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Altered spontaneous brain activity patterns in hypertensive retinopathy using fractional amplitude of low-frequency fluctuations:a functional magnetic resonance imaging study
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作者 Xue-Lin Wang Xu-Jun Zheng +8 位作者 Li-Juan Zhang Jin-Yu Hu Hong Wei Qian Ling Liang-Qi He Cheng Chen Yi-Xin Wang Xu Chen Yi Shao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第9期1665-1674,共10页
AIM:To study functional brain abnormalities in patients with hypertensive retinopathy(HR)and to discuss the pathophysiological mechanisms of HR by fractional amplitude of low-frequency fluctuations(fALFFs)method.METHO... AIM:To study functional brain abnormalities in patients with hypertensive retinopathy(HR)and to discuss the pathophysiological mechanisms of HR by fractional amplitude of low-frequency fluctuations(fALFFs)method.METHODS:Twenty HR patients and 20 healthy controls(HCs)were respectively recruited.The age,gender,and educational background characteristics of the two groups were similar.After functional magnetic resonance imaging(fMRI)scanning,the subjects’spontaneous brain activity was evaluated with the fALFF method.Receiver operating characteristic(ROC)curve analysis was used to classify the data.Further,we used Pearson’s correlation analysis to explore the relationship between fALFF values in specific brain regions and clinical behaviors in patients with HR.RESULTS:The brain areas of the HR group with lower fALFF values than HCs were the right orbital part of the middle frontal gyrus(RO-MFG)and right lingual gyrus.In contrast,the values of fALFFs in the left middle temporal gyrus(MTG),left superior temporal pole(STP),left middle frontal gyrus(MFG),left superior marginal gyrus(SMG),left superior parietal lobule(SPL),and right supplementary motor area(SMA)were higher in the HR group.The results of a t-test showed that the average values of fALFFs were statistically significantly different in the HR group and HC group(P<0.001).The fALFF values of the left middle frontal gyrus in HR patients were positively correlated with anxiety scores(r=0.9232;P<0.0001)and depression scores(r=0.9682;P<0.0001).CONCLUSION:fALFF values in multiple brain regions of HR patients are abnormal,suggesting that these brain regions in HR patients may be dysfunctional,which may help to reveal the pathophysiological mechanisms of HR. 展开更多
关键词 hypertensive retinopathy fractional amplitude of low-frequency fluctuation brain region magnetic resonance imaging
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Is it a normal phenomenon for pediatric patients to have brain leptomeningeal contrast enhancement on 3-tesla magnetic resonance imaging?
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作者 Min Ai Hang-Hang Zhang +1 位作者 Yi Guo Jun-Bang Feng 《World Journal of Radiology》 2024年第5期136-138,共3页
Determining whether sevoflurane sedation in children leads to“pseudo”prominent leptomeningeal contrast enhancement(pLMCE)on 3 Tesla magnetic resonance imaging will help reduce overdiagnosis by radiologists and clari... Determining whether sevoflurane sedation in children leads to“pseudo”prominent leptomeningeal contrast enhancement(pLMCE)on 3 Tesla magnetic resonance imaging will help reduce overdiagnosis by radiologists and clarify the pathophysiological changes of pLMCE. 展开更多
关键词 Pediatrics patients SEVOFLURANE brain Prominent leptomeningeal contrast enhancement magnetic resonance imaging
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Structural and functional alterations in the brains of patients with anisometropic and strabismic amblyopia:a systematic review of magnetic resonance imaging studies 被引量:2
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作者 Yuxia Wang Ye Wu +1 位作者 Lekai Luo Fei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2348-2356,共9页
Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanism... Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different.Therefore,we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia;this study is registered with PROSPERO(registration ID:CRD42022349191).We searched three online databases(PubMed,EMBASE,and Web of Science) from inception to April 1,2022;39 studies with 633 patients(324patients with anisometropic amblyo pia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria(e.g.,case-control designed,pee r-reviewed articles) and were included in this review.These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate co rtices during tas k-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations,respectively;these may have arisen from abnormal visual experiences.Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state,as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometro pic amblyopia and strabismic amblyopia patients.The shared dysfunction of anisometro pic amblyopia and strabismic amblyopia patients,relative to controls,is also chara cterized by reduced spontaneous brain activity in the oculomotor co rtex,mainly involving the frontal and parietal eye fields and the cerebellu m;this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia.With regards to specific alterations of the two forms of amblyo pia,anisometropic amblyo pia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients,as reflected by diffusion tensor imaging,and more significant dysfunction and structural loss in the ventral pathway.Strabismic amblyopia patients experience more attenuation of activation in the extrastriate co rtex than in the striate cortex when compared to anisometropic amblyopia patients.Finally,brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients,and the patterns of brain alterations are more limited in amblyopic adults than in childre n.In conclusion,magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alte rations in anisometropic amblyo pia and strabismic amblyopia patients;these alterations may improve our understanding of the neural mechanisms underlying amblyopia. 展开更多
关键词 AMBLYOPIA ANISOMETROPIA brain function magnetic resonance imaging oculomotor system precortical pathway STRABISMUS structure visual cortex
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Review of deep learning and artificial intelligence models in fetal brain magnetic resonance imaging 被引量:1
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作者 Farzan Vahedifard Jubril O Adepoju +5 位作者 Mark Supanich Hua Asher Ai Xuchu Liu Mehmet Kocak Kranthi K Marathu Sharon E Byrd 《World Journal of Clinical Cases》 SCIE 2023年第16期3725-3735,共11页
Central nervous system abnormalities in fetuses are fairly common,happening in 0.1%to 0.2%of live births and in 3%to 6%of stillbirths.So initial detection and categorization of fetal Brain abnormalities are critical.M... Central nervous system abnormalities in fetuses are fairly common,happening in 0.1%to 0.2%of live births and in 3%to 6%of stillbirths.So initial detection and categorization of fetal Brain abnormalities are critical.Manually detecting and segmenting fetal brain magnetic resonance imaging(MRI)could be timeconsuming,and susceptible to interpreter experience.Artificial intelligence(AI)algorithms and machine learning approaches have a high potential for assisting in the early detection of these problems,improving the diagnosis process and follow-up procedures.The use of AI and machine learning techniques in fetal brain MRI was the subject of this narrative review paper.Using AI,anatomic fetal brain MRI processing has investigated models to predict specific landmarks and segmentation automatically.All gestation age weeks(17-38 wk)and different AI models(mainly Convolutional Neural Network and U-Net)have been used.Some models'accuracy achieved 95%and more.AI could help preprocess and postprocess fetal images and reconstruct images.Also,AI can be used for gestational age prediction(with one-week accuracy),fetal brain extraction,fetal brain segmentation,and placenta detection.Some fetal brain linear measurements,such as Cerebral and Bone Biparietal Diameter,have been suggested.Classification of brain pathology was studied using diagonal quadratic discriminates analysis,Knearest neighbor,random forest,naive Bayes,and radial basis function neural network classifiers.Deep learning methods will become more powerful as more large-scale,labeled datasets become available.Having shared fetal brain MRI datasets is crucial because there aren not many fetal brain pictures available.Also,physicians should be aware of AI's function in fetal brain MRI,particularly neuroradiologists,general radiologists,and perinatologists. 展开更多
关键词 Artificial intelligence Fetal brain magnetic resonance imaging NEUROimaging
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Does sevoflurane sedation in pediatric patients lead to“pseudo”leptomeningeal enhancement in the brain on 3 Tesla magnetic resonance imaging? 被引量:1
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作者 Kiran Hilal Kumail Khandwala +2 位作者 Saima Rashid Faheemullah Khan Shayan Sirat Maheen Anwar 《World Journal of Radiology》 2023年第4期127-135,共9页
BACKGROUND Prominent leptomeningeal contrast enhancement(LMCE)in the brain is observed in some pediatric patients during sedation for imaging.However,based on clinical history and cerebrospinal fluid analysis,the pati... BACKGROUND Prominent leptomeningeal contrast enhancement(LMCE)in the brain is observed in some pediatric patients during sedation for imaging.However,based on clinical history and cerebrospinal fluid analysis,the patients are not acutely ill and do not exhibit meningeal signs.Our study determined whether sevoflurane inhalation in pediatric patients led to this pattern of‘pseudo’LMCE(pLMCE)on 3 Tesla magnetic resonance imaging(MRI).AIM To highlight the significance of pLMCE in pediatric patients undergoing enhanced brain MRI under sedation to avoid misinterpretation in reports.METHODS A retrospective cross-sectional evaluation of pediatric patients between 0-8 years of age was conducted.The patients underwent enhanced brain MRI under inhaled sevoflurane.The LMCE grade was determined by two radiologists,and interobserver variability of the grade was calculated