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Sample records for brain mri study

  1. Longitudinal MRI studies of brain morphometry

    DEFF Research Database (Denmark)

    Skimminge, Arnold Jesper Møller

    into the accompanying deformation field. Deformation fields from high dimensional warping founds tensor based morphometry (TBM), and provides unique opportunities to study human brain morphology and plasticity. In this thesis, specially adapted image processing streams utilizing several image registration techniques......High resolution MR images acquired at multiple time points of the brain allow quantification of localized changes induced by external factors such as maturation, ageing or disease progression/recovery. High-dimensional warping of such MR images incorporates changes induced by external factors...

  2. A study of brain MRI findings in children with epilepsy

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    Kanematsu, Sachiko; Sumida, Sawako; Muto, Ayako; Osawa, Makiko; Ono, Yuko [Tokyo Women' s Medical Coll. (Japan); Uchida, Moriyasu; Maruyama, Hiroshi

    2000-06-01

    Magnetic resonance imaging in the brain was performed in 293 patients with childhood-onset (<15 y.o.) epilepsy who had been classified into 4 groups, idiopathic localization-related epilepsy (ILRE), 78 patients; idiopathic generalized epilepsy (IGE), 116 patients; symptomatic localization-related epilepsy (SLRE), 68 patients and symptomatic generalized epilepsy (SGE), 31 patients, with the Classification of Epilepsies and Epileptic Syndrome (1989 International League Against Epilepsy). The examination was performed with a 1.5 T magnet. One hundred twenty-five patients (42.7%) showed abnormal findings, and the incidence in each group was as follows: Idiopathic epilepsy: The rate of abnormal findings in the ILRE and IGE groups was 21.8% and 20.7%, respectively. Most of the abnormal findings were secondary changes, such as diffuse or localized brain atrophy. Of the congenital abnormalities, the main finding was arachnoid cyst. Symptomatic epilepsy: The rate of abnormality in the SLRE patients was 88.2%, and 85% of the findings were secondary changes, i.e., brain atrophy, or degeneration of the white matter. In the SGE group, the rate was 77.4%, with an almost equal percentage of congenital and secondary changes. Of 255 patients who were examined by electroencephalography (EEG) on the same day as MRI, about 50% showed a correlation between the EEG records and the MRI abnormalities. However, only 8 patients showed a correlation in localization between the EEG and MRI abnormalities. (author)

  3. Building an EEG-fMRI multi-modal brain graph: a concurrent EEG-fMRI study

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    Qingbao Yu

    2016-09-01

    Full Text Available The topological architecture of brain connectivity has been well characterized by graph theory based analysis. However, previous studies have primarily built brain graphs based on a single modality of brain imaging data. Here we develop a framework to construct multi-modal brain graphs using concurrent EEG-fMRI data which are simultaneously collected during eyes open (EO and eyes closed (EC resting states. FMRI data are decomposed into independent components with associated time courses by group independent component analysis (ICA. EEG time series are segmented, and then spectral power time courses are computed and averaged within 5 frequency bands (delta; theta; alpha; beta; low gamma. EEG-fMRI brain graphs, with EEG electrodes and fMRI brain components serving as nodes, are built by computing correlations within and between fMRI ICA time courses and EEG spectral power time courses. Dynamic EEG-fMRI graphs are built using a sliding window method, versus static ones treating the entire time course as stationary. In global level, static graph measures and properties of dynamic graph measures are different across frequency bands and are mainly showing higher values in eyes closed than eyes open. Nodal level graph measures of a few brain components are also showing higher values during eyes closed in specific frequency bands. Overall, these findings incorporate fMRI spatial localization and EEG frequency information which could not be obtained by examining only one modality. This work provides a new approach to examine EEG-fMRI associations within a graph theoretic framework with potential application to many topics.

  4. Building an EEG-fMRI Multi-Modal Brain Graph: A Concurrent EEG-fMRI Study

    Science.gov (United States)

    Yu, Qingbao; Wu, Lei; Bridwell, David A.; Erhardt, Erik B.; Du, Yuhui; He, Hao; Chen, Jiayu; Liu, Peng; Sui, Jing; Pearlson, Godfrey; Calhoun, Vince D.

    2016-01-01

    The topological architecture of brain connectivity has been well-characterized by graph theory based analysis. However, previous studies have primarily built brain graphs based on a single modality of brain imaging data. Here we develop a framework to construct multi-modal brain graphs using concurrent EEG-fMRI data which are simultaneously collected during eyes open (EO) and eyes closed (EC) resting states. FMRI data are decomposed into independent components with associated time courses by group independent component analysis (ICA). EEG time series are segmented, and then spectral power time courses are computed and averaged within 5 frequency bands (delta; theta; alpha; beta; low gamma). EEG-fMRI brain graphs, with EEG electrodes and fMRI brain components serving as nodes, are built by computing correlations within and between fMRI ICA time courses and EEG spectral power time courses. Dynamic EEG-fMRI graphs are built using a sliding window method, versus static ones treating the entire time course as stationary. In global level, static graph measures and properties of dynamic graph measures are different across frequency bands and are mainly showing higher values in eyes closed than eyes open. Nodal level graph measures of a few brain components are also showing higher values during eyes closed in specific frequency bands. Overall, these findings incorporate fMRI spatial localization and EEG frequency information which could not be obtained by examining only one modality. This work provides a new approach to examine EEG-fMRI associations within a graph theoretic framework with potential application to many topics. PMID:27733821

  5. Brain Activity Associated with Emoticons: An fMRI Study

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    Yuasa, Masahide; Saito, Keiichi; Mukawa, Naoki

    In this paper, we describe that brain activities associated with emoticons by using fMRI. In communication over a computer network, we use abstract faces such as computer graphics (CG) avatars and emoticons. These faces convey users' emotions and enrich their communications. However, the manner in which these faces influence the mental process is as yet unknown. The human brain may perceive the abstract face in an entirely different manner, depending on its level of reality. We conducted an experiment using fMRI in order to investigate the effects of emoticons. The results show that right inferior frontal gyrus, which associated with nonverbal communication, is activated by emoticons. Since the emoticons were created to reflect the real human facial expressions as accurately as possible, we believed that they would activate the right fusiform gyrus. However, this region was not found to be activated during the experiment. This finding is useful in understanding how abstract faces affect our behaviors and decision-making in communication over a computer network.

  6. MRI brain imaging.

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    Skinner, Sarah

    2013-11-01

    General practitioners (GPs) are expected to be allowed to request MRI scans for adults for selected clinically appropriate indications from November 2013 as part of the expansion of Medicare-funded MRI services announced by the Federal Government in 2011. This article aims to give a brief overview of MRI brain imaging relevant to GPs, which will facilitate explanation of scan findings and management planning with their patients. Basic imaging techniques, common findings and terminology are presented using some illustrative case examples.

  7. EEG-fMRI integration for the study of human brain function.

    Science.gov (United States)

    Jorge, João; van der Zwaag, Wietske; Figueiredo, Patrícia

    2014-11-15

    Electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) have proved to be extremely valuable tools for the non-invasive study of human brain function. Moreover, due to a notable degree of complementarity between the two modalities, the combination of EEG and fMRI data has been actively sought in the last two decades. Although initially focused on epilepsy, EEG-fMRI applications were rapidly extended to the study of healthy brain function, yielding new insights into its underlying mechanisms and pathways. Nevertheless, EEG and fMRI have markedly different spatial and temporal resolutions, and probe neuronal activity through distinct biophysical processes, many aspects of which are still poorly understood. The remarkable conceptual and methodological challenges associated with EEG-fMRI integration have motivated the development of a wide range of analysis approaches over the years, each relying on more or less restrictive assumptions, and aiming to shed further light on the mechanisms of brain function along with those of the EEG-fMRI coupling itself. Here, we present a review of the most relevant EEG-fMRI integration approaches yet proposed for the study of brain function, supported by a general overview of our current understanding of the biophysical mechanisms coupling the signals obtained from the two modalities.

  8. Brain MRI in Parkinson's disease

    NARCIS (Netherlands)

    Meijer, F.J.A.; Goraj, B.M.

    2014-01-01

    In this review article, conventional brain MRI and advanced MRI techniques in Parkinson`s disease (PD) are discussed, with emphasis on clinical relevance. Conventional brain MRI sequences generally demonstrate limited abnormalities specific for PD and in clinical practice brain MRI is mainly used to

  9. Effects of motor fatigue on human brain activity, an fMRI study

    NARCIS (Netherlands)

    van Duinen, Hiske; Renken, Remco; Maurits, Natasha; Zijdewind, Inge

    2007-01-01

    The main purpose of this study was to investigate effects of motor fatigue on brain activation in humans, using fMRI. First, we assessed brain activation that correlated with muscle activity during brief contractions at different force levels (force modulation). Second, a similar analysis was done f

  10. Neurobiological origin of spurious brain morphological changes: A quantitative MRI study.

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    Lorio, Sara; Kherif, Ferath; Ruef, Anne; Melie-Garcia, Lester; Frackowiak, Richard; Ashburner, John; Helms, Gunther; Lutti, Antoine; Draganski, Bodgan

    2016-05-01

    The high gray-white matter contrast and spatial resolution provided by T1-weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1-weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1-weighted images (R1 (=1/T1), R2 *, and PD) in a large cohort of healthy subjects (n = 120, aged 18-87 years). Synthetic T1-weighted images were calculated from these quantitative maps and used to extract morphometry features-gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue-myelination, iron, and water content-on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801-1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc.

  11. A STUDY ON PERITUMORAL BRAIN EDEMA AROUND MENINGIOMAS BY MRI AND CONTRAST CT

    NARCIS (Netherlands)

    GO, KG; KAMMAN, RL; WILMINK, JT; MOOYAART, EL

    1994-01-01

    In the present study upon 9 meningiomas, the volume of peritumoral brain edema was calculated by integration of the cross-sectional edematous areas on serial MRI slices. It was zero in 3 cases and ranged from 11 to 176.4 ml in the other cases. There was disruption of the cortex in all cases, ranging

  12. EEG-fMRI methods for the study of brain networks during sleep

    Directory of Open Access Journals (Sweden)

    Jeff H. Duyn

    2012-07-01

    Full Text Available Modern neuroimaging methods may provide unique insights into the mechanism and role of sleep, as well as into particular mechanisms of brain function in general. Many of the recent neuroimaging studies have used concurrent EEG and fMRI, which present unique technical challenges ranging from the difficulty of inducing sleep in the MRI environment to appropriate instrumentation and data processing methods to obtain artifact free data. In addition, the use of EEG-fMRI during sleep leads to unique data interpretation issues, as common approaches developed for the analysis of task-evoked activity do not apply to sleep. Reviewed are a variety of statistical approaches that can be used to characterize brain activity from fMRI data acquired during sleep, with an emphasis on approaches that investigate the presence of correlated activity between brain regions. Each of these approaches has advantages and disadvantages that must be considered in concert with the theoretical questions of interest. Specifically, fundamental theories of sleep control and function should be considered when designing these studies and when choosing the associated statistical approaches. For example, the notion that local brain activity during sleep may be triggered by local, use-dependent activity during wakefulness may be tested by analyzing sleep networks as statistically independent components. Alternatively, the involvement of regions in more global processes such as arousal may be investigated with correlation analysis.

  13. Studies on the reliability of high-field intra-operative MRI in brain glioma resection

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    Zhi-jun SONG

    2011-07-01

    Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.

  14. Body growth and brain development in premature babies: an MRI study

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    Tzarouchi, Loukia C.; Zikou, Anastasia; Kosta, Paraskevi; Argyropoulou, Maria I. [University of Ioannina, Department of Radiology, Medical School, Ioannina (Greece); Drougia, Aikaterini; Andronikou, Styliani [University of Ioannina, Intensive Care Unit, Child Health Department, Medical School, Ioannina (Greece); Astrakas, Loukas G. [University of Ioannina, Department of Medical Physics, Medical School, Ioannina (Greece)

    2014-03-15

    Prematurity and intrauterine growth restriction are associated with neurodevelopmental disabilities. To assess the relationship between growth status and regional brain volume (rBV) and white matter microstructure in premature babies at around term-equivalent age. Premature infants (n= 27) of gestational age (GA): 29.8 ± 2.1 weeks, with normal brain MRI scans were studied at corrected age: 41.2 ± 1.4 weeks. The infants were divided into three groups: 1) appropriate for GA at birth and at the time of MRI (AGA), 2) small for GA at birth with catch-up growth at the time of MRI (SGA{sub a}) and 3) small for GA at birth with failure of catch-up growth at the time of MRI (SGA{sub b}). The T1-weighted images were segmented into 90 rBVs using the SPM8/IBASPM and differences among groups were assessed. Fractional anisotropy (FA) was measured bilaterally in 15 fiber tracts and its relationship to GA and somatometric measurements was explored. Lower rBV was observed in SGA{sub b} in superior and anterior brain areas. A positive correlation was demonstrated between FA and head circumference and body weight. Body weight was the only significant predictor for FA (P< 0.05). In premature babies, catch-up growth is associated with regional brain volume catch-up at around term-equivalent age, starting from the brain areas maturing first. Body weight seems to be a strong predictor associated with WM microstructure in brain areas related to attention, language, cognition, memory and executing functioning. (orig.)

  15. Clinical studies of cerebral arteriosclerosis in diabetic subjects. Analysis with brain MRI study

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    Ohashi, Makoto; Tanahashi, Hideo (Osaka Rosai Hospital, Sakai (Japan)); Nomura, Makoto; Yamada, Yoshio; Abe, Hiroshi

    1994-11-01

    In order to investigate the clinical characteristics of cerebral arteriosclerosis in diabetic subjects, brain MRI studies were conducted in diabetic patients and healthy subjects. The subjects were 93 diabetic patients without symptoms and signs of cerebral infarction (49 males and 44 females) with a mean age of 59 years and 73 healthy subjects (43 males and 30 females) with a mean age of 57 years. The MRI studies were performed on a General Electric 1.5-T signa system. The spin-echo technique (T2-weighted image) was used with a pulse repetition time (TR) of 2,500 msec and echo time (TE) of 80 msec. The quantitative evaluation of cerebral infarction was assessed using personal computer and image-scanner. By MRI, the incidence of cerebral infarction in diabetic patients was significantly higher than that in healthy subjects (30.1% vs. 13.7%, respectively, p<0.05). The mean age of the diabetic patients with cerebral infarctions was higher than that of those without cerebral infarctions. Hypertension and diabetic nephropathy were present more frequently in the subjects with cerebral infarctions. These data suggest that it is important to delay the onset and slow the progression of cerebral infarction in diabetic patients by strict blood glucose control and management of blood pressure. (author).

  16. Test-retest reliability of white matter structural brain networks: A multiband diffusion MRI study

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    Tengda eZhao

    2015-02-01

    Full Text Available The multiband EPI sequence has been developed for the human connectome project to accelerate MRI data acquisition. However, no study has yet investigated the test-retest (TRT reliability of the graph metrics of white matter (WM structural brain networks constructed from this new sequence. Here, we employed a multiband diffusion MRI (dMRI dataset with repeated scanning sessions and constructed both low- and high-resolution WM networks by volume- and surface-based parcellation methods. The reproducibility of network metrics and its dependence on type of construction procedures was assessed by the intra-class correlation coefficient (ICC. We observed conserved topological architecture of WM structural networks constructed from the multiband dMRI data as previous findings from conventional dMRI. For the global network properties, the first order metrics were more reliable than second order metrics. Between two parcellation methods, networks with volume-based parcellation showed better reliability than surface-based parcellation, especially for the global metrics. Between different resolutions, the high-resolution network exhibited higher TRT performance than the low-resolution in terms of the global metrics with a large effect size, whereas the low-resolution performs better in terms of local (region and connection properties with a relatively low effect size. Moreover, we identified that the association and primary cortices showed higher reproducibility than the paralimbic/limbic regions. The important hub regions and rich-club connections are more reliable than the non-hub regions and connections. Finally, we found WM networks from the multiband dMRI showed higher reproducibility compared with those from the conventional dMRI. Together, our results demonstrated the fair to good reliability of the WM structural brain networks from the multiband EPI sequence, suggesting its potential utility for exploring individual differences and for clinical

  17. Test-retest reliability of white matter structural brain networks: a multiband diffusion MRI study.

    Science.gov (United States)

    Zhao, Tengda; Duan, Fei; Liao, Xuhong; Dai, Zhengjia; Cao, Miao; He, Yong; Shu, Ni

    2015-01-01

    The multiband EPI sequence has been developed for the human connectome project to accelerate MRI data acquisition. However, no study has yet investigated the test-retest (TRT) reliability of the graph metrics of white matter (WM) structural brain networks constructed from this new sequence. Here, we employed a multiband diffusion MRI (dMRI) dataset with repeated scanning sessions and constructed both low- and high-resolution WM networks by volume- and surface-based parcellation methods. The reproducibility of network metrics and its dependence on type of construction procedures was assessed by the intra-class correlation coefficient (ICC). We observed conserved topological architecture of WM structural networks constructed from the multiband dMRI data as previous findings from conventional dMRI. For the global network properties, the first order metrics were more reliable than second order metrics. Between two parcellation methods, networks with volume-based parcellation showed better reliability than surface-based parcellation, especially for the global metrics. Between different resolutions, the high-resolution network exhibited higher TRT performance than the low-resolution in terms of the global metrics with a large effect size, whereas the low-resolution performs better in terms of local (region and connection) properties with a relatively low effect size. Moreover, we identified that the association and primary cortices showed higher reproducibility than the paralimbic/limbic regions. The important hub regions and rich-club connections are more reliable than the non-hub regions and connections. Finally, we found WM networks from the multiband dMRI showed higher reproducibility compared with those from the conventional dMRI. Together, our results demonstrated the fair to good reliability of the WM structural brain networks from the multiband EPI sequence, suggesting its potential utility for exploring individual differences and for clinical applications.

  18. A study of brain MRI findings and clinical response of bladder empting failure in brain bladder

    Energy Technology Data Exchange (ETDEWEB)

    Miyakoda, Keiichi (Yamashina Aiseikai Hospital, Kyoto (Japan)); Watanabe, Kousuke

    1993-02-01

    In 45 patients (38 males and 7 females; average age:78 years) with brain bladder, who did not have any peripheral neuropathies and spinal disturbance, cerebral findings of MRI (1.5 T) T[sub 2] enhanced image were analyzed in comparison with those of 7 control patients with normal urination after BPH operations. Patients with neurogenic bladder were divided into three groups as follows: 33 patients with a chief complaint of urinary disturbance (Group I), 9 patients with urinary incontinence (Group II) and 3 patients with balanced bladder (Group III). High frequency of lacune (24%) of the globus pallidus and low signalling of the corpus striatum (30%) was found in Group I patients, but low frequency in other Group patients and control patients. Furthermore, pathologic changes with various grades in the globus pallidus were observed in 91% of Group I patients. In the treatment of urinary disturbance, a high improvement rate of micturition disorder (77%) was obtained in patients treated with a combination of dantrolene and TURp (TUIbn for females). However, patients who had clear lacune of the globus pallidus showed the low improvement rate. It should be possible that the globus pallidus contributes to control the movement of the external sphincter and the pelvic base muscles as well as other striated muscles. Moreover, lacune was rarely found in the urination center of the brain-stem on MRI. (author).

  19. Brain activity during driving with distraction: an immersive fMRI study

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    Tom A Schweizer

    2013-02-01

    Full Text Available Introduction: Non-invasive measurements of brain activity have an important role to play in understanding driving ability. The current study aimed to identify the neural underpinnings of human driving behavior by visualizing the areas of the brain involved in driving under different levels of demand, such as driving while distracted or making left turns at busy intersections. Methods: To capture brain activity during driving, we placed a driving simulator with a fully functional steering wheel and pedals in a 3.0 Tesla functional magnetic resonance imaging (fMRI system. To identify the brain areas involved while performing different real-world driving maneuvers, participants completed tasks ranging from simple (right turns to more complex (left turns at busy intersections. To assess the effects of driving while distracted, participants were asked to perform an auditory task while driving analogous to speaking on a hands-free device and driving. Results: A widely distributed brain network was identified, especially when making left turns at busy intersections compared to more simple driving tasks. During distracted driving, brain activation shifted dramatically from the posterior, visual and spatial areas to the prefrontal cortex. Conclusions: Our findings suggest that the distracted brain sacrificed areas in the posterior brain important for visual attention and alertness to recruit enough brain resources to perform a secondary, cognitive task. The present findings offer important new insights into the scientific understanding of the neuro-cognitive mechanisms of driving behavior and lay down an important foundation for future clinical research.

  20. Genome-wide association studies of mri-defined brain infarcts: Meta-analysis from the charge consortium

    NARCIS (Netherlands)

    S. Debette (Stéphanie); J.C. Bis (Joshua); M. Fornage (Myriam); H.A. Schmid (Herbert); M.A. Ikram (Arfan); S. Sigurdsson (Stefan); G. Heiss (Gerardo); M.V. Struchalin (Maksim); A.V. Smith (Albert Vernon); A. van der Lugt (Aad); C. DeCarli (Charles); T. Lumley (Thomas); D.S. Knopman (David); C. Enzinger (Christian); G. Eiriksdottir (Gudny); P.J. Koudstaal (Peter Jan); A.L. DeStefano (Anita); B.M. Psaty (Bruce); C. Dufouil (Carole); D.J. Catellier (Diane); F. Fazekas (Franz); T. Aspelund (Thor); Y.S. Aulchenko (Yurii); A. Beiser (Alexa); J.I. Rotter (Jerome); C. Tzourio (Christophe); D.K. Shibata (Dean); M. Tscherner (Maria); T.B. Harris (Tamara); F. Rivadeneira Ramirez (Fernando); L.D. Atwood (Larry); K. Rice (Kenneth); R.F. Gottesman (Rebecca); M.A. van Buchem (Mark); A.G. Uitterlinden (André); M. Kelly-Hayes (Margaret); M. Cushman (Mary Ann); Y. Zhu (Yicheng); E.A. Boerwinkle (Eric); V. Gudnason (Vilmundur); A. Hofman (Albert); J.R. Romero (Jose Rafael); M.M.B. Breteler (Monique); R. Schmidt (Reinhold); L.J. Launer (Lenore); W.T. Longstreth Jr

    2010-01-01

    textabstractBackground and Purpose-Previous studies examining genetic associations with MRI-defined brain infarct have yielded inconsistent findings. We investigated genetic variation underlying covert MRI infarct in persons without histories of transient ischemic attack or stroke. We performed meta

  1. Brain Activities Associated with Graphic Emoticons: An fMRI Study

    Science.gov (United States)

    Yuasa, Masahide; Saito, Keiichi; Mukawa, Naoki

    In this paper, we describe the brain activities that are associated with graphic emoticons by using functional MRI (fMRI). We use various types of faces from abstract to photorealistic in computer network applications. A graphics emoticon is an abstract face in communication over computer network. In this research, we created various graphic emoticons for the fMRI study and the graphic emoticons were classified according to friendliness and level of arousal. We investigated the brain activities of participants who were required to evaluate the emotional valence of the graphic emoticons (happy or sad). The experimental results showed that not only the right inferior frontal gyrus and the cingulate gyrus, but also the inferior and middle temporal gyrus and the fusiform gyrus, were found to be activated during the experiment. Forthermore, it is possible that the activation of the right inferior frontal gyrus and the cingulate gyrus is related to the type of abstract face. Since the inferior and middle temporal gyrus were activated, even though the graphic emoticons are static, we may perceive graphic emoticons as dynamic and living agents. Moreover, it is believed that text and graphics emoticons play an important role in enriching communication among users.

  2. A multi-contrast MRI study of microstructural brain damage in patients with mild cognitive impairment

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    C. Granziera

    2015-01-01

    Conclusion: Multi-contrast MRI appears to be a promising approach to infer pathophysiological mechanisms leading to brain tissue alterations in MCI. Likewise, parametric MRI data provide powerful correlates of cognitive deficits and improve automatic disease classification based on morphometric features.

