05). 5) lower fractional anisotropy (FA) and higher mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) in extensive bundles in acromegaly (pTFCE < 0.05). 6) microstructural pathology in the cortex and white matter were associated with neuropsychological dysfunction in acromegaly.

Conclusions: Our findings suggested that long-term persistent and excess serum GH/IGF-1 levels alter the microstructure in the cortex and white matter in acromegaly, which may be responsible for neuropsychological dysfunction.
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http://dx.doi.org/10.3389/fonc.2021.641359DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072046PMC
April 2021

Predicting the location of the preoptic and anterior hypothalamic region by visualizing the thermoregulatory center on fMRI in craniopharyngioma using cold and warm stimuli.

Aging (Albany NY) 2021 03 26;13(7):10087-10098. Epub 2021 Mar 26.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Hypothalamic nuclei in the preoptic and anterior hypothalamic region (POAH) are critically involved in thermoregulation and neuroendocrine regulation and can be displaced by craniopharyngiomas (CPs). We aimed to locate the POAH by visualizing hypothalamic thermoregulation through task-related functional magnetic resonance imaging (fMRI) to guide hypothalamus protection intraoperatively. Nine adult healthy volunteers (HVs) and thirty-two adult primary CP patients underwent task-related fMRI for POAH localization by warm (60° C) and cold (0° C) cutaneous thermoreceptor stimulation. Approach selection and intraoperative POAH protection were performed based on preoperative POAH localization. In all HVs and patients, significant single positive blood oxygen level-dependent (BOLD) signal changes were located in the POAH. The BOLD activity was significantly greater for cold (P=0.03) and warm (P=0.03) stimuli in patients than in HVs. Gross total resection and near-total resection were achieved in 28 (87.5%) and 4 (12.5%) patients, respectively. New-onset diabetes insipidus and new-onset hypopituitarism occurred in 6 patients (18.8%) and 10 patients (31.3%), respectively. Our findings suggest that cutaneous thermoreceptor stimulation could accurately activate the hypothalamic thermoregulatory center and allow POAH localization through task-related fMRI. Preoperative POAH localization could help neurosurgeons protect hypothalamic function intraoperatively. The CP patients were more sensitive to thermal stimulation.
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http://dx.doi.org/10.18632/aging.202766DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8064226PMC
March 2021

The Functional Reorganization of Language Network Modules in Glioma Patients: New Insights From Resting State fMRI Study.

Front Oncol 2021 26;11:617179. Epub 2021 Feb 26.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Background: Prior investigations of language functions have focused on the response profiles of particular brain regions. However, the specialized and static view of language processing does not explain numerous observations of functional recovery following brain surgery. To investigate the dynamic alterations of functional connectivity (FC) within language network (LN) in glioma patients, we explored a new flexible model based on the neuroscientific hypothesis of core-periphery organization in LN.

Methods: Group-level LN mapping was determined from 109 glioma patients and forty-two healthy controls (HCs) using independent component analysis (ICA). FC and mean network connectivity (mNC: l/rFCw, FCb, and FCg) were compared between patients and HCs. Correlations between mNC and tumor volume (TV) were calculated.

Results: We identified ten separate LN modules from ICA. Compared to HCs, glioma patients showed a significant reduction in language network functional connectivity (LNFC), with a distinct pattern modulated by tumor position. Left hemisphere gliomas had a broader impact on FC than right hemisphere gliomas, with more reduced edges away from tumor sites (=0.011). mNC analysis revealed a significant reduction in all indicators of FC except for lFCw in right hemisphere gliomas. These alterations were associated with TV in a double correlative relationship depending on the tumor position across hemispheres.

Conclusion: Our findings emphasize the importance of considering the modulatory effects of core-periphery mechanisms from a network perspective. Preoperative evaluation of changes in LN caused by gliomas could provide the surgeon a reference to optimize resection while maintaining functional balance.
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http://dx.doi.org/10.3389/fonc.2021.617179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7953055PMC
February 2021

Brain volume and perfusion asymmetry in temporal lobe epilepsy with and without hippocampal sclerosis.

Neurol Res 2021 Apr 15;43(4):299-306. Epub 2020 Dec 15.

Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.

