Altered spontaneous brain activity patterns in patients with diabetic retinopathy using amplitude of low-frequency fluctuation

BACKGROUND Diabetes mellitus is a metabolic disorder characterized by prolonged elevation of blood glucose due to various causes.Currently,the relationship between diabetic retinopathy(DR)and altered connectivity of brain function is unclear.AIM To investigate the relationship between this brain activity and clinical manifestations and behaviors of DR patients by using the amplitude of low-frequency fluctuation(ALFF)technique.METHODS Twenty-four DR patients and 24 healthy controls(HCs)matched for age and gender were enrolled.We measured and recorded average ALFF values of DR patients and HCs and then classified them using receiver operating characteristic(ROC)curves.RESULTS ALFF values of both left and right posterior cerebellar lobe and right anterior cingulate gyrus were remarkably higher in the DR patients than in the HCs;however,DR patients had lower values in the bilateral calcarine area.ROC curve analysis of different brain regions demonstrated high accuracy in the area under the curve analysis.There was no significant relationship between mean ALFF values for different regions and clinical presentations in DR patients.Neuronal synchronization abnormalities in some brain regions of DR patients were associated with cognitive and visual disorders.CONCLUSION Abnormal spontaneous brain activity was observed in many areas of DR patients’brains,which may suggest a possible link between clinical manifestations and behaviors in DR patients.

Altered spontaneous brain activity patterns in patients with hyperthyroidism exophthalmos using amplitude of low-frequency fluctuation:a resting-state fMRI study

AIM:To assess changed spontaneous brain activity in hyperthyroid exophthalmos(HE)patients by the amplitude of the low-frequency fluctuation(ALFF)method,and to analyze the correlation between brain activity and ALFF values in these patients.METHODS:Totally 18 HE and 18 hyperthyroid nonexophthalmos(HNE)patients were enrolled.The participants were tested by resting-state functional magnetic resonance imaging,and receiver operating characteristic(ROC)curves were generated to classify the ALFF values of the study population.Pearson’s correlation analysis was utilized to evaluate the relationship between the ALFF values obtained from different brain areas and clinical manifestations.RESULTS:Contrary to HNE patients,we observed lower ALFF values in the left calcarine fissure and surrounding cortex(LCFSC)in HE patients.In the ROC curve analysis of the LCFSC,the area under the curve reflected a high degree of accuracy.In addition,there was positive correlation between mean ALFF values of the LCFSC and the bestcorrected visual acuity of the affected eyes.CONCLUSION:The study displays abnormal brain activity in LCFSC in patients with HE,which might suggest pathological mechanism of visual impairment of HE patients.

Changes in the amplitude of low-frequency fluctuations in specific frequency bands in major depressive disorder after electroconvulsive therapy

BACKGROUND Major depressive disorder(MDD)tends to have a high incidence and high suicide risk.Electroconvulsive therapy(ECT)is currently a relatively effective treatment for MDD.However,the mechanism of efficacy of ECT is still unclear.AIM To investigate the changes in the amplitude of low-frequency fluctuations in specific frequency bands in patients with MDD after ECT.METHODS Twenty-two MDD patients and fifteen healthy controls(HCs)were recruited to this study.MDD patients received 8 ECT sessions with bitemporal placement.Resting-state functional magnetic resonance imaging was adopted to examine regional cerebellar blood flow in both the MDD patients and HCs.The MDD patients were scanned twice(before the first ECT session and after the eighth ECT session)to acquire data.Then,the amplitude of low-frequency fluctuations(ALFF)was computed to characterize the intrinsic neural oscillations in different bands(typical frequency,slow-5,and slow-4 bands).RESULTS Compared to before ECT(pre-ECT),we found that MDD patients after the eighth ECT(post-ECT)session had a higher ALFF in the typical band in the right middle frontal gyrus,posterior cingulate,right supramarginal gyrus,left superior frontal gyrus,and left angular gyrus.There was a lower ALFF in the right superior temporal gyrus.Compared to pre-ECT values,the ALFF in the slow-5 band was significantly increased in the right limbic lobe,cerebellum posterior lobe,right middle orbitofrontal gyrus,and frontal lobe in post-ECT patients,whereas the ALFF in the slow-5 band in the left sublobar region,right angular gyrus,and right frontal lobe was lower.In contrast,significantly higher ALFF in the slow-4 band was observed in the frontal lobe,superior frontal gyrus,parietal lobe,right inferior parietal lobule,and left angular gyrus.CONCLUSION Our results suggest that the abnormal ALFF in pre-and post-ECT MDD patients may be associated with specific frequency bands.