using Cohen’s kappa.The LMCE grade was correlated with duration of sedation,age and weight using the Spearman rho rank correlation.RESULTS A total of 63 patients were included.Fourteen(22.2%)cases showed mild LMCE,48(76.1%)cases showed moderate LMCE,and 1 case(1.6%)showed severe LMCE.We found substantial agreement between the two radiologists in detection of pLMCE on post-contrast T1 imaging(kappa value=0.61;P<0.001).Additionally,we found statistically significant inverse and moderate correlations between patient weight and age.There was no correlation between duration of sedation and pLMCE.CONCLUSION pLMCE is relatively common on post-contrast spin echo T1-weighted MRI of pediatric patients sedated by sevoflurane due to their fragile and immature vasculature.It should not be misinterpreted for meningeal pathology.Knowing pertinent clinical history of the child is an essential prerequisite to avoid radiological overcalling and the subsequent burden of additional investigations. 展开更多
关键词 brain Pediatrics Gadolinium contrast Pseudo leptomeningeal enhancement 3 Tesla magnetic resonance imaging SEVOFLURANE
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Epileptic brain network mechanisms and neuroimaging techniques for the brain network
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作者 Yi Guo Zhonghua Lin +1 位作者 Zhen Fan Xin Tian 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2637-2648,共12页
Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal d... Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal discharges.Gaining more detailed information on brain network alterations can help us to further understand the mechanisms of epilepsy and pave the way for brain network-based precise therapeutic approaches in clinical practice.An increasing number of advanced neuroimaging techniques and electrophysiological techniques such as diffusion tensor imaging-based fiber tra ctography,diffusion kurtosis imaging-based fiber tractography,fiber ball imagingbased tra ctography,electroencephalography,functional magnetic resonance imaging,magnetoencephalography,positron emission tomography,molecular imaging,and functional ultrasound imaging have been extensively used to delineate epileptic networks.In this review,we summarize the relevant neuroimaging and neuroelectrophysiological techniques for assessing structural and functional brain networks in patients with epilepsy,and extensively analyze the imaging mechanisms,advantages,limitations,and clinical application ranges of each technique.A greater focus on emerging advanced technologies,new data analysis software,a combination of multiple techniques,and the construction of personalized virtual epilepsy models can provide a theoretical basis to better understand the brain network mechanisms of epilepsy and make surgical decisions. 展开更多
关键词 electrophysiological techniques EPILEPSY functional brain network functional magnetic resonance imaging functional near-infrared spectroscopy machine leaning molecular imaging neuroimaging techniques structural brain network virtual epileptic models
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Contrast Normalization Strategies in Brain Tumor Imaging:From Preprocessing to Classification
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作者 Samar M.Alqhtani Toufique A.Soomro +3 位作者 Faisal Bin Ubaid Ahmed Ali Muhammad Irfan Abdullah A.Asiri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1539-1562,共24页
Cancer-related to the nervous system and brain tumors is a leading cause of mortality in various countries.Magnetic resonance imaging(MRI)and computed tomography(CT)are utilized to capture brain images.MRI plays a cru... Cancer-related to the nervous system and brain tumors is a leading cause of mortality in various countries.Magnetic resonance imaging(MRI)and computed tomography(CT)are utilized to capture brain images.MRI plays a crucial role in the diagnosis of brain tumors and the examination of other brain disorders.Typically,manual assessment of MRI images by radiologists or experts is performed to identify brain tumors and abnormalities in the early stages for timely intervention.However,early diagnosis of brain tumors is intricate,necessitating the use of computerized methods.This research introduces an innovative approach for the automated segmentation of brain tumors and a framework for classifying different regions of brain tumors.The proposed methods consist of a pipeline with several stages:preprocessing of brain images with noise removal based on Wiener Filtering,enhancing the brain using Principal Component Analysis(PCA)to obtain well-enhanced images,and then segmenting the region of interest using the Fuzzy C-Means(FCM)clustering technique in the third step.The final step involves classification using the Support Vector Machine(SVM)classifier.The classifier is applied to various types of brain tumors,such as meningioma and pituitary tumors,utilizing the Contrast-Enhanced Magnetic Resonance Imaging(CE-MRI)database.The proposed method demonstrates significantly improved contrast and validates the effectiveness of the classification framework,achieving an average sensitivity of 0.974,specificity of 0.976,accuracy of 0.979,and a Dice Score(DSC)of 0.957.Additionally,this method exhibits a shorter processing time of 0.44 s compared to existing approaches.The performance of this method emphasizes its significance when compared to state-of-the-art methods in terms of sensitivity,specificity,accuracy,and DSC.To enhance the method further in the future,it is feasible to standardize the approach by incorporating a set of classifiers to increase the robustness of the brain classification method. 展开更多