: To detect and compare the features of interictal perfusion and volume asymmetry between temporal lobe epilepsy (TLE) patients with and without hippocampal sclerosis (HS).: Sixty-one TLE patients (mean age 28.4 ± 9.3 years; 28 female/33 male) with unilateral signs of HS (TLE-HS+) and 25 TLE patients (mean age 29.8 ± 8.0 years; 17 female/8 male) without HS (TLE-HS-) were included. Thirty healthy volunteers served as controls (mean age 26.0 ± 8.7 years; 22 female/8 male). Brain segmentation and volume calculation were performed. Quantitative cerebral blood flow (CBF) values were measured based on arterial spin labeling (ASL). The asymmetry indices (AIs) of volume and perfusion were calculated.: TLE-HS+ (adjusted = 0.001) and TLE-HS- patients (adjusted = 0.006) had significantly higher hippocampal perfusion AIs than controls. TLE-HS+ and TLE-HS- had similar hippocampal perfusion AIs (adjusted = 1.00). TLE-HS+ had higher hippocampal volume AIs than TLE-HS- and controls (adjusted P < 0.001). TLE-HS- and controls had similar hippocampal volume AIs (adjusted = 1.00). All (100%) TLE-HS+ patients had positive hippocampal perfusion or volume AIs. No significant correlation between the AIs of hippocampal perfusion and volume was found in both TLE-HS+( = 0.894) and TLE-HS- ( = 0.106) patients. TLE-HS+ patients demonstrated more extensive whole-brain asymmetry of both perfusion and volume than TLE-HS- patients.: TLE-HS+ and TLE-HS- patients have different patterns of whole-brain perfusion and volume asymmetry. Hippocampal perfusion asymmetry was revealed in both TLE-HS+ and TLE-HS- patients.
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http://dx.doi.org/10.1080/01616412.2020.1853988DOI Listing
April 2021

Deep Natural Image Reconstruction from Human Brain Activity Based on Conditional Progressively Growing Generative Adversarial Networks.

Neurosci Bull 2021 Mar 22;37(3):369-379. Epub 2020 Nov 22.

The MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, 610054, China.

Brain decoding based on functional magnetic resonance imaging has recently enabled the identification of visual perception and mental states. However, due to the limitations of sample size and the lack of an effective reconstruction model, accurate reconstruction of natural images is still a major challenge. The current, rapid development of deep learning models provides the possibility of overcoming these obstacles. Here, we propose a deep learning-based framework that includes a latent feature extractor, a latent feature decoder, and a natural image generator, to achieve the accurate reconstruction of natural images from brain activity. The latent feature extractor is used to extract the latent features of natural images. The latent feature decoder predicts the latent features of natural images based on the response signals from the higher visual cortex. The natural image generator is applied to generate reconstructed images from the predicted latent features of natural images and the response signals from the visual cortex. Quantitative and qualitative evaluations were conducted with test images. The results showed that the reconstructed image achieved comparable, accurate reproduction of the presented image in both high-level semantic category information and low-level pixel information. The framework we propose shows promise for decoding the brain activity.
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http://dx.doi.org/10.1007/s12264-020-00613-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954952PMC
March 2021

'When' and 'what' did you see? A novel fMRI-based visual decoding framework.

J Neural Eng 2020 10 13;17(5):056013. Epub 2020 Oct 13.

The Clinical Hospital of Chengdu Brain Science Institute, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China. MOE Key Lab for Neuroinformation; High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, University of Electronic Science and Technology of China, Chengdu 610054, People's Republic of China.

Objective: Visual perception decoding plays an important role in understanding our visual systems. Recent functional magnetic resonance imaging (fMRI) studies have made great advances in predicting the visual content of the single stimulus from the evoked response. In this work, we proposed a novel framework to extend previous works by simultaneously decoding the temporal and category information of visual stimuli from fMRI activities.

Approach: 3 T fMRI data of five volunteers were acquired while they were viewing five categories of natural images with random presentation intervals. For each subject, we trained two classification-based decoding modules that were used to identify the occurrence time and semantic categories of the visual stimuli. In each module, we adopted recurrent neural network (RNN), which has proven to be highly effective for learning nonlinear representations from sequential data, for the analysis of the temporal dynamics of fMRI activity patterns. Finally, we integrated the two modules into a complete framework.

Main Results: The proposed framework shows promising decoding performance. The average decoding accuracy across five subjects was over 19 times the chance level. Moreover, we compared the decoding performance of the early visual cortex (eVC) and the high-level visual cortex (hVC). The comparison results indicated that both eVC and hVC participated in processing visual stimuli, but the semantic information of the visual stimuli was mainly represented in hVC.

Significance: The proposed framework advances the decoding of visual experiences and facilitates a better understanding of our visual functions.
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http://dx.doi.org/10.1088/1741-2552/abb691DOI Listing
October 2020

Evolutional and developmental anatomical architecture of the left inferior frontal gyrus.

Neuroimage 2020 11 18;222:117268. Epub 2020 Aug 18.