  3. Brain activity modification produced by a single radioelectric asymmetric brain stimulation pulse: a new tool for neuropsychiatric treatments. Preliminary fMRI study

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    Castagna A

    2011-10-01

    Full Text Available Salvatore Rinaldi1,2, Vania Fontani1, Alessandro Castagna1 1Department of Neuro-Psycho-Physio Pathology, Rinaldi Fontani Institute, Florence, Italy; 2Medical School of Occupational Medicine, University of Florence, Florence, Italy Purpose: Radioelectric asymmetric brain stimulation technology with its treatment protocols has shown efficacy in various psychiatric disorders. The aim of this work was to highlight the mechanisms by which these positive effects are achieved. The current study was conducted to determine whether a single 500-millisecond radioelectric asymmetric conveyor (REAC brain stimulation pulse (BSP, applied to the ear, can effect a modification of brain activity that is detectable using functional magnetic resonance imaging (fMRI. Methods: Ten healthy volunteers, six females and four males, underwent fMRI during a simple finger-tapping motor task before and after receiving a single 500-millisecond REAC-BSP. Results: The fMRI results indicate that the average variation in task-induced encephalic activation patterns is lower in subjects following the single REAC pulse. Conclusion: The current report demonstrates that a single REAC-BSP is sufficient to modulate brain activity in awake subjects, able to be measured using fMRI. These initial results open new perspectives into the understanding of the effects of weak and brief radio pulses upon brain activity, and provide the basis for further indepth studies using REAC-BSP and fMRI. Keywords: fMRI, brain stimulation, brain modulation, REAC, neuropsychiatric treatments

  4. Mechanism of case processing in the brain: an fMRI study.

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    Satoru Yokoyama

    Full Text Available In sentence comprehension research, the case system, which is one of the subsystems of the language processing system, has been assumed to play a crucial role in signifying relationships in sentences between noun phrases (NPs and other elements, such as verbs, prepositions, nouns, and tense. However, so far, less attention has been paid to the question of how cases are processed in our brain. To this end, the current study used fMRI and scanned the brain activity of 15 native English speakers during an English-case processing task. The results showed that, while the processing of all cases activates the left inferior frontal gyrus and posterior part of the middle temporal gyrus, genitive case processing activates these two regions more than nominative and accusative case processing. Since the effect of the difference in behavioral performance among these three cases is excluded from brain activation data, the observed different brain activations would be due to the different processing patterns among the cases, indicating that cases are processed differently in our brains. The different brain activations between genitive case processing and nominative/accusative case processing may be due to the difference in structural complexity between them.

  5. The Gini coefficient: a methodological pilot study to assess fetal brain development employing postmortem diffusion MRI

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    Viehweger, Adrian; Sorge, Ina; Hirsch, Wolfgang [University Hospital Leipzig, Department of Pediatric Radiology, Leipzig (Germany); Riffert, Till; Dhital, Bibek; Knoesche, Thomas R.; Anwander, Alfred [Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Stepan, Holger [University Leipzig, Department of Obstetrics, Leipzig (Germany)

    2014-10-15

    Diffusion-weighted imaging (DWI) is important in the assessment of fetal brain development. However, it is clinically challenging and time-consuming to prepare neuromorphological examinations to assess real brain age and to detect abnormalities. To demonstrate that the Gini coefficient can be a simple, intuitive parameter for modelling fetal brain development. Postmortem fetal specimens(n = 28) were evaluated by diffusion-weighted imaging (DWI) on a 3-T MRI scanner using 60 directions, 0.7-mm isotropic voxels and b-values of 0, 150, 1,600 s/mm{sup 2}. Constrained spherical deconvolution (CSD) was used as the local diffusion model. Fractional anisotropy (FA), apparent diffusion coefficient (ADC) and complexity (CX) maps were generated. CX was defined as a novel diffusion metric. On the basis of those three parameters, the Gini coefficient was calculated. Study of fetal brain development in postmortem specimens was feasible using DWI. The Gini coefficient could be calculated for the combination of the three diffusion parameters. This multidimensional Gini coefficient correlated well with age (Adjusted R{sup 2} = 0.59) between the ages of 17 and 26 gestational weeks. We propose a new method that uses an economics concept, the Gini coefficient, to describe the whole brain with one simple and intuitive measure, which can be used to assess the brain's developmental state. (orig.)

  6. Brain's reward circuits mediate itch relief. a functional MRI study of active scratching.

    Directory of Open Access Journals (Sweden)

    Alexandru D P Papoiu

    Full Text Available Previous brain imaging studies investigating the brain processing of scratching used an exogenous intervention mimicking scratching, performed not by the subjects themselves, but delivered by an investigator. In real life, scratching is a conscious, voluntary, controlled motor response to itching, which is directed to the perceived site of distress. In this study we aimed to visualize in real-time by brain imaging the core mechanisms of the itch-scratch cycle when scratching was performed by subjects themselves. Secondly, we aimed to assess the correlations between brain patterns of activation and psychophysical ratings of itch relief or pleasurability of scratching. We also compared the patterns of brain activity evoked by self-scratching vs. passive scratching. We used a robust tridimensional Arterial Spin Labeling fMRI technique that is less sensitive to motion artifacts: 3D gradient echo and spin echo (GRASE--Propeller. Active scratching was accompanied by a higher pleasurability and induced a more pronounced deactivation of the anterior cingulate cortex and insula, in comparison with passive scratching. A significant involvement of the reward system including the ventral tegmentum of the midbrain, coupled with a mechanism deactivating the periaqueductal gray matter (PAG, suggests that itch modulation operates in reverse to the mechanism known to suppress pain. Our findings not only confirm a role for the central networks processing reward in the pleasurable aspects of scratching, but also suggest they play a role in mediating itch relief.

  7. Brain parenchymal damage in neuromyelitis optica spectrum disorder - A multimodal MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Pache, F.; Paul, F. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Zimmermann, H.; Lacheta, A.; Papazoglou, S.; Kuchling, J.; Wuerfel, J.; Brandt, A.U. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Finke, C. [Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Humboldt-Universitaet zu Berlin, Berlin School of Mind and Brain, Berlin (Germany); Hamm, B. [Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany); Ruprecht, K. [Charite Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Scheel, M. [Max Delbrueck Center for Molecular Medicine and Charite Universitaetsmedizin Berlin, NeuroCure Clinical Research Center and Experimental and Clinical Research Center, Berlin (Germany); Charite Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany)

    2016-12-15

    To investigate different brain regions for grey (GM) and white matter (WM) damage in a well-defined cohort of neuromyelitis optica spectrum disorder (NMOSD) patients and compare advanced MRI techniques (VBM, Subcortical and cortical analyses (Freesurfer), and DTI) for their ability to detect damage in NMOSD. We analyzed 21 NMOSD patients and 21 age and gender matched control subjects. VBM (GW/WM) and DTI whole brain (TBSS) analyses were performed at different statistical thresholds to reflect different statistical approaches in previous studies. In an automated atlas-based approach, Freesurfer and DTI results were compared between NMOSD and controls. DTI TBSS and DTI atlas based analysis demonstrated microstructural impairment only within the optic radiation or in regions associated with the optic radiation (posterior thalamic radiation p < 0.001, 6.9 % reduction of fractional anisotropy). VBM demonstrated widespread brain GM and WM reduction, but only at exploratory statistical thresholds, with no differences remaining after correction for multiple comparisons. Freesurfer analysis demonstrated no group differences. NMOSD specific parenchymal brain damage is predominantly located in the optic radiation, likely due to a secondary degeneration caused by ON. In comparison, DTI appears to be the most reliable and sensitive technique for brain damage detection in NMOSD. (orig.)

  8. Genome-wide association studies of mri-defined brain infarcts: Meta-analysis from the charge consortium

    OpenAIRE

    2010-01-01

    textabstractBackground and Purpose-Previous studies examining genetic associations with MRI-defined brain infarct have yielded inconsistent findings. We investigated genetic variation underlying covert MRI infarct in persons without histories of transient ischemic attack or stroke. We performed meta-analysis of genome-wide association studies of white participants in 6 studies comprising the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium. Methods-Using 2.2 mi...

  9. Enhanced brain connectivity in math-gifted adolescents: An fMRI study using mental rotation.

    Science.gov (United States)

    Prescott, James; Gavrilescu, Maria; Cunnington, Ross; O'Boyle, Michael W; Egan, Gary F

    2010-12-01

    Mathematical giftedness is a form of intelligence related to enhanced mathematical reasoning that can be tested using a variety of numerical and spatial tasks. A number of neurobiological mechanisms related to exceptional mathematical reasoning ability have been postulated, including enhanced brain connectivity. We aimed to further investigate this possibility by comparing a group of mathematically gifted adolescents with an average math ability control group performing mental rotation of complex three-dimensional block figures. Functional magnetic resonance imaging (fMRI) data were collected and differences in intrahemispheric and interhemispheric connectivity between the groups were assessed using structural equation modeling (SEM). The math-gifted showed heightened intrahemispheric frontoparietal connectivity, as well as enhanced interhemispheric frontal connectivity between the dorsolateral prefrontal and premotor cortex. These enhanced connectivity patterns are consistent with previous studies linking increased activation of the frontal and parietal regions with high fluid intelligence, and may be a unique neural characteristic of the mathematically gifted brain.

  10. Allometric scaling of brain regions to intra-cranial volume: An epidemiological MRI study.

    Science.gov (United States)

    de Jong, Laura W; Vidal, Jean-Sébastien; Forsberg, Lars E; Zijdenbos, Alex P; Haight, Thaddeus; Sigurdsson, Sigurdur; Gudnason, Vilmundur; van Buchem, Mark A; Launer, Lenore J

    2017-01-01

    There is growing evidence that sub-structures of the brain scale allometrically to total brain size, that is, in a non-proportional and non-linear way. Here, scaling of different volumes of interest (VOI) to intra-cranial volume (ICV) was examined. It was assessed whether scaling was allometric or isometric and whether scaling coefficients significantly differed from each other. We also tested to what extent allometric scaling of VOI was introduced by the automated segmentation technique. Furthermore, reproducibility of allometric scaling was studied different age groups and study populations. Study samples included samples of cognitively healthy adults from the community-based Age Gene/Environment Susceptibility-Reykjavik Study (AGES-Reykjavik Study) (N = 3,883), the Coronary Artery Risk Development in Young Adults Study (CARDIA) (N =709), and the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 180). Data encompassed participants with different age, ethnicity, risk factor profile, and ICV and VOI obtained with different automated MRI segmentation techniques. Our analysis showed that (1) allometric scaling is a trait of all parts of the brain, (2) scaling of neo-cortical white matter, neo-cortical gray matter, and deep gray matter structures including the cerebellum are significantly different from each other, and (3) allometric scaling of brain structures cannot solely be explained by age-associated atrophy, sex, ethnicity, or a systematic bias from study-specific segmentation algorithm, but appears to be a true feature of brain geometry. Hum Brain Mapp 38:151-164, 2017. © 2016 Wiley Periodicals, Inc.

  11. Brain scale-free properties in awake rest and NREM sleep: a simultaneous EEG/fMRI study.

    Science.gov (United States)

    Lei, Xu; Wang, Yulin; Yuan, Hong; Chen, Antao

    2015-03-01

    Electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) studies revealed that spontaneous activity in the brain has scale-invariant properties, as indicated by a frequency spectrum that follows a power-law distribution. However, current knowledge about the exact relationship between scaling properties in EEG and fMRI signals is very limited. To address this question, we collected simultaneous EEG-fMRI data in healthy individuals during resting wakefulness and non-rapid eye movement (NREM) sleep. For either of these conditions, we found that both EEG and fMRI power spectra followed a power-law distribution. Furthermore, the EEG and fMRI scaling exponents were highly variable across subjects, and sensitive to the choice of reference and nuisance variables in EEG and fMRI data, respectively. Interestingly, the EEG exponent of the whole brain selectively corresponded to the fMRI exponent of the thalamus during NREM sleep. Together, our findings suggest that scale-free brain activity is characterized by robust temporal structures and behavioral significance. This motivates future studies to unravel its physiological mechanisms, as well as its relevance to behavior.

  12. MRI study on reversible and irreversible electroporation induced blood brain barrier disruption.

    Directory of Open Access Journals (Sweden)

    Mohammad Hjouj

    Full Text Available Electroporation, is known to induce cell membrane permeabilization in the reversible (RE mode and cell death in the irreversible (IRE mode. Using an experimental system designed to produce a continuum of IRE followed by RE around a single electrode we used MRI to study the effects of electroporation on the brain. Fifty-four rats were injected with Gd-DOTA and treated with a G25 electrode implanted 5.5 mm deep into the striata. MRI was acquired immediately after treatment, 10 min, 20 min, 30 min, and up to three weeks following the treatment using: T1W, T2W, Gradient echo (GE, serial SPGR (DCE-MRI with flip angles ranging over 5-25°, and diffusion-weighted MRI (DWMRI. Blood brain barrier (BBB disruption was depicted as clear enhancement on T1W images. The average signal intensity in the regions of T1-enhancement, representing BBB disruption, increased from 1887±83 (arbitrary units immediately post treatment to 2246±94 20 min post treatment, then reached a plateau towards the 30 min scan where it reached 2289±87. DWMRI at 30 min showed no significant effects. Early treatment effects and late irreversible damage were clearly depicted on T2W. The enhancing volume on T2W has increased by an average of 2.27±0.27 in the first 24-48 hours post treatment, suggesting an inflammatory tissue response. The permanent tissue damage, depicted as an enhancing region on T2W, 3 weeks post treatment, decreased to an average of 50±10% of the T2W enhancing volumes on the day of the treatment which was 33±5% of the BBB disruption volume. Permanent tissue damage was significantly smaller than the volume of BBB disruption, suggesting, that BBB disruption is associated with RE while tissue damage with IRE. These results demonstrate the feasibility of applying reversible and irreversible electroporation for transient BBB disruption or permanent damage, respectively, and applying MRI for planning/monitoring disruption volume/shape by optimizing electrode positions

  13. Reliability of semiquantitative {sup 18}F-FDG PET parameters derived from simultaneous brain PET/MRI: A feasibility study

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    Jena, Amarnath, E-mail: drjena2002@yahoo.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Taneja, Sangeeta, E-mail: s_taneja1974@yahoo.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Goel, Reema, E-mail: reemagoell@gmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Renjen, Pushpendranath, E-mail: pnrenjen@hotmail.com [Department of Neurology, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India); Negi, Pradeep, E-mail: pradeepmri@rediffmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Mathura Road, New Delhi 110076, Delhi (India)

    2014-07-15

    Purpose: Simultaneous brain PET/MRI faces an important issue of validation of accurate MRI based attenuation correction (AC) method for precise quantitation of brain PET data unlike in PET/CT systems where the use of standard, validated CT based AC is routinely available. The aim of this study was to investigate the feasibility of evaluation of semiquantitative {sup 18}F-FDG PET parameters derived from simultaneous brain PET/MRI using ultrashort echo time (UTE) sequences for AC and to assess their agreement with those obtained from PET/CT examination. Methods: Sixteen patients (age range 18–73 years; mean age 49.43 (19.3) years; 13 men 3 women) underwent simultaneous brain PET/MRI followed immediately by PET/CT. Quantitative analysis of brain PET images obtained from both studies was undertaken using Scenium v.1 brain analysis software package. Twenty ROIs for various brain regions were system generated and 6 semiquantitative parameters including maximum standardized uptake value (SUV max), SUV mean, minimum SUV (SUV min), minimum standard deviation (SD min), maximum SD (SD max) and SD from mean were calculated for both sets of PET data for each patient. Intra-class correlation coefficients (ICCs) were determined to assess agreement between the various semiquantitative parameters for the two PET data sets. Results: Intra-class co-relation between the two PET data sets for SUV max, SUV mean and SD max was highly significant (p < 0.00) for all the 20 predefined brain regions with ICC > 0.9. SD from mean was also found to be statistically significant for all the predefined brain regions with ICC > 0.8. However, SUV max and SUV mean values obtained from PET/MRI were significantly lower compared to those of PET/CT for all the predefined brain regions. Conclusion: PET quantitation accuracy using the MRI based UTE sequences for AC in simultaneous brain PET/MRI is reliable in a clinical setting, being similar to that obtained using PET/CT.

  14. Brain MRI abnormalities in the adult form of myotonic dystrophy type 1: A longitudinal case series study.

    Science.gov (United States)

    Conforti, Renata; de Cristofaro, Mario; Cristofano, Adriana; Brogna, Barbara; Sardaro, Angela; Tedeschi, Gioacchino; Cirillo, Sossio; Di Costanzo, Alfonso

    2016-02-01

    This study aimed to verify whether brain abnormalities, previously described in patients with myotonic dystrophy type 1 (DM1) by magnetic resonance imaging (MRI), progressed over time and, if so, to characterize their progression. Thirteen DM1 patients, who had at least two MRI examinations, were retrospectively evaluated and included in the study. The mean duration (± standard deviation) of follow-up was 13.4 (±3.8) years, over a range of 7-20 years. White matter lesions (WMLs) were rated by semi-quantitative method, the signal intensity of white matter poster-superior to trigones (WMPST) by reference to standard images and brain atrophy by ventricular/brain ratio (VBR). At the end of MRI follow-up, the scores relative to lobar, temporal and periventricular WMLs, to WMPST signal intensity and to VBR were significantly increased compared to baseline, and MRI changes were more evident in some families than in others. No correlation was found between the MRI changes and age, onset, disease duration, muscular involvement, CTG repetition and follow-up duration. These results demonstrated that white matter involvement and brain atrophy were progressive in DM1 and suggested that progression rate varied from patient to patient, regardless of age, disease duration and genetic defect.

  15. The effects of aging on the brain activation pattern during a speech perception task: an fMRI study.

    Science.gov (United States)

    Manan, Hanani Abdul; Franz, Elizabeth A; Yusoff, Ahmad Nazlim; Mukari, Siti Zamratol-Mai Sarah

    2015-02-01

    In the present study, brain activation associated with speech perception processing was examined across four groups of adult participants with age ranges between 20 and 65 years, using functional MRI (fMRI). Cognitive performance demonstrates that performance accuracy declines with age. fMRI results reveal that all four groups of participants activated the same brain areas. The same brain activation pattern was found in all activated areas (except for the right superior temporal gyrus and right middle temporal gyrus); brain activity was increased from group 1 (20-29 years) to group 2 (30-39 years). However, it decreased in group 3 (40-49 years) with further decreases in group 4 participants (50-65 years). Result also reveals that three brain areas (superior temporal gyrus, Heschl's gyrus and cerebellum) showed changes in brain laterality in the older participants, akin to a shift from left-lateralized to right-lateralized activity. The onset of this change was different across brain areas. Based on these findings we suggest that, whereas all four groups of participants used the same areas in processing, the engagement and recruitment of those areas differ with age as the brain grows older. Findings are discussed in the context of corroborating evidence of neural changes with age.

  16. Effects of overnight fasting on working memory-related brain network: an fMRI study.

    Science.gov (United States)

    Chechko, Natalia; Vocke, Sebastian; Habel, Ute; Toygar, Timur; Kuckartz, Lisa; Berthold-Losleben, Mark; Laoutidis, Zacharias G; Orfanos, Stelios; Wassenberg, Annette; Karges, Wölfram; Schneider, Frank; Kohn, Nils

    2015-03-01

    Glucose metabolism serves as the central source of energy for the human brain. Little is known about the effects of blood glucose level (BGL) on higher-order cognitive functions within a physiological range (e.g., after overnight fasting). In this randomized, placebo-controlled, double blind study, we assessed the impact of overnight fasting (14 h) on brain activation during a working memory task. We sought to mimic BGLs that occur naturally in healthy humans after overnight fasting. After standardized periods of food restriction, 40 (20 male) healthy participants were randomly assigned to receive either glucagon to balance the BGL or placebo (NaCl). A parametric fMRI paradigm, including 2-back and 0-back tasks, was used. Subclinically low BGL following overnight fasting was found to be linked to reduced involvement of the bilateral dorsal midline thalamus and the bilateral basal ganglia, suggesting high sensitivity of those regions to minimal changes in BGLs. Our results indicate that overnight fasting leads to physiologically low levels of glucose, impacting brain activation during working memory tasks even when there are no differences in cognitive performance.

  17. Haptic fMRI: combining functional neuroimaging with haptics for studying the brain's motor control representation.

    Science.gov (United States)

    Menon, Samir; Brantner, Gerald; Aholt, Chris; Kay, Kendrick; Khatib, Oussama

    2013-01-01

    A challenging problem in motor control neuroimaging studies is the inability to perform complex human motor tasks given the Magnetic Resonance Imaging (MRI) scanner's disruptive magnetic fields and confined workspace. In this paper, we propose a novel experimental platform that combines Functional MRI (fMRI) neuroimaging, haptic virtual simulation environments, and an fMRI-compatible haptic device for real-time haptic interaction across the scanner workspace (above torso ∼ .65×.40×.20m(3)). We implement this Haptic fMRI platform with a novel haptic device, the Haptic fMRI Interface (HFI), and demonstrate its suitability for motor neuroimaging studies. HFI has three degrees-of-freedom (DOF), uses electromagnetic motors to enable high-fidelity haptic rendering (>350Hz), integrates radio frequency (RF) shields to prevent electromagnetic interference with fMRI (temporal SNR >100), and is kinematically designed to minimize currents induced by the MRI scanner's magnetic field during motor displacement (haptically transparent and does not interfere with human motor tasks (tested for .4m reaches). By allowing fMRI experiments involving complex three-dimensional manipulation with haptic interaction, Haptic fMRI enables-for the first time-non-invasive neuroscience experiments involving interactive motor tasks, object manipulation, tactile perception, and visuo-motor integration.

  18. Brain MRI CO2 stress testing: a pilot study in patients with concussion.

    Directory of Open Access Journals (Sweden)

    W Alan C Mutch

    Full Text Available There is a real need for quantifiable neuro-imaging biomarkers in concussion. Here we outline a brain BOLD-MRI CO2 stress test to assess the condition.This study was approved by the REB at the University of Manitoba. A group of volunteers without prior concussion were compared to post-concussion syndrome (PCS patients--both symptomatic and recovered asymptomatic. Five 3-minute periods of BOLD imaging at 3.0 T were studied--baseline 1 (BL1--at basal CO2 tension, hypocapnia (CO2 decreased ∼5 mmHg, BL2, hypercapnia (CO2 increased ∼10 mmHg and BL3. Data were processed using statistical parametric mapping (SPM for 1st level analysis to compare each subject's response to the CO2 stress at the p = 0.001 level. A 2nd level analysis compared each PCS patient's response to the mean response of the control subjects at the p = 0.05 level.We report on 5 control subjects, 8 symptomatic and 4 asymptomatic PCS patients. Both increased and decreased response to CO2 was seen in all PCS patients in the 2nd level analysis. The responses were quantified as reactive voxel counts: whole brain voxel counts (2.0±1.6%, p = 0.012 for symptomatic patients for CO2 response controls: 0.49±0.31%, p = 0.053 for asymptomatic patients for CO2 response controls.Quantifiable alterations in regional cerebrovascular responsiveness are present in concussion patients during provocative CO2 challenge and BOLD MRI and not in healthy controls. Future longitudinal studies must aim to clarify the relationship between CO2 responsiveness and individual patient symptoms and outcomes.

  19. The Brain Functional State of Music Creation: an fMRI Study of Composers.

    Science.gov (United States)

    Lu, Jing; Yang, Hua; Zhang, Xingxing; He, Hui; Luo, Cheng; Yao, Dezhong

    2015-07-23

    In this study, we used functional magnetic resonance imaging (fMRI) to explore the functional networks in professional composers during the creation of music. We compared the composing state and resting state imagery of 17 composers and found that the functional connectivity of primary networks in the bilateral occipital lobe and bilateral postcentral cortex decreased during the composing period. However, significantly stronger functional connectivity appeared between the anterior cingulate cortex (ACC), the right angular gyrus and the bilateral superior frontal gyrus during composition. These findings indicate that a specific brain state of musical creation is formed when professional composers are composing, in which the integration of the primary visual and motor areas is not necessary. Instead, the neurons of these areas are recruited to enhance the functional connectivity between the ACC and the default mode network (DMN) to plan the integration of musical notes with emotion.

