Abnormal Metabolic Connectivity in Rats at the Acute Stage of Ischemic Stroke / 神经科学通报·英文版

Stroke at the acute stage is a major cause of disability in adults, and is associated with dysfunction of brain networks. However, the mechanisms underlying changes in brain connectivity in stroke are far from fully elucidated. In the present study, we investigated brain metabolism and metabolic connectivity in a rat ischemic stroke model of middle cerebral artery occlusion (MCAO) at the acute stage using F-fluorodeoxyglucose positron emission tomography. Voxel-wise analysis showed decreased metabolism mainly in the ipsilesional hemisphere, and increased metabolism mainly in the contralesional cerebellum. We used further metabolic connectivity analysis to explore the brain metabolic network in MCAO. Compared to sham controls, rats with MCAO showed most significantly reduced nodal and local efficiency in the ipsilesional striatum. In addition, the MCAO group showed decreased metabolic central connection of the ipsilesional striatum with the ipsilesional cerebellum, ipsilesional hippocampus, and bilateral hypothalamus. Taken together, the present study demonstrated abnormal metabolic connectivity in rats at the acute stage of ischemic stroke, which might provide insight into clinical research.

An Automatic Method for Generating an Unbiased Intensity Normalizing Factor in Positron Emission Tomography Image Analysis After Stroke / 神经科学通报·英文版

Positron emission tomography (PET) imaging of functional metabolism has been widely used to investigate functional recovery and to evaluate therapeutic efficacy after stroke. The voxel intensity of a PET image is the most important indicator of cellular activity, but is affected by other factors such as the basal metabolic ratio of each subject. In order to locate dysfunctional regions accurately, intensity normalization by a scale factor is a prerequisite in the data analysis, for which the global mean value is most widely used. However, this is unsuitable for stroke studies. Alternatively, a specified scale factor calculated from a reference region is also used, comprising neither hyper- nor hypo-metabolic voxels. But there is no such recognized reference region for stroke studies. Therefore, we proposed a totally data-driven automatic method for unbiased scale factor generation. This factor was generated iteratively until the residual deviation of two adjacent scale factors was reduced by < 5%. Moreover, both simulated and real stroke data were used for evaluation, and these suggested that our proposed unbiased scale factor has better sensitivity and accuracy for stroke studies.

Aberrant Effective Connectivity of Subregions of Posterior Cingulate Cortex in Depressive Disorder / 中国医学影像学杂志

Purpose To explore the role of posterior cingulate cortex (PCC) dysfunction in the pathogenesis of depression and its relationship with the clinical features of depression by analyzing the effective connection among the inner areas of PCC of patients in depression.Materials and Methods The spectral dynamic causal model (spDCM) was used to analyze the resting state functional magnetic resonance imaging (fMRI) data from the PCC inner areas Brodmann area (BA) 23,BA29,BA30,BA31 in the major depressive disorder group (MDD,n=23) and healthy control group (HC,n=36).Results Compared with HC group,the strength of BA30 self-connection of MDD group existed significant difference (t=2.53,P＜0.05).In MDD group,the connection of BA23 toward BA31 had abnormal activation,and the abnormal inhibition occurred in BA23 toward BA30;compared with HC group and after a＜0.05 Hz correction,there were significant differences in the bi-directional connections for BA23 and BA31,BA39 and BA31,BA30 and BA31,and in the unidirectional connections for BA23 to BA31,BA30 to BA23,BA30 to BA29 in MDD group.Conelusion The effective connection and connective nodes and edges in the inner areas of PCC in the depression disorder patients were abnormal.

Characteristics of brain functional alterations and task functional magnetic resonance imaging in patients with Cushing's disease / 解放军医学杂志