Guangdong-Hongkong-Macau Institute of CNS Regeneration and Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou 510632, China; Center for Language and Brain, Shenzhen Institute of Neuroscience, Shenzhen 518057, China. Electronic address:

The left inferior frontal gyrus (IFG) including Broca's area is involved in the processing of many language subdomains, and thus, research on the evolutional and human developmental characteristics of the left IFG will shed light on how language emerges and maturates. In this study, we used diffusion magnetic resonance imaging (dMRI) and resting-state functional MRI (fMRI) to investigate the evolutional and developmental patterns of the left IFG in humans (age 6-8, age 11-13, and age 16-18 years) and macaques. Tractography-based parcellation was used to define the subcomponents of left IFG and consistently identified four subregions in both humans and macaques. This parcellation scheme for left IFG in human was supported by specific coactivation patterns and functional characterization for each subregion. During evolution and development, we found increased functional balance, amplitude of low frequency fluctuations, functional integration, and functional couplings. We also observed higher fractional anisotropy values, i.e. better myelination of dorsal and ventral white matter language pathways during evolution and development. We assume that the resting-state functional connectivity and task-related coactivation mapping are associated with hierarchical language processing. Our findings have shown the evolutional and human developmental patterns of left IFG, and will contribute to the understanding of how the human language evolves and how atypical language developmental disorders may occur.
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http://dx.doi.org/10.1016/j.neuroimage.2020.117268DOI Listing
November 2020

Contrahemispheric Cortex Predicts Survival and Molecular Markers in Patients With Unilateral High-Grade Gliomas.

Front Oncol 2020 23;10:953. Epub 2020 Jul 23.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

Malignant high-grade gliomas are characterized by infiltration and destruction of surrounding brain tissue. Alterations in the contrahemispheric brain structure and their roles that may offer prognostically valuable information have not been investigated in high-grade gliomas. In total, 153 patients with unilateral glioma (low-grade, = 77; high-grade, = 76) and 115 healthy controls (HCs) were recruited and scanned with 3-D T1 imaging. The gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) volume in the contrahemisphere were examined. Partial correlation, logistic regression, and multivariate Cox's regression analyses were performed. The contrahemispheric GM volume (CHGMV) in the high-grade glioma patients was significantly decreased compared to that in the HCs/low-grade gliomas (one-way ANOVA, Bonferroni corrected, < 0.05). The CHGMV is significantly correlated with the WHO grade ( = -0.22, < 0.05) and contrast-enhanced volume ( = -0.33, < 0.01). In the high-grade gliomas, the binary logistic regression revealed that the CHGMV can independently predict isocitrate dehydrogenase 1 (IDH1) and P53 mutations. The survival curves revealed that the patients with a low CHGMV had a shorter overall survival (OS) than the patients with a high CHGMV ( = 0.001). The multivariate Cox's regression analysis showed that a low CHGMV can independently predict unfavorable OS with a hazard ratio of 2.883 ( = 0.035). Volume of the contrahemispheric cortex can be potentially used in clinical practice as an imaging biomarker to predict survival and molecular markers in patients with unilateral high-grade gliomas.
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http://dx.doi.org/10.3389/fonc.2020.00953DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7390929PMC
July 2020

Test-retest reliability and reproducibility of long-label pseudo-continuous arterial spin labeling.

Magn Reson Imaging 2020 11 25;73:111-117. Epub 2020 Jul 25.

Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing 100730, China. Electronic address:

Purpose: Arterial spin labeling MRI can quantify the cerebral blood flow (CBF) without exogenous tracer. However, the variation of arterial transit time across different brain regions introduces bias for measuring local CBF, especially for those subjects with long arterial transit time (ATT). Long post-labeling delay (PLD) or multi-PLD methods could mitigate the problem of heterogenous ATT at the expense of the signal-to-noise ratio (SNR). Long-label ASL might address the low SNR problem by increasing the amount of labeled arterial blood. Thus, we hypothesized that with the same relatively long PLD, long-label pCASL may be more robust and reproducible than standard-label pCASL in population with potentially prolonged ATT. The purpose of the study was to investigate the reliability and reproducibility of long-label pCASL in the whole brain and vascular regions of interest in an elderly population, compared with standard-label pCASL.

Method: Twenty adult volunteers (14 males, 6 females; age, 56.6 ± 17.2 years) were scanned twice on one 3.0 T scanner by standard-label pCASL (label duration (LD) = 1500 ms, PLD = 2000 ms) and long-label pCASL (LD = 3500 ms, PLD = 2000 ms). The intraclass correlation coefficient (ICC), within-subject coefficient of variation (wsCV), random noise and signal coefficient of variation(CoV) were used to assess global and regional reliability and reproducibility. Measurement agreement and difference were compared in different brain regions using correlation coefficient plots and Bland-Altman plots respectively.

Results: CBF value measured by long-label pCASL was overall higher than standard-label pCASL in all ROIs. Long-label pCASL had higher ICC than standard-label pCASL in most ROIs, and lower wsCV, random noise and CoV in all ROIs. Regardless of ASL method used, anterior circulation flow territories (ICC, 0.93-0.97; wsCV, 0.03-0.06) had higher CBF reliability and reproducibility than posterior circulation flow territories (ICC, 0.89; wsCV, 0.06-0.08). In all ROIs, the correlation analysis showed higher test-retest agreement (r > r) and the Bland-Altman plots demonstrated lower measurement difference in long-label pCASL.