Survivors of COVID-19 exhibit altered amplitudes of low frequency fluctuation in the brain: a resting-state functional magnetic resonance imaging study at 1-year follow-up

Although some short-term follow-up studies have found that individuals recovering from coronavirus disease 2019(COVID-19)exhibit anxiety,depression,and altered brain microstructure,their long-term physical problems,neuropsychiatric sequelae,and changes in brain function remain unknown.This observational cohort study collected 1-year follow-up data from 22 patients who had been hospitalized with COVID-19(8 males and 11 females,aged 54.2±8.7 years).Fatigue and myalgia were persistent symptoms at the 1-year follow-up.The resting state functional magnetic resonance imaging revealed that compared with 29 healthy controls(7 males and 18 females,aged 50.5±11.6 years),COVID-19 survivors had greatly increased amplitude of low-frequency fluctuation(ALFF)values in the left precentral gyrus,middle frontal gyrus,inferior frontal gyrus of operculum,inferior frontal gyrus of triangle,insula,hippocampus,parahippocampal gyrus,fusiform gyrus,postcentral gyrus,inferior parietal angular gyrus,supramarginal gyrus,angular gyrus,thalamus,middle temporal gyrus,inferior temporal gyrus,caudate,and putamen.ALFF values in the left caudate of the COVID-19 survivors were positively correlated with their Athens Insomnia Scale scores,and those in the left precentral gyrus were positively correlated with neutrophil count during hospitalization.The long-term follow-up results suggest that the ALFF in brain regions related to mood and sleep regulation were altered in COVID-19 survivors.This can help us understand the neurobiological mechanisms of COVID-19-related neuropsychiatric sequelae.This study was approved by the Ethics Committee of the Second Xiangya Hospital of Central South University(approval No.2020 S004)on March 19,2020.

AMPLITUDE OF LOW FREQUENCY FLUCTUATION AT DIFFERENT FREQUENCY BANDS IN EARLY AMNESTIC MILD COGNITIVE IMPAIRMENT: RESULTS FROM ADNI

We used resting-state functional magnetic resonance imaging(fMRI)to determine whether there are any abnormalities in different frequency bands between amplitude of low-frequency fluctuations(ALFF)and fractional ALFF(fALFF)and between 10 early amnestic mild cognitive impairment(EMCI)patients and eight normal controls participating in the Alzheimer’s Disease Neuroimaging Initiative(ADNI).We showed widespread difference in ALFF/fALFF between two frequency bands(slow-4:0.027-0.073 Hz,slow-5:0.01-0.027 Hz)in many brain areas including posterior cingulate cortex(PCC),medial prefrontal cortex(MPFC),suprasellar cistern(SC)and ambient cistern(AC).Compared to the normal controls,the EMCI patients showed increased ALFF values in PCu,cerebellum,occipital lobe and cerebellum posterior lobe in frequency band slow-4.While in frequency band slow-5,the EMCI patients showed decreased ALFF values in temporal lobe,left cerebrum and middle temporal gyrus5.Moreover,the EMCI patients showed increased fALFF values in frontal lobe and inferior frontal gyrus in band slow-5.While in frequency band slow-4,the EMCI patients showed decreased fALFF values in limbic lobe,cingulate gyrus and corpus callosum.These results demonstrated that EMCI patients had widespread abnormalities of amplitude of LFF in different frequency bands.