关键词 brain tumor magnetic resonance imaging principal component analysis fuzzy c-clustering support vector machine
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Acupuncture at Waiguan(SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study 被引量:22
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作者 Ji Qi Junqi Chen +5 位作者 Yong Huang Xinsheng Lai Chunzhi Tang Junjun Yang Hua Chen Shanshan Qu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第3期293-300,共8页
Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effect... Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke were randomly assigned to true point group (true acupuncture at right Waiguan (SJ5)) and sham point group (sham acupuncture). Results of functional magnetic resonance imaging revealed activation in right parietal lobe (Brodmann areas 7 and 19), the right temporal lobe (Brodmann area 39), the right limbic lobe (Brodmann area 23) and bilateral oc-cipital lobes (Brodmann area 18). Furthermore, inhibition of bilateral frontal lobes (Brodmann area 4, 6, and 45), right parietal lobe (Brodmann areas 1 and 5) and left temporal lobe (Brodmann area 21 ) were observed in the true point group. Activation in the precuneus of right parietal lobe (Brodmann area 7) and inhibition of the left superior frontal gyrus (Brodmann area 10) was observed in the sham group. Compared with sham acupuncture, acupuncture at Waiguan in stroke patients inhibited Brodmann area 5 on the healthy side. Results indicated that the altered specificity of sensation-associated cortex (Brodmann area 5) is possibly associated with a central mechanism of acupuncture at Waiguan for stroke patients. 展开更多
关键词 nerve regeneration ACUPUNCTURE Waiguan (SJS) brain injury ischemic stroke function-al magnetic resonance imaging Brodmann area sham point 973 Program neural regeneration
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Quantitative magnetic resonance imaging of the fetal brain in utero: Methods and applications 被引量:3
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作者 Anat Biegon Chen Hoffmann 《World Journal of Radiology》 CAS 2014年第8期523-529,共7页
Application of modern magnetic resonance imaging(MRI) techniques to the live fetus in utero is a relatively recent endeavor. The relative advantages and disadvantages of clinical MRI relative to the widely used and ac... Application of modern magnetic resonance imaging(MRI) techniques to the live fetus in utero is a relatively recent endeavor. The relative advantages and disadvantages of clinical MRI relative to the widely used and accepted ultrasonographic approach are the subject of a continuing debate; however the focus of this review is on the even younger field of quantitative MRI as applied to non-invasive studies of fetal brain development. The techniques covered under this header include structural MRI when followed by quan-titative(e.g., volumetric) analysis, as well as quantita-tive analyses of diffusion weighted imaging, diffusion tensor imaging, magnetic resonance spectroscopy and functional MRI. The majority of the published work re-viewed here reflects information gathered from normal fetuses scanned during the 3rd trimester, with relatively smaller number of studies of pathological samples including common congenital pathologies such as ven-triculomegaly and viral infection. 展开更多
关键词 FETAL brain FETAL magnetic resonance imaging FETAL magnetic resonance spectroscopy FETAL APPARENT diffusion coefficients FETAL functional magnetic resonance imaging CORTICAL development
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Abnormal brain activity in adolescents with Internet addiction who attempt suicide: an assessment using functional magnetic resonance imaging 被引量:3
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作者 Yan Huang Lu Xu +3 位作者 Li Kuang Wo Wang Jun Cao Mu-Ni Xiao 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1554-1559,共6页