Conclusion: The study demonstrated good reliability and reproducibility of long-label pCASL in anterior brain regions in the elderly population. To further improve CBF quantification in a long-ATT population while proper PLD is already used, increasing the label duration may help.
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http://dx.doi.org/10.1016/j.mri.2020.07.010DOI Listing
November 2020

Long short-term memory-based neural decoding of object categories evoked by natural images.

Hum Brain Mapp 2020 10 10;41(15):4442-4453. Epub 2020 Jul 10.

The MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.

Visual perceptual decoding is one of the important and challenging topics in cognitive neuroscience. Building a mapping model between visual response signals and visual contents is the key point of decoding. Most previous studies used peak response signals to decode object categories. However, brain activities measured by functional magnetic resonance imaging are a dynamic process with time dependence, so peak signals cannot fully represent the whole process, which may affect the performance of decoding. Here, we propose a decoding model based on long short-term memory (LSTM) network to decode five object categories from multitime response signals evoked by natural images. Experimental results show that the average decoding accuracy using the multitime (2-6 s) response signals is 0.540 from the five subjects, which is significantly higher than that using the peak ones (6 s; accuracy: 0.492; p < .05). In addition, from the perspective of different durations, methods and visual areas, the decoding performances of the five object categories are deeply and comprehensively explored. The analysis of different durations and decoding methods reveals that the LSTM-based decoding model with sequence simulation ability can fit the time dependence of the multitime visual response signals to achieve higher decoding performance. The comparative analysis of different visual areas demonstrates that the higher visual cortex (VC) contains more semantic category information needed for visual perceptual decoding than lower VC.
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http://dx.doi.org/10.1002/hbm.25136DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7502843PMC
October 2020

Structural plasticity of the bilateral hippocampus in glioma patients.

Aging (Albany NY) 2020 06 5;12(11):10259-10274. Epub 2020 Jun 5.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

This study investigates the structural plasticity and neuronal reaction of the hippocampus in glioma patient pre-surgery. Ninety-nine glioma patients without bilateral hippocampus involvement (low-grade, n=52; high-grade, n=47) and 80 healthy controls with 3D T1 images and resting-fMRI were included. Hippocampal volume and dynamic amplitude of low-frequency fluctuation (dALFF) were analyzed among groups. Relationships between hippocampal volume and clinical characteristics were assessed. We observed remote hippocampal volume increases in low- and high-grade glioma and a greater response of the ipsilateral hippocampus than the contralesional hippocampus. The bilateral hippocampal dALFF was significantly increased in high-grade glioma. Tumor-associated epilepsy and the IDH-1 mutation did not affect hippocampal volume in glioma patients. No significant relationship between hippocampal volume and age was observed in high-grade glioma. The Kaplan-Meier curve and log-rank test revealed that large hippocampal volume was associated with shorter overall survival (OS) compared with small hippocampal volume (p=0.007). Multivariate Cox regression analysis revealed that large hippocampal volume was an independent predictor of unfavorable OS (HR=3.597, 95% CI: 1.160-11.153, p=0.027) in high-grade glioma. Our findings suggest that the hippocampus has a remarkable degree of plasticity in response to pathological stimulation of glioma and that the hippocampal reaction to glioma may be related to tumor malignancy.
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http://dx.doi.org/10.18632/aging.103212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7346025PMC
June 2020

Single-Cell Analysis of Human Retina Identifies Evolutionarily Conserved and Species-Specific Mechanisms Controlling Development.

Dev Cell 2020 05 7;53(4):473-491.e9. Epub 2020 May 7.

John F. Hardesty, MD, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA. Electronic address:

The development of single-cell RNA sequencing (scRNA-seq) has allowed high-resolution analysis of cell-type diversity and transcriptional networks controlling cell-fate specification. To identify the transcriptional networks governing human retinal development, we performed scRNA-seq analysis on 16 time points from developing retina as well as four early stages of retinal organoid differentiation. We identified evolutionarily conserved patterns of gene expression during retinal progenitor maturation and specification of all seven major retinal cell types. Furthermore, we identified gene-expression differences between developing macula and periphery and between distinct populations of horizontal cells. We also identified species-specific patterns of gene expression during human and mouse retinal development. Finally, we identified an unexpected role for ATOH7 expression in regulation of photoreceptor specification during late retinogenesis. These results provide a roadmap to future studies of human retinal development and may help guide the design of cell-based therapies for treating retinal dystrophies.
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http://dx.doi.org/10.1016/j.devcel.2020.04.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8015270PMC
May 2020

Integrative analysis of in vivo recording with single-cell RNA-seq data reveals molecular properties of light-sensitive neurons in mouse V1.

Protein Cell 2020 06 29;11(6):417-432. Epub 2020 Apr 29.

State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Brain-Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.