  20. Transient Ischemic Attacks and Presence of an Acute Brain Lesion in Diffusion-Weighted MRI: Study of 50 Patients

    Directory of Open Access Journals (Sweden)

    SM Paknejad

    2012-10-01

    Full Text Available Background: Finding an acute brain lesion by diffusion-weighted (DW MRI upon an episode of transient ischemic attack (TIA is a predictor of imminent stroke in the near future. Therefore, exploring risk factors associated with lesions in DW-MRI of the brain is important in adopting an approach to TIA management. In the current study, we tried to determine the risk factors associated with lesions in DW-MRI of the brain in patients experiencing TIA episodes.Methods: Fifty patients with TIA were recruited consecutively in Sina Hospital, Tehran, Iran, over a 6-month period between July 2008 and January 2009. All of the patients underwent a complete neurological examination and laboratory tests. Brain DW-MRIs were performed for all the patients within 72 hours of a TIA episode.Results: DW-MRI revealed an acute lesion in 16% of the participants. There was a significant correlation between presence of an acute lesion in DW-MRI and TIA duration, history of diabetes mellitus and presence of unilateral facial palsy (P=0.0003, P=0.02 and P=0.008, respectively. Other variables such as age, hypertension, hyperlipidemia, past history of TIA, headache, vertigo, and sensory or visual disturbances had no significant relation with the presence of an acute lesion in DW-MRI.Conclusion: Duration of TIA, presence of diabetes mellitus and unilateral facial palsy are risk factors for an acute lesion in DW-MRI, meaning that patients with such risk factors are at risk for stroke in the near future.

  1. Recent applications of UHF-MRI in the study of human brain function and structure : a review

    NARCIS (Netherlands)

    Van der Zwaag, W.; Schäfer, Andreas; Marques, José P; Turner, R.; Trampel, Robert

    2016-01-01

    The increased availability of ultra-high-field (UHF) MRI has led to its application in a wide range of neuroimaging studies, which are showing promise in transforming fundamental approaches to human neuroscience. This review presents recent work on structural and functional brain imaging, at 7 T and

  2. Asymmetric Processing of Numerical and Nonnumerical Magnitudes in the Brain: An fMRI Study.

    Science.gov (United States)

    Leibovich, Tali; Vogel, Stephan E; Henik, Avishai; Ansari, Daniel

    2016-01-01

    It is well established that, when comparing nonsymbolic magnitudes (e.g., dot arrays), adults can use both numerical (i.e., the number of items) and nonnumerical (density, total surface areas, etc.) magnitudes. It is less clear which of these magnitudes is more salient or processed more automatically. In this fMRI study, we used a nonsymbolic comparison task to ask if different brain areas are responsible for the automatic processing of numerical and nonnumerical magnitudes, when participants were instructed to attend to either the numerical or the nonnumerical magnitudes of the same stimuli. An interaction of task (numerical vs. nonnumerical) and congruity (congruent vs. incongruent) was found in the right TPJ. Specifically, this brain region was more strongly activated during numerical processing when the nonnumerical magnitudes were negatively correlated with numerosity (incongruent trials). In contrast, such an interference effect was not evident during nonnumerical processing when the task-irrelevant numerical magnitude was incongruent. In view of the role of the right TPJ in the control of stimulus-driven attention, we argue that these data demonstrate that the processing of nonnumerical magnitudes is more automatic than that of numerical magnitudes and that, therefore, the influence of numerical and nonnumerical variables on each other is asymmetrical.

  3. Cerebral blood flow modulation insufficiency in brain networks in multiple sclerosis: A hypercapnia MRI study.

    Science.gov (United States)

    Marshall, Olga; Chawla, Sanjeev; Lu, Hanzhang; Pape, Louise; Ge, Yulin

    2016-12-01

    Cerebrovascular reactivity measures vascular regulation of cerebral blood flow and is responsible for maintaining healthy neurovascular coupling. Multiple sclerosis exhibits progressive neurodegeneration and global cerebrovascular reactivity deficits. This study investigates varied degrees of cerebrovascular reactivity impairment in different brain networks, which may be an underlying cause for functional changes in the brain, affecting long-distance projection integrity and cognitive function; 28 multiple sclerosis and 28 control subjects underwent pseudocontinuous arterial spin labeling perfusion MRI to measure cerebral blood flow under normocapnia (room air) and hypercapnia (5% carbon dioxide gas mixture) breathing. Cerebrovascular reactivity, measured as normocapnic to hypercapnic cerebral blood flow percent increase normalized by end-tidal carbon dioxide change, was determined from seven functional networks (default mode, frontoparietal, somatomotor, visual, limbic, dorsal, and ventral attention networks). Group analysis showed significantly decreased cerebrovascular reactivity in patients compared to controls within the default mode, frontoparietal, somatomotor, and ventral attention networks after multiple comparison correction. Regression analysis showed a significant correlation of cerebrovascular reactivity with lesion load in the default mode and ventral attention networks and with gray matter atrophy in the default mode network. Functional networks in multiple sclerosis patients exhibit varied amounts of cerebrovascular reactivity deficits. Such blood flow regulation abnormalities may contribute to functional communication disruption in multiple sclerosis.

  4. Gender differences in brain development in Chinese children and adolescents: a structural MRI study

    Science.gov (United States)

    Guo, Xiaojuan; Jin, Zhen; Chen, Kewei; Peng, Danling; Yao, Li

    2008-03-01

    Using optimized voxel-based morphometry (VBM), this study systematically investigated gender differences in brain development through magnetic resonance imaging (MRI) data in 158 Chinese normal children and adolescents aged 7.26 to 22.80 years (mean age 15.03+/-4.70 years, 78 boys and 80 girls). Gender groups were matched for measures of age, handedness, education level. The customized brain templates, including T I-weighted image and gray matter (GM)/white matter (WM)/cerebro-spinal fluid (CSF) prior probability maps, were created from all participants. Results showed that the total intracranial volume (TIV), global absolute GM and global WM volume in girls were significantly smaller than those in boys. The hippocampus grew faster in girls than that in boys, but the amygdala grew faster in boys than that in girls. The rate of regional GM decreases with age was steeper in the left superior parietal lobule, bilateral inferior parietal lobule, left precuneus, and bilateral supramarginal gyrus in boys compared to girls, which was possibly related to better spatial processing ability in boys. Regional GM volumes were greater in bilateral superior temporal gyrus, bilateral inferior frontal gyrus and bilateral middle frontal gyrus in girls. Regional WM volumes were greater in the left temporal lobe, right inferior parietal and bilateral middle frontal gyrus in girls. The gender differences in the temporal and frontal lobe maybe be related to better language ability in girls. These findings may aid in understanding the differences in cognitive function between boys and girls.

  5. Hemisphere- and gender-related differences in small-world brain networks: a resting-state functional MRI study.

    Science.gov (United States)

    Tian, Lixia; Wang, Jinhui; Yan, Chaogan; He, Yong

    2011-01-01

    We employed resting-state functional MRI (R-fMRI) to investigate hemisphere- and gender-related differences in the topological organization of human brain functional networks. Brain networks were first constructed by measuring inter-regional temporal correlations of R-fMRI data within each hemisphere in 86 young, healthy, right-handed adults (38 males and 48 females) followed by a graph-theory analysis. The hemispheric networks exhibit small-world attributes (high clustering and short paths) that are compatible with previous results in the whole-brain functional networks. Furthermore, we found that compared with females, males have a higher normalized clustering coefficient in the right hemispheric network but a lower clustering coefficient in the left hemispheric network, suggesting a gender-hemisphere interaction. Moreover, we observed significant hemisphere-related differences in the regional nodal characteristics in various brain regions, such as the frontal and occipital regions (leftward asymmetry) and the temporal regions (rightward asymmetry), findings that are consistent with previous studies of brain structural and functional asymmetries. Together, our results suggest that the topological organization of human brain functional networks is associated with gender and hemispheres, and they provide insights into the understanding of functional substrates underlying individual differences in behaviors and cognition.

  6. Real-time fMRI in neuroscience research and its use in studying the aging brain

    Directory of Open Access Journals (Sweden)

    Mohit Rana

    2016-10-01

    Full Text Available Cognitive decline is a major concern in the aging population. It is normative to experience some deterioration in cognitive abilities with advanced age such as related to memory performance, attention distraction to interference, task switching, and processing speed. However, intact cognitive functioning in old age is important for leading an independent day-to-day life. Thus, studying ways to counteract or delay the onset of cognitive decline in aging is crucial. The literature offers various explanations for the decline in cognitive performance in aging; among those are age-related gray and white matter atrophy, synaptic degeneration, blood flow reduction, neurochemical alterations and change in connectivity patterns with advanced age. An emerging literature on neurofeedback and Brain Computer Interface (BCI reports exciting results supporting the benefits of volitional modulation of brain activity on cognition and behavior. Neurofeedback studies based on real-time functional magnetic resonance imaging (rtfMRI have shown behavioral changes in schizophrenia and behavioral benefits in nicotine addiction. This article integrates research on cognitive and brain aging with evidence of brain and behavioral modification due to rtfMRI neurofeedback. We offer a state-of-the-art description of the rtfMRI technique with an eye towards its application in aging. We present preliminary results of a feasibility study exploring the possibility of using rtfMRI to train older adults to volitionally control brain activity. Based on these first findings, we discuss possible implementations of rtfMRI neurofeedback as a novel technique to study and alleviate cognitive decline in healthy and pathological aging.

  7. Real-Time fMRI in Neuroscience Research and Its Use in Studying the Aging Brain

    Science.gov (United States)

    Rana, Mohit; Varan, Andrew Q.; Davoudi, Anis; Cohen, Ronald A.; Sitaram, Ranganatha; Ebner, Natalie C.

    2016-01-01

    Cognitive decline is a major concern in the aging population. It is normative to experience some deterioration in cognitive abilities with advanced age such as related to memory performance, attention distraction to interference, task switching, and processing speed. However, intact cognitive functioning in old age is important for leading an independent day-to-day life. Thus, studying ways to counteract or delay the onset of cognitive decline in aging is crucial. The literature offers various explanations for the decline in cognitive performance in aging; among those are age-related gray and white matter atrophy, synaptic degeneration, blood flow reduction, neurochemical alterations, and change in connectivity patterns with advanced age. An emerging literature on neurofeedback and Brain Computer Interface (BCI) reports exciting results supporting the benefits of volitional modulation of brain activity on cognition and behavior. Neurofeedback studies based on real-time functional magnetic resonance imaging (rtfMRI) have shown behavioral changes in schizophrenia and behavioral benefits in nicotine addiction. This article integrates research on cognitive and brain aging with evidence of brain and behavioral modification due to rtfMRI neurofeedback. We offer a state-of-the-art description of the rtfMRI technique with an eye towards its application in aging. We present preliminary results of a feasibility study exploring the possibility of using rtfMRI to train older adults to volitionally control brain activity. Based on these first findings, we discuss possible implementations of rtfMRI neurofeedback as a novel technique to study and alleviate cognitive decline in healthy and pathological aging. PMID:27803662

  8. A reliability study on brain activation during active and passive arm movements supported by an MRI-compatible robot.

    Science.gov (United States)

    Estévez, Natalia; Yu, Ningbo; Brügger, Mike; Villiger, Michael; Hepp-Reymond, Marie-Claude; Riener, Robert; Kollias, Spyros

    2014-11-01

    In neurorehabilitation, longitudinal assessment of arm movement related brain function in patients with motor disability is challenging due to variability in task performance. MRI-compatible robots monitor and control task performance, yielding more reliable evaluation of brain function over time. The main goals of the present study were first to define the brain network activated while performing active and passive elbow movements with an MRI-compatible arm robot (MaRIA) in healthy subjects, and second to test the reproducibility of this activation over time. For the fMRI analysis two models were compared. In model 1 movement onset and duration were included, whereas in model 2 force and range of motion were added to the analysis. Reliability of brain activation was tested with several statistical approaches applied on individual and group activation maps and on summary statistics. The activated network included mainly the primary motor cortex, primary and secondary somatosensory cortex, superior and inferior parietal cortex, medial and lateral premotor regions, and subcortical structures. Reliability analyses revealed robust activation for active movements with both fMRI models and all the statistical methods used. Imposed passive movements also elicited mainly robust brain activation for individual and group activation maps, and reliability was improved by including additional force and range of motion using model 2. These findings demonstrate that the use of robotic devices, such as MaRIA, can be useful to reliably assess arm movement related brain activation in longitudinal studies and may contribute in studies evaluating therapies and brain plasticity following injury in the nervous system.

  9. Brain MRI abnormalities in neuromyelitis optica

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    Wang Fei, E-mail: feiwang1973@gmail.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Liu Yaou, E-mail: asiaeurope80@gmail.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Duan Yunyun, E-mail: duanyun2003@sohu.com [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Li Kuncheng, E-mail: kunchengli@yahoo.com.cn [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China); Education Ministry Key Laboratory for Neurodegenerative Disease, Xuanwu Hospital, Capital University of Medical Sciences, 45 Chang-Chun St, Xuanwu District, Beijing 100053 (China)

    2011-11-15

    Objective: The purpose of this study was to explore brain MRI findings in neuromyelitis optica (NMO) and to investigate specific brain lesions with respect to the localization of aquaporin-4 (AQP-4). Materials and methods: Forty admitted patients (36 women) who satisfied the 2006 criteria of Wingerchuk et al. for NMO were included in this study. All patients received a neurological examination and MRI scanning including brain and spinal cord. MRIs were classified as normal, nonspecific, multiple sclerosis-like, typical abnormalities. MS-like lesions were too few to satisfy the Barkhof et al. criteria for MS. Confluent lesions involving high AQP-4 regions were considered typical. Non-enhancing deep white matter lesions other than MS-like lesions or typical lesions were classified as nonspecific. Results: Brain MRI lesions were delineated in 12 patients (25%). Four patients (10%) had hypothalamus, brainstem or periventricle lesions. Six (15%) patients were nonspecific, and 2 (5%) patients had multiple sclerosis-like lesions. Conclusion: Brain MRIs are negative in most NMO, and brain lesions do not exclude the diagnosis of NMO. Hypothalamus, brainstem or periventricle lesions, corresponding to high sites of AQP-4 in the brain, are indicative of lesions of NMO.

  10. Prevalence of lateral ventricle asymmetry in brain MRI studies of neurologically normal dogs and dogs with idiopathic epilepsy.

    Science.gov (United States)

    Pivetta, Mauro; De Risio, Luisa; Newton, Richard; Dennis, Ruth

    2013-01-01

    Asymmetry of the cerebral lateral ventricles is a common finding in cross-sectional imaging of otherwise normal canine brains and has been assumed to be incidental. The purpose of this retrospective study was to compare the prevalence of ventricular asymmetry in brain MRI studies of normal dogs and dogs with idiopathic epilepsy. Brain MRI archives were searched for 100 neurologically normal dogs (Group 1) and 100 dogs with idiopathic epilepsy (Group 2). For each dog, asymmetry of the lateral ventricles was subjectively classified as absent, mild, moderate, and severe based on a consensus of two observers who were unaware of group status. Ventricular areas were measured from transverse T1W images at the level of the interthalamic adhesion. An asymmetry ratio was calculated as the ratio of the larger to smaller ventricular transverse area. There was excellent agreement between subjective assessments of ventricular asymmetry and quantitative assessments using asymmetry ratios (k = 0.995). The prevalence of asymmetry was 38% in Group 1 dogs and 44% in Group 2 dogs. Assymmetry was scored as mild in the majority of Group 2 dogs. There was no significant association between presence/absence and degree of ventricular asymmetry vs. dog group, age, gender, or skull conformation. Findings from the current study supported previously published assumptions that asymmetry of the lateral cerebral ventricles is an incidental finding in MRI studies of the canine brain.

  11. Brain Activity During Cocaine Craving and Gambling Urges: An fMRI Study.

    Science.gov (United States)

    Kober, Hedy; Lacadie, Cheryl M; Wexler, Bruce E; Malison, Robert T; Sinha, Rajita; Potenza, Marc N

    2016-01-01

    Although craving states are important to both cocaine dependence (CD) and pathological gambling (PG), few studies have directly investigated neurobiological similarities and differences in craving between these disorders. We used functional magnetic resonance imaging (fMRI) to assess brain activity in 103 participants (30 CD, 28 PG, and 45 controls) while they watched videos depicting cocaine, gambling, and sad scenarios to investigate the neural correlates of craving. We observed a three-way urge type × video type × diagnostic group interaction in self-reported craving, with CD participants reporting strong cocaine cravings to cocaine videos, and PG participants reporting strong gambling urges to gambling videos. Neuroimaging data revealed a diagnostic group × video interaction in anterior cingulate cortex/ventromedial prefrontal cortex (mPFC), activating predominantly to cocaine videos in CD participants, and a more dorsal mPFC region that was most strongly activated for cocaine videos in CD participants, gambling videos in PG participants, and sad videos in control participants. Gender × diagnosis × video interactions identified dorsal mPFC and a region in posterior insula/caudate in which female but not male PG participants showed increased responses to gambling videos. Findings illustrate both similarities and differences in the neural correlates of drug cravings and gambling urges in CD and PG. Future studies should investigate diagnostic- and gender-specific therapies targeting the neural systems implicated in craving/urge states in addictions.

  12. Altered brain functions in HIV positive patients free of HIV- associated neurocognitive disorders: A MRI study during unilateral hand movements

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    Jing Zhao

    2015-03-01

    Full Text Available This paper aimed to investigate the brain activity of human immunodeficiency virus (HIV positive patients with normal cognition during unilateral hand movement and whether highly active antiretroviral therapy (HAART could affect the brain function. Functional magnetic resonance imaging (fMRI was performed for 60 HIV positive (HIV+ subjects and −42 healthy age-matched right-handed control subjects. Each subject was evaluated by the neuropsychological test and examined with fMRI during left and right hand movement tasks. HIV+ subjects showed greater activation in anterior cingulum, precuneus, occipital lobes, ipsilateral postcentral gyrus and contralateral cerebellum compared with control group during right hand movement task. However, during left hand movement no statistically significant difference was detected between these two groups. HAART medication for HIV+ subjects lowered the increased activity to normal level. Meanwhile patients receiving the regimen of zidovudine, lamivudine and efavirenz showed lower activity at bilateral caudate and ipsilateral inferior frontal gyrus in comparison with subjects receiving other HAART regimens. Therefore, HIV+ subjects demonstrated brain asymmetry in motor cortex, with increased activity present during right hand movement but absent during left hand movement. HAART proves effective in HIV+ subjects even with normal cognition and the specific regimen of HAART could prevent cerebral abnormal functions. Meanwhile, this study validates that during motor tasks, fMRI can detect the brain signal changes prior to the occurrences of other HIV- associated dysfunctions.

  13. Mild cognitive impairment and fMRI studies of brain functional connectivity: the state of the art

    Science.gov (United States)

    Farràs-Permanyer, Laia; Guàrdia-Olmos, Joan; Peró-Cebollero, Maribel

    2015-01-01

    In the last 15 years, many articles have studied brain connectivity in Mild Cognitive Impairment patients with fMRI techniques, seemingly using different connectivity statistical models in each investigation to identify complex connectivity structures so as to recognize typical behavior in this type of patient. This diversity in statistical approaches may cause problems in results comparison. This paper seeks to describe how researchers approached the study of brain connectivity in MCI patients using fMRI techniques from 2002 to 2014. The focus is on the statistical analysis proposed by each research group in reference to the limitations and possibilities of those techniques to identify some recommendations to improve the study of functional connectivity. The included articles came from a search of Web of Science and PsycINFO using the following keywords: f MRI, MCI, and functional connectivity. Eighty-one papers were found, but two of them were discarded because of the lack of statistical analysis. Accordingly, 79 articles were included in this review. We summarized some parts of the articles, including the goal of every investigation, the cognitive paradigm and methods used, brain regions involved, use of ROI analysis and statistical analysis, emphasizing on the connectivity estimation model used in each investigation. The present analysis allowed us to confirm the remarkable variability of the statistical analysis methods found. Additionally, the study of brain connectivity in this type of population is not providing, at the moment, any significant information or results related to clinical aspects relevant for prediction and treatment. We propose to follow guidelines for publishing fMRI data that would be a good solution to the problem of study replication. The latter aspect could be important for future publications because a higher homogeneity would benefit the comparison between publications and the generalization of results. PMID:26300802

  14. Mild cognitive impairment and fMRI studies of brain functional connectivity: the state of the art

    Directory of Open Access Journals (Sweden)

    Laia eFarràs-Permanyer

    2015-08-01

    Full Text Available In the last fifteen years, many articles have studied brain connectivity in Mild Cognitive Impairment patients with fMRI techniques, seemingly using different connectivity statistical models in each investigation to identify complex connectivity structures so as to recognize typical behavior in this type of patient. This diversity in statistical approaches may cause problems in results comparison. This paper seeks to describe how researchers approached the study of brain connectivity in MCI patients using fMRI techniques from 2002 to 2014.The focus is on the statistical analysis proposed by each research group in reference to the limitations and possibilities of those techniques to identify some recommendations to improve the study of functional connectivity. The included articles came from a search of Web of Science and PsycINFO using the following keywords: fMRI, MCI and functional connectivity. Eighty-one papers were found, but 2 of them were discarded because of the lack of statistical analysis. Accordingly, 79 articles were included in this review. We summarized some parts of the articles, including the goal of every investigation, the cognitive paradigm and methods used, brain regions involved, use of ROI analysis and statistical analysis, emphasizing on the connectivity estimation model used in each investigation. The present analysis allowed us to confirm the remarkable variability of the statistical analysis methods found. Additionally, the study of brain connectivity in this type of population is not providing, at the moment, any significant information or results related to clinical aspects relevant for prediction and treatment. We propose to follow guidelines for publishing fMRI data that would be a good solution to the problem of study replication. The latter aspect could be important for future publications because a higher homogeneity would benefit the comparison between publications and the generalization of results.

  15. Mild cognitive impairment and fMRI studies of brain functional connectivity: the state of the art.

    Science.gov (United States)

    Farràs-Permanyer, Laia; Guàrdia-Olmos, Joan; Peró-Cebollero, Maribel

    2015-01-01

    In the last 15 years, many articles have studied brain connectivity in Mild Cognitive Impairment patients with fMRI techniques, seemingly using different connectivity statistical models in each investigation to identify complex connectivity structures so as to recognize typical behavior in this type of patient. This diversity in statistical approaches may cause problems in results comparison. This paper seeks to describe how researchers approached the study of brain connectivity in MCI patients using fMRI techniques from 2002 to 2014. The focus is on the statistical analysis proposed by each research group in reference to the limitations and possibilities of those techniques to identify some recommendations to improve the study of functional connectivity. The included articles came from a search of Web of Science and PsycINFO using the following keywords: f MRI, MCI, and functional connectivity. Eighty-one papers were found, but two of them were discarded because of the lack of statistical analysis. Accordingly, 79 articles were included in this review. We summarized some parts of the articles, including the goal of every investigation, the cognitive paradigm and methods used, brain regions involved, use of ROI analysis and statistical analysis, emphasizing on the connectivity estimation model used in each investigation. The present analysis allowed us to confirm the remarkable variability of the statistical analysis methods found. Additionally, the study of brain connectivity in this type of population is not providing, at the moment, any significant information or results related to clinical aspects relevant for prediction and treatment. We propose to follow guidelines for publishing fMRI data that would be a good solution to the problem of study replication. The latter aspect could be important for future publications because a higher homogeneity would benefit the comparison between publications and the generalization of results.

  16. Intrinsic brain connectivity in chronic pain: A resting-state fMRI study in patients with rheumatoid arthritis.

    Directory of Open Access Journals (Sweden)

    Pär eFlodin

    2016-03-01

    Full Text Available AbstractBackground. Rheumatoid arthritis (RA is commonly accompanied by pain that is discordant with the degree of peripheral pathology. Very little is known about the cerebral processes involved in pain processing in RA. Here we investigated resting-state brain connectivity associated with prolonged pain in RA. Methods. 24 RA subjects and 19 matched controls were compared with regard to both behavioral measures of pain perception and resting-resting state fMRI data acquired subsequently to fMRI sessions involving pain stimuli. The resting-state fMRI brain connectivity was investigated using 159 seed regions located in cardinal pain processing brain regions. Additional principal component based multivariate pattern analysis of the whole brain connectivity pattern was carried out in a data driven analysis to localize group differences in functional connectivity. Results. When RA patients were compared to controls, we observed significantly lower pain resilience for pressure on the affected finger joints (i.e. P50-joint and an overall heightened level of perceived global pain in RA patients. Relative to controls, RA patients displayed increased brain connectivity predominately for the supplementary motor areas, mid-cingulate cortex and the primary sensorimotor cortex. Additionally, we observed an increase in brain connectivity between the insula and prefrontal cortex as well as between anterior cingulate cortex and occipital areas for RA patients. None of the group differences in brain connectivity were significantly correlated with behavioral parameters.Conclusion. Our study provides experimental evidence of increased connectivity between frontal midline regions that are implicated in affective pain processing and bilateral sensorimotor regions in RA patients.