Dynamic alterations of amplitude of low-frequency fluctuations in patients with chronic neck pain

Background:The pathogenesis of neck pain in the brain,which is the fourth most common cause of disability,remains unclear.Furthermore,little is known about the characteristics of dynamic local functional brain activity in cervical pain.Objective:The present study aimed to investigate the changes of local brain activity caused by chronic neck pain and the factors leading to neck pain.Methods:Using the amplitude of low-frequency fluctuations(ALFF)method combined with sliding window approach,we compared local brain activity that was measured by the functional magnetic resonance imaging(fMRI)of 107 patients with chronic neck pain(CNP)with that of 57 healthy control participants.Five pathogenic factors were selected for correlation analysis.Results:The group comparison results of dynamic amplitude of low-frequency fluctuation(dALFF)variability showed that patients with CNP exhibited decreased dALFF variability in the left inferior temporal gyrus,the middle temporal gyrus,the angular gyrus,the inferior parietal marginal angular gyrus,and the middle occipital gyrus.The abnormal dALFF variability of the left inferior temporal gyrus was negatively correlated with the average daily working hours of patients with neck pain.Conclusions:The findings indicated that the brain regions of patients with CNP responsible for audition,vision,memory,and emotion were subjected to temporal variability of abnormal regional brain activity.Moreover,the dALFF variability in the left inferior temporal gyrus might be a risk factor for neck pain.This study revealed the brain dysfunction of patients with CNP from the perspective of dynamic local brain activity,and highlighted the important role of dALFF variability in understanding the neural mechanism of CNP.

Neuropathological characteristics of abnormal white matter functional signaling in adolescents with major depression

BACKGROUND Major depression disorder(MDD)constitutes a significant mental health concern.Epidemiological surveys indicate that the lifetime prevalence of depression in adolescents is much higher than that in adults,with a corresponding increased risk of suicide.In studying brain dysfunction associated with MDD in adolescents,research on brain white matter(WM)is sparse.Some researchers even mistakenly regard the signals generated by the WM as noise points.In fact,studies have shown that WM exhibits similar blood oxygen level-dependent signal fluctuations.The alterations in WM signals and their relationship with disease severity in adolescents with MDD remain unclear.AIM To explore potential abnormalities in WM functional signals in adolescents with MDD.METHODS This study involved 48 adolescent patients with MDD and 31 healthy controls(HC).All participants were assessed using the Patient Health Questionnaire-9 Scale and the mini international neuropsychiatric interview(MINI)suicide inventory.In addition,a Siemens Skyra 3.0T magnetic resonance scanner was used to obtain the subjects'image data.The DPABI software was utilized to calculate the WM signal of the fractional amplitude of low frequency fluctuations(fALFF)and regional homogeneity,followed by a two-sample t-test between the MDD and HC groups.Independent component analysis(ICA)was also used to evaluate the WM functional signal.Pearson’s correlation was performed to assess the relationship between statistical test results and clinical scales.RESULTS Compared to HC,individuals with MDD demonstrated a decrease in the fALFF of WM in the corpus callosum body,left posterior limb of the internal capsule,right superior corona radiata,and bilateral posterior corona radiata[P<0.001,family-wise error(FWE)voxel correction].The regional homogeneity of WM increased in the right posterior limb of internal capsule and left superior corona radiata,and decreased in the left superior longitudinal fasciculus(P<0.001,FWE voxel correction).The ICA results of WM overlapped with those of regional homogeneity.The fALFF of WM signal in the left posterior limb of the internal capsule was negatively correlated with the MINI suicide scale(P=0.026,r=-0.32),and the right posterior corona radiata was also negatively correlated with the MINI suicide scale(P=0.047,r=-0.288).CONCLUSION Adolescents with MDD involves changes in WM functional signals,and these differences in brain regions may increase the risk of suicide.

首发与复发急性期精神分裂症患者静息态低频振幅与分数低频振幅分析

目的:分析首发和复发急性期精神分裂症患者静息态低频振幅与分数低频振幅改变情况。方法:纳入2014年6月至2020年05月在武汉大学人民医院精神卫生中心60例首发、60例复发急性期精神分裂症患者及60名健康对照者进行静息态功能磁共振扫描,采用基于体素水平的低频振幅(ALFF)及分数低频振幅(fALFF)指标分析3组间局部脑功能活动情况。结果:协方差分析显示三组间ALFF值存在显著差异的脑区位于双侧纹状体(左侧F=23.06,P<0.001;右侧F=19.31,P<0.001),而fALFF值存在显著差异的脑区位于双侧纹状体(左侧F=19.71,P<0.001;右侧F=13.53,P<0.001)和前额叶内侧皮质(F=5.46,P<0.001);事后检验显示与对照组相比,首发组和复发组双侧纹状体ALFF及fALFF值均显著升高、内侧前额叶皮质fALFF值降低;复发组内侧前额叶皮质fALFF值降低较首发组更为明显。结论:首发和复发急性期精神分裂症患者均存在双侧纹状体、内侧前额叶皮质的局部功能活动异常,而复发精神分裂症患者内侧前额叶皮质局部脑功能损害更显著。