Vision formation is classically based on projections from retinal ganglion cells (RGC) to the lateral geniculate nucleus (LGN) and the primary visual cortex (V1). Neurons in the mouse V1 are tuned to light stimuli. Although the cellular information of the retina and the LGN has been widely studied, the transcriptome profiles of single light-stimulated neuron in V1 remain unknown. In our study, in vivo calcium imaging and whole-cell electrophysiological patch-clamp recording were utilized to identify 53 individual cells from layer 2/3 of V1 as light-sensitive (LS) or non-light-sensitive (NS) by single-cell light-evoked calcium evaluation and action potential spiking. The contents of each cell after functional tests were aspirated in vivo through a patch-clamp pipette for mRNA sequencing. Moreover, the three-dimensional (3-D) morphological characterizations of the neurons were reconstructed in a live mouse after the whole-cell recordings. Our sequencing results indicated that V1 neurons with a high expression of genes related to transmission regulation, such as Rtn4r and Rgs7, and genes involved in membrane transport, such as Na/K ATPase and NMDA-type glutamatergic receptors, preferentially responded to light stimulation. Furthermore, an antagonist that blocks Rtn4r signals could inactivate the neuronal responses to light stimulation in live mice. In conclusion, our findings of the vivo-seq analysis indicate the key role of the strength of synaptic transmission possesses neurons in V1 of light sensory.
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http://dx.doi.org/10.1007/s13238-020-00720-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7251024PMC
June 2020

Robust functional mapping of layer-selective responses in human lateral geniculate nucleus with high-resolution 7T fMRI.

Proc Biol Sci 2020 04 15;287(1925):20200245. Epub 2020 Apr 15.

State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.

The lateral geniculate nucleus (LGN) of the thalamus is the major subcortical relay of retinal input to the visual cortex. It plays important roles in visual perception and cognition and is closely related with several eye diseases and brain disorders. Primate LGNs mainly consist of six layers of monocular neurons with distinct cell types and functions. The non-invasive measure of layer-selective activities of the human LGN would have broad scientific and clinical implications. Using high-resolution functional magnetic resonance imaging (fMRI) at 7 Tesla (T) and carefully designed visual stimuli, we achieved robust functional mapping of eye-specific and also magnocellular/parvocellular-specific laminar patterns of the human LGN. These laminar patterns were highly reproducible with different pulse sequences scanned on separate days, between different subjects, and were in remarkable consistency with the simulation from high-resolution histology of the human LGNs. These findings clearly demonstrate that 7T fMRI can robustly resolve layer-specific responses of the human LGN. This paves the way for future investigation of the critical roles of the LGN in human visual perception and cognition, as well as the neural mechanisms of many developmental and neurodegenerative diseases.
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http://dx.doi.org/10.1098/rspb.2020.0245DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7211434PMC
April 2020

Perception-to-Image: Reconstructing Natural Images from the Brain Activity of Visual Perception.

Ann Biomed Eng 2020 Sep 13;48(9):2323-2332. Epub 2020 Apr 13.

MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.

The reappearance of human visual perception is a challenging topic in the field of brain decoding. Due to the complexity of visual stimuli and the constraints of fMRI data collection, the present decoding methods can only reconstruct the basic outline or provide similar figures/features of the perceived natural stimuli. To achieve a high-quality and high-resolution reconstruction of natural images from brain activity, this paper presents an end-to-end perception reconstruction model called the similarity-conditions generative adversarial network (SC-GAN), where visually perceptible images are reconstructed based on human visual cortex responses. The SC-GAN extracts the high-level semantic features of natural images and corresponding visual cortical responses and then introduces the semantic features as conditions of generative adversarial networks (GANs) to realize the perceptual reconstruction of visual images. The experimental results show that the semantic features extracted from SC-GAN play a key role in the reconstruction of natural images. The similarity between the presented and reconstructed images obtained by the SC-GAN is significantly higher than that obtained by a condition generative adversarial network (C-GAN). The model we proposed offers a potential perspective for decoding the brain activity of complex natural stimuli.
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http://dx.doi.org/10.1007/s10439-020-02502-3DOI Listing
September 2020

Structural and Functional Alterations in the Contralesional Medial Temporal Lobe in Glioma Patients.

Front Neurosci 2020 20;14:10. Epub 2020 Feb 20.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

Background: The human brain has an extraordinary ability to functionally change or reorganize its structure in response to disease. The aim of this study is to assess the structural and functional plasticity of contralesional medial temporal lobe (MTL) in patients with unilateral MTL glioma.

Methods: Sixty-eight patients with unilateral MTL glioma (left MTL glioma, = 33; right MTL glioma, = 35) and 40 healthy controls were recruited and scanned with 3D T1 MRI and rest-fMRI. We explored the structure of the contralesional MTL using voxel-based morphometry (VBM) and assessed the memory networks of the contralesional hemisphere using resting-state functional connectivity (rs-FC). The association between FC and cognitive function was assessed with partial correlation analysis.