  17. Pathological and incidental findings on brain MRI in a single-center study of 229 consecutive girls with early or precocious puberty.

    Directory of Open Access Journals (Sweden)

    Signe Sloth Mogensen

    Full Text Available UNLABELLED: Central precocious puberty may result from organic brain lesions, but is most frequently of idiopathic origin. Clinical or biochemical factors which could predict a pathological brain MRI in girls with CPP have been searched for. With the recent decline in age at pubertal onset among US and European girls, it has been suggested that only girls with CPP below 6 years of age should have brain MRI performed. OBJECTIVE: To evaluate the outcome of brain MRI in girls referred with early signs of puberty in relation to age at presentation as well as clinical and biochemical parameters. METHOD: A single-center study of 229 consecutive girls with early or precocious puberty who had brain imaging performed. We evaluated medical history, clinical and biochemical factors, and four groups were defined based on the outcome of their MRI. RESULTS: Thirteen out of 208 (6.3% girls with precocious puberty, but no other sign of CNS symptoms, had a pathological brain MRI. Importantly, all 13 girls were above 6 years of age, and 6 girls were even 8-9 years old. Twenty girls (9.6% had incidental findings on brain MRI. Furthermore, 21 girls had known CNS pathology at time of evaluation. Basal LH was significantly higher in girls with newly diagnosed CNS pathology compared to girls with a non-pathological MRI (p = 0.025; no cut of value was found as values overlapped. CONCLUSION: A high frequency of 6-8 year old girls with precocious puberty in our study had a pathological brain MRI, which could not be predicted from any clinical nor biochemical parameters. Thus, we believe that girls with precocious pubertal development of central origin before 8 years of age should continue to be examined by a brain MRI.

  18. Altered small-world efficiency of brain functional networks in acupuncture at ST36: a functional MRI study.

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    Bo Liu

    Full Text Available BACKGROUND: Acupuncture in humans can produce clinical effects via the central nervous system. However, the neural substrates of acupuncture's effects remain largely unknown. RESULTS: We utilized functional MRI to investigate the topological efficiency of brain functional networks in eighteen healthy young adults who were scanned before and after acupuncture at the ST36 acupoints (ACUP and its sham point (SHAM. Whole-brain functional networks were constructed by thresholding temporal correlations matrices of ninety brain regions, followed by a graph theory-based analysis. We showed that brain functional networks exhibited small-world attributes (high local and global efficiency regardless of the order of acupuncture and stimulus points, a finding compatible with previous studies of brain functional networks. Furthermore, the brain networks had increased local efficiency after ACUP stimulation but there were no significant differences after SHAM, indicating a specificity of acupuncture point in coordinating local information flow over the whole brain. Moreover, significant (P<0.05, corrected by false discovery rate approach effects of only acupuncture point were detected on nodal degree of the left hippocampus (higher nodal degree at ACUP as compared to SHAM. Using an uncorrected P<0.05, point-related effects were also observed in the anterior cingulate cortex, frontal and occipital regions while stimulation-related effects in various brain regions of frontal, parietal and occipital cortex regions. In addition, we found that several limbic and subcortical brain regions exhibited point- and stimulation-related alterations in their regional homogeneity (P<0.05, uncorrected. CONCLUSIONS: Our results suggest that acupuncture modulates topological organization of whole-brain functional brain networks and the modulation has point specificity. These findings provide new insights into neuronal mechanism of acupuncture from the perspective of functional

  19. Preliminary evaluation of a brain PET insertable to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Gyuseng [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 South (Korea, Republic of); Choi, Yong [Department of Electronic Engineering, Sogang University, Seoul, 121-742 South (Korea, Republic of); Lee, Jae Sung; An, Hyun Joon [Department of Nuclear Medicine, Seoul National University, Seoul, 110-744 South (Korea, Republic of); Jung, Jin Ho [Department of Electronic Engineering, Sogang University, Seoul, 121-742 South (Korea, Republic of); Park, Hyun Wook; Oh, Chang Hyun; Park, Kyeongjin; Lim, Kyung Taek; Cho, Minsik [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 South (Korea, Republic of); Sul, Woo Suk [National NanoFab Center, Deajeon, 305-806 South (Korea, Republic of); Kim, Hyoungtaek; Kim, Hyunduk [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 South (Korea, Republic of)

    2014-07-29

    There is a new trend of the medical image that diagnoses a brain disease as like Alzheimer dementia. The first qualified candidate is a PET-MRI fusion modality because MRI is a more powerful anatomic diagnosis tool than other modalities. In our study, in order to solve the high magnetic field from MRI, the development was consisted with four main items such as photo-sensor, PET scanner, MRI head-coil and attenuation correction algorithm development.

  20. Association of plasma β-amyloid with MRI markers of structural brain aging the 3-City Dijon study.

    Science.gov (United States)

    Kaffashian, Sara; Tzourio, Christophe; Soumaré, Aïcha; Dufouil, Carole; Mazoyer, Bernard; Schraen-Maschke, Susanna; Buée, Luc; Debette, Stéphanie

    2015-10-01

    Cerebral β-amyloid (Aβ) deposition and atrophy are central features of Alzheimer disease. Studies of Alzheimer disease biomarkers have largely focused on Aβ in cerebrospinal fluid (CSF), and there is uncertainty as to what plasma Aβ may be a marker. We examined the association of Aβ levels in the plasma with magnetic resonance imaging (MRI)-markers of brain aging, including longitudinal changes in global and regional brain volumes, in dementia-free persons. We studied 1530 participants of the Three-City-Dijon cohort, aged 65-80 years. Plasma Aβ measurement and magnetic resonance imaging were performed at baseline and after a 4-year follow up. Total brain, gray matter, and hippocampal volume were estimated using voxel-based morphometry, and annualized change in brain volumes was calculated. Increased plasma Aβ1-40 was associated with lower baseline hippocampal volume. Although baseline plasma Aβ levels were not associated with longitudinal change in brain volumes, consistently high plasma Aβ1-40 levels were associated with faster total brain atrophy and consistently low plasma Aβ1-42/Aβ1-40 ratio, with increased total brain atrophy and gray matter atrophy. In dementia-free older adults, high plasma Aβ1-40 and low plasma Aβ1-42/Aβ1-40 ratio were associated with smaller hippocampal volume and accelerated global and regional brain atrophy respectively.

  1. Atlas-Guided Segmentation of Vervet Monkey Brain MRI

    OpenAIRE

    Li, Xiaoxing; Pohl, Kilian M.; Styner, Martin; Addicott, Merideth; Wyatt, Chris; Daunais, James B.; Fedorov, Andriy; Bouix, Sylvain; Wells, William Mercer; Kikinis, Ron

    2011-01-01

    The vervet monkey is an important nonhuman primate model that allows the study of isolated environmental factors in a controlled environment. Analysis of monkey MRI often suffers from lower quality images compared with human MRI because clinical equipment is typically used to image the smaller monkey brain and higher spatial resolution is required. This, together with the anatomical differences of the monkey brains, complicates the use of neuroimage analysis pipelines tuned for human MRI anal...

  2. Preliminary pilot fMRI study of neuropostural optimization with a noninvasive asymmetric radioelectric brain stimulation protocol in functional dysmetria

    Directory of Open Access Journals (Sweden)

    Mura M

    2012-04-01

    Full Text Available Marco Mura1, Alessandro Castagna2, Vania Fontani2, Salvatore Rinaldi21Institute of Radiology, University of Cagliari, 2Rinaldi Fontani Institute – Department of Neuro Psycho Physical Optimization, Florence, ItalyPurpose: This study assessed changes in functional dysmetria (FD and in brain activation observable by functional magnetic resonance imaging (fMRI during a leg flexion-extension motor task following brain stimulation with a single radioelectric asymmetric conveyer (REAC pulse, according to the precisely defined neuropostural optimization (NPO protocol.Population and methods: Ten healthy volunteers were assessed using fMRI conducted during a simple motor task before and immediately after delivery of a single REAC-NPO pulse. The motor task consisted of a flexion-extension movement of the legs with the knees bent. FD signs and brain activation patterns were compared before and after REAC-NPO.Results: A single 250-millisecond REAC-NPO treatment alleviated FD, as evidenced by patellar asymmetry during a sit-up motion, and modulated activity patterns in the brain, particularly in the cerebellum, during the performance of the motor task.Conclusion: Activity in brain areas involved in motor control and coordination, including the cerebellum, is altered by administration of a REAC-NPO treatment and this effect is accompanied by an alleviation of FD.Keywords: motor behavior, motor control, cerebellum, dysmetria, functional dysmetria, fluctuating asymmetry

  3. Adaptive modulation of adult brain gray and white matter to high altitude: structural MRI studies.

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    Jiaxing Zhang

    Full Text Available The aim of this study was to investigate brain structural alterations in adult immigrants who adapted to high altitude (HA. Voxel-based morphometry analysis of gray matter (GM volumes, surface-based analysis of cortical thickness, and Tract-Based Spatial Statistics analysis of white matter fractional anisotropy (FA based on MRI images were conducted on 16 adults (20-22 years who immigrated to the Qinghai-Tibet Plateau (2300-4400 m for 2 years. They had no chronic mountain sickness. Control group consisted of 16 matched sea level subjects. A battery of neuropsychological tests was also conducted. HA immigrants showed significantly decreased GM volumes in the right postcentral gyrus and right superior frontal gyrus, and increased GM volumes in the right middle frontal gyrus, right parahippocampal gyrus, right inferior and middle temporal gyri, bilateral inferior ventral pons, and right cerebellum crus1. While there was some divergence in the left hemisphere, surface-based patterns of GM changes in the right hemisphere resembled those seen for VBM analysis. FA changes were observed in multiple WM tracts. HA immigrants showed significant impairment in pulmonary function, increase in reaction time, and deficit in mental rotation. Parahippocampal and middle frontal GM volumes correlated with vital capacity. Superior frontal GM volume correlated with mental rotation and postcentral GM correlated with reaction time. Paracentral lobule and frontal FA correlated with mental rotation reaction time. There might be structural modifications occurred in the adult immigrants during adaptation to HA. The changes in GM may be related to impaired respiratory function and psychological deficits.

  4. Halofuginone Inhibits Angiogenesis and Growth in Implanted Metastatic Rat Brain Tumor Model-an MRI Study

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    Rinat Abramovitch

    2004-09-01

    Full Text Available Tumor growth and metastasis depend on angiogenesis; therefore, efforts are made to develop specific angiogenic inhibitors. Halofuginone (HF is a potent inhibitor of collagen type α1(I. In solid tumor models, HF has a potent antitumor and antiangiogenic effect in vivo, but its effect on brain tumors has not yet been evaluated. By employing magnetic resonance imaging (MRI, we monitored the effect of HF on tumor progression and vascularization by utilizing an implanted malignant fibrous histiocytoma metastatic rat brain tumor model. Here we demonstrate that treatment with HF effectively and dose-dependently reduced tumor growth and angiogenesis. On day 13, HF-treated tumors were fivefold smaller than control (P < .001. Treatment with HF significantly prolonged survival of treated animals (142%; P = .001. In HF-treated rats, tumor vascularization was inhibited by 30% on day 13 and by 37% on day 19 (P < .05. Additionally, HF treatment inhibited vessel maturation (P = .03. Finally, in HF-treated rats, we noticed the appearance of a few clusters of satellite tumors, which were distinct from the primary tumor and usually contained vessel cores. This phenomenon was relatively moderate when compared to previous reports of other antiangiogenic agents used to treat brain tumors. We therefore conclude that HF is effective for treatment of metastatic brain tumors.

  5. MRI of perinatal brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Mary; Allsop, Joanna [Imperial College, Robert Steiner MR Unit, Perinatal Imaging, MRC Clinical Sciences Centre, Hammersmith Hospital, London (United Kingdom); Martinez Biarge, Miriam [La Paz University Hospital, Dept of Neonatology, Madrid (Spain); Counsell, Serena [Imperial College, Robert Steiner MR Unit, Neonatal Medicine, MRC Clinical Sciences Centre, Hammersmith Hospital, London (United Kingdom); Cowan, Frances [Imperial College, Dept of Paediatrics, Hammersmith Hospital, London (United Kingdom)

    2010-06-15

    MRI is invaluable in assessing the neonatal brain following suspected perinatal injury. Good quality imaging requires adaptations to both the hardware and the sequences used for adults or older children. The perinatal and postnatal details often predict the pattern of lesions sustained and should be available to aid interpretation of the imaging findings. Perinatal lesions, the pattern of which can predict neurodevelopmental outcome, are at their most obvious on conventional imaging between 1 and 2 weeks from birth. Very early imaging during the first week may be useful to make management decisions in ventilated neonates but brain abnormalities may still be subtle using conventional sequences. Diffusion-weighted imaging (DWI) is very useful for the early identification of ischaemic tissue in the neonatal brain but may underestimate the final extent of injury, particularly basal ganglia and thalamic lesions. MR imaging is an excellent predictor of outcome following perinatal brain injury and can therefore be used as a biomarker in interventional trials designed to reduce injury and improve neurodevelopmental outcome. (orig.)

  6. Effects of methylphenidate on resting-state brain activity in normal adults: an fMRI study

    Institute of Scientific and Technical Information of China (English)

    Yihong Zhu; Bin Gao; Jianming Hua; Weibo Liu; Yichao Deng; Lijie Zhang; Biao Jiang

    2013-01-01

    Methylphenidate (MPH) is one of the most commonly used stimulants for the treatment of attention deficit hyperactivity disorder (ADHD).Although several studies have evaluated the effects of MPH on human brain activation during specific cognitive tasks using functional magnetic resonance imaging (fMRI),few studies have focused on spontaneous brain activity.In the current study,we investigated the effect of MPH on the intra-regional synchronization of spontaneous brain activity during the resting state in 18normal adult males.A handedness questionnaire and the Wechsler Adult Intelligence Scale were applied before medication,and a resting-state fMRI scan was obtained 1 h after medication (20 mg MPH or placebo,order counterbalanced between participants).We demonstrated that:(1) there were no significant differences in the performance of behavioral tasks between the MPH and placebo groups; (2) the left middle and superior temporal gyri had stronger MPH-related regional homogeneity (ReHo); and (3) the left lingual gyrus had weaker MPH-related ReHo.Our findings showed that the ReHo in some brain areas changes with MPH compared to placebo in normal adults,even though there are no behavioral differences.This method can be applied to patients with mental illness who may be treated with MPH,and be used to compare the difference between patients taking MPH and normal participants,to help reveal the mechanism of how MPH works.

  7. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study.

    Science.gov (United States)

    Shi, Yu; Liu, Ziping; Zhang, Shanshan; Li, Qiang; Guo, Shigui; Yang, Jiangming; Wu, Wen

    2015-01-01

    Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP.

  8. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Yu Shi

    2015-01-01

    Full Text Available Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP model and functional magnetic resonance imaging (fMRI to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP and once during tactile stimulation (SHAM pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo values in the pain matrix, limbic system, and default mode network (DMN and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP.

  9. Activated and deactivated functional brain areas in the Deqi state A functional MRI study

    Institute of Scientific and Technical Information of China (English)

    Yong Huang; Tongjun Zeng; Guifeng Zhang; Ganlong Li; Na Lu; Xinsheng Lai; Yangjia Lu; Jiarong Chen

    2012-01-01

    We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state,as reported by physicians and subjects during acupuncture.Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint.Real-time cerebral functional MRI showed that compared with non-sensation after sham needling,true needling activated Brodmann areas 3,6,8,9,10,11,13,20,21,37,39,40,43,and 47,the head of the caudate nucleus,the parahippocampal gyrus,thalamus and red nucleus.True needling also deactivated Brodmann areas 1,2,3,4,5,6,7,9,10,18,24,31,40 and 46.

  10. Single subject pharmacological-MRI (phMRI study: Modulation of brain activity of psoriatic arthritis pain by cyclooxygenase-2 inhibitor

    Directory of Open Access Journals (Sweden)

    Chialvo DR

    2005-11-01

    Full Text Available Abstract We use fMRI to examine brain activity for pain elicited by palpating joints in a single patient suffering from psoriatic arthritis. Changes in these responses are documented when the patient ingested a single dose of a selective cyclooxygenase-2 inhibitor (COX-2i. We show that mechanical stimulation of the painful joints exhibited a cortical activity pattern similar to that reported for acute pain, with activity primarily localized to the thalamus, insular, primary and secondary somatosensory cortices and the mid anterior cingulum. COX-2i resulted in significant decreased in reported pain intensity and in brain activity after 1 hour of administration. The anterior insula and SII correlated with pain intensity, however no central activation site for the drug was detected. We demonstrate the similarity of the activation pattern for palpating painful joints to brain activity in normal subjects in response to thermal painful stimuli, by performing a spatial conjunction analysis between these maps, where overlap is observed in the insula, thalamus, secondary somatosensory cortex, and anterior cingulate. The results demonstrate that one can study effects of pharmacological manipulations in a single subject where the brain activity for a clinical condition is delineated and its modulation by COX-2i demonstrated. This approach may have diagnostic and prognostic utility.

  11. Disease-Specific Regions Outperform Whole-Brain Approaches in Identifying Progressive Supranuclear Palsy: A Multicentric MRI Study

    Science.gov (United States)

    Mueller, Karsten; Jech, Robert; Bonnet, Cecilia; Tintěra, Jaroslav; Hanuška, Jaromir; Möller, Harald E.; Fassbender, Klaus; Ludolph, Albert; Kassubek, Jan; Otto, Markus; Růžička, Evžen; Schroeter, Matthias L.

    2017-01-01

    To identify progressive supranuclear palsy (PSP), we combined voxel-based morphometry (VBM) and support vector machine (SVM) classification using disease-specific features in multicentric magnetic resonance imaging (MRI) data. Structural brain differences were investigated at four centers between 20 patients with PSP and 20 age-matched healthy controls with T1-weighted MRI at 3T. To pave the way for future application in personalized medicine, we applied SVM classification to identify PSP on an individual level besides group analyses based on VBM. We found a major decline in gray matter density in the brainstem, insula, and striatum, and also in frontomedian regions, which is in line with current literature. Moreover, SVM classification yielded high accuracy rates above 80% for disease identification in imaging data. Focusing analyses on disease-specific regions-of-interest (ROI) led to higher accuracy rates compared to a whole-brain approach. Using a polynomial kernel (instead of a linear kernel) led to an increased sensitivity and a higher specificity of disease detection. Our study supports the application of MRI for individual diagnosis of PSP, if combined with SVM approaches. We demonstrate that SVM classification provides high accuracy rates in multicentric data—a prerequisite for potential application in diagnostic routine. PMID:28326008

  12. Structural and functional MRI study of the brain, cognition and mood in long-term adequately treated Hashimoto's thyroiditis.

    Science.gov (United States)

    Quinque, Eva M; Karger, Stefan; Arélin, Katrin; Schroeter, Matthias L; Kratzsch, Jürgen; Villringer, Arno

    2014-04-01

    The current study investigated neuropsychological and underlying structural and functional brain alterations in long-term adequately treated patients with Hashimoto's thyroiditis in order to examine much discussed residual complaints in patients in relation to possible long-term neural alterations with a specific interest in the underlying autoimmune process. Eighteen patients with treated hypothyroidism due to Hashimoto's thyroiditis (mean age 32, range 18-54 years; two males; mean treatment duration 4.4 years) and 18 healthy matched control subjects underwent 3-Tesla magnetic resonance imaging (MRI). Voxel-based morphometry was used to investigate grey matter density, resting-state functional MRI to analyse the brain connectivity of areas known to be altered in hypothyroidism and event-related functional MRI to examine brain activity during associative memory encoding. Neuropsychological assessment included memory, working memory, psychomotor speed and attention. We previously reported subclinically reduced mood in this study population and investigated its neural correlates here. Thyroid stimulating hormone, free triiodthyronine, free thyroxine and thyroid peroxidase antibodies were measured in serum. We did not find cognitive deficits or alterations in grey matter density, functional connectivity or associative memory-related brain activity in comparison to the control group and cognition was unrelated to thyroid serum measures in the patient group. Thyroid peroxidase antibodies in the patient group correlated with increased grey matter density in right amygdala and enhanced connectivity between subcallosal and parahippocampal areas. Treatment duration was associated with brain structure in frontal and occipital cortex and connectivity between left amygdala and frontal cortex. Mood correlated with brain areas associated with distinct functional networks, but not with those most prominently affected in depression. In conclusion, no cognitive or neural

  13. [Standartization of MRI studies in multiple sclerosis].

    Science.gov (United States)

    Bryukhov, V V; Krotenkova, I A; Morozova, S N; Krotenkova, M V

    2016-01-01

    The use of magnetic resonance imaging (MRI) in patients with multiple sclerosis has markedly increased in recent years. The main task of the MRI studies after the diagnosis of multiple sclerosis is to assess the dynamics of MRI for determining disease progression and monitoring the efficacy of therapy. In this regard, it is very important to obtain the most identical baseline and follow-up MRI that is possible when a single standard protocol is used. This article presents the protocol of brain MRI and spinal cord MRI and interpretation of MRI studies in patients with multiple sclerosis.

  14. Automatic Analysis of Brain Tissue and Structural Connectivity in MRI

    NARCIS (Netherlands)

    R. de Boer (Renske)

    2011-01-01

    textabstractStudies of the brain using magnetic resonance imaging (MRI) can provide insights in physiology and pathology that can eventually aid clinical diagnosis and therapy monitoring. MRI data acquired in these studies can be difficult, as well as laborious, to interpret and analyze by human obs

  15. Digital atlas of fetal brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Teresa; Weinberger, E. [Department of Radiology, Seattle Children' s Hospital, Seattle, WA (United States); Matesan, Manuela [University of Washington, Department of Radiology, Seattle, WA (United States); Bulas, Dorothy I. [Division of Diagnostic Imaging and Radiology, Children' s National Medical Center, Washington, DC (United States)

    2010-02-15

    Fetal MRI can be performed in the second and third trimesters. During this time, the fetal brain undergoes profound structural changes. Interpretation of appropriate development might require comparison with normal age-based models. Consultation of a hard-copy atlas is limited by the inability to compare multiple ages simultaneously. To provide images of normal fetal brains from weeks 18 through 37 in a digital format that can be reviewed interactively. This will facilitate recognition of abnormal brain development. T2-W images for the atlas were obtained from fetal MR studies of normal brains scanned for other indications from 2005 to 2007. Images were oriented in standard axial, coronal and sagittal projections, with laterality established by situs. Gestational age was determined by last menstrual period, earliest US measurements and sonogram performed on the same day as the MR. The software program used for viewing the atlas, written in C, permits linked scrolling and resizing the images. Simultaneous comparison of varying gestational ages is permissible. Fetal brain images across gestational ages 18 to 37 weeks are provided as an interactive digital atlas and are available for free download. Improved interpretation of fetal brain abnormalities can be facilitated by the use of digital atlas cataloging of the normal changes throughout fetal development. Here we provide a description of the atlas and a discussion of normal fetal brain development. (orig.)