Objective To analyze the relationship between the brain functional alterations of patients with Cushing's disease (CD) and patients' mental symptom by applying the Evaluating Emotional Scales and task functional magnetic resonance imaging (Task fMRI).Methods Task fMRI was performed on 8 patients with diagnosed CD admitted in the Department of Endocrinology of Chinese PLA General Hospital from Nov. 2015 to Nov. 2016 and 21 healthy people with matched age, gender and education level as control. Meanwhile, Self-Rating Depression Scale (SDS), Self-Rating Anxiety Scale (SAS), Positive and Negative Affective Scale (PANAS) and Cushing Quality of Life Scale (Cushing QOL) were obtained to assess the brain functions.Results Significant depression and anxiety were observed in patients with CD, and their positive affective score was substantially lower while the negative affective score was relatively higher compared with that in the controls. Task fMRI revealed that, when watching the positive pictures, the activation degree of left cerebellum and right postcentral gyrus weakened in CD patients than in the controls, and the positive correlations existed between the activation degree of left cerebellum and the 16 o'clock adrenocorticotrophic hormone (ACTH) level, and between the activation degree of right postcentral gyrus and the urinary free cortisol (UFC) level in CD patients. In contrast, when watching the negative pictures, the activation degree of left cerebellum, bilateral parahippocampal gyrus and left inferior frontal gyrus was weakened in CD patients than in the controls, and the activation degree of left cerebellum was negatively correlated to the 0 o'clock cortisol level and SAS score, but is positively correlated to the UFC level. When watching the neutral pictures, the activation degree of left cerebellum and left parahippocampal gyrus was weakened in CD patients than in the controls.Conclusions CD patients may have impaired brain function with depression and anxiety mental symptoms. By Task fMRI, it can be found that the weakened activation degree of left inferior frontal gyrus, right postcentral gyrus, bilateral parahippocampal gyrus and left cerebellum may be related to CD patients' mental symptoms.

Establishment and Preliminary Clinical Verification for a Software Detecting Estimated Coronary Flow Reserve / 中国循环杂志

Objective: To assess the feasibility of coronary lfow reserve (CFR) detection by SPECT myocardial perfusion imaging using a self developed software with preliminary clinical veriifcation. Methods: CFR calculation software was developed according to Mat lab guide. A total of 16 patients were enrolled including 13 male and 3 female at the mean age of (58±11) years . CAG conifrmed that 25 coronary branches were with stenosis>50% and 23 branches were without stenosis. 2-day ATP/rest99mTc-sestamibi dynamic SPECT myocardial perfusion imaging was conducted to detect CFR. First transit counts were used to sketch the interested pulmonary artery segments and to obtain the arterial input curve of contrast agent as total PAC reached to heart. Reconstructed short-axis images were divided into 3 sections to sketch interested territories (ROI) and to obtain RMC at each territory. Estimated CFR was expressed by the ratio of MBF=RMC/PAC followed by calculating the ratio of MFR=MBFstress/MBFrest. Results: The difference between simulated value and true value could be ignored which conifrmed that our program may accurately measure CFR. The reproducibility by different operators (r=0.986) and the same operator (r=0.983) was good. CFR value in non-stenosis branches were higher than stenosis branches (1.28 ± 0.19) vs (1.10 ± 0.27),P=0.008 and CFR value in stenosis branches was negatively related to stenosis degree (r=-0.5,P=0.02). Conclusion: Our self developed software is reliable for CFR detection by SPECT myocardial perfusion imaging; preliminary study showed good application prospect in clinical practice.

Age-related white matter degradation rule of normal human brain: the evidence from diffusion tensor magnetic resonance imaging / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Diffusion tensor imaging can evaluate white matter function in human brain. Fractional anisotropy is the most important parameter. This study aimed to find regional reduction of fractional anisotropy (FA) with aging in the whole brain and the changing rules of anisotropy with aging.</p><p><b>METHODS</b>Fifty volunteers from 20 to 75 years old were divided into five consecutive age groups; a young group and four senior groups. FA values were calculated with diffusion tensor imaging (DTI) studio software. The difference of FA between the young group and the four senior groups were analyzed by analysis of voxel-level height threshold in Statistic Parametric Mapping (SPM), and the regions with decreased FA were obtained. The FA values of these regions were then extracted using an in-house developed program, and a multiple linear regression model was built to assess the influence of age and sex on the FA values of these regions.</p><p><b>RESULTS</b>Eight regions, including frontal lobe, postcentral gyrus, optic radiation, hippocampus, cerebella hemisphere, corona radiate, corpus callosum and internal capsule, were found to have decreased FA. There was a strong negative correlation between age and the FA in the frontal lobe, postcentral gyrus, optic radiation, hippocampus, and cerebella hemisphere, while a weaker negative correlation in the corona radiate, corpus callosum, and internal capsule was found. The FA reduction in the frontal lobe, postcentral gyrus, optic radiation, hippocampus and cerebella hemisphere were found earlier than in the corona radiate, corpus callosum and internal capsule. There was no correlation between sex and FA in these regions.</p><p><b>CONCLUSIONS</b>The FA in the subcortical white matter area reduces earlier than that in deep white matter. The areas with decreased FA continuously enlarge with aging. The FAs in these regions have a strong negative correlation with age.</p>