Results: Compared with healthy controls, both patient groups exhibited (1) a large cluster of voxels with gray matter (GM) volume decrease in the contralesional MTL using region of interest (ROI)-based VBM analysis (cluster level < 0.05, FDR corrected); and (2) decreased intrahemispheric FC between the posterior hippocampus (pHPC) and posterior cingulate cortex (PCC) ( < 0.01, Bonferroni corrected). Intrahemispheric FC between the pHPC and PCC was positively correlated with cognitive function in both patient groups.

Conclusion: Using multi-modality brain imaging tools, we found structural and functional changes in the contralesional MTL in patients with unilateral MTL glioma. These findings suggest that the contralesional cortex may have decompensation of structure and function in patients with unilateral glioma, except for compensatory structural and functional adaptations. Our study provides additional insight into the neuroanatomical and functional network changes in the contralesional cortex in patients with glioma.
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http://dx.doi.org/10.3389/fnins.2020.00010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7044242PMC
February 2020

Men and women differ in the neural basis of handwriting.

Hum Brain Mapp 2020 07 24;41(10):2642-2655. Epub 2020 Feb 24.

State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.

There is an ongoing debate about whether, and to what extent, males differ from females in their language skills. In the case of handwriting, a composite language skill involving language and motor processes, behavioral observations consistently show robust sex differences but the mechanisms underlying the effect are unclear. Using functional magnetic resonance imaging (fMRI) in a copying task, the present study examined the neural basis of sex differences in handwriting in 53 healthy adults (ages 19-28, 27 males). Compared to females, males showed increased activation in the left posterior middle frontal gyrus (Exner's area), a region thought to support the conversion between orthographic and graphomotor codes. Functional connectivity between Exner's area and the right cerebellum was greater in males than in females. Furthermore, sex differences in brain activity related to handwriting were independent of language material. This study identifies a novel neural signature of sex differences in a hallmark of human behavior, and highlights the importance of considering sex as a factor in scientific research and clinical applications involving handwriting.
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http://dx.doi.org/10.1002/hbm.24968DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7294055PMC
July 2020

The role of serum growth hormone and insulin-like growth factor-1 in adult humans brain morphology.

Aging (Albany NY) 2020 01 22;12(2):1377-1396. Epub 2020 Jan 22.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

Growth hormone (GH) and its anabolic mediator, insulin-like growth factor-1 (IGF-1), have a critical role in the central nervous system. However, their detailed roles in the adult human brain are not clear. In this study, structural MRIs of 48 patients with GH-secreting pituitary adenoma (GH-PA), 48 sex- and age-matched clinical Non-Functional pituitary adenoma patients (NonFun-PA) and healthy controls (HCs) were assessed using voxel-based morphometry (VBM) and region-based morphometry (RBM). Correlation analyses helped determine the relationships between serum hormone levels and brain structure. The whole-brain gray matter volume (GMV) and white matter volume (WMV) significantly increased at the expense of cerebrospinal fluid volume (CSFV) in GH-PA (Bonferroni corrected, p<0.01). The increase in GMV and reduction in CSFV were significantly correlated with serum GH/IGF-1 levels (p<0.05). VBM showed significant correlations of the GMV/WMV alteration pattern between GH-PA vs HCs and GH-PA vs NonFun-PA and widespread bilateral clusters of significantly increased GMV and WMV in GH-PA (pFDR<0.05). RBM showed obviously increased GMV/WMV in 54 of 68 brain regions (p<0.05) in GH-PA compared to HCs. Our results provide imaging evidence that serum GH/IGF-1 contributes to brain growth, which may be a potential treatment option for neurodegenerative disorders and brain injury in humans.
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http://dx.doi.org/10.18632/aging.102688DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7053622PMC
January 2020

A high-resolution MRI brain template for adult Beagle.

Magn Reson Imaging 2020 05 13;68:148-157. Epub 2020 Jan 13.

State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China.

Canines, which exhibit similar emotional and social processing to humans, are becoming one of the preferred animal models for neuroscience research. Beagles are the most common laboratory canine, thanks to their moderate size, docile nature, and strong immunity. However, there is currently no MRI brain template for the purebred Beagle, which hinders their use in studies involving neuroimaging. Here, we present the Beagle Brain Template (BBT), which consists of high-resolution in vivo T1-weighted and T2-weighted templates, as well as a myelin template, generated from purebred Beagles. We also present a normalized pipeline for mapping individual structure images onto the BBT space. The BBT shows low variation in the tissue probability map and provides descriptive statistics with smaller variability of brain tissue volumes and brain sizes than that of existing templates. This high-resolution purebred canine brain template lays the foundation for future studies aimed at in vivo analyses of the brain structure and function of the Beagle dogs.
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http://dx.doi.org/10.1016/j.mri.2020.01.003DOI Listing
May 2020

Brain structural and functional changes in patients with major depressive disorder: a literature review.