  16. A Review of Brain Extraction Techniques in Fetal MRI

    Directory of Open Access Journals (Sweden)

    Morteza Pishghadam

    2016-03-01

    Full Text Available Sonography, Maternal Serum Screening, amniocentesis, and sampling are among the techniques utilized to examine a developing fetus and diagnose fetal abnormalities in the uterus. Despite the fact that Sonography is the main technique used for imaging and monitoring, the use of Magnetic Resonance Imaging (MRI to evaluate the fetus is growing. Moreover, MRI is used for further examinations in case of abnormalities diagnosed in the ultrasound scan. MRI, in comparison with other imaging techniques, provides the advantage of fetal brain study with higher precision and quality. The first step to study the fetal brain is its extraction from the MRI of the fetal brain. Since the maternal tissue is also present in the MRI of the fetal brain tissue, and due to the differences in the adult and fetus signals of brain tissue, it is not possible to use the adult brain extraction techniques for fetus. Given that semi-automatic segmentation is a time-consuming and tedious task, the need for automatic segmentation is highlighted. This is while the development of the stages of automatic segmentation of brain structures is still a challenge to overcome. In the present paper, we review the techniques for automatic segmentation or brain extraction of fetal MRI.

  17. Food and drug cues activate similar brain regions: a meta-analysis of functional MRI studies.

    Science.gov (United States)

    Tang, D W; Fellows, L K; Small, D M; Dagher, A

    2012-06-06

    In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards.

  18. Brain responses to altered auditory feedback during musical keyboard production: an fMRI study.

    Science.gov (United States)

    Pfordresher, Peter Q; Mantell, James T; Brown, Steven; Zivadinov, Robert; Cox, Jennifer L

    2014-03-27

    Alterations of auditory feedback during piano performance can be profoundly disruptive. Furthermore, different alterations can yield different types of disruptive effects. Whereas alterations of feedback synchrony disrupt performed timing, alterations of feedback pitch contents can disrupt accuracy. The current research tested whether these behavioral dissociations correlate with differences in brain activity. Twenty pianists performed simple piano keyboard melodies while being scanned in a 3-T magnetic resonance imaging (MRI) scanner. In different conditions they experienced normal auditory feedback, altered auditory feedback (asynchronous delays or altered pitches), or control conditions that excluded movement or sound. Behavioral results replicated past findings. Neuroimaging data suggested that asynchronous delays led to increased activity in Broca's area and its right homologue, whereas disruptive alterations of pitch elevated activations in the cerebellum, area Spt, inferior parietal lobule, and the anterior cingulate cortex. Both disruptive conditions increased activations in the supplementary motor area. These results provide the first evidence of neural responses associated with perception/action mismatch during keyboard production.

  19. Measurement of blood-brain barrier permeability with t1-weighted dynamic contrast-enhanced MRI in brain tumors: a comparative study with two different algorithms.

    Science.gov (United States)

    Bergamino, Maurizio; Saitta, Laura; Barletta, Laura; Bonzano, Laura; Mancardi, Giovanni Luigi; Castellan, Lucio; Ravetti, Jean Louis; Roccatagliata, Luca

    2013-01-01

    The purpose of this study was to assess the feasibility of measuring different permeability parameters with T1-weighted dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in order to investigate the blood brain-barrier permeability associated with different brain tumors. The Patlak algorithm and the extended Tofts-Kety model were used to this aim. Twenty-five adult patients with tumors of different histological grades were enrolled in this study. MRI examinations were performed at 1.5 T. Multiflip angle, fast low-angle shot, and axial 3D T1-weighted images were acquired to calculate T1 maps, followed by a DCE acquisition. A region of interest was placed within the tumor of each patient to calculate the mean value of different permeability parameters. Differences in permeability measurements were found between different tumor grades, with higher histological grades characterized by higher permeability values. A significant difference in transfer constant (K (trans)) values was found between the two methods on high-grade tumors; however, both techniques revealed a significant correlation between the histological grade of tumors and their K (trans) values. Our results suggest that DCE acquisition is feasible in patients with brain tumors and that K (trans) maps can be easily obtained by these two algorithms, even if the theoretical model adopted could affect the final results.

  20. Corpus callosum thickness on mid-sagittal MRI as a marker of brain volume: a pilot study in children with HIV-related brain disease and controls

    Energy Technology Data Exchange (ETDEWEB)

    Andronikou, Savvas [University of the Witwatersrand, Department of Radiology, Faculty of Health Sciences, Cape Town (South Africa); Ackermann, Christelle [University of Stellenbosch, Department of Radiology, Stellenbosch (South Africa); Laughton, Barbara; Cotton, Mark [Stellenbosch University and Tygerberg Children' s Hospital, Children' s Infectious Diseases Research Unit, Stellenbosch (South Africa); Tomazos, Nicollette [University of Cape Town, Faculty of Commerce, Department of Management Studies, Cape Town (South Africa); Spottiswoode, Bruce [University of Cape Town, MRC/UCT Medical Imaging Research Unit, Department of Human Biology, Cape Town (South Africa); Mauff, Katya [University of Cape Town, Department of Statistical Sciences, Cape Town (South Africa); Pettifor, John M. [University of the Witwatersrand, MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, Witwatersrand (South Africa)

    2015-07-15

    Corpus callosum thickness measurement on mid-sagittal MRI may be a surrogate marker of brain volume. This is important for evaluation of diseases causing brain volume gain or loss, such as HIV-related brain disease and HIV encephalopathy. To determine if thickness of the corpus callosum on mid-sagittal MRI is a surrogate marker of brain volume in children with HIV-related brain disease and in controls without HIV. A retrospective MRI analysis in children (<5 years old) with HIV-related brain disease and controls used a custom-developed semi-automated tool, which divided the midline corpus callosum and measured its thickness in multiple locations. Brain volume was determined using volumetric analysis. Overall corpus callosum thickness and thickness of segments of the corpus callosum were correlated with overall and segmented (grey and white matter) brain volume. Forty-four children (33 HIV-infected patients and 11 controls) were included. Significant correlations included overall corpus callosum (mean) and total brain volume (P = 0.05); prefrontal corpus callosum maximum with white matter volume (P = 0.02); premotor corpus callosum mean with total brain volume (P = 0.04) and white matter volume (P = 0.02), premotor corpus callosum maximum with white matter volume (P = 0.02) and sensory corpus callosum mean with total brain volume (P = 0.02). Corpus callosum thickness correlates with brain volume both in HIV-infected patients and controls. (orig.)

  1. Amplitude of Sensorimotor Mu Rhythm Is Correlated with BOLD from Multiple Brain Regions: A Simultaneous EEG-fMRI Study

    Science.gov (United States)

    Yin, Siyang; Liu, Yuelu; Ding, Mingzhou

    2016-01-01

    The mu rhythm is a field oscillation in the ∼10Hz range over the sensorimotor cortex. For decades, the suppression of mu (event-related desynchronization) has been used to index movement planning, execution, and imagery. Recent work reports that non-motor processes, such as spatial attention and movement observation, also desynchronize mu, raising the possibility that the mu rhythm is associated with the activity of multiple brain regions and systems. In this study, we tested this hypothesis by recording simultaneous resting-state EEG-fMRI from healthy subjects. Independent component analysis (ICA) was applied to extract the mu components. The amplitude (power) fluctuations of mu were estimated as a time series using a moving-window approach, which, after convolving with a canonical hemodynamic response function (HRF), was correlated with blood-oxygen-level-dependent (BOLD) signals from the entire brain. Two main results were found. First, mu power was negatively correlated with BOLD from areas of the sensorimotor network, the attention control network, the putative mirror neuron system, and the network thought to support theory of mind. Second, mu power was positively correlated with BOLD from areas of the salience network, including anterior cingulate cortex and anterior insula. These results are consistent with the hypothesis that sensorimotor mu rhythm is associated with multiple brain regions and systems. They also suggest that caution should be exercised when attempting to interpret mu modulation in terms of a single brain network. PMID:27499736

  2. Branding and a child's brain: an fMRI study of neural responses to logos.

    Science.gov (United States)

    Bruce, Amanda S; Bruce, Jared M; Black, William R; Lepping, Rebecca J; Henry, Janice M; Cherry, Joseph Bradley C; Martin, Laura E; Papa, Vlad B; Davis, Ann M; Brooks, William M; Savage, Cary R

    2014-01-01

    Branding and advertising have a powerful effect on both familiarity and preference for products, yet no neuroimaging studies have examined neural response to logos in children. Food advertising is particularly pervasive and effective in manipulating choices in children. The purpose of this study was to examine how healthy children's brains respond to common food and other logos. A pilot validation study was first conducted with 32 children to select the most culturally familiar logos, and to match food and non-food logos on valence and intensity. A new sample of 17 healthy weight children were then scanned using functional magnetic resonance imaging. Food logos compared to baseline were associated with increased activation in orbitofrontal cortex and inferior prefrontal cortex. Compared to non-food logos, food logos elicited increased activation in posterior cingulate cortex. Results confirmed that food logos activate some brain regions in children known to be associated with motivation. This marks the first study in children to examine brain responses to culturally familiar logos. Considering the pervasiveness of advertising, research should further investigate how children respond at the neural level to marketing.

  3. [MRI compatibility of deep brain stimulator].

    Science.gov (United States)

    Zhang, Yujing

    2013-07-01

    Deep brain stimulation (DBS) therapy develops rapidly in clinical application. The structures of deep brain stimulator and magnetic resonance imaging (MRI) equipment are introduced, the interactions are analyzed, and the two compatible problems of radio frequency (RF) heating and imaging artifact are summarized in this paper.

  4. Language exposure induced neuroplasticity in the bilingual brain: a follow-up fMRI study.

    Science.gov (United States)

    Tu, Liu; Wang, Junjing; Abutalebi, Jubin; Jiang, Bo; Pan, Ximin; Li, Meng; Gao, Wei; Yang, Yuchen; Liang, Bishan; Lu, Zhi; Huang, Ruiwang

    2015-03-01

    Although several studies have shown that language exposure crucially influence the cerebral representation of bilinguals, the effects of short-term change of language exposure in daily life upon language control areas in bilinguals are less known. To explore this issue, we employed follow-up fMRI to investigate whether differential exposure induces neuroplastic changes in the language control network in high-proficient Cantonese (L1)-Mandarin (L2) early bilinguals. The same 10 subjects underwent twice BOLD-fMRI scans while performing a silent narration task which corresponded to two different language exposure conditions, CON-1 (L1/L2 usage percentage, 50%:50%) and CON-2 (L1/L2 usage percentage, 90%:10%). We report a strong effect of language exposure in areas related to language control for the less exposed language. Interestingly, these significant effects were present after only a 30-day period of differential language exposure. In detail, we reached the following results: (1) the interaction effect of language and language exposure condition was found significantly in the left pars opercularis (BA 44) and marginally in the left MFG (BA 9); (2) in CON-2, increases of activation values in L2 were found significantly in bilateral BA 46 and BA 9, in the left BA44, and marginally in the left caudate; and (3) in CON-2, we found a significant negative correlation between language exposure to L2 and the BOLD activation value specifically in the left ACC. These findings strongly support the hypothesis that even short periods of differential exposure to a given language may induce significant neuroplastic changes in areas responsible for language control. The language which a bilingual is less exposed to and is also less used will be in need of increased mental control as shown by the increased activity of language control areas.

  5. Applications of arterial spin labeled MRI in the brain.

    Science.gov (United States)

    Detre, John A; Rao, Hengyi; Wang, Danny J J; Chen, Yu Fen; Wang, Ze

    2012-05-01

    Perfusion provides oxygen and nutrients to tissues and is closely tied to tissue function while disorders of perfusion are major sources of medical morbidity and mortality. It has been almost two decades since the use of arterial spin labeling (ASL) for noninvasive perfusion imaging was first reported. While initial ASL magnetic resonance imaging (MRI) studies focused primarily on technological development and validation, a number of robust ASL implementations have emerged, and ASL MRI is now also available commercially on several platforms. As a result, basic science and clinical applications of ASL MRI have begun to proliferate. Although ASL MRI can be carried out in any organ, most studies to date have focused on the brain. This review covers selected research and clinical applications of ASL MRI in the brain to illustrate its potential in both neuroscience research and clinical care.

  6. Ultra-high magnetic resonance imaging (MRI): a potential examination for deep brain stimulation devices and the limitation study concerning MRI-related heating injury.

    Science.gov (United States)

    Chen, Ying-Chuan; Li, Jun-Ju; Zhu, Guan-Yu; Shi, Lin; Yang, An-Chao; Jiang, Yin; Zhang, Xin; Zhang, Jian-Guo

    2017-03-01

    Nowadays, the patients with deep brain stimulation (DBS) devices are restricted to undertake 1.5T magnetic resonance imaging (MRI) according to the guideline. Nevertheless, we conducted an experiment to test pathological change near the leads in different field-strength MRI. Twenty-four male New Zealand rabbits were assigned to Group 1 (G1, n = 6, 7.0T, DBS), Group 2 (G2, n = 6, 3.0T, DBS), Group 3 (G3, n = 6, 1.5T, DBS), and Group 4 (G4, n = 6, 1.5T, paracentesis). DBS leads were implanted in G1, G2 and G3, targeting left nucleus ventralis posterior thalami. Paracentesis was performed in G4. 24 h after MRI scan, all animals were killed for examining pathological alternation (at different distance from lead) via transmission electron microscopy. Our results suggest that the severity of tissue injury correlates with the distance to electrode instead of field strength of MRI. Up to now, the reason for the restriction of MRI indicated no significantly different pathological change.

  7. Surface-Based fMRI-Driven Diffusion Tractography in the Presence of Significant Brain Pathology: A Study Linking Structure and Function in Cerebral Palsy

    Science.gov (United States)

    Cunnington, Ross; Boyd, Roslyn N.; Rose, Stephen E.

    2016-01-01

    Diffusion MRI (dMRI) tractography analyses are difficult to perform in the presence of brain pathology. Automated methods that rely on cortical parcellation for structural connectivity studies often fail, while manually defining regions is extremely time consuming and can introduce human error. Both methods also make assumptions about structure-function relationships that may not hold after cortical reorganisation. Seeding tractography with functional-MRI (fMRI) activation is an emerging method that reduces these confounds, but inherent smoothing of fMRI signal may result in the inclusion of irrelevant pathways. This paper describes a novel fMRI-seeded dMRI-analysis pipeline based on surface-meshes that reduces these issues and utilises machine-learning to generate task specific white matter pathways, minimising the requirement for manually-drawn ROIs. We directly compared this new strategy to a standard voxelwise fMRI-dMRI approach, by investigating correlations between clinical scores and dMRI metrics of thalamocortical and corticomotor tracts in 31 children with unilateral cerebral palsy. The surface-based approach successfully processed more participants (87%) than the voxel-based approach (65%), and provided significantly more-coherent tractography. Significant correlations between dMRI metrics and five clinical scores of function were found for the more superior regions of these tracts. These significant correlations were stronger and more frequently found with the surface-based method (15/20 investigated were significant; R2 = 0.43–0.73) than the voxelwise analysis (2 sig. correlations; 0.38 & 0.49). More restricted fMRI signal, better-constrained tractography, and the novel track-classification method all appeared to contribute toward these differences. PMID:27487011

  8. Prediction of individual brain maturity using fMRI.

    Science.gov (United States)

    Dosenbach, Nico U F; Nardos, Binyam; Cohen, Alexander L; Fair, Damien A; Power, Jonathan D; Church, Jessica A; Nelson, Steven M; Wig, Gagan S; Vogel, Alecia C; Lessov-Schlaggar, Christina N; Barnes, Kelly Anne; Dubis, Joseph W; Feczko, Eric; Coalson, Rebecca S; Pruett, John R; Barch, Deanna M; Petersen, Steven E; Schlaggar, Bradley L

    2010-09-10

    Group functional connectivity magnetic resonance imaging (fcMRI) studies have documented reliable changes in human functional brain maturity over development. Here we show that support vector machine-based multivariate pattern analysis extracts sufficient information from fcMRI data to make accurate predictions about individuals' brain maturity across development. The use of only 5 minutes of resting-state fcMRI data from 238 scans of typically developing volunteers (ages 7 to 30 years) allowed prediction of individual brain maturity as a functional connectivity maturation index. The resultant functional maturation curve accounted for 55% of the sample variance and followed a nonlinear asymptotic growth curve shape. The greatest relative contribution to predicting individual brain maturity was made by the weakening of short-range functional connections between the adult brain's major functional networks.

  9. Cognition and brain abnormalities on MRI in pituitary patients

    Energy Technology Data Exchange (ETDEWEB)

    Brummelman, Pauline [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Sattler, Margriet G.A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen (Netherlands); Department of Radiation Oncology, Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Amsterdam (Netherlands); Meiners, Linda C. [Department of Radiology, University of Groningen, University Medical Center Groningen (Netherlands); Berg, Gerrit van den; Klauw, Melanie M. van der [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Elderson, Martin F. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); LifeLines Cohort Study and Biobank, University of Groningen, University Medical Center Groningen (Netherlands); Dullaart, Robin P.F. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Koerts, Janneke [Department of Clinical and Developmental Neuropsychology, University of Groningen, Groningen (Netherlands); Werumeus Buning, Jorien, E-mail: j.werumeus.buning@umcg.nl [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); Tucha, Oliver [Department of Clinical and Developmental Neuropsychology, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands); LifeLines Cohort Study and Biobank, University of Groningen, University Medical Center Groningen (Netherlands); Bergh, Alfons C.M. van den [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen (Netherlands); Beek, André P. van, E-mail: a.p.van.beek@umcg.nl [Department of Endocrinology, University of Groningen, University Medical Center Groningen (Netherlands)

    2015-02-15

    Highlights: • Cognitive impairments are frequently observed in treated NFA patients. • NFA patients with cognitive impairments do not show brain abnormalities on MRI more frequently than patients without cognitive impairments. • The absence of brain abnormalities on brain MRI does not exclude impairments of cognition. - Abstract: Purpose: The extent to which cognitive dysfunction is related to specific brain abnormalities in patients treated for pituitary macroadenoma is unclear. Therefore, we compared brain abnormalities seen on Magnetic Resonance Imaging (MRI) in patients treated for nonfunctioning pituitary macroadenoma (NFA) with or without impairments in cognitive functioning. Methods: In this cross-sectional design, a cohort of 43 NFA patients was studied at the University Medical Center Groningen. White matter lesions (WMLs), cerebral atrophy, (silent) brain infarcts and abnormalities of the temporal lobes and hippocampi were assessed on pre-treatment and post-treatment MRI scans. Post-treatment cognitive examinations were performed using a verbal memory and executive functioning test. We compared our patient cohort with large reference populations representative of the Dutch population. Results: One or more impairments on both cognitive tests were frequently observed in treated NFA patients. No treatment effects were found with regard to the comparison between patients with and without impairments in executive functioning. Interestingly, in patients with one or more impairments on verbal memory function, treatment with radiotherapy had been given more frequently (74% in the impaired group versus 40% in the unimpaired group, P = 0.025). Patients with or without any brain abnormality on MRI did not differ in verbal memory or executive functioning. Conclusions: Brain abnormalities on MRI are not observed more frequently in treated NFA patients with impairments compared to NFA patients without impairments in verbal memory or executive functioning

  10. MRI and MRS of human brain tumors.

    Science.gov (United States)

    Hou, Bob L; Hu, Jiani

    2009-01-01

    The purpose of this chapter is to provide an introduction to magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of human brain tumors, including the primary applications and basic terminology involved. Readers who wish to know more about this broad subject should seek out the referenced books (1. Tofts (2003) Quantitative MRI of the brain. Measuring changes caused by disease. Wiley; Bradley and Stark (1999) 2. Magnetic resonance imaging, 3rd Edition. Mosby Inc; Brown and Semelka (2003) 3. MRI basic principles and applications, 3rd Edition. Wiley-Liss) or reviews (4. Top Magn Reson Imaging 17:127-36, 2006; 5. JMRI 24:709-724, 2006; 6. Am J Neuroradiol 27:1404-1411, 2006).MRI is the most popular means of diagnosing human brain tumors. The inherent difference in the magnetic resonance (MR) properties of water between normal tissues and tumors results in contrast differences on the image that provide the basis for distinguishing tumors from normal tissues. In contrast to MRI, which provides spatial maps or images using water signals of the tissues, proton MRS detects signals of tissue metabolites. MRS can complement MRI because the observed MRS peaks can be linked to inherent differences in biochemical profiles between normal tissues and tumors.The goal of MRI and MRS is to characterize brain tumors, including tumor core, edge, edema, volume, types, and grade. The commonly used brain tumor MRI protocol includes T2-weighted images and T1-weighted images taken both before and after the injection of a contrast agent (typically gadolinium: Gd). The commonly used MRS technique is either point-resolved spectroscopy (PRESS) or stimulated echo acquisition mode (STEAM).

  11. In vivo brain anatomy of adult males with Fragile X syndrome: an MRI study.

    LENUS (Irish Health Repository)

    Hallahan, Brian P

    2011-01-01

    Fragile X Syndrome (FraX) is caused by the expansion of a single trinucleotide gene sequence (CGG) on the X chromosome, and is a leading cause of learning disability (mental retardation) worldwide. Relatively few studies, however, have examined the neuroanatomical abnormalities associated with FraX. Of those that are available many included mixed gender populations, combined FraX children and adults into one sample, and employed manual tracing techniques which measures bulk volume of particular regions. Hence, there is relatively little information on differences in grey and white matter content across whole brain. We employed magnetic resonance imaging to investigate brain anatomy in 17 adult males with FraX and 18 healthy controls that did not differ significantly in age. Data were analysed using stereology and VBM to compare (respectively) regional brain bulk volume, and localised grey\\/white matter content. Using stereology we found that FraX males had a significant increase in bulk volume bilaterally of the caudate nucleus and parietal lobes and of the right brainstem, but a significant decrease in volume of the left frontal lobe. Our complimentary VBM analysis revealed an increased volume of grey matter in fronto-striatal regions (including bilaterally in the caudate nucleus), and increased white matter in regions extending from the brainstem to the parahippocampal gyrus, and from the left cingulate cortex extending into the corpus callosum. People with FraX have regionally specific differences in brain anatomy from healthy controls with enlargement of the caudate nuclei that persists into adulthood.

  12. Brain-Gut Axis Modulation of Acupuncture in Functional Dyspepsia: A Preliminary Resting-State fcMRI Study

    Directory of Open Access Journals (Sweden)

    Jiliang Fang

    2015-01-01

    Full Text Available Objective. To explore acupuncture effects on brain functional connectivity in patients with functional dyspepsia (FD. Methods. Eight patients in an acupuncture treatment group and ten healthy adults in the control group participated in the study. Acupuncture effectiveness was evaluated based on changes of the gastrointestinal symptoms, gastric motility measurements, and gastrin levels and comparisons with the control group when appropriate. To investigate functional connectivity changes related to FD and potential modulation after acupuncture, a set of regions of interest (ROIs were selected according to previous fMRI reports of acupuncture. Results. Patients showed significant improvements of FD signs and symptoms after acupuncture treatments. For all of the ROIs, we identified subportions of the networks showing reduced connectivity in patients with FD. Connectivity between the ROIs and corresponding disease targets showed significant improvement after acupuncture treatment (P<0.05 in all ROIs except for right medial temporal lobe-hippocampus and right inferior parietal lobule. Conclusion. Functional connectivity of the brain is changed in patients with FD but approximates that in healthy control after acupuncture treatment. The relief of gastrointestinal signs and symptoms by acupuncture is likely due to the normalization of brain-gut axis associated with FD.