Internet addiction is associated with an increased risk of suicidal behavior and can lead to brain dysfunction among adolescents.However,whether brain dysfunction occurs in adolescents with Internet addiction who atte... Internet addiction is associated with an increased risk of suicidal behavior and can lead to brain dysfunction among adolescents.However,whether brain dysfunction occurs in adolescents with Internet addiction who attempt suicide remains unknown.This observational cross-sectional study enrolled 41 young Internet addicts,aged from 15 to 20 years,from the Department of Psychiatry,the First Affiliated Hospital of Chongqing Medical University,China from January to May 2018.The participants included 21 individuals who attempted suicide and 20 individuals with Internet addiction without a suicidal attempt history.Brain images in the resting state were obtained by a 3.0 T magnetic resonance imaging scanner.The results showed that activity in the gyrus frontalis inferior of the right pars triangularis and the right pars opercularis was significantly increased in the suicidal attempt group compared with the non-suicidal attempt group.In the resting state,the prefrontal lobe of adolescents who had attempted suicide because of Internet addiction exhibited functional abnormalities,which may provide a new basis for studying suicide pathogenesis in Internet addicts.The study was authorized by the Ethics Committee of Chongqing Medical University,China(approval No.2017 Scientific Research Ethics(2017-157))on December 11,2017. 展开更多
关键词 adolescents amplitude of low-frequency fluctuation brain activity functional magnetic resonance imaging Internet addiction prefrontal lobe resting state suicidal attempt
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Magnetic resonance imaging in the assessment of brain involvement in alcoholic and nonalcoholic Wernicke's encephalopathy 被引量:4
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作者 Gianvincenzo Sparacia Andrea Anastasi +2 位作者 Claudia Speciale Francesco Agnello Aurelia Banco 《World Journal of Radiology》 CAS 2017年第2期72-78,共7页
AIMTo present the typical and atypical magnetic resonance (MR) imaging findings of alcoholic and non-alcoholic Wernicke’s encephalopathy.METHODSThis study included 7 patients with Wernicke’s encephalopathy (2 men, 5... AIMTo present the typical and atypical magnetic resonance (MR) imaging findings of alcoholic and non-alcoholic Wernicke’s encephalopathy.METHODSThis study included 7 patients with Wernicke’s encephalopathy (2 men, 5 women; mean age, 52.3 years) that underwent brain MR examination between January 2012 and March 2016 in a single institution. Three patients were alcoholics and 4 patients were non-alcoholics. MR protocol included a T2-weighted sequence, a fluid attenuation inversion recovery (FLAIR) sequence, a diffusion-weighted sequence (b = 0 and 1000 s/mm<sup>2</sup>), and a contrast-enhanced MR sequence. All MR images were retrospectively reviewed at baseline and follow-up by two radiologists.RESULTSAll patients with Wernicke’s encephalopathy had bilateral areas showing high signal intensity on both T2-weighted and FLAIR MR images in the typical sites (i.e., the periaqueductal region and the tectal plate). Signal intensity abnormalities in the atypical sites (i.e., the cerebellum and the cerebellar vermis) were seen in 4 patients, all of which had no history of alcohol abuse. Six patients had areas with restricted diffusion in the typical and atypical sites. Four patients had areas showing contrast-enhancement in the typical and atypical sites. Follow-up MR imaging within 6 mo after therapy (intravenous administration of thiamine) was performed in 4 patients, and demonstrated a complete resolution of all the signal intensities abnormalities previously seen in all patients.CONCLUSIONMR imaging is valuable in the diagnosis of Wernicke’s encephalopathy particularly in patients presenting with atypical clinical symptoms, or with no history of alcohol abuse. 展开更多
关键词 brain magnetic resonance imaging Neurodegenerative disorder Wernicke’s encephalopathy
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Functional magnetic resonance imaging and the brain: A brief review 被引量:4
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作者 Maggie SM Chow Sharon L Wu +2 位作者 Sarah E Webb Katie Gluskin DT Yew 《World Journal of Radiology》 CAS 2017年第1期5-9,共5页
Functional magnetic resonance imaging(fMRI) is em-ployed in many behavior analysis studies, with blood oxygen level dependent-(BOLD-) contrast imaging being the main method used to generate images. The use of BOLD-con... Functional magnetic resonance imaging(fMRI) is em-ployed in many behavior analysis studies, with blood oxygen level dependent-(BOLD-) contrast imaging being the main method used to generate images. The use of BOLD-contrast imaging in f MRI has been refined over the years, for example, the inclusion of a spin echo pulse and increased magnetic strength were shown to produce better recorded images. Taking careful precautions to control variables during measurement, comparisons between different specimen groups can be illustrated by f MRI imaging using both quantitative and qualitative methods. Differences have been observed in comparisons of active and resting, developing and aging, and defective and damaged brains in various studies. However, cognitive studies using f MRI still face a number of challenges in interpretation that can only be overcome by imaging large numbers of samples. Furthermore, f MRI studies of brain cancer, lesions and other brain pathologies of both humans and animals are still to be explored. 展开更多