克罗恩病患者静息态脑功能比率低频振幅及功能连接研究

目的通过比率低频振幅(fALFF)联合基于种子点的功能连接(seed-based FC)在区域和网络水平上探讨静息状态下克罗恩病(CD)患者的脑功能变化情况。方法收集13例经我院诊断为CD的患者以及12名健康志愿者(HC),对被试进行简易智力状态检查量表(MMSE)、汉密顿抑郁量表(HAMD)测试,并采集静息状态脑功能磁共振成像数据。分析fALFF确定种子点,计算种子点与全脑体素之间的功能连接值(zFC)并将差异结果与临床资料、MMSE和HAMD得分进行相关分析。结果与HC组相比,CD组在左侧顶下缘角回、缘上回及角回的zfALFF值减低,左侧辅助运动区、背外侧额上回及右侧辅助运动区、背外侧额上回、中央前回zfALFF值增高;左侧顶下缘角回与右侧枕中回、颞中回的zFC值增高。相关性分析显示,CD组左侧顶下缘角回zfALFF值以及左侧顶下缘角回与右侧枕中回zFC值与病程呈正相关(r=0.555,r=0.623,P<0.05);右侧背外侧额上回zfALFF值与病程、左侧顶下缘角回与右侧枕中回zFC值与洗涤菌群移植(WMT)次数呈负相关(r=-0.614,r=-0.681,P<0.05)。结论CD患者在负责外部环境监测、认知加工以及感觉运动处理的脑区存在功能和调节异常,且WMT对CD患者的脑网络存在影响。

基于ReHo和fALFF的优势半球与非优势半球基底节区脑梗死后运动障碍的静息态脑功能成像研究

目的:采用静息态fMRI技术联合局部一致性(ReHo)和比率低频振幅(fALFF)探讨优势半球与非优势半球基底节区脑梗死后运动障碍患者的脑局部自发活动变化。方法:招募20例基底节区脑梗死后运动障碍患者,按照病灶位置分为优势半球脑梗死组11例和非优势半球脑梗死组9例;招募18例性别、年龄匹配的健康志愿者(对照组)分别行静息态fMRI,利用基于MATLAB的SPM12和DPARSF软件对数据进行分析,采用双样本t检验(体素水平P<0.01,团块水平P<0.05,GRF校正)对3组受试者的ReHo及fALFF脑图行组间两两比较,提取差异脑区的ReHo值及fALFF值。结果:与对照组相比,优势半球脑梗死组左侧三角部额下回的ReHo值显著升高(t=4.97,P<0.05),左侧扣带回白质的fALFF值显著降低(t=-7.57,P<0.05)。与对照组相比,非优势半球脑梗死组左侧额中回的ReHo值显著升高(t=6.01,P<0.05),左侧内侧和旁扣带脑回(t=-6.02,P<0.05)、右侧枕上回(t=-5.25,P<0.05)的ReHo值显著降低,右侧眶部额下回(t=5.01,P<0.05)、左侧枕中回(t=4.74,P<0.05)的fALFF值显著升高,右侧内侧和旁扣带脑回fALFF值显著降低(t=-5.58,P<0.05)。与非优势半球脑梗死组相比,优势半球脑梗死组左侧小脑的ReHo值显著升高(t=4.51,P<0.05),左侧三角部额下回(t=5.29,P<0.05)、左侧舌回(t=5.63,P<0.05)、左侧额中回(t=6.72,P<0.05)的fALFF值显著升高。结论:静息状态下,与对照组相比,优势半球与非优势半球基底节区脑梗死后双侧大脑皮质运动、感觉及认知等多个脑区神经元活动发生变化;与非优势半球脑梗死相比,优势半球脑梗死能更快地出现代偿性激活,增强神经元活动,这一发现可能有助于进一步理解不同半球间基底节区脑梗死后运动障碍患者的大脑局部神经影像学差异。