Principle and implementation of list-mode image reconstruction in PET / 生物医学工程学杂志

Positron emission tomography (PET) has become basic support equipment in clinical and many other scientific research fields and has been a hot research field at present. Tomography reconstruction algorithm is a key component of PET, and most PETs use statistical iterative reconstruction algorithms from sinograms data currently. However, tomography reconstruction from list-mode data possesses many unique advantages, and it has caused great attention and is in the process of rapid development and improvementin recently. We eventually achieved list-mode tomography reconstruction in this paper, using experimental data of small animal PET scanner Eplus-166, exploiting S-LMEM algorithm and orthogonal distance-based ray-tracer. The results demonstrated that image resolution and contrast recovery achieved inherent properties of the scanner and on-the-fly ray-tracing methods is feasible for dynamic reconstruction.

Volume changes of whole brain gray matter in pediatric patients with Tourette syndrome: evidence from voxel-based morphometry / 中华放射学杂志

ObjectivesTo identify the related abnormalities of gray matter in pediatric patients with Tourette syndrome (TS) by using the optimized voxel-based morphometry (VBM).Methods Three dimensional T1WI was acquired in 31 TS children (28 boys,3 girts,mean age 8 years,range 4-15 years) and 50 age- and sex-matched controls on a 1.5 Tesla Philips scanner. Images were pre-processed and analyzed using a version of VBM 2 in SPM 2.The whole brain gray matter volume was compared between the study and control group by using t-test.Multivariate linear regression analysis was used for analyzing the correlation between the change of grey matter volume within each brain region (mm3 ) and YGTSS score and course of disease of TS patients.Statistical analyses were performed by using SPSS 13.0.ResultsUsing VBM,significant increases in gray matter volumes in left superior parietal lobule, right cerebellar hemisphere and left parahippocampal gyrus were detected in TS patients,and the volume changes were 4059,2126 and 84 mm3 ( t =3.93,3.71,3.58,P ＜ 0.05 ) respectively.Compared to the control group,decreased grey matter volumes were found in medulla and left pons,and the volume changes were 213 and 117 mm3( t =3.53,3.48,P ＜ 0.05 )respectively.Tic severity was not correlated with any volume changes of gray matter in brain (P ＞ 0.05,a small volume correction,KE ≥ 10 voxel).Tic course was negatively correlated with the gray matter volume of left parahippocampal gyrus ( Beta =- 0.391,P =0.039 ).ConclusionsUsing VBM technique,the gray matter abnormalities can be revealed in TS patients without obvious lesions on conventional MR imaging.The increasing volume of temporal and parietal lobes and cerebellar may be an adaptive anatomical change in response to experiential demand. The gray matter volume of the parahippocampal gyrus may be used as one potential objective index for evaluating the prognosis of TS.

MRI for brain structure and function in patients with first-episode panic disorder / 中南大学学报(医学版)

OBJECTIVE@#To determine the brain function and structure in patinets with first-episode panic disorder (PD).@*METHODS@#All subjects (24 PD patients and 24 healthy subjects) received MRI scan and emotional counting Stroop task during the functional magnetic resonance imaging. Blood oxygenation level dependent functional magnetic resonance imaging and voxel-based morphometric technology were used to detect the gray matter volume.@*RESULTS@#Compared with the healthy controls, left thalamus, left medial frontal gyrus, left anterior cingulate gyrus, left inferior frontal gyrus, left insula (panic-related words vs. neutral words) lacked activation in PD patients, but the over-activation were found in right brain stem, right occipital lobe/lingual gyrus in PD patients. Compared with the healthy controls, the gray matter volume in the PD patients significantly decreased in the left superior temporal gyrus, right medial frontal gyrus, left medial occipital gyrus, dorsomedial nucleus of left thalamus and right anterior cingulate gyrus. There was no significantly increased gray matter volume in any brain area in PD patients.@*CONCLUSION@#PD patients have selective attentional bias in processing threatening information due to the depression and weakening of the frontal cingulated gyrus.