关键词 Functional magnetic resonance image Blood oxygen level dependent imaging Humans Pig and rodent models AGING Drug effects brain lesions and disease
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Value of serial magnetic resonance imaging in the assessment of brain metastases volume control during stereotactic radiosurgery 被引量:2
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作者 Gianvincenzo Sparacia Francesco Agnello +6 位作者 Aurelia Banco Francesco Bencivinni Andrea Anastasi Giovanna Giordano Adele Taibbi Massimo Galia Tommaso Vincenzo Bartolotta 《World Journal of Radiology》 CAS 2016年第12期916-921,共6页
AIM To evaluate brain metastases volume control capabilities of stereotactic radiosurgery(SRS) through serial magnetic resonance(MR) imaging follow-up. METHODS MR examinations of 54 brain metastases in 31 patients bef... AIM To evaluate brain metastases volume control capabilities of stereotactic radiosurgery(SRS) through serial magnetic resonance(MR) imaging follow-up. METHODS MR examinations of 54 brain metastases in 31 patients before and after SRS were reviewed. Patients were included in this study if they had a pre-treatment MR examination and serial follow-up MR examinations at 6 wk, 9 wk, 12 wk, and 12 mo after SRS. The metastasis volume change was categorized at each follow-up as increased(> 20% of the initial volume), stable(± 20% of the initial volume) or decreased(< 20% of the initial volume). RESULTS A local tumor control with a significant(P < 0.05) volume decrease was observed in 25 metastases at 6-wk follow-up. Not significant volume change was observed in 23 metastases and a significant volume increase was observed in 6 metastases. At 9-wk followup, 15 out of 25 metastases that decreased in size at 6 wk had a transient tumor volume increase, followed by tumor regression at 12 wk. At 12-wk follow-up there was a significant reduction in volume in 45 metastases, and a significant volume increase in 4 metastases. At 12-mo follow-up, 19 metastases increased significantly in size(up to 41% of the initial volume). Volume tumor reduction was correlated to histopathologic subtype.CONCLUSION SRS provided an effective local brain metastases volume control that was demonstrated at follow-up MR imaging. 展开更多
关键词 brain metastases Stereotactic radiosurgery magnetic resonance imaging Pseudo-progression Radiation therapy
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Magnetic resonance imaging-three-dimensional printing technology fabricates customized scaffolds for brain tissue engineering 被引量:1
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作者 Feng Fu Zhe Qin +10 位作者 Chao Xu Xu-yi Chen Rui-xin Li Li-na Wang Ding-wei Peng Hong-tao Sun Yue Tu Chong Chen Sai Zhang Ming-liang Zhao Xiao-hong Li 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第4期614-622,共9页
Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to crea... Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to create customized scaffolds with high precision and accuracy. In this study, an electrically controlled cortical impactor was used to induce randomized brain tissue defects. The overall shape of scaffolds was designed using rat-specific anatomical data obtained from magnetic resonance imaging, and the internal structure was created by computer- aided design. As the result of limitations arising from insufficient resolution of the manufacturing process, we magnified the size of the cavity model prototype five-fold to successfully fabricate customized collagen-chitosan scaffolds using three-dimensional printing. Results demonstrated that scaffolds have three-dimensional porous structures, high porosity, highly specific surface areas, pore connectivity and good internal characteristics. Neural stem cells co-cultured with scaffolds showed good viability, indicating good biocompatibility and biodegradability. This technique may be a promising new strategy for regenerating complex damaged brain tissues, and helps pave the way toward personalized medicine. 展开更多
关键词 nerve regeneration three-dimensional printing traumatic brain injury tissue engineering scaffolds magnetic resonance imaging COLLAGEN CHITOSAN MIMICS neural regeneration
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Activation of brain areas following ankle dorsiflexion versus plantar flexion Functional magnetic resonance imaging verification 被引量:1
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作者 Tianyu Jiang Weiping Wu +3 位作者 Xinglin Wang Changshui Weng Qiuhua Wang Yanmei Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第7期501-505,共5页
Changes in activated areas of the brain during ankle active dorsiflexion and ankle active plantar flexion were observed in six healthy subjects using functional magnetic resonance imaging. Excited areas of ankle activ... Changes in activated areas of the brain during ankle active dorsiflexion and ankle active plantar flexion were observed in six healthy subjects using functional magnetic resonance imaging. Excited areas of ankle active dorsiflexion involved the bilateral primary motor area and the primary somatosensory area, as well as the bilateral supplementary sensory area, the primary visual area, the right second visual area, and the vermis of cerebellum. Excited areas of ankle active plantar flexion included the ipsilateral supplementary motor area, the limbic system, and the contralateral corpus striatum. Fine movements of the cerebral cortex control the function of the ankle dorsiflexion to a larger extent than ankle plate flexion, and the function of ankle plate flexion is more controlled by the subcortical area. 展开更多