PeerJ 2019 29;7:e8170. Epub 2019 Nov 29.

State Key Laboratory of Brain and Cognitive Science, Beijing MRI Center for Brain Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.

Depression is a mental disorder characterized by low mood and anhedonia that involves abnormalities in multiple brain regions and networks. Epidemiological studies demonstrated that depression has become one of the most important diseases affecting human health and longevity. The pathogenesis of the disease has not been fully elucidated. The clinical effect of treatment is not satisfactory in many cases. Neuroimaging studies have provided rich and valuable evidence that psychological symptoms and behavioral deficits in patients with depression are closely related to structural and functional abnormalities in specific areas of the brain. There were morphological differences in several brain regions, including the frontal lobe, temporal lobe, and limbic system, in people with depression compared to healthy people. In addition, people with depression also had abnormal functional connectivity to the default mode network, the central executive network, and the salience network. These findings provide an opportunity to re-understand the biological mechanisms of depression. In the future, magnetic resonance imaging (MRI) may serve as an important auxiliary tool for psychiatrists in the process of early and accurate diagnosis of depression and finding the appropriate treatment target for each patient to optimize clinical response.
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http://dx.doi.org/10.7717/peerj.8170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6886485PMC
November 2019

Brain Morphometric and Functional Magnetic Resonance Imaging Study on Patients with Visual Field Defects Resulting from Suprasellar Tumors: Preoperative and Postoperative Assessment.

World Neurosurg 2020 Feb 18;134:e353-e359. Epub 2019 Oct 18.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China; Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Beijing Institute for Brain Disorders Brain Tumor Center, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing, China. Electronic address:

Objective: The aim of this study was to investigate the structural and functional changes in the visual cortex in patients with suprasellar tumor with recovery of visual field defects at different times before and after surgical decompression of the optic nerves.

Methods: Twenty-one patients with suprasellar tumor with visual field defects were scanned with structural images and resting-state functional magnetic resonance imaging at 1 week preoperation, 1 week postoperation, and 1 month postoperation. Paired-sample t test was performed on the gray matter volume (GMV) within the occipital cortex, and the significance level was set at false discovery rate (FDR)-adjusted P < 0.05 voxel level to define the region of interest (ROI). One-way analysis of variance was performed on GMV and amplitude of low frequency fluctuation (ALFF) within the ROI. Pearson coefficients were calculated between changes of GMV and ALFF within the ROI and clinical factors.

Results: The GMV in the bilateral pericalcarine cortex increased significantly at 1 month postoperation compared with the preoperative period (FDR-adjusted P < 0.05), with correlation to visual field defects. ALFF values in the bilateral pericalcarine cortex at 1 month postoperation were significantly higher than preoperative values.

Conclusions: The postoperative visual improvement can be reflected in the increased GMV and ALFF of the bilateral pericalcarine cortex at 1 month postoperation, which suggests that an experience-dependent plasticity of the visual cortex was induced by an increase in sensory input.
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http://dx.doi.org/10.1016/j.wneu.2019.10.060DOI Listing
February 2020

Increased resting-state functional connectivity in suprasellar tumor patients with postoperative visual improvement.

Int J Med Sci 2019 14;16(9):1245-1253. Epub 2019 Aug 14.

Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.

Large suprasellar tumors often compress the optic chiasm and give rise to visual impairment. Most patients have significantly improved visual function at 1 to 4 months after chiasmal decompression surgery, and only a few individuals regain normal vision at 1 week after surgery. How the recovery of visual function in these patients affects the visual cortex is not fully understood. In this study, we aimed to investigate alterations in brain functional connectivity (FC) in suprasellar tumor patients with visual improvement using resting-state functional magnetic resonance imaging (rs-fMRI). This longitudinal study was conducted on 13 suprasellar tumor patients who had ophthalmological examinations and rs-fMRI at the following time points: within 1-week preoperation (Pre-op), 1-week postoperation (Post-1w) and 1-month postoperation (Post-1m). The visual impairment score (VIS), local functional correlation (LCOR) and FC values were subjected to one-way ANOVA. Pearson correlation coefficients between changes in the LCOR and clinical factors were calculated. The VIS was significantly decreased at both Post-1w and Post-1m compared to that at Pre-op. Whole-brain analysis of LCOR values showed that the left V1 (primary occipital cortex) was increased significantly at Post-1m compared to that at Pre-op (p < 0.05, FDR corrected). ROI analysis exhibited a significant negative correlation between the LCOR and VIS changes at Post-1m compared to those at Pre-op (p < 0.05, r = - 0.60). FC analysis within the visual network showed that the FC strengths were significantly increased between the left V5 and the left V4, right V3a, left V3, left V2d, and right V5 at Post-1m compared to those at Pre-op (p < 0.05, FDR corrected). Additionally, the FC strengths were significantly increased between the left V5 and the left V1, right orbital-frontal gyrus and left posterior supramarginal gyrus at the whole-brain network level at Post-1m compared to those at Pre-op (p < 0.05, FDR corrected). Postoperative visual improvement can be reflected by the increased FC of the visual cortex at Post-1w and Post-1m, especially at Post-1m. The LCOR value of the left V1 was associated with improved visual outcomes and may be used to objectively assess early visual recovery after chiasmal decompression at Post-1m.
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http://dx.doi.org/10.7150/ijms.35660DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6775267PMC
April 2020

Study of the hippocampal internal architecture in temporal lobe epilepsy using 7 T and 3 T MRI.