  13. The Effects of Acupuncture Stimulation for Brain Activation and Alcohol Abstinence Self-Efficacy: Functional MRI Study

    Science.gov (United States)

    Choi, Seong Hun; Kim, Ju Sang; Ryu, Yeon Hee; Lim, Young Jin; Kim, Moon Seup; Sohn, Jeong woo; Oh, Sung Suk

    2017-01-01

    We attempted to investigate whether acupuncture stimulation at HT7 can have an effect on brain activation patterns and alcohol abstinence self-efficacy. Thirty-four right-handed healthy subjects were recruited for this study. They were randomly assigned into two groups: the HT7 (Shenmen) group and the LI5 (Yangxi) group. Acupuncture stimulation was performed using a block paradigm during fMRI scanning. Additionally, the Korean version of Alcohol Abstinence Self-Efficacy Scale (AASES) was used to determine the effect of acupuncture stimulation on self-efficacy to abstain from alcohol use. According to the result of fMRI group analysis, the activation induced by HT7 stimulation was found on the bilateral postcentral gyrus, inferior parietal lobule, inferior frontal gyrus, claustrum, insula, and anterior lobe of the cerebellum, as well as on the left posterior lobe of the cerebellum (p < 0.001, uncorrected). According to the AASES analysis, the interaction effect for gender and treatment was marginally significant (F(1, 30) = 4.152, p = 0.050). For female group, the simple main effect of treatment was significant (F(1, 11) = 8.040, p = 0.016), indicating that the mean change score was higher in the HT7 stimulation than in the LI5 stimulation. Therefore, our study has provided evidence to support that HT7 stimulation has a positive therapeutic effect on the alcohol-related diseases. PMID:28280514

  14. The Effects of Acupuncture Stimulation for Brain Activation and Alcohol Abstinence Self-Efficacy: Functional MRI Study

    Directory of Open Access Journals (Sweden)

    Chae Ha Yang

    2017-01-01

    Full Text Available We attempted to investigate whether acupuncture stimulation at HT7 can have an effect on brain activation patterns and alcohol abstinence self-efficacy. Thirty-four right-handed healthy subjects were recruited for this study. They were randomly assigned into two groups: the HT7 (Shenmen group and the LI5 (Yangxi group. Acupuncture stimulation was performed using a block paradigm during fMRI scanning. Additionally, the Korean version of Alcohol Abstinence Self-Efficacy Scale (AASES was used to determine the effect of acupuncture stimulation on self-efficacy to abstain from alcohol use. According to the result of fMRI group analysis, the activation induced by HT7 stimulation was found on the bilateral postcentral gyrus, inferior parietal lobule, inferior frontal gyrus, claustrum, insula, and anterior lobe of the cerebellum, as well as on the left posterior lobe of the cerebellum (p<0.001, uncorrected. According to the AASES analysis, the interaction effect for gender and treatment was marginally significant (F(1,30=4.152, p=0.050. For female group, the simple main effect of treatment was significant (F(1,11=8.040, p=0.016, indicating that the mean change score was higher in the HT7 stimulation than in the LI5 stimulation. Therefore, our study has provided evidence to support that HT7 stimulation has a positive therapeutic effect on the alcohol-related diseases.

  15. Abnormal baseline brain activity in patients with neuromyelitis optica: A resting-state fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yaou [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Liang Peipeng [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); International WIC institute, Beijing University of Technology, Beijing 100024 (China); Duan Yunyun; Jia Xiuqin; Wang Fei; Yu Chunshui; Qin Wen [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong Huiqing; Ye Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Li Kuncheng, E-mail: likuncheng1955@yahoo.com.cn [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

    2011-11-15

    Purpose: Recent immunopathologic and MRI findings suggest that tissue damage in neuromyelitis optica (NMO) is not limited to spinal cord and optic nerve, but also in brain. Baseline brain activity can reveal the brain functional changes to the tissue damages and give clues to the pathophysiology of NMO, however, it has never been explored by resting-state functional MRI (fMRI). We used regional amplitude of low frequency fluctuation (ALFF) as an index in resting-state fMRI to investigate how baseline brain activity changes in patients with NMO. Methods: Resting-state fMRIs collected from seventeen NMO patients and seventeen age- and sex-matched normal controls were compared to investigate the ALFF difference between the two groups. The relationships between ALFF in regions with significant group differences and the EDSS (Expanded Disability Status Scale), disease duration were further explored. Results: Our results showed that NMO patients had significantly decreased ALFF in precuneus, posterior cingulate cortex (PCC) and lingual gyrus; and increased ALFF in middle frontal gyrus, caudate nucleus and thalamus, compared to normal controls. Moderate negative correlations were found between the EDSS and ALFF in the left middle frontal gyrus (r = -0.436, p = 0.040) and the left caudate (r = -0.542, p = 0.012). Conclusion: The abnormal baseline brain activity shown by resting-state fMRI in NMO is relevant to cognition, visual and motor systems. It implicates a complex baseline brain status of both functional impairments and adaptations caused by tissue damages in these systems, which gives clues to the pathophysiology of NMO.

  16. Brain activation in discourse comprehension: a 3t fMRI study.

    Science.gov (United States)

    Martín-Loeches, Manuel; Casado, Pilar; Hernández-Tamames, Juan A; Alvarez-Linera, Juan

    2008-06-01

    To date a very small number of functional neuroimaging studies have specifically examined the effects of story coherence on brain activation using long narratives, a procedure fundamental to the study of global coherence. These studies, however, not only yielded notably divergent results, but also featured a number of caveats. It is the purpose of the present study to try to overcome some of these limitations. A left precuneus/posterior cingulate activation related to global coherence comprehension was in consonance with a part of previous literature. However, our most important results corresponded to left parietal regions (angular gyrus, BA 39), this diverging from the previous studies. Recent developments of the situational models of narrative comprehension could explain all these apparently inconsistent results. According to these, different situation models would be created as a function of the content of the narratives, which would yield in turn different patterns of brain activity. Our data also suggest that the same content might also give place to different situation models as a function of the degree of global coherence achieved by the reader or listener.

  17. A brief report on MRI investigation of experimental traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Timothy Q.Duong; Lora T.Watts

    2016-01-01

    Traumatic brain injury is a major cause of death and disability. This is a brief report based on a symposium presentation to the2014 Chinese Neurotrauma Association Meeting in San Francisco, USA. It covers the work from our laboratory in applying multimodal MRI to study experimental traumatic brain injury in rats with comparisons made to behavioral tests and histology. MRI protocols include structural, perfusion, manganese-enhanced, diffusion-tensor MRI, and MRI of blood-brain barrier integrity and cerebrovascular reactivity.

  18. A study of the brain's resting state based on alpha band power, heart rate and fMRI

    NARCIS (Netherlands)

    de Munck, J.C.; Goncalves, S.I.; Faes, T.J.C.; Kuijer, J.P.A.; Pouwels, P.J.W.; Heethaar, R.M.; Lopes da Silva, F.H.

    2008-01-01

    Considering that there are several theoretical reasons why fMRI data is correlated to variations in heart rate, these correlations are explored using experimental resting state data. In particular, the possibility is discussed that the "default network", being a brain area that deactivates during no

  19. MRI Brain Tumor Segmentation Methods- A Review

    OpenAIRE

    Gursangeet, Kaur; Jyoti, Rani

    2016-01-01

    Medical image processing and its segmentation is an active and interesting area for  researchers. It has reached at the tremendous place in diagnosing tumors after the discovery of CT and MRI. MRI is an useful tool to detect the brain tumor and segmentation is performed to carry out the useful portion from an image. The purpose of this paper is to provide an overview of different image segmentation methods like watershed algorithm, morphological operations, neutrosophic sets, thresholding, K-...

  20. Brain intra- and extracellular sodium concentration in multiple sclerosis: a 7 T MRI study.

    Science.gov (United States)

    Petracca, Maria; Vancea, Roxana O; Fleysher, Lazar; Jonkman, Laura E; Oesingmann, Niels; Inglese, Matilde

    2016-03-01

    Intra-axonal accumulation of sodium ions is one of the key mechanisms of delayed neuro-axonal degeneration that contributes to disability accrual in multiple sclerosis. In vivo sodium magnetic resonance imaging studies have demonstrated an increase of brain total sodium concentration in patients with multiple sclerosis, especially in patients with greater disability. However, total sodium concentration is a weighted average of intra- and extra-cellular sodium concentration whose changes reflect different tissue pathophysiological processes. The in vivo, non-invasive measurement of intracellular sodium concentration is quite challenging and the few applications in patients with neurological diseases are limited to case reports and qualitative assessments. In the present study we provide first evidence of the feasibility of triple quantum filtered (23)Na magnetic resonance imaging at 7 T, and provide in vivo quantification of global and regional brain intra- and extra-cellular sodium concentration in 19 relapsing-remitting multiple sclerosis patients and 17 heathy controls. Global grey matter and white matter total sodium concentration (respectively P brain regional level, clusters of increased total sodium concentration and intracellular sodium concentration and decreased intracellular sodium volume fraction were found in several cortical, subcortical and white matter regions when patients were compared with healthy controls (P < 0.05 family-wise error corrected for total sodium concentration, P < 0.05 uncorrected for multiple comparisons for intracellular sodium concentration and intracellular sodium volume fraction). Measures of total sodium concentration and intracellular sodium volume fraction, but not measures of intracellular sodium concentration were correlated with T2-weighted and T1-weighted lesion volumes (0.05 < P < 0.01) and with Expanded Disability Status Scale (P < 0.05). Thus, suggesting that while intracellular sodium volume fraction decrease could

  1. Urea cycle disorders: brain MRI and neurological outcome

    Energy Technology Data Exchange (ETDEWEB)

    Bireley, William R. [University of Colorado, Department of Radiology, Aurora, CO (United States); Van Hove, Johan L.K. [University of Colorado, Department of Genetics and Inherited Metabolic Diseases, Aurora, CO (United States); Gallagher, Renata C. [Children' s Hospital Colorado, Department of Genetics and Inherited Metabolic Diseases, Aurora, CO (United States); Fenton, Laura Z. [Children' s Hospital Colorado, Department of Pediatric Radiology, Aurora, CO (United States)

    2012-04-15

    Urea cycle disorders encompass several enzyme deficiencies that can result in cerebral damage, with a wide clinical spectrum from asymptomatic to severe. The goal of this study was to correlate brain MRI abnormalities in urea cycle disorders with clinical neurological sequelae to evaluate whether MRI abnormalities can assist in guiding difficult treatment decisions. We performed a retrospective chart review of patients with urea cycle disorders and symptomatic hyperammonemia. Brain MRI images were reviewed for abnormalities that correlated with severity of clinical neurological sequelae. Our case series comprises six urea cycle disorder patients, five with ornithine transcarbamylase deficiency and one with citrullinemia type 1. The observed trend in distribution of brain MRI abnormalities as the severity of neurological sequelae increased was the peri-insular region first, extending into the frontal, parietal, temporal and, finally, the occipital lobes. There was thalamic restricted diffusion in three children with prolonged hyperammonemia. Prior to death, this site is typically reported to be spared in urea cycle disorders. The pattern and extent of brain MRI abnormalities correlate with clinical neurological outcome in our case series. This suggests that brain MRI abnormalities may assist in determining prognosis and helping clinicians with subsequent treatment decisions. (orig.)

  2. Permeability dependence study of the focused ultrasound-induced blood-brain barrier opening at distinct pressures and microbubble diameters using DCE-MRI

    OpenAIRE

    Vlachos, Fotios; TUNG, YAO-SHENG; Konofagou, Elisa

    2011-01-01

    Blood-brain barrier (BBB) opening using focused ultrasound (FUS) and microbubbles has been experimentally established as a non-invasive and localized brain drug delivery technique. In this study, the permeability of the opening is assessed in the murine hippocampus after the application of FUS at three different acoustic pressures and microbubble sizes. Using DCE-MRI, the transfer rates were estimated, yielding permeability maps and quantitative Ktrans values for a predefined region of intere...

  3. Effect of Observation of Simple Hand Movement on Brain Activations in Patients with Unilateral Cerebral Palsy: An fMRI Study

    Science.gov (United States)

    Dinomais, Mickael; Lignon, Gregoire; Chinier, Eva; Richard, Isabelle; Minassian, Aram Ter; The Tich, Sylvie N'Guyen

    2013-01-01

    The aim of this functional magnetic resonance imaging (fMRI) study was to examine and compare brain activation in patients with unilateral cerebral palsy (CP) during observation of simple hand movement performed by the paretic and nonparetic hand. Nineteen patients with clinical unilateral CP (14 male, mean age 14 years, 7-21 years) participated…

  4. MRI findings of miliary tuberculosis of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Lak; Song, Chang June; Ahn, Young Jun; Youn, Wan Gyu; Jung, Youn Sin; Cho, June Sik [Chungnam National Univ. College of Medicine, Taejon (Korea, Republic of)

    1996-07-01

    To evaluate MRI(Magnetic Resonance Imaging) findings of miliary tuberculosis of the brain Six patients with miliary tuberculosis of the brain diagnosed by characteristic clinical or laboratory findings were studied with spin echo MRI before and after contrast enhancement. We retrospectively evaluated MRI findings according to the appearance, distribution, location, and enhancement pattern of the granulomas as well as associated other abnormalities. In six patients, contrast-enhanced MRI of the brain showed numerous punctate, contrast enhancing lesions scattered throughout the brain. Unenhanced MRI failed to demonstrate small granulomas except a few small foci of high signal intensity on T2-weighted images. The shapes of enhancing granulomas were homogeneous nodular enhancement in 86% of cases and small ring enhancement in 14%. 98% of granulomas were smaller than 3-mm and 2% were larger. Although several lesions were located in the basal ganglia, thalamus, and brain stem, the majority were located in the subpial and subarachnoid space. There was no significant difference in distribution of granulomas between the supratentorial and the infratentorial areas. Other associated abnormalities were focal meningitis in five cases and focal cerebritis in one. On chest radiograph, all patients had miliary tuberculosis in the lungs. Contrast-enhanced T1-weighted MR imaging showed numerous round, very small enhancing lesions scattered throughout the brain. The majority of lesions were located in the subpial and subarachnoid space. Contrast-enhanced T1-weighted images are helpful in the detection and diagnosis of miliary disseminated tuberculous granulomas and meningitis.

  5. Lithium alters brain activation in bipolar disorder in a task- and state-dependent manner: an fMRI study

    Directory of Open Access Journals (Sweden)

    Dave Sanjay

    2005-07-01

    Full Text Available Abstract Background It is unknown if medications used to treat bipolar disorder have effects on brain activation, and whether or not any such changes are mood-independent. Methods Patients with bipolar disorder who were depressed (n = 5 or euthymic (n = 5 were examined using fMRI before, and 14 days after, being started on lithium (as monotherapy in 6 of these patients. Patients were examined using a word generation task and verbal memory task, both of which have been shown to be sensitive to change in previous fMRI studies. Differences in blood oxygenated level dependent (BOLD magnitude between the pre- and post-lithium results were determined in previously defined regions of interest. Severity of mood was determined by the Hamilton Depression Scale for Depression (HAM-D and the Young mania rating scale (YMRS. Results The mean HAM-D score at baseline in the depressed group was 15.4 ± 0.7, and after 2 weeks of lithium it was 11.0 ± 2.6. In the euthymic group it was 7.6 ± 1.4 and 3.2 ± 1.3 respectively. At baseline mean BOLD signal magnitude in the regions of interest for the euthymic and depressed patients were similar in both the word generation task (1.56 ± 0.10 and 1.49 ± 0.10 respectively and working memory task (1.02 ± 0.04 and 1.12 ± 0.06 respectively. However, after lithium the mean BOLD signal decreased significantly in the euthymic group in the word generation task only (1.56 ± 0.10 to 1.00 ± 0.07, p Conclusion This is the first study to examine the effects of lithium on brain activation in bipolar patients. The results suggest that lithium has an effect on euthymic patients very similar to that seen in healthy volunteers. The same effects are not seen in depressed bipolar patients, although it is uncertain if this lack of change is linked to the lack of major improvements in mood in this group of patients. In conclusion, this study suggests that lithium may have effects on brain activation that are task- and state

  6. Studies of the correlations between morphological brain changes on MRI and computerized EEG changes in schizophrenics

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Kouzou (Kagoshima Univ. (Japan). Faculty of Medicine)

    1992-06-01

    Twenty eight schizophrenic patients, who ranged in age from 21 to 39 years with a mean of 30.2, and 21 age- and sex-matched normal volunteers were studied by magnetic resonance (MR) imaging and electroencephalography (EEG). ALl subjects were given informed consent prior to the present study. They were all right-handed. Schizophrenic patients showed a significantly larger ventricular brain ratio (VBR) on the axial and coronal planes as compared with the control. The bilateral anterior horns, left body, left posterior horn of the lateral ventricle and the third ventricle were significantly larger in schizophrenic patients than the control. The middle half of the corpus callosum was smaller in schizophrenic patients than the control. Schizophrenia was more likely associated not only with delta and theta activities in the centro-parieto-occipital regions but also with beta 1 and beta 2 activities in the front-central regions. In schizophrenic patients, however, alpha 2 activity was markedly decreased in all regions. There were significant positive correlations between the total scores for brief psychiatric rating scale (BPRS) and the areas of the left anterior and posterior horns of the lateral ventricle. The total BPRS scores positively correlated with the area of the third ventricle. In addition, positive correlations were significant between delata activity and the area of the left anterior horn of the lateral ventricle, between delta activity and the area of the third ventricle, and between beta 1 activity and the area of left posteior horn of the lateral ventricle. These results suggest that a dilated third ventricle is associated with electrophysiological brain pathology and psychopathology in schizophrenic patients. (N.K.) 76 refs.

  7. Applications of fMRI for Brain Mapping

    Directory of Open Access Journals (Sweden)

    Nivedita Daimiwal

    2012-11-01

    Full Text Available Brain-mapping techniques have proven to be vital in understanding the molecular, cellular, and functional mechanisms of the brain. Normal anatomical imaging can provide structural information on certain abnormalities in the brain. However there are many neurological disorders for which only structure studies are not sufficient. In such cases it is required to investigate the functional organization of the brain. Further it is necessary to study the brain functions under normal as well as diseased conditions. Brain mapping techniques can help in deriving useful and important information on these issues. Brain functions and brain area responsible for the particular activities like motor, sensory speech and memory process could be investigated. The authors provide an overview of various Brain Mapping techniques and fMRI signal processing methods.

  8. Changes in brain activation in stroke patients after mental practice and physical exercise:a functional MRI study

    Institute of Scientific and Technical Information of China (English)

    Hua Liu; Luping Song; Tong Zhang

    2014-01-01

    Mental practice is a new rehabilitation method that refers to the mental rehearsal of motor imagery content with the goal of improving motor performance. However, the relationship between activated regions and motor recovery after mental practice training is not well understood. In this study, 15 patients who suffered a first-ever subcortical stroke with neurological deficits affecting the right hand, but no significant cognitive impairment were recruited. 10 patients underwent mental practice combined with physical practice training, and 5 patients only underwent physical practice training. We observed brain activation regions after 4 weeks of training, and explored the correlation of activation changes with functional recovery of the affected hands. The results showed that, after 4 weeks of mental practice combined with physical training, the Fugl-Meyer assessment score for the affected right hand was significantly increased than that after 4 weeks of practice training alone. Functional MRI showed enhanced activation in the left primary somatosensory cortex, attenuated activation intensity in the right primary motor cortex, and enhanced right cerebellar activation observed during the motor imagery task using the affected right hand after mental practice training. The changes in brain cortical activity were related to functional recovery of the hand. Experimental findings indicate that cortical and cerebellar functional reorganization following mental practice contributed to the improvement of hand function.

  9. Brain correlates of aesthetic expertise: A parametric fMRI study

    DEFF Research Database (Denmark)

    Kirk, Ulrich; Skov, Martin; Christensen, Mark Schram

    2009-01-01

    of non-architects. This design allowed us to test whether level of expertise modulates neural activity in brain areas associated with either perceptual processing, memory, or reward processing. We show that experts and non-experts recruit bilateral medial orbitofrontal cortex (OFC) and subcallosal...... processing, but also modulates the response in reward related brain areas....

  10. Longitudinal assessment of blood-brain barrier leakage during epileptogenesis in rats. A quantitative MRI study.

    NARCIS (Netherlands)

    van Vliet, E.A.; Otte, W.M.; Gorter, J.A.; Dijkhuizen, R.M.; Wadman, W.J.

    2014-01-01

    The blood-brain barrier (BBB) plays an important role in the homeostasis of the brain. BBB dysfunction has been implicated in the pathophysiology of various neurological disorders, including epilepsy in which it may contribute to disease progression. Precise understanding of BBB dynamics during epil

  11. Pediatric brain MRI in neurofibromatosis type I

    Energy Technology Data Exchange (ETDEWEB)

    Mentzel, Hans-J.; Fitzek, Clemens; Vogt, Susanna; Reichenbach, Juergen R.; Kaiser, Werner A. [Friedrich-Schiller-University Jena, Department of Pediatric Radiology, Institute of Diagnostic and Interventional Radiology, Jena (Germany); Seidel, Joerg; Eichhorn, Annegret; Zintl, Felix [Friedrich-Schiller-University Jena, Department of Pediatrics, Jena (Germany)

    2005-04-01

    Neurofibromatosis (NF) is the most common of the phakomatoses, with a prevalence of 1 in 3-4,000. Many organ systems can be affected. In addition to multiple peripheral neurofibromas, NF I predisposed to CNS tumors including optic glioma, astrocytoma and plexiform neurofibroma. The purpose of this pictorial review is to illustrate characteristic brain MR imaging lesions in children with NF I and to give some recommendations about diagnostic imaging procedures in children suffering from NF I. Typical findings in brain MRI are hyperintense lesion on T2-weighted images, so-called unknown bright objects, which may be useful as an additional imaging criterion for NF I. Contrast administration is necessary in MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasm on follow-up examinations. We recommend to perform serial MR imaging in children every 12 months. The frequency of follow-up in children with known brain tumors will vary with the tumor grade, biological activity and treatment. (orig.)

  12. Atlas-Guided Segmentation of Vervet Monkey Brain MRI

    Science.gov (United States)

    Fedorov, Andriy; Li, Xiaoxing; Pohl, Kilian M; Bouix, Sylvain; Styner, Martin; Addicott, Merideth; Wyatt, Chris; Daunais, James B; Wells, William M; Kikinis, Ron

    2011-01-01

    The vervet monkey is an important nonhuman primate model that allows the study of isolated environmental factors in a controlled environment. Analysis of monkey MRI often suffers from lower quality images compared with human MRI because clinical equipment is typically used to image the smaller monkey brain and higher spatial resolution is required. This, together with the anatomical differences of the monkey brains, complicates the use of neuroimage analysis pipelines tuned for human MRI analysis. In this paper we developed an open source image analysis framework based on the tools available within the 3D Slicer software to support a biological study that investigates the effect of chronic ethanol exposure on brain morphometry in a longitudinally followed population of male vervets. We first developed a computerized atlas of vervet monkey brain MRI, which was used to encode the typical appearance of the individual brain structures in MRI and their spatial distribution. The atlas was then used as a spatial prior during automatic segmentation to process two longitudinal scans per subject. Our evaluation confirms the consistency and reliability of the automatic segmentation. The comparison of atlas construction strategies reveals that the use of a population-specific atlas leads to improved accuracy of the segmentation for subcortical brain structures. The contribution of this work is twofold. First, we describe an image processing workflow specifically tuned towards the analysis of vervet MRI that consists solely of the open source software tools. Second, we develop a digital atlas of vervet monkey brain MRIs to enable similar studies that rely on the vervet model. PMID:22253661

  13. Atlas-guided segmentation of vervet monkey brain MRI.

    Science.gov (United States)

    Fedorov, Andriy; Li, Xiaoxing; Pohl, Kilian M; Bouix, Sylvain; Styner, Martin; Addicott, Merideth; Wyatt, Chris; Daunais, James B; Wells, William M; Kikinis, Ron

    2011-01-01

    The vervet monkey is an important nonhuman primate model that allows the study of isolated environmental factors in a controlled environment. Analysis of monkey MRI often suffers from lower quality images compared with human MRI because clinical equipment is typically used to image the smaller monkey brain and higher spatial resolution is required. This, together with the anatomical differences of the monkey brains, complicates the use of neuroimage analysis pipelines tuned for human MRI analysis. In this paper we developed an open source image analysis framework based on the tools available within the 3D Slicer software to support a biological study that investigates the effect of chronic ethanol exposure on brain morphometry in a longitudinally followed population of male vervets. We first developed a computerized atlas of vervet monkey brain MRI, which was used to encode the typical appearance of the individual brain structures in MRI and their spatial distribution. The atlas was then used as a spatial prior during automatic segmentation to process two longitudinal scans per subject. Our evaluation confirms the consistency and reliability of the automatic segmentation. The comparison of atlas construction strategies reveals that the use of a population-specific atlas leads to improved accuracy of the segmentation for subcortical brain structures. The contribution of this work is twofold. First, we describe an image processing workflow specifically tuned towards the analysis of vervet MRI that consists solely of the open source software tools. Second, we develop a digital atlas of vervet monkey brain MRIs to enable similar studies that rely on the vervet model.