关键词 ankle dorsiflexion ankle plantar flexion functional magnetic resonance imaging brain function activated areas
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Fetal brain tumors:Prenatal diagnosis by ultrasound and magnetic resonance imaging 被引量:7
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作者 Herbene Jose Milani Edward Araujo Junior +6 位作者 Sergio Cavalheiro Patrícia Soares Oliveira Wagner Jou Hisaba Enoch Quindere Sa Barreto Maurício Mendes Barbosa Luciano Marcondes Nardozza Antonio Fernandes Moron 《World Journal of Radiology》 2015年第1期17-21,共5页
Congenital central nervous system tumors diagnosed during pregnancy are rare, and often have a poor prognosis. The most frequent type is the teratoma. Use of ultrasound and magnetic resonance image allows the suspicio... Congenital central nervous system tumors diagnosed during pregnancy are rare, and often have a poor prognosis. The most frequent type is the teratoma. Use of ultrasound and magnetic resonance image allows the suspicion of brain tumors during pregnancy. However, the definitive diagnosis is only confirmed after birth by histology. The purpose of this mini-review article is to describe the general clinical aspects of intracranial tumors and describe the main fetal brain tumors. 展开更多
关键词 FETUS brain tumors TERATOMA ULTRASOUND magnetic resonance imaging
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Altered spontaneous brain activity in patients with diabetic optic neuropathy:A resting-state functional magnetic resonance imaging study using regional homogeneity 被引量:1
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作者 Gui-Ying Guo Li-Juan Zhang +7 位作者 Biao Li Rong-Bin Liang Qian-Min Ge Hui-Ye Shu Qiu-Yu Li Yi-Cong Pan Chong-Gang Pei Yi Shao 《World Journal of Diabetes》 SCIE 2021年第3期278-291,共14页
BACKGROUND Diabetes is a common chronic disease.Given the increasing incidence of diabetes,more individuals are affected by diabetic optic neuropathy(DON),which results in decreased vision.Whether DON leads to abnorma... BACKGROUND Diabetes is a common chronic disease.Given the increasing incidence of diabetes,more individuals are affected by diabetic optic neuropathy(DON),which results in decreased vision.Whether DON leads to abnormalities of other visual systems,including the eye,the visual cortex,and other brain regions,remains unknown.AIM To investigate the local characteristics of spontaneous brain activity using regional homogeneity(ReHo)in patients with DON.METHODS We matched 22 patients with DON with 22 healthy controls(HCs).All subjects underwent resting-state functional magnetic resonance imaging.The ReHo technique was used to record spontaneous changes in brain activity.Receiver operating characteristic(ROC)curves were applied to differentiate between ReHo values for patients with DON and HCs.We also assessed the correlation between Hospital Anxiety and Depression Scale scores and ReHo values in DON patients using Pearson correlation analysis.RESULTS ReHo values of the right middle frontal gyrus(RMFG),left anterior cingulate(LAC),and superior frontal gyrus(SFG)/left frontal superior orbital gyrus(LFSO)were significantly lower in DON patients compared to HCs.Among these,the greatest difference was observed in the RMFG.The result of the ROC curves suggest that ReHo values in altered brain regions may help diagnose DON,and the RMFG and LAC ReHo values are more clinically relevant than SFG/LFSO.We also found that anxiety and depression scores of the DON group were extremely negatively correlated with the LAC ReHo values(r=-0.9336,P<0.0001 and r=-0.8453,P<0.0001,respectively).CONCLUSION Three different brain regions show ReHo changes in DON patients,and these changes could serve as diagnostic and/or prognostic biomarkers to further guide the prevention and treatment of DON patients. 展开更多
关键词 DIABETES Diabetic optic neuropathy Regional homogeneity Resting state Functional magnetic resonance imaging brain activity
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Diffusion tensor imaging and proton magnetic resonance spectroscopy in brain tumor Correlation between structure and metabolism
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作者 Zhigang Min Chen Niu +2 位作者 Netra Rana Huanmei Ji Ming Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第10期930-937,共8页