不同侧小脑梗死患者脑区比率低频振幅的改变及其与认知功能改变的关联

目的:研究不同侧小脑梗死患者不同脑区域的比率低频振幅(fALFF)值的改变及其与认知功能改变的关联性。方法:回顾性研究2022年4月至2024年3月我院神经内科明确诊断的急性单侧小脑梗死的患者92例,以梗死位置分为左侧组45例与右侧组47例,另选取健康体检的受检者50例作为健康对照组,对比不同分组之间的认知功能评分,以及左侧与右侧组患者的fALFF值差异,以及不同脑区域fALFF值与认知功能的相关性。结果:小脑梗死组患者的MMSE评分、RAVLT评分、BNT评分均明显低于健康对照组(P<0.05),TMT耗时相比对照组明显延长(P<0.05)。小脑梗死组患者右侧扣带回、右侧额下回、左侧额上回、小脑后叶的fALFF值差异均相比健康对照组明显升高(P<0.05)。左侧组患者右侧扣带回、额下回、左侧额上回的fALFF值均显著高于右侧组(P<0.05),小脑后叶的fALFF值相比右侧组明显降低(P<0.05)。右侧组右侧额叶的fALFF值与MMSE评分正相关(P<0.05),右侧顶下小叶与MMSE评分负相关(P<0.05),左侧前扣带回与RAVLT评分正相关(P<0.05),左侧顶叶与TMT耗时负相关(P<0.05)。左侧组右侧前额叶、顶下小叶、扣带回与MMSE评分负相关(P<0.05),右侧顶下小叶与RAVLT评分负相关(P<0.05),右侧枕叶与RAVLT评分正相关(P<0.05),右侧顶叶与TMT耗时正相关(P<0.05)。结论:小脑梗死患者相比健康人群的认知功能明显降低,同时梗死对侧关键脑区的fALFF值表现出明显的代偿性升高,与认知功能水平相关性较强。

Local synchronization and amplitude of the fluctuation of spontaneous brain activity in attention-deficit/hyperactivity disorder:a resting-state fMRI study

Regional homogeneity（ReHo）and the amplitude of low-frequency fluctuation（ALFF）are two approaches to depicting different regional characteristics of resting-state functional magnetic resonance imaging（RS-fMRI）data.Whether they can complementarily reveal brain regional functional abnormalities in attention-deficit/hyperactivity disorder（ADHD）remains unknown.In this study,we applied ReHo and ALFF to 23 medication-na ve boys diagnosed with ADHD and 25 age-matched healthy male controls using whole-brain voxel-wise analysis.Correlation analyses were conducted in the ADHD group to investigate the relationship between the regional spontaneous brain activity measured by the two approaches and the clinical symptoms of ADHD.We found that the ReHo method showed widely-distributed differences between the two groups in the fronto-cingulo-occipitocerebellar circuitry,while the ALFF method showed a difference only in the right occipital area.When a larger smoothing kernel and a more lenient threshold were used for ALFF,more overlapped regions were found between ALFF and ReHo,and ALFF even found some new regions with group differences.The ADHD symptom scores were correlated with the ReHo values in the right cerebellum,dorsal anterior cingulate cortex and left lingual gyrus in the ADHD group,while no correlation was detected between ALFF and ADHD symptoms.In conclusion,ReHo may be more sensitive to regional abnormalities,at least in boys with ADHD,than ALFF.And ALFF may be complementary to ReHo in measuring local spontaneous activity.Combination of the two may yield a more comprehensive pathophy-siological framework for ADHD.

Low-frequency fluctuation in continuous real-time feedback of finger force:a new paradigm for sustained attention

