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.

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.
Algorithms ; Humans ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; methods ; Models, Theoretical ; Positron-Emission Tomography ; methods

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.

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.

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.

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.

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.

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

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.

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.