  14. Microvascular brain pathology on high resolution MRI

    NARCIS (Netherlands)

    Veluw, S.J. van

    2015-01-01

    Cerebral small vessel disease (SVD) is a common finding in the aging human brain and is associated with stroke, cognitive decline, and dementia. On autopsy, SVD encompasses pathological processes affecting small arteries and arterioles. Magnetic resonance imaging (MRI) detects the consequences of th

  15. Free Language Selection in the Bilingual Brain: An Event-Related fMRI Study.

    Science.gov (United States)

    Zhang, Yong; Wang, Tao; Huang, Peiyu; Li, Dan; Qiu, Jiang; Shen, Tong; Xie, Peng

    2015-01-01

    Bilingual speakers may select between two languages either on demand (forced language selection) or on their own volition (free language selection). However, the neural substrates underlying free and forced language selection may differ. While the neural substrates underlying forced language selection have been well-explored with language switching paradigms, those underlying free language selection have remained unclear. Using a modified digit-naming switching paradigm, we addressed the neural substrates underlying free language selection by contrasting free language switching with forced language switching. For a digit-pair trial, Chinese-English bilinguals named each digit in Chinese or English either on demand under forced language selection condition or on their own volition under free language selection condition. The results revealed activation in the frontoparietal regions that mediate volition of language selection. Furthermore, a comparison of free and forced language switching demonstrated differences in the patterns of brain activation. Additionally, free language switching showed reduced switching costs as compared to forced language switching. These findings suggest differences between the mechanism(s) underlying free and forced language switching. As such, the current study suggests interactivity between control of volition and control of language switching in free language selection, providing insights into a model of bilingual language control.

  16. Effect of "SOHAM" meditation on the human brain: an fMRI study.

    Science.gov (United States)

    Guleria, Anupam; Kumar, Uttam; Kishan, Sadguru Sri Kunal; Khetrapal, Chunni Lal

    2013-12-30

    The effect of "SOHAM" meditation has been investigated using functional magnetic resonance imaging (fMRI) in long-term meditators while they were meditating and not meditating. The results have revealed activation in left middle prefrontal cortex (MPFC) (Brodmann's area, BA 46), left inferior frontal gyrus (LIFG) (BA 44), left supplementary motor area (SMA) (BA 6) and left precuneus (BA 5) during the meditation period compared to the control period (no-meditation period). The results have been interpreted in terms of regulation of the emotional state, attention and working memory of the meditators.

  17. Regional characterization of longitudinal DT-MRI to study white matter maturation of the early developing brain.

    Science.gov (United States)

    Sadeghi, Neda; Prastawa, Marcel; Fletcher, P Thomas; Wolff, Jason; Gilmore, John H; Gerig, Guido

    2013-03-01

    The human brain undergoes rapid and dynamic development early in life. Assessment of brain growth patterns relevant to neurological disorders and disease requires a normative population model of growth and variability in order to evaluate deviation from typical development. In this paper, we focus on maturation of brain white matter as shown in diffusion tensor MRI (DT-MRI), measured by fractional anisotropy (FA), mean diffusivity (MD), as well as axial and radial diffusivities (AD, RD). We present a novel methodology to model temporal changes of white matter diffusion from longitudinal DT-MRI data taken at discrete time points. Our proposed framework combines nonlinear modeling of trajectories of individual subjects, population analysis, and testing for regional differences in growth pattern. We first perform deformable mapping of longitudinal DT-MRI of healthy infants imaged at birth, 1 year, and 2 years of age, into a common unbiased atlas. An existing template of labeled white matter regions is registered to this atlas to define anatomical regions of interest. Diffusivity properties of these regions, presented over time, serve as input to the longitudinal characterization of changes. We use non-linear mixed effect (NLME) modeling where temporal change is described by the Gompertz function. The Gompertz growth function uses intuitive parameters related to delay, rate of change, and expected asymptotic value; all descriptive measures which can answer clinical questions related to quantitative analysis of growth patterns. Results suggest that our proposed framework provides descriptive and quantitative information on growth trajectories that can be interpreted by clinicians using natural language terms that describe growth. Statistical analysis of regional differences between anatomical regions which are known to mature differently demonstrates the potential of the proposed method for quantitative assessment of brain growth and differences thereof. This will

  18. Brain network involved in visual processing of movement stimuli used in upper limb robotic training: an fMRI study

    Directory of Open Access Journals (Sweden)

    Nocchi Federico

    2012-07-01

    Full Text Available Abstract Background The potential of robot-mediated therapy and virtual reality in neurorehabilitation is becoming of increasing importance. However, there is limited information, using neuroimaging, on the neural networks involved in training with these technologies. This study was intended to detect the brain network involved in the visual processing of movement during robotic training. The main aim was to investigate the existence of a common cerebral network able to assimilate biological (human upper limb and non-biological (abstract object movements, hence testing the suitability of the visual non-biological feedback provided by the InMotion2 Robot. Methods A visual functional Magnetic Resonance Imaging (fMRI task was administered to 22 healthy subjects. The task required observation and retrieval of motor gestures and of the visual feedback used in robotic training. Functional activations of both biological and non-biological movements were examined to identify areas activated in both conditions, along with differential activity in upper limb vs. abstract object trials. Control of response was also tested by administering trials with congruent and incongruent reaching movements. Results The observation of upper limb and abstract object movements elicited similar patterns of activations according to a caudo-rostral pathway for the visual processing of movements (including specific areas of the occipital, temporal, parietal, and frontal lobes. Similarly, overlapping activations were found for the subsequent retrieval of the observed movement. Furthermore, activations of frontal cortical areas were associated with congruent trials more than with the incongruent ones. Conclusions This study identified the neural pathway associated with visual processing of movement stimuli used in upper limb robot-mediated training and investigated the brain’s ability to assimilate abstract object movements with human motor gestures. In both conditions

  19. Clinical applications of 7 T MRI in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Kolk, Anja G. van der, E-mail: A.G.vanderKolk@umcutrecht.nl [Department of Radiology, University Medical Center Utrecht, Postbox 85500, 3508 GA Utrecht (Netherlands); Hendrikse, Jeroen, E-mail: J.Hendrikse@umcutrecht.nl [Department of Radiology, University Medical Center Utrecht, Postbox 85500, 3508 GA Utrecht (Netherlands); Zwanenburg, Jaco J.M., E-mail: J.J.M.Zwanenburg@umcutrecht.nl [Department of Radiology, University Medical Center Utrecht, Postbox 85500, 3508 GA Utrecht (Netherlands); Image Sciences Institute, University Medical Center Utrecht (Netherlands); Visser, Fredy, E-mail: F.Visser-2@umcutrecht.nl [Department of Radiology, University Medical Center Utrecht, Postbox 85500, 3508 GA Utrecht (Netherlands); Philips Healthcare, Best (Netherlands); Luijten, Peter R., E-mail: P.Luijten@umcutrecht.nl [Department of Radiology, University Medical Center Utrecht, Postbox 85500, 3508 GA Utrecht (Netherlands)

    2013-05-15

    This review illustrates current applications and possible future directions of 7 Tesla (7 T) Magnetic Resonance Imaging (MRI) in the field of brain MRI, in clinical studies as well as clinical practice. With its higher signal-to-noise (SNR) and contrast-to-noise ratio (CNR) compared to lower field strengths, high resolution, contrast-rich images can be obtained of diverse pathologies, like multiple sclerosis (MS), brain tumours, aging-related changes and cerebrovascular diseases. In some of these diseases, additional pathophysiological information can be gained compared to lower field strengths. Because of clear depiction of small anatomical details, and higher lesion conspicuousness, earlier diagnosis and start of treatment of brain diseases may become possible. Furthermore, additional insight into the pathogenesis of brain diseases obtained with 7 T MRI could be the basis for new treatment developments. However, imaging at high field comes with several limitations, like inhomogeneous transmit fields, a higher specific absorption rate (SAR) and, currently, extensive contraindications for patient scanning. Future studies will be aimed at assessing the advantages and disadvantages of 7 T MRI over lower field strengths in light of clinical applications, specifically the additional diagnostic and prognostic value of 7 T MRI.

  20. Causes and Correlates of Brain Atrophy: A population-based MRI study

    NARCIS (Netherlands)

    T. den Heijer (Tom)

    2004-01-01

    markdownabstract__Abstract__ In 1906, Alois Alzheimer described for the first time a form of dementia that later became known as Alzheimer’s disease. At necropsy, he had observed that the brain of a 51-year-old woman with progressive cognitive decline was filled with –at that time still anonymous–

  1. A Study on the Application of Fuzzy Information Seeded Region Growing in Brain MRI Tissue Segmentation

    Directory of Open Access Journals (Sweden)

    Chuin-Mu Wang

    2014-01-01

    Full Text Available After long-term clinical trials, MRI has been proven to be used in humans harmlessly, and it is popularly used in medical diagnosis. Although MR is highly sensitive, it provides abundant organization information. Therefore, how to transform the multi-spectral images which is easier to be used for doctor’s clinical diagnosis. In this thesis, the fuzzy bidirectional edge detection method is used to solve conventional SRG problem of growing order in the initial seed stages. In order to overcome the problems of the different regions, although it is the same Euclidean distance for region growing and merging process stages, we present the peak detection method to improve them. The standard deviation target generation process (SDTGP is applied to guarantee the regions merging process does not cause over- or undersegmentation. Experimental results reveal that FISRG segments a multispectral MR image much more effectively than FAST and K-means.

  2. Age-related changes in brain hemodynamics; A calibrated MRI study

    DEFF Research Database (Denmark)

    De Vis, J B; Hendrikse, J; Bhogal, A;

    2015-01-01

    calculated. RESULTS: Whole brain CBF was 49 ± 14 and 40 ± 9 ml/100 g/min in young and older subjects respectively (P Age-related differences in CBF decreased to the point of nonsignificance (B=-4.1, SE=3.8) when EtCO2 was added as a confounder. BOLD CVR was lower in the whole brain, in the frontal......, in the temporal, and in the occipital of the older subjects (Pbrain OEF was 43 ± 8% in the young and 39 ± 6% in the older subjects (P = 0.066). Whole brain CMRO2 was 181 ± 60 and 133 ± 43 µmol/100 g/min in young and older subjects, respectively (PAge-related differences in CBF......INTRODUCTION: Blood oxygenation-level dependent (BOLD) magnetic resonance imaging signal changes in response to stimuli have been used to evaluate age-related changes in neuronal activity. Contradictory results from these types of experiments have been attributed to differences in cerebral blood...

  3. Brain activation evoked by erotic films varies with different menstrual phases: an fMRI study.

    Science.gov (United States)

    Zhu, Xun; Wang, Xiaoying; Parkinson, Carolyn; Cai, Chengxu; Gao, Song; Hu, Peicheng

    2010-01-20

    In humans, fluctuating hormone levels throughout the menstrual cycle are believed to regulate many cyclical sexual behaviors and motivational processes. However, there is a dearth of research investigating the neural correlates of this phenomenon. We used functional magnetic resonance imaging to identify brain regions involved in sexual arousal's regulatory process. Fifteen female participants were scanned while viewing erotic film excerpts at three time points during a single menstrual cycle: ovulation, menstruation, and at one additional time point. Tripled two-group differences analysis revealed that significant activation in the comparison was observed in non-ovulatory phases of the menstrual cycle in parts of the right inferior frontal gyrus, right lateral occipital cortex, and left postcentral gyrus, as well as in the bilateral superior parietal lobule. Thus, our results indicate that brain activity differs in the ovulatory phase of the menstrual cycle compared to during other menstrual phases. This finding provides neurological evidence for the ovulatory cycle's modulation of the processing of the sexual arousal in female human brain.

  4. Mapping human whole-brain structural networks with diffusion MRI.

    Directory of Open Access Journals (Sweden)

    Patric Hagmann

    Full Text Available Understanding the large-scale structural network formed by neurons is a major challenge in system neuroscience. A detailed connectivity map covering the entire brain would therefore be of great value. Based on diffusion MRI, we propose an efficient methodology to generate large, comprehensive and individual white matter connectional datasets of the living or dead, human or animal brain. This non-invasive tool enables us to study the basic and potentially complex network properties of the entire brain. For two human subjects we find that their individual brain networks have an exponential node degree distribution and that their global organization is in the form of a small world.

  5. Prospective demonstration of brain plasticity after intensive abacus-based mental calculation training: An fMRI study

    Science.gov (United States)

    Chen, C. L.; Wu, T. H.; Cheng, M. C.; Huang, Y. H.; Sheu, C. Y.; Hsieh, J. C.; Lee, J. S.

    2006-12-01

    Abacus-based mental calculation is a unique Chinese culture. The abacus experts can perform complex computations mentally with exceptionally fast speed and high accuracy. However, the neural bases of computation processing are not yet clearly known. This study used a BOLD contrast 3T fMRI system to explore the brain activation differences between abacus experts and non-expert subjects. All the acquired data were analyzed using SPM99 software. From the results, different ways of performing calculations between the two groups were seen. The experts tended to adopt efficient visuospatial/visuomotor strategy (bilateral parietal/frontal network) to process and retrieve all the intermediate and final results on the virtual abacus during calculation. By contrast, coordination of several networks (verbal, visuospatial processing and executive function) was required in the normal group to carry out arithmetic operations. Furthermore, more involvement of the visuomotor imagery processing (right dorsal premotor area) for imagining bead manipulation and low level use of the executive function (frontal-subcortical area) for launching the relatively time-consuming sequentially organized process was noted in the abacus expert group than in the non-expert group. We suggest that these findings may explain why abacus experts can reveal the exceptional computational skills compared to non-experts after intensive training.

  6. Prospective demonstration of brain plasticity after intensive abacus-based mental calculation training: An fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.L. [Faculty of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong St., Section 2, Taipei 112, Taiwan (China); Wu, T.H. [Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, 110, Section 1, Chien-Kuo N. Road, Taichung 402, Taiwan (China); Cheng, M.C. [Faculty of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong St., Section 2, Taipei 112, Taiwan (China); Huang, Y.H. [Faculty of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong St., Section 2, Taipei 112, Taiwan (China); Sheu, C.Y. [Department of Radiology, Mackay Memorial Hospital, 92, Section 2, Chungshan North Road, Taipei 104, Taiwan (China); Hsieh, J.C. [Integrated Brain Research Unit, Taipei Veterans General Hospital, 201, Section 2, Shih-Pai Road, Taipei 112, Taiwan (China); Lee, J.S. [Faculty of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong St., Section 2, Taipei 112, Taiwan (China)]. E-mail: jslee@ym.edu.tw

    2006-12-20

    Abacus-based mental calculation is a unique Chinese culture. The abacus experts can perform complex computations mentally with exceptionally fast speed and high accuracy. However, the neural bases of computation processing are not yet clearly known. This study used a BOLD contrast 3T fMRI system to explore the brain activation differences between abacus experts and non-expert subjects. All the acquired data were analyzed using SPM99 software. From the results, different ways of performing calculations between the two groups were seen. The experts tended to adopt efficient visuospatial/visuomotor strategy (bilateral parietal/frontal network) to process and retrieve all the intermediate and final results on the virtual abacus during calculation. By contrast, coordination of several networks (verbal, visuospatial processing and executive function) was required in the normal group to carry out arithmetic operations. Furthermore, more involvement of the visuomotor imagery processing (right dorsal premotor area) for imagining bead manipulation and low level use of the executive function (frontal-subcortical area) for launching the relatively time-consuming sequentially organized process was noted in the abacus expert group than in the non-expert group. We suggest that these findings may explain why abacus experts can reveal the exceptional computational skills compared to non-experts after intensive training.

  7. Visioning in the brain: an fMRI study of inspirational coaching and mentoring.

    Science.gov (United States)

    Jack, Anthony I; Boyatzis, Richard E; Khawaja, Masud S; Passarelli, Angela M; Leckie, Regina L

    2013-01-01

    Effective coaching and mentoring is crucial to the success of individuals and organizations, yet relatively little is known about its neural underpinnings. Coaching and mentoring to the Positive Emotional Attractor (PEA) emphasizes compassion for the individual's hopes and dreams and has been shown to enhance a behavioral change. In contrast, coaching to the Negative Emotional Attractor (NEA), by focusing on externally defined criteria for success and the individual's weaknesses in relation to them, does not show sustained change. We used fMRI to measure BOLD responses associated with these two coaching styles. We hypothesized that PEA coaching would be associated with increased global visual processing and with engagement of the parasympathetic nervous system (PNS), while the NEA coaching would involve greater engagement of the sympathetic nervous system (SNS). Regions showing more activity in PEA conditions included the lateral occipital cortex, superior temporal cortex, medial parietal, subgenual cingulate, nucleus accumbens, and left lateral prefrontal cortex. We relate these activations to visioning, PNS activity, and positive affect. Regions showing more activity in NEA conditions included medial prefrontal regions and right lateral prefrontal cortex. We relate these activations to SNS activity, self-trait attribution and negative affect.

  8. Study of CT, MRI and pathology in experimental brain abscess%实验性脑脓肿的CT、MRI和病理特征分析

    Institute of Scientific and Technical Information of China (English)

    赵春生; 杨树源

    2001-01-01

    目的研究实验性脑脓肿不同时期的CT、MRI及病理特征。方法建立狗脑脓肿模型,应用动态CT、MRI检查,结合多项病理学观测进行分析。结果脑炎期MRI T1成像中心坏死区为低信号边缘不清,T2成像上为高信号,且与高信号水肿区融为一体,其范围比CT低密度区广泛。包膜期T1成像上包膜为等或略高信号,T2成像上为一光滑的、薄的、不连续的低信号“带”,其机理可能是脓肿壁上巨噬细胞产生的自由基不均匀分布所致。结论脑脓肿MRI特征与其临床分期及病理学变化的相关性较好,能更加准确、迅速区别脓肿的脑炎期和包膜形成期。%Objective To study the correlation of CT,MRI and pathology in experimental brain abscess.Methods An experimental model of brain in dogs was developed to study the feature of CT and MRI of various stage of brain abscess and pathological bases.Results The MRI appearance of cerebritis stage showed central necrosis producing mild hypointensity signal relative to brain tissue on T1-weighted,while central necrosis and surrounding edematous brain tissue showing high intensity signals on T1-weighted.The high-intensity signals region was more extensive than the contrast-enhanced lesion seen on CT.The MRI features of well encapsulated abscess showed peripheral edema producing mild hypointensity signals on T1-weighted and marked hyperintensity signals on T2-weighted,central necrosis with abscess fluid hypointense signals relative to brain tissue and hyperintense signals relative to CSF on T1-weighted and hyperintense signal relative to brain tissue on T2-weighted as well.Visualizaion of the abscess capsule was iso-to mildly hyperintense signal relatiove to brain tissue on T1-weighted.The rims of hypointensity signals on T2-weighted were thin smooth.The hypointense rims on T2-weighted of MRI is likely due to the presence of heterogeneously

  9. Moral competence and brain connectivity: A resting-state fMRI study.

    Science.gov (United States)

    Jung, Wi Hoon; Prehn, Kristin; Fang, Zhuo; Korczykowski, Marc; Kable, Joseph W; Rao, Hengyi; Robertson, Diana C

    2016-11-01

    Moral competence (MC) refers to the ability to apply certain moral orientations in a consistent and differentiated manner when judging moral issues. People greatly differ in terms of MC, however, little is known about how these differences are implemented in the brain. To investigate this question, we used functional magnetic resonance imaging and examined resting-state functional connectivity (RSFC) in n=31 individuals with MC scores in the highest 15% of the population and n=33 individuals with MC scores in the lowest 15%, selected from a large sample of 730 Master of Business Administration (MBA) students. Compared to individuals with lower MC, individuals with higher MC showed greater amygdala-ventromedial prefrontal connectivity, which may reflect better ability to cope with emotional conflicts elicited by moral dilemmas. Moreover, individuals with higher MC showed less inter-network connectivity between the amygdalar and fronto-parietal networks, suggesting a more independent operation of these networks. Our findings provide novel insights into how individual differences in moral judgment are associated with RSFC in brain circuits related to emotion processing and cognitive control.

  10. Tissue tracking: applications for brain MRI classification

    Science.gov (United States)

    Melonakos, John; Gao, Yi; Tannenbaum, Allen

    2007-03-01

    Bayesian classification methods have been extensively used in a variety of image processing applications, including medical image analysis. The basic procedure is to combine data-driven knowledge in the likelihood terms with clinical knowledge in the prior terms to classify an image into a pre-determined number of classes. In many applications, it is difficult to construct meaningful priors and, hence, homogeneous priors are assumed. In this paper, we show how expectation-maximization weights and neighboring posterior probabilities may be combined to make intuitive use of the Bayesian priors. Drawing upon insights from computer vision tracking algorithms, we cast the problem in a tissue tracking framework. We show results of our algorithm on the classification of gray and white matter along with surrounding cerebral spinal fluid in brain MRI scans. We show results of our algorithm on 20 brain MRI datasets along with validation against expert manual segmentations.

  11. Brain MRI findings in Wernicke encephalopathy.

    Science.gov (United States)

    Wicklund, Meredith R; Knopman, David S

    2013-08-01

    A 71-year-old woman with myelofibrosis on chemotherapy experienced an acute illness with nausea, vomiting, and diarrhea. Two weeks later, she developed an acute confusional state characterized by disorientation and fluctuating alertness with normal speech and language. Her neurologic examination demonstrated an upper motor neuron pattern of right hemiparesis. She reported double vision though ophthalmoparesis was not appreciated. Her gait was normal. While hospitalized, she developed generalized tonic-clonic seizures. Brain MRI revealed a small area of restricted diffusion of the left precentral gyrus (figure). She was diagnosed with a stroke with secondary seizures; however, as the confusional state resolved, she developed profound retrograde and anterograde amnesia. Review of the brain MRI showed high T2 signal in the medial thalamus and contrast enhancement of the mamillary bodies; a diagnosis of Wernicke-Korsakoff syndrome was entertained and she was started on thiamine replacement. The encephalopathy and hemiparesis resolved though she remains severely amnestic.

  12. Brain MRI findings of neuropsychiatric lupus

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jang-Wook; Kwon, Bae Ju; Lee, Seung-Ro; Hahm, Chang-Kok; Moon, Won Jin; Jeon, Eui Yong; Bae, Sang-Chul [Hanyang Univ. School of Medicine, Seoul (Korea, Republic of)

    2000-12-01

    To evaluate the brain MRI findings in patients with neuropsychiatric lupus. In 26 patients (M:F = 2:24 ; aged 9-48 years) in whom the presence of systemic lupus erythematosus was clinically or pathologically proven and in whom neuropsychiatric lupus was also clinically diagnosed, the findings of brain MRI were retrospectively evaluated. MR images were analyzed with regard to the distribution, location, size and number of lesions due to cerebral ischemia or infarction, the presence of cerebral atrophy, and the extent and degree of brain parenchymal and intravascular enhancement. The most common MRI findings were lesions due to cerebral ischemia or infarction occurring in 18 patients (69%), and located within deep periventricular white matter (n=10), subcortical white matter (n=8), the cerebral cortex (n=7), basal ganglia (n=7), or brain stem or cerebellum (n=2). The lesions were single (n=3) or multiple (n=15), and in 17 patients were less than 1cm in diameter in regions other than the cerebral cortex. In six of these patients, lesions of 1-4cm in diameter in this region were combined, and one occurred in the cerebral cortex only. Cerebral atrophy was seen in 16 patients (62%), in ten of whom there was no past history of treatment with steroids for more than six months. In 15 patients (58%), contrast-enhanced MR image revealed diffuse enhancement of the basal ganglia or intravascular enhancement. In no case were MRI findings normal. The primary mainfestations of neuropsychiatric lupus are multifocal ischemia or infarctions in the cerebral cortex, and subcortical and deep white matter, and the cerebral atrophy. Contrast-enhanced MR images also demonstrated diffuse enhancement of the basal ganglia and intravascular enhancement, both thought to be related to the congestion due to the stagnation of cerebral blood flow.

  13. Brain palpation from physiological vibrations using MRI

    OpenAIRE

    2015-01-01

    It is commonly supposed that noise obscures but does not contain useful information. However, in wave physics and especially, seismology, scientists developed some tools known as “noise correlation” to extract useful information and construct images from the random vibrations of a medium. Living tissues are full of unexploited vibrations as well. In this manuscript, we show that noise correlation techniques in the brain using MRI can conduct to a tomography related to the stiffness that physi...