Objective Behavioral studies have suggested a low-frequency（0.05 Hz） fluctuation of sustained attention on the basis of the intra-individual variability of reaction-time.Conventional task designs for functional magnetic resonance imaging（fMRI） studies are not appropriate for frequency analysis.The present study aimed to propose a new paradigm,real-time finger force feedback（RT-FFF）,to study the brain mechanisms of sustained attention and neurofeedback.Methods We compared the low-frequency fluctuations in both behavioral and fMRI data from 38 healthy adults（19 males;mean age,22.3 years）.Two fMRI sessions,in RT-FFF and sham finger force feedback（S-FFF） states,were acquired（TR 2 s,Siemens Trio 3-Tesla scanner,8 min each,counter-balanced）.Behavioral data of finger force were obtained simultaneously at a sampling rate of 250 Hz.Results Frequency analysis of the behavioral data showed lower amplitude in the lowfrequency band（0.004-0.104 Hz） but higher amplitude in the high-frequency band（27.02-125 Hz） in the RT-FFF than the S-FFF states.The mean finger force was not significantly different between the two states.fMRI data analysis showed higher fractional amplitude of low-frequency fluctuation（fALFF） in the S-FFF than in the RT-FFF state in the visual cortex,but higher fALFF in RT-FFF than S-FFF in the middle frontal gyrus,the superior frontal gyrus,and the default mode network.Conclusion The behavioral results suggest that the proposed paradigm may provide a new approach to studies of sustained attention.The fMRI results suggest that a distributed network including visual,motor,attentional,and default mode networks may be involved in sustained attention and/or real-time feedback.This paradigm may be helpful for future studies on deficits of attention,such as attention deficit hyperactivity disorder and mild traumatic brain injury.

慢性持续期哮喘儿童脑功能失调的功能磁共振成像研究

目的采用功能磁共振成像(functional magnetic resonance imaging,fMRI)技术研究慢性持续期哮喘儿童脑功能失调的可能机制。方法选取30例慢性持续期哮喘儿童(哮喘组)和30例非哮喘健康儿童(对照组)作为研究对象。收集两组儿童的fMRI检查和注意行为学测试的数据,分析和比较两组儿童的比率低频振幅(fractionalamplitudeoflow-frequencyfluctuation,fALFF)及持续性操作任务(continuousperformancetask,CPT)的反应时间和正确个数。结果哮喘组儿童左侧小脑后叶和左侧枕下小叶的fALFF低于对照组儿童,左侧边缘叶的fALFF高于对照组儿童,差异均有统计学意义(P<0.05)。与对照组儿童比较,哮喘组儿童的CPT反应时间较长,正确个数较少,差异均有统计学意义(P<0.05)。结论哮喘儿童出现注意力缺陷和学习记忆力下降可能与左侧小脑后叶和左侧枕下小叶的功能异常有关,而左侧边缘叶则可能对此有一定的代偿作用。

吸烟成瘾青少年大脑自发活动变化

目的观察吸烟成瘾青少年大脑自发活动变化。方法前瞻性招募吸烟成瘾(吸烟组)与非吸烟成瘾(对照组)在校男大学生各42名,基于静态分数低频振幅(sfALFF)和动态分数低频振幅(dfALFF)方法观察组间大脑局部自发神经活动差异,采用Pearson相关性分析观察吸烟组sfALFF值、dfALFF值与尼古丁依赖测试(FTND)评分、烟龄和吸烟频率的相关性。结果相比对照组,吸烟组左侧距状裂周围皮层、右侧额下回三角部sfALFF值,左侧眶部额中回、左侧颞中回、左侧海马、左侧额下回三角部及右侧楔叶dfALFF值升高,而左侧颞下回、右侧枕中回、右侧顶下缘角回及左侧额中回sfALFF值降低。吸烟组左侧额下回三角部dfALFF值与吸烟频率呈正相关(r=0.286,P=0.033),左侧额中回sfALFF值与FTND评分呈负相关(r=-0.352,P=0.011)。结论吸烟成瘾青少年大脑局部自发神经活动存在异常,并与FTND评分和吸烟频率具有相关性。