Findings in Positron Emission Tomography of Brain in Rats with Syndrome of Stagnation of Liver-Qi / 中国康复理论与实践

@#Objective To explore the characteristics of brain function in rats with Stagnation of Liver-qi Syndrome. Methods Model ofStagnation of Liver-qi was made with chronic stress combined with isolated raising in 10 normal Wistar rats. They were scanned with positronemission tomography (PET) before and after modeling. Data analysis was carried out using SPM (statistical parametric mapping 2) inMATLAB software. Results After modeling, the glucose metabolism decreased (P<0.001) in left frontal lobe, parietal lobe, hypothalamus;bilateral posterior cingulate; right anterior cingulate, while the glucose metabolism increased (P<0.001) in left parahippocampal gyrus, insula,temporal lobe, frontal lobe; right basal ganglia, thalamus. Conclusion The function of some cerebral areas can be changed undergoingStagnation of Liver-qi Syndrome.

Analysis of functional MRI data based on lifting wavelet transform / 中国医学影像技术

Objective To design a fast method based on wavelet analysis for fMRI data. Methods Lifting wavelet decomposition instead of stationary wavelet decomposition was utilized to separate paradigm responsive signal and confound ones in fMRI data, while frequency analysis was used to find out the wavelet scales in which paradigm responsive signal existed, then reconstructed signal from these scales was subjected to correlation analysis for actived pixels. Results Analyzing visual fMRI data revealed that when the significant level was α＜10-6, the proposed method gave more sensitive results than correlation analysis, but process time decreased on a large scale compared with the one based on the stationary wavelet transform. At the mean time, the proposed method only used 24 timepoints of data for wavelet reconstruction while one based on stationary wavelet transform used 256 timepoints of data. Conclusion The proposed method is the fast one based on wavelet transform for analyzing fMRI data, which also gives an effective technique for compressing fMRI data.

Findings in Positron Emission Tomography of Brain in Patients with Syndrome of Stagnation of Liver-Qi / 中国康复理论与实践

@#Objective To explore the characteristics of patients with stagnation of liver-qi syndrome using brain functional imaging techniques.Methods10 patients with stagnation of liver-qi syndrome and 20 normal persons whom paired by sex and age were scanned with positron emission tomography(PET).Data analysis was carried out using SPM in MATLAB software.ResultsCompared with normal,some cerebral areas of the patients with stagnation of liver-qi syndrome showed glucose metabolism letdown(P<0.001),including right parietal lobe(postcentral gyrus,BA1/2),temporal lobe(middle temporal gyrus,BA37),frontal lobe(middle frontal gyrus,BA9/10)etc.,while some cerebral areas showed glucose metabolism heighten(P<0.001)including right frontal lobe(superior frontal gyrus,inferior fontal gyrus,BA22/28/44),right cingulated gyrus,double midbrain and cerebella,etc.ConclusionThe function of some cerebral areas can be changed undergoing stagnation of liver-qi syndrome.

Study of Gray Matter Loss in Alzheimer's Disease Based on Automatic Voxel-based Morphometry / 航天医学与医学工程

Objective To explore the gray matter loss of Alzheimer's disease (AD) patients by processing the magnetic resonance imaging (MRI) with computer. Method A voxel-based morphometry (VBM) method was applied in this study. Result Bilateral loss of gray matter in AD patients was found in the entorhinal/ hippocampal/parahippocampal cortex areas, amygdala, the head of the caudate nucleus, middle temporal gyrus, cingulate gyrus, inferior parietal lobule, insula and dorsolateral prefrontal cortex. Furthermore, area of right pulvinar, cortex of superior temporal gyrus and superior parietal lobule reduced significantly. On the other hand, somatosensory/motor cortex, cerebellum and occipital lobe were relatively intact. Conclusion VBM overcomes the shortcomings of region of interesting(ROI), such as time-consuming, dependence on observer, and poorly reproducible, and can analyze the gray matter loss objectively and automatically and have a good perspective for clinical applications.