Proton magnetic resonance spectroscopy and diffusion tensor imaging are non-invasive techniques used to detect metabolites and water diffusion in vivo. Previous studies have confirmed a positive correlation of individ... Proton magnetic resonance spectroscopy and diffusion tensor imaging are non-invasive techniques used to detect metabolites and water diffusion in vivo. Previous studies have confirmed a positive correlation of individual fractional anisotropy values with N-acetylaspartate/creatine and N-acetylaspartate/choline ratios in tumors, edema, and normal white matter. This study divided the brain parenchyma into tumor, pedtumoral edema, and normal-appearing white matter according to MRI data, and analyzed the correlation of metabolites with water molecular diffusion. Results demonstrated that in normal-appearing white matter, N-acetylaspartate/creatine ratios were positively correlated with fractional anisotropy values, negatively correlated with radial diffusivities, and positively correlated with maximum eigenvalues. Maximum eigenvalues and radial diffusivities in peritumoral edema showed a negative correlation with choline, N-acetylaspartate, and creatine. Radial diffusivities in tumor demonstrated a negative correlation with choline. These data suggest that the relationship between metabolism and structure is markedly changed from normal white matter to peritumoral edema and tumor. Neural metabolism in the peritumoral edema area decreased with expanding extracellular space. The normal relationship of neural function and microstructure disappeared in the tumor region. 展开更多
关键词 neural regeneration NEUROimaging brain neoplasms magnetic resonance spectroscopy diffusiontensor imaging METABOLISM diffusion anisotropy EDEMA nerve fiber extracellular space correlation analysis grants-supported paper NEUROREGENERATION
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IN VIVO MAPPING BRAIN MICROCIRCULATION BY LASER SPECKLE CONTRAST IMAGING:A MAGNETIC RESONANCE PERSPECTIVE OF THEORETICAL FRAMEWORK
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作者 ZHENG WANG 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2008年第2期239-256,共18页
The fundamental limitations of most vascular-based functional neuroimaging techniques are placed by the fact how fine the brain regulates the blood supply system.In vivo mapping of the cerebral microcirculation with h... The fundamental limitations of most vascular-based functional neuroimaging techniques are placed by the fact how fine the brain regulates the blood supply system.In vivo mapping of the cerebral microcirculation with high resolution and sensitivity hence becomes unprecedentedly compelling.This paper reviews the theoretical background of the laser speckle contrast imaging(LSCI)technique and attempts to present a complete framework stemming from a simple biophysical model.Through the sensitivity analysis,more insights into the tool optimization are attained for in vivo applications.Open questions of the technical aspects are discussed within this unified framework.Finally,it concludes with a brief perspective of future research in a way analogous to the magnetic resonance imaging(MRI)technique.Such exploration could catalyze their development and initiate a technological fusion for precise assessment of blood flow across various spatial scales. 展开更多
关键词 Laser speckle contrast imaging brain microcirculation functional neuroimaging magnetic resonance imaging
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Advanced magnetic resonance imaging techniques in brain tumours surgical planning
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作者 Giada Zoccatelli Franco Alessandrini +1 位作者 Alberto Beltramello Andrea Talacchi 《Journal of Biomedical Science and Engineering》 2013年第3期403-417,共15页
Morphological assessment using Computed Tomo-graphy (CT) or Magnetic Resonance Imaging (MRI) is still the workhorse of tumor detection and diagnosis. In particular, MRI provides detailed information about cerebral tum... Morphological assessment using Computed Tomo-graphy (CT) or Magnetic Resonance Imaging (MRI) is still the workhorse of tumor detection and diagnosis. In particular, MRI provides detailed information about cerebral tumor anatomy, cellular metabolism and hemodynamic features, making it a fundamental tool for a correct diagnosis, treatment and monitoring of the disease. Various new functional imaging modalities assessing tissue microstructure and physiology have increased the scope of neuro imaging and raised expectations among clinicians. This article provides an overview of the most advanced MR imaging techniques (functional MRI, perfusion-weighted imaging, diffusion-weighted imaging and MR spectroscopy) now available for neurosurgical planning and their role in brain tumors assessment. Their pros and cons are analyzed in order to find out which one may be chosen as best diagnostic pre-surgical protocol. At the moment none of the single techniques can be considered the golden standard;only the integration of advanced and conventional MR imaging proves to be a reliable tool in the hands of the neuro-radiologist and neurosurgeon, thus maximazing tumor resection and function preservation. 展开更多
关键词 magnetic resonance imaging brain TUMOR NEUROSURGERY brain MAPPING
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