未经治疗的帕金森病患者全脑静息态功能磁共振成像的分数低频振幅研究

目的采用静息态功能磁共振成像(fMRI)的分数低频振幅(fALFF)分析方法,探讨未经规范治疗的帕金森病(PD)患者大脑自发性活动强度变化及改变区域的空间分布情况。方法招募2020年4月至2022年6月在该院神经内科就诊的未治疗PD患者33例(PD组),同时招募年龄、性别相匹配的健康志愿者34名作为健康对照组。采集两组全脑静息态fMRI数据。数据预处理后,计算全脑典型频段fALFF,并比较组间差异。为揭示频率相关信息的重要性,分别在Slow-5和Slow-4两个亚频段进行fALFF计算和组间比较。最后,提取PD患者显著改变脑区的fALFF值与Hoehn-Yahr(修订)分级进行相关性分析。结果与健康对照组比较,在典型频段,PD组患者右侧颞上回、右侧中央前回、左侧颞上回、左侧扣带回存在fALFF改变,其中左侧扣带回fALFF值与Hoehn-Yahr(修订)分级呈负相关(r=-0.364,P=0.037)。在亚频段,PD患者组Slow-5频段的多个脑区存在fALFF改变,其中左侧舌回fALFF值与Hoehn-Yahr(修订)分级呈正相关(r=0.376,P=0.031),左侧扣带回fALFF值与Hoehn-Yahr(修订)分级呈负相关(r=-0.359,P=0.040)。结论未经治疗PD患者存在与Hoehn-Yahr(修订)分级相关的自发性脑活动改变。亚频段fALFF值的更多发现为理解PD患者脑功能改变的病理生理机制提供了新的思路。

基于分数低频振幅与功能连接性的湿疹瘙痒症脑影像学特征分析

目的采用静息态功能磁共振成像(resting-state functional magnetic resonance imaging,rs-fMRI)技术,分析瘙痒患者的脑影像学特征。材料与方法选取42名湿疹患者纳入观察组,44名健康受试者纳入对照组。观察组记录瘙痒视觉模拟评分法(VisualAnalogueScale,VAS)评分、12项瘙痒严重程度评估量表(12-ItemPruritusSeverityScale,12-PSS)、湿疹面积及严重程度评分、匹兹堡睡眠质量指数、焦虑自评量表。所有受试者在rs-fMRI扫描后,首先比较分数低频振幅(fraction amplitude of low frequency fluctuation,fALFF)值有差异的脑区,随后以差异脑区为种子点进行全脑功能连接性(functional connectivity,FC)分析。结果两组年龄、性别构成比、受教育年限等基本资料差异无统计学意义(P>0.05)。与对照组相比,观察组左侧中央前回、左侧中央后回、左侧补充运动区、左侧中扣带回的fALFF值增高。观察组左侧中央前回与双侧颞下回、双侧梭状回、双侧海马、双侧颞中回、双侧枕下回、双侧舌回之间的FC值减低;左侧补充运动区与双侧颞下回、双侧颞上回、右侧海马、右侧脑岛的FC值减低。观察组12-PSS评分和左侧中央前回(r=0.59,P<0.01)、左侧中央后回的fALFF值呈正相关(r=0.52,P<0.01),和VAS评分呈正相关(r=0.33,P<0.05)。结论瘙痒患者左侧躯体感觉运动区自发活性异常增高且部分脑区和瘙痒量表之间存在相关性,为今后研究瘙痒提供了潜在的神经生物学标记物;左侧躯体感觉运动区和枕叶、颞叶部分脑区之间的FC同步下降是瘙痒患者另一重要的脑网络特征。

阿尔茨海默病患者静息态下脑局部活动的多指标分析

目的应用静息态功能磁共振(rs-fMRI)低频振幅(ALFF)、比率低频振幅(fALFF)和波动幅度百分比(PerAF)3种指标探究阿尔茨海默病(AD)患者脑部自发性神经活动特点。方法对36例AD患者和40例健康志愿者分别行静息态fMRI扫描,应用ALFF、fALFF和PerAF方法计算并对比两组脑区改变的差异。结果与正常对照组相比较,AD组在双侧尾状核、额内侧回、额上回、直回、前扣带回、嗅皮质,左侧额中回、额下回等区域mALFF值显著增高(P<0.05);在右侧颞中回、颞下回、枕下回、枕中回,双侧距状皮层、楔叶、舌回、枕上回、小脑蚓、楔前叶等区域mALFF值显著减低(P<0.05)。AD组在右侧颞下回、小脑前叶、梭状回,左侧额上回、额内侧回、额中回、额下回、直回、前扣带回等区域mfALFF值显著增高(P<0.05);在双侧舌回,左侧距状皮层、楔叶、枕上回、枕中回、小脑蚓等区域mfALFF值显著减低(P<0.05)。AD组在双侧直回、前扣带回、额内侧回,左侧额上回、尾状核、额中回、额下回、嗅皮质、脑岛等区域mPerAF值显著增高(P<0.05);在双侧距状皮层、楔叶、枕上回、舌回、楔前叶,左侧梭状回、枕下回,右侧顶上小叶、角回、颞中回、颞下回、枕中回等区域mPerAF值显著减低(P<0.05)。结论AD患者默认网络(DMN)和视觉网络存在异常脑活动特征,最显著的神经活动在前额叶皮层和视皮层区域。