Study of brain function imaging induced by acupuncture at acupoint LI4(Hegu) / 中国康复理论与实践

@#ObjectiveTo investigate the time characteristics of brain function induced by acupuncture at acupoint of LI4(Hegu).MethodsThe data of functional magnetic resonance imaging(fMRI) induced by acupuncture at acupoint LI4(Hegu) was processed with modified temporal cluster analysis(MTCA) to obtain the time and trend of brain function.ResultsThe stimulation of acupuncture at acupoint LI4 induced the change of brain function,and time curve of brain functional during the acupuncture experiment was obtained.ConclusionThe effect of acupuncture at acupoint LI4(Hegu) on brain function has time characteristics.

PET imaging of brain function while puncturing the acupoint ST36 / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To explore the experimental method of obtaining position emission tonogiaphy (PET) imaging evidence of changes in cerebral function by puncturing the Stomach 36 (ST36, Zusanli) acupoint.</p><p><b>METHODS</b>Data on changes of cerebral glycometabolism were obtained from six healthy male volunteers with positron emission tomography. Visual experimental evidence, as well as statistical parametric mapping (SPM), was gathered while puncturing the ST36 (Zusanli, right leg) acupoint.</p><p><b>RESULTS</b>There was increased glycometabolism in the hypothalamus, head of the caudate nucleus, temporal lobe, the sinistral cerebellum, postcentral gyrus, and brain stem while the acupoint ST36 was being punctured.</p><p><b>CONCLUSIONS</b>Acupuncture on ST36 can lead to increase in glycometabolism in the vegetative nerve centers, which is correlated with gastric function. Visual experimental evidence of ST36 acupuncturing on functional gastrointestinal disorder was obtained in our study.</p>

Study of Positron Emission Tomography Scanning Image of Alzheimer's disease with SPM Software / 中华老年医学杂志

Objective To study the feature of regional cerebral metabolism rate of glucose (rCMRglc) in patients with Alzheimer’s disease (AD) and the value of positron emission tomography (PET) scanning in diagnosis of AD. Methods 13 AD patients and 13 health controls ,Who matched in age,sex and education years,were scanned with PET. Results (1) Watching by naked eyes,there was mild decreasing of rCMRglc at parietal lobe in healthy elders. While in AD patients,there was widely decreasing of cerebral metabolism rate of glucose. The most significant region was parietal lobe, the next was temporal lobe,and the last was frontal lobe. (2) Detecting with PET and dealing with statistical parametric mapping (SPM) of 99 software,there was more significant decreasing of rCMRglc in regions 7,23,30,31 of cingulate gyrus,region 39 and 40 of pario-occipital lobe,region 20 of temporal lobe and region 6,8,9 of frontal lobe in AD group( P

Central modulating mechanisms of ST36 (Zusanli) acupunctured with PET / 中国康复理论与实践

@#ObjectiveTo discuss the central modulating mechanisms while acupuncturing the Stomach 36[ST36(Zusanli)]by brain functional imaging with positron emission tomography (PET).MethodsPET imaging of whole brain was performed in a group of six healthy subjects during two stimulation paradigms: pseudo acupuncture and real acupuncture at acupoint ST36(Zusanli). The data on cerebral glycometabolism,obtained by using PET,was analyzed by using statistical parametric mapping (SPM).ResultsThere was certain increase of glycometabolism in ipsilateral hypothalamus,back of medulla oblongata;bilateral insular lobe; contralateral paracentral lobule,superior part of precentral and postcentral gyrus,opercular part of frontal and temporal lobe,middle part of cingulate gyrus,head of caudate nucleus,middle part of the back of midbrain and pons,and deep part of cerebellum,whereas decrease in ipsilateral superior part of precentral and postcentral gyrus and lateral part of ipsilateral anterior cerebellar lobe,while acupuncturing at acupoint ST36(Zusanli on the right leg).ConclusionsThe central modulating mechanisms of acupuncturing ST36 are realized by neural and neuroendocrine network modulation mechanisms of vegetative nerve center in cortex and subcortex.