Seizure 2019 Oct 9;71:116-123. Epub 2019 Jul 9.

Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Beijing, 100730, China. Electronic address:

Purpose: To compare the hippocampal internal architecture (HIA) between 3 and 7 Tesla (T) magnetic resonance imaging (MRI) in patients with temporal lobe epilepsy (TLE), and to investigate the relationship between HIA and hippocampal volume, and postoperative outcomes.

Materials And Methods: Thirty-nine TLE patients were recruited with 3 and 7 T MRI scans and a semi-quantitative assessment of the HIA was performed. Differences in HIA scores between 3 and 7 T MRI were evaluated. HIA and hippocampal volume asymmetry were also calculated and compared. The utility of HIA and hippocampal volume asymmetry in epilepsy lateralization, and the predictive value between these two indicators were compared. The relationship between HIA and postoperative outcomes was investigated in 25 patients with amygdalohippocampectomy.

Results: HIA scores of epileptogenic hippocampi were lower than those of non-epileptogenic hippocampi at 3 and 7 T MRI. Higher HIA scores were observed at 7 T MRI. The HIA asymmetry and hippocampal volume asymmetry were both strong predictors for epilepsy lateralization and did not show difference in predictive value. No statistical differences in HIA asymmetry were observed between seizure-free patients (ILAE 1) compared to patients with seizures (ILAE 2-5).

Conclusions: Visualization of hippocampal internal architecture (HIA) may be improved at 7 T MRI. HIA asymmetry is a significant predictor of laterality of seizure onset in TLE patients and has similar predictive value as hippocampal volume asymmetry, however, HIA asymmetry at 7 T does not have extra value in determining epilepsy lateralization and neither does predict surgical outcomes.
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http://dx.doi.org/10.1016/j.seizure.2019.06.023DOI Listing
October 2019

ASL perfusion features and type of circle of Willis as imaging markers for cerebral hyperperfusion after carotid revascularization: a preliminary study.

Eur Radiol 2019 May 15;29(5):2651-2658. Epub 2018 Nov 15.

Department of Vascular Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Beijing, China.

Objectives: Cerebral hyperperfusion (CH) could be a disastrous outcome causing complication after carotid revascularization if not managed properly and timely. The aim of this study was to investigate the association between preoperative arterial spin labelling (ASL) perfusion features and circle of Willis (CoW) pattern with CH.

Methods: Forty-eight consecutive carotid stenosis patients who underwent carotid endarterectomy (CEA) or carotid artery stenting (CAS) were enrolled. All patients had single post-labelling delay (PLD) ASL, territory-ASL, and 3-dimensional time-of-flight MR angiography (3D TOF MRA) within 2 weeks before surgery and within 3 days after surgery. Spatial coefficient of variation (CoV) of cerebral blood flow (CBF), whole brain, and territory perfusion volume ratio were calculated from ASL and territory-ASL. Postoperative CoW was classified into two groups based on patency of the first segment of the anterior cerebral arteries (A1) and anterior communicating artery (AcomA). ASL perfusion features, type of CoW, and clinical characteristics were analyzed between CH group and non-CH group to identify CH risk factors.

Results: Higher CoV (p = 0.005) of CBF, lower whole brain perfusion volume ratio (p = 0.012), missing any of A1 or AcomA in CoW (p = 0.002 for postoperative MRA and p = 0.004 for preoperative MRA), and large artery stroke history (p = 0.028) were significantly associated with higher risk of CH. Two cases with cerebral hyperperfusion syndrome (CHS) were also discussed, and their perfusion and angiographic features were shown.

Conclusions: Single-PLD ASL and MRA might be useful and non-invasive imaging tools to identify patients with higher risk of CH after carotid revascularization.

Key Points: • Cerebral hyperperfusion is a critical complication after carotid endarterectomy or carotid artery stenting. • ASL and MRA can be used to identify patients at higher risk of cerebral hyperperfusion • Pattern of circle of Willis, ASL perfusion features, and whole brain perfusion volume ratio are potential predicting markers for hyperperfusion after carotid revascularization.
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http://dx.doi.org/10.1007/s00330-018-5816-1DOI Listing
May 2019
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