高原藏族2型糖尿病患者静息态磁共振成像研究:基于低频振幅和比率低频振幅

目的 旨在探索久居高原环境的藏族2型糖尿病患者(plateau Tibetan type 2 diabetes mellitus, PTDM)与高原藏族健康对照(plateau Tibetan healthy control, PTHC)静息态功能磁共振成像(resting-state functional magnetic resonance imaging, rs-fMRI)局部功能指标的差异及其与认知功能的关系。材料与方法 本研究纳入53名PTDM患者和51名年龄、性别、教育程度匹配良好的PTHC。收集两组患者的人口学资料、临床检验检查结果、神经心理学测试结果和rs-fMRI数据,将rs-fMRI功能指标低频振幅(amplitudeoflow-frequencyfluctuations,ALFF)、比率低频振幅(fractional amplitude of low-frequency fluctuations, fALFF)进行基于体素间的组间差异比较,探究PTDM和PTHC两组间ALFF、fALFF值的差异脑区,及其与人口学、临床检验检查指标和神经心理学测试结果的相关性。结果 与PTHC组相比,PTDM组ALFF值在双侧小脑Ⅷ区降低(P<0.05,FWE校正),fALFF值在右侧舌回、左侧小脑Ⅰ区降低(P<0.05,FWE校正)。相关分析显示,PTDM组患者左侧小脑Ⅷ区(r=0.376,P=0.006)、右侧小脑Ⅷ区(39,-54,-54)(r=0.411,P=0.002)、右侧小脑Ⅷ区(15,-66,-54)(r=0.377,P=0.005)、右侧舌回fALFF值(r=0.337,P=0.014)与年龄呈正相关;PTDM组患者左侧小脑Ⅷ区ALFF值与低密度胆固醇(r=-0.283,P=0.049)、糖化血红蛋白(r=-0.320,P=0.028)、两小时血糖(r=-0.405,P=0.016)呈负相关;右侧舌回fALFF值与Zung氏焦虑自评量表呈负相关(r=-0.399,P=0.012),左侧小脑Ⅰ区fALFF值与吸烟时间呈正相关(r=0.407,P=0.006),与匹兹堡睡眠质量指数量表(r=-0.327,P=0.033)、抑郁自评量表(r=-0.320,P=0.041)及患者健康问卷得分(r=-0.339,P=0.035)呈负相关。结论 高原藏族T2DM患者rs-fMRI局部功能指标在小脑和右侧舌回减低,并与年龄、血糖指标、神经心理及认知功能相关。探究高原藏族T2DM患者的脑功能变化可以更好地了解与疾病相关的认知功能变化及相关机制。

发散式体外冲击波对原发性痛经患者疼痛、情绪及脑功能的即刻影响

目的:探讨发散式体外冲击波(r ESWT)对经期原发性痛经(PDM)患者疼痛、情绪的即刻疗效,并通过静息态功能磁共振(rs-f MRI)观察r ESWT对PDM脑功能的影响。方法:39例PDM患者被随机分为冲击波组(20例)和安慰剂组(19例)。采用简式Mc Gill疼痛问卷(SF-MPQ)、中文版COX痛经症状量表(CMSS)、焦虑自评量表(SAS)和抑郁自评量表(SDS)评估患者的痛经强度、症状、焦虑和抑郁情绪,通过rs-f MRI记录分数低频振幅(f ALFF)。比较患者非经期(月经周期的第12—16天)、经期(月经来潮48h内)治疗前、后的SAS、SDS和f ALFF的差异,经期治疗前、后的SF-MPQ和CMSS的差异。结果:经期治疗后,两组SF-MPQ、CMSS、SAS较经期治疗前均下降(P<0.001),组间无显著差异;两组SDS得分在组内和组间均无显著差异;经期治疗后,冲击波组左侧颞中回的f ALFF较非经期下降(P<0.001)。结论:单次冲击波未即刻改善PDM患者经期的疼痛强度、痛经症状、焦虑、抑郁情绪及静息态脑功能活动。