  14. Optimizing full-brain coverage in human brain MRI through population distributions of brain size.

    Science.gov (United States)

    Mennes, Maarten; Jenkinson, Mark; Valabregue, Romain; Buitelaar, Jan K; Beckmann, Christian; Smith, Stephen

    2014-09-01

    When defining an MRI protocol, brain researchers need to set multiple interdependent parameters that define repetition time (TR), voxel size, field-of-view (FOV), etc. Typically, researchers aim to image the full brain, making the expected FOV an important parameter to consider. Especially in 2D-EPI sequences, non-wasteful FOV settings are important to achieve the best temporal and spatial resolution. In practice, however, imperfect FOV size estimation often results in partial brain coverage for a significant number of participants per study, or, alternatively, an unnecessarily large voxel-size or number of slices to guarantee full brain coverage. To provide normative FOV guidelines we estimated population distributions of brain size in the x-, y-, and z-direction using data from 14,781 individuals. Our results indicated that 11mm in the z-direction differentiate between obtaining full brain coverage for 90% vs. 99.9% of participants. Importantly, we observed that rotating the FOV to optimally cover the brain, and thus minimize the number of slices needed, effectively reduces the required inferior-superior FOV size by ~5%. For a typical adult imaging study, 99.9% of the population can be imaged with full brain coverage when using an inferior-superior FOV of 142mm, assuming optimal slice orientation and minimal within-scan head motion. By providing population distributions for brain size in the x-, y-, and z-direction we improve the potential for obtaining full brain coverage, especially in 2D-EPI sequences used in most functional and diffusion MRI studies. We further enable optimization of related imaging parameters including the number of slices, TR and total acquisition time.

  15. A cross-sectional MRI study of brain regional atrophy and clinical characteristics of temporal lobe epilepsy with hippocampal sclerosis.

    LENUS (Irish Health Repository)

    2012-02-01

    PURPOSE: Applying a cross-sectional design, we set out to further characterize the significance of extrahippocampal brain atrophy in a large sample of \\'sporadic\\' mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE+HS). By evaluating the influence of epilepsy chronicity on structural atrophy, this work represents an important step towards the characterization of MRI-based volumetric measurements as genetic endophenotypes for this condition. METHODS: Using an automated brain segmentation technique, MRI-based volume measurements of several brain regions were compared between 75 patients with \\'sporadic\\' MTLE+HS and 50 healthy controls. Applying linear regression models, we examined the relationship between structural atrophy and important clinical features of MTLE+HS, including disease duration, lifetime number of partial and generalized seizures, and history of initial precipitating insults (IPIs). RESULTS: Significant volume loss was detected in ipsilateral hippocampus, amygdala, thalamus, and cerebral white matter (WM). In addition, contralateral hippocampal and bilateral cerebellar grey matter (GM) volume loss was observed in left MTLE+HS patients. Hippocampal, amygdalar, and cerebral WM volume loss correlated with duration of epilepsy. This correlation was stronger in patients with prior IPIs history. Further, cerebral WM, cerebellar GM, and contralateral hippocampal volume loss correlated with lifetime number of generalized seizures. CONCLUSION: Our findings confirm that multiple brain regions beyond the hippocampus are involved in the pathogenesis of MTLE+HS. IPIs are an important factor influencing the rate of regional atrophy but our results also support a role for processes related to epilepsy chronicity. The consequence of epilepsy chronicity on candidate brain regions has important implications on their application as genetic endophenotypes.

  16. MRI Helps Assess Fetal Brain Abnormalities

    Science.gov (United States)

    ... authors. The study was published Dec. 14 in The Lancet . "Adding an MRI scan when a problem is ... practice as soon as possible, he said. SOURCE: The Lancet , news release, Dec. 14, 2016 HealthDay Copyright (c) ...

  17. 婴幼儿颅脑MRI扫描技术的探讨%Study on Infant Brain MRI Scan Techniques

    Institute of Scientific and Technical Information of China (English)

    范宪淼; 郑晓林; 肖利华; 张坤林; 吴凤英

    2013-01-01

    Objective To evaluate infant brain MRI scan techniques and the diagnostic value in displaying focuses.Methods Brain MRI scanning were performed to 55 infants.The adopted sequences were T1WI Sag,T2WI Tra,T1WI Tra,FLAIR Cor and DWI Tra.The total time of examination was 8 minutes and 30 seconds.The contrast of gray matter and white matter of brain was evaluated and manifestations of various diseases were observed.Results Of 55 cases,images of 52 cases met the qualification to diagnose,and the successful rate was 92%.The brain stem,thalamus and basal ganglia of 15 normal mature infants were showed high signal in T 1WI and low signal in T2WI.Flatten gyrus and shoal brain channel was showed in 13 immature infant.In 15 cases with hypoxic ischemic encephalopathy,newborns with white matter bleeding showed focal high signal in T1WI and low signal in T2WI,and newborns with brain soften focus showed focal low signal in T1WI and high signal in T2WI sub cortex,in white matter and subependymal.The focuses of trauma and malformation of brain could be displayed in MRI.Conclusions Brain MRI scan techniques could display brain structure,myelinization and various diseases.It had important clinical application values.%目的 探讨婴幼儿颅脑MRI扫描技术及其显示病变的诊断价值.方法 对5 5例婴幼儿进行颅脑MRI检查,所用序列为T1WI Sag,T2WI Tra,T1WITra,FLAIR Cor,DWI Tra,全部检查时间为8分30秒.评价图像显示灰白质等结构的对比,观察不同病变的MRI表现.结果 55例患儿52例图像达到诊断要求,成功率为92%.正常足月婴儿1 5例表现为脑干、丘脑、基底节T1WI高信号,T2WI低信号.早产儿13例表现为脑回变平,脑沟浅而不清.新生儿缺血缺氧性脑病15例中,脑白质出血灶表现为局灶性T1WI高信号、T2WI低信号,脑软化灶表现为皮质下、白质、室管膜下T2WI低信号,T2WI高信号.外伤、脑发育畸形等均可显示其病变.结论 颅脑MRI扫描技术能显示婴幼

  18. Dynamic Contrast-Enhanced MRI in the Study of Brain Tumors. Comparison Between the Extended Tofts-Kety Model and a Phenomenological Universalities (PUN) Algorithm.

    Science.gov (United States)

    Bergamino, Maurizio; Barletta, Laura; Castellan, Lucio; Mancardi, Gianluigi; Roccatagliata, Luca

    2015-12-01

    Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a well-established technique for studying blood-brain barrier (BBB) permeability that allows measurements to be made for a wide range of brain pathologies, including multiple sclerosis and brain tumors (BT). This latter application is particularly interesting, because high-grade gliomas are characterized by increased microvascular permeability and a loss of BBB function due to the structural abnormalities of the endothelial layer. In this study, we compared the extended Tofts-Kety (ETK) model and an extended derivate class from phenomenological universalities called EU1 in 30 adult patients with different BT grades. A total of 75 regions of interest were manually drawn on the MRI and subsequently analyzed using the ETK and EU1 algorithms. Significant linear correlations were found among the parameters obtained by these two algorithms. The means of R (2) obtained using ETK and EU1 models for high-grade tumors were 0.81 and 0.91, while those for low-grade tumors were 0.82 and 0.85, respectively; therefore, these two models are equivalent. In conclusion, we can confirm that the application of the EU1 model to the DCE-MRI experimental data might be a useful alternative to pharmacokinetic models in the study of BT, because the analytic results can be generated more quickly and easily than with the ETK model.

  19. Patterns of brain activation when mothers view their own child and dog: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Luke E Stoeckel

    Full Text Available Neural substrates underlying the human-pet relationship are largely unknown. We examined fMRI brain activation patterns as mothers viewed images of their own child and dog and an unfamiliar child and dog. There was a common network of brain regions involved in emotion, reward, affiliation, visual processing and social cognition when mothers viewed images of both their child and dog. Viewing images of their child resulted in brain activity in the midbrain (ventral tegmental area/substantia nigra involved in reward/affiliation, while a more posterior cortical brain activation pattern involving fusiform gyrus (visual processing of faces and social cognition characterized a mother's response to her dog. Mothers also rated images of their child and dog as eliciting similar levels of excitement (arousal and pleasantness (valence, although the difference in the own vs. unfamiliar child comparison was larger than the own vs. unfamiliar dog comparison for arousal. Valence ratings of their dog were also positively correlated with ratings of the attachment to their dog. Although there are similarities in the perceived emotional experience and brain function associated with the mother-child and mother-dog bond, there are also key differences that may reflect variance in the evolutionary course and function of these relationships.

  20. Unexplained mental retardation: is brain MRI useful?

    Energy Technology Data Exchange (ETDEWEB)

    Decobert, Fabrice; Merzoug, Valerie; Kalifa, Gabriel; Adamsbaum, Catherine [Saint Vincent de Paul Hospital, Department of Radiology, 75674 Paris Cedex 14 (France); Grabar, Sophie [Cochin Hospital, Department of Biostatistics and Medical Information, Paris (France); Ponsot, Gerard [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Des Portes, Vincent [Saint Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Debrousse Hospital, Department of Neuropaediatrics, Lyon (France)

    2005-06-01

    Mental retardation (MR), defined as an IQ below 70, is a frequent cause of consultation in paediatrics. To evaluate the yield of brain MRI in the diagnostic work-up of unexplained MR in children. Patients and methods: The MRI features and clinical data of 100 patients (age 1-18 years) affected with non-progressive MR of unknown origin were compared to an age-matched control group (n=100). Two radiologists conducted an independent review of the MRI scans. Univariate and multivariate analyses showed a higher incidence of brain anomalies in the MR group than in the control group (53 vs 17, OR=5.7 [2.9-11.1]), for signal abnormalities within the periventricular white matter (OR=20.3 [2.6-155.3]), lateral ventricular dilatation (OR=15.6 [2.0-124]), mild corpus callosum abnormalities (shortness, atrophy) (OR=6.8 [1.8-25.6]) and subtle cerebellar abnormalities, including fissure enlargement (OR=5.2 [1.1-26.2]). The diagnostic value of MRI abnormalities was considered good in 5% of patients (Alexander disease n=1, diffuse cortical malformation n=1, leukomalacia n=1, vermian agenesis n=1, commissural agenesis n=1), and weak in 48% of patients, in whom non-specific abnormalities did not lead to a diagnosis. Some clinical features resulted in a significantly higher percentage of abnormal MRI scans: abnormal neurological examination (82% vs 47%, P=0.008), abnormal skull circumference (66% vs 49%, P=0.04). Motor delay was associated with cerebellar abnormalities (P=0.01). (orig.)

  1. Structural and functional correlates of visual field asymmetry in the human brain by diffusion kurtosis MRI and functional MRI.

    Science.gov (United States)

    O'Connell, Caitlin; Ho, Leon C; Murphy, Matthew C; Conner, Ian P; Wollstein, Gadi; Cham, Rakie; Chan, Kevin C

    2016-11-09

    Human visual performance has been observed to show superiority in localized regions of the visual field across many classes of stimuli. However, the underlying neural mechanisms remain unclear. This study aims to determine whether the visual information processing in the human brain is dependent on the location of stimuli in the visual field and the corresponding neuroarchitecture using blood-oxygenation-level-dependent functional MRI (fMRI) and diffusion kurtosis MRI, respectively, in 15 healthy individuals at 3 T. In fMRI, visual stimulation to the lower hemifield showed stronger brain responses and larger brain activation volumes than the upper hemifield, indicative of the differential sensitivity of the human brain across the visual field. In diffusion kurtosis MRI, the brain regions mapping to the lower visual field showed higher mean kurtosis, but not fractional anisotropy or mean diffusivity compared with the upper visual field. These results suggested the different distributions of microstructural organization across visual field brain representations. There was also a strong positive relationship between diffusion kurtosis and fMRI responses in the lower field brain representations. In summary, this study suggested the structural and functional brain involvements in the asymmetry of visual field responses in humans, and is important to the neurophysiological and psychological understanding of human visual information processing.

  2. Risperidone Effects on Brain Dynamic Connectivity—A Prospective Resting-State fMRI Study in Schizophrenia

    Science.gov (United States)

    Lottman, Kristin K.; Kraguljac, Nina V.; White, David M.; Morgan, Charity J.; Calhoun, Vince D.; Butt, Allison; Lahti, Adrienne C.

    2017-01-01

    Resting-state functional connectivity studies in schizophrenia evaluating average connectivity over the entire experiment have reported aberrant network integration, but findings are variable. Examining time-varying (dynamic) functional connectivity may help explain some inconsistencies. We assessed dynamic network connectivity using resting-state functional MRI in patients with schizophrenia, while unmedicated (n = 34), after 1 week (n = 29) and 6 weeks of treatment with risperidone (n = 24), as well as matched controls at baseline (n = 35) and after 6 weeks (n = 19). After identifying 41 independent components (ICs) comprising resting-state networks, sliding window analysis was performed on IC timecourses using an optimal window size validated with linear support vector machines. Windowed correlation matrices were then clustered into three discrete connectivity states (a relatively sparsely connected state, a relatively abundantly connected state, and an intermediately connected state). In unmedicated patients, static connectivity was increased between five pairs of ICs and decreased between two pairs of ICs when compared to controls, dynamic connectivity showed increased connectivity between the thalamus and somatomotor network in one of the three states. State statistics indicated that, in comparison to controls, unmedicated patients had shorter mean dwell times and fraction of time spent in the sparsely connected state, and longer dwell times and fraction of time spent in the intermediately connected state. Risperidone appeared to normalize mean dwell times after 6 weeks, but not fraction of time. Results suggest that static connectivity abnormalities in schizophrenia may partly be related to altered brain network temporal dynamics rather than consistent dysconnectivity within and between functional networks and demonstrate the importance of implementing complementary data analysis techniques. PMID:28220083

  3. Intraoperative MRI in pediatric brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Choudhri, Asim F. [Le Bonheur Children' s Hospital, Department of Radiology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Neurosurgery, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Ophthalmology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Siddiqui, Adeel [University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Klimo, Paul; Boop, Frederick A. [University of Tennessee Health Science Center, Department of Neurosurgery, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Semmes-Murphey Neurologic and Spine Institute, Memphis, TN (United States); St. Jude Children' s Hospital, Division of Neurosurgery, Department of Surgery, Memphis, TN (United States)

    2015-09-15

    Intraoperative magnetic resonance imaging (iMRI) has emerged as an important tool in guiding the surgical management of children with brain tumors. Recent advances have allowed utilization of high field strength systems, including 3-tesla MRI, resulting in diagnostic-quality scans that can be performed while the child is on the operating table. By providing information about the possible presence of residual tumor, it allows the neurosurgeon to both identify and resect any remaining tumor that is thought to be safely accessible. By fusing the newly obtained images with the surgical guidance software, the images have the added value of aiding in navigation to any residual tumor. This is important because parenchyma often shifts during surgery. It also gives the neurosurgeon insight into whether any immediate postoperative complications have occurred. If any complications have occurred, the child is already in the operating room and precious minutes lost in transport and communications are saved. In this article we review the three main approaches to an iMRI system design. We discuss the possible roles for iMRI during intraoperative planning and provide guidance to help radiologists and neurosurgeons alike in the collaborative management of these children. (orig.)

  4. How skill expertise shapes the brain functional architecture: an fMRI study of visuo-spatial and motor processing in professional racing-car and naive drivers.

    Directory of Open Access Journals (Sweden)

    Giulio Bernardi

    Full Text Available The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI, we measured brain activity while eleven Formula racing-car drivers and eleven 'naïve' volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both 'quantitative' and 'qualitative' modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased 'neural efficiency' in the brain of highly skilled individuals.

  5. In vitro MRI of brain development

    Energy Technology Data Exchange (ETDEWEB)

    Rados, Marko [Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 12, 10000 Zagreb (Croatia); Clinical Hospital Center Zagreb, School of Medicine, University of Zagreb, Kispaticeva 12, 10000 Zagreb (Croatia); Judas, Milos [Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 12, 10000 Zagreb (Croatia); Kostovic, Ivica [Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 12, 10000 Zagreb (Croatia)]. E-mail: ikostov@hiim.h

    2006-02-15

    In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular zone. The basal ganglia showed an initial aggregation of cells. The most massive fiber system is in the hemispheric stalk, which is in continuity with thalamocortical fibers. During the mid-fetal period (15-22 postovulatory weeks), the typical fetal lamination pattern develops and the cerebral wall consists of the following zones: (a) a marginal zone (visible on MRI exclusively in the hippocampus); (b) the cortical plate with high cell-packing density and high MRI signal intensity; (c) the subplate zone, which is the most prominent zone rich in extracellular matrix and with a very low MRI signal intensity; (d) the intermediate zone (fetal 'white matter'); (e) the subventricular zone; (f) the periventricular fiber-rich zone; (g) the ventricular zone. The ganglionic eminence is still a very prominent structure with an intense proliferative activity. During the next period (22-26 postovulatory weeks), there is the developmental peak of transient MRI features, caused by the high content of hydrophyllic extracellular matrix in the subplate zone and the

  6. Age-related brain trajectories in schizophrenia: a systematic review of structural MRI studies.

    Science.gov (United States)

    Chiapponi, Chiara; Piras, Fabrizio; Fagioli, Sabrina; Piras, Federica; Caltagirone, Carlo; Spalletta, Gianfranco

    2013-11-30

    Using the Pubmed database, we performed a detailed literature search for structural magnetic resonance imaging studies on patients with schizophrenia, investigating the relationship between macroscopic and microscopic structural parameters and age, to delineate an age-related trajectory. Twenty-six studies were considered for the review, from January 2000 to June 2012. Research results are heterogeneous because of the multifactorial features of schizophrenia and the multiplicity of the methodological approaches adopted. Some areas, within the amygdala-hippocampus complex, which are affected early in life by schizophrenia, age in a physiological way. Other regions, such as the superior temporal gyrus, appear already impaired at the onset of symptoms, undergo a worsening in the acute phase but later stabilize, progressing physiologically over years. Finally, there are regions, such as the uncinate fasciculus, which are not altered early in life, but are affected around the onset of schizophrenia, with their impairment continuously worsening over time. Further extensive longitudinal studies are needed to understand the timing and the possible degenerative characteristics of structural impairment associated with schizophrenia.

  7. Convergent Findings of Altered Functional and Structural Brain Connectivity in Individuals with High Functioning Autism: A Multimodal MRI Study.

    Science.gov (United States)

    Mueller, Sophia; Keeser, Daniel; Samson, Andrea C; Kirsch, Valerie; Blautzik, Janusch; Grothe, Michel; Erat, Okan; Hegenloh, Michael; Coates, Ute; Reiser, Maximilian F; Hennig-Fast, Kristina; Meindl, Thomas

    2013-01-01

    Brain tissue changes in autism spectrum disorders seem to be rather subtle and widespread than anatomically distinct. Therefore a multimodal, whole brain imaging technique appears to be an appropriate approach to investigate whether alterations in white and gray matter integrity relate to consistent changes in functional resting state connectivity in individuals with high functioning autism (HFA). We applied diffusion tensor imaging (DTI), voxel-based morphometry (VBM) and resting state functional connectivity magnetic resonance imaging (fcMRI) to assess differences in brain structure and function between 12 individuals with HFA (mean age 35.5, SD 11.4, 9 male) and 12 healthy controls (mean age 33.3, SD 9.0, 8 male). Psychological measures of empathy and emotionality were obtained and correlated with the most significant DTI, VBM and fcMRI findings. We found three regions of convergent structural and functional differences between HFA participants and controls. The right temporo-parietal junction area and the left frontal lobe showed decreased fractional anisotropy (FA) values along with decreased functional connectivity and a trend towards decreased gray matter volume. The bilateral superior temporal gyrus displayed significantly decreased functional connectivity that was accompanied by the strongest trend of gray matter volume decrease in the temporal lobe of HFA individuals. FA decrease in the right temporo-parietal region was correlated with psychological measurements of decreased emotionality. In conclusion, our results indicate common sites of structural and functional alterations in higher order association cortex areas and may therefore provide multimodal imaging support to the long-standing hypothesis of autism as a disorder of impaired higher-order multisensory integration.

  8. Convergent Findings of Altered Functional and Structural Brain Connectivity in Individuals with High Functioning Autism: A Multimodal MRI Study.

    Directory of Open Access Journals (Sweden)

    Sophia Mueller

    Full Text Available Brain tissue changes in autism spectrum disorders seem to be rather subtle and widespread than anatomically distinct. Therefore a multimodal, whole brain imaging technique appears to be an appropriate approach to investigate whether alterations in white and gray matter integrity relate to consistent changes in functional resting state connectivity in individuals with high functioning autism (HFA. We applied diffusion tensor imaging (DTI, voxel-based morphometry (VBM and resting state functional connectivity magnetic resonance imaging (fcMRI to assess differences in brain structure and function between 12 individuals with HFA (mean age 35.5, SD 11.4, 9 male and 12 healthy controls (mean age 33.3, SD 9.0, 8 male. Psychological measures of empathy and emotionality were obtained and correlated with the most significant DTI, VBM and fcMRI findings. We found three regions of convergent structural and functional differences between HFA participants and controls. The right temporo-parietal junction area and the left frontal lobe showed decreased fractional anisotropy (FA values along with decreased functional connectivity and a trend towards decreased gray matter volume. The bilateral superior temporal gyrus displayed significantly decreased functional connectivity that was accompanied by the strongest trend of gray matter volume decrease in the temporal lobe of HFA individuals. FA decrease in the right temporo-parietal region was correlated with psychological measurements of decreased emotionality. In conclusion, our results indicate common sites of structural and functional alterations in higher order association cortex areas and may therefore provide multimodal imaging support to the long-standing hypothesis of autism as a disorder of impaired higher-order multisensory integration.

  9. Putting age-related task activation into large-scale brain networks: A meta-analysis of 114 fMRI studies on healthy aging.

    Science.gov (United States)

    Li, Hui-Jie; Hou, Xiao-Hui; Liu, Han-Hui; Yue, Chun-Lin; Lu, Guang-Ming; Zuo, Xi-Nian

    2015-10-01

    Normal aging is associated with cognitive decline and underlying brain dysfunction. Previous studies concentrated less on brain network changes at a systems level. Our goal was to examine these age-related changes of fMRI-derived activation with a common network parcellation of the human brain function, offering a systems-neuroscience perspective of healthy aging. We conducted a series of meta-analyses on a total of 114 studies that included 2035 older adults and 1845 young adults. Voxels showing significant age-related changes in activation were then overlaid onto seven commonly referenced neuronal networks. Older adults present moderate cognitive decline in behavioral performance during fMRI scanning, and hypo-activate the visual network and hyper-activate both the frontoparietal control and default mode networks. The degree of increased activation in frontoparietal network was associated with behavioral performance in older adults. Age-related changes in activation present different network patterns across cognitive domains. The systems neuroscience approach used here may be useful for elucidating the underlying network mechanisms of various brain plasticity processes during healthy aging.

  10. Can induced hypothermia be assured during brain MRI in neonates with hypoxic-ischemic encephalopathy?

    Energy Technology Data Exchange (ETDEWEB)

    Wintermark, Pia [Children' s Hospital Boston, Division of Newborn Medicine, Boston, MA (United States); Children' s Hospital Boston, Department of Radiology, Boston, MA (United States); Montreal Children' s Hospital, Division of Newborn Medicine, Montreal, QC (Canada); Labrecque, Michelle; Hansen, Anne [Children' s Hospital Boston, Division of Newborn Medicine, Boston, MA (United States); Warfield, Simon K.; DeHart, Stephanie [Children' s Hospital Boston, Department of Radiology, Boston, MA (United States)

    2010-12-15

    Until now, brain MRIs in asphyxiated neonates who are receiving therapeutic hypothermia have been performed after treatment is complete. However, there is increasing interest in utilizing early brain MRI while hypothermia is still being provided to rapidly understand the degree of brain injury and possibly refine neuroprotective strategies. This study was designed to assess whether therapeutic hypothermia can be maintained while performing a brain MRI. Twenty MRI scans were obtained in 12 asphyxiated neonates while they were treated with hypothermia. The median difference between esophageal temperature on NICU departure and return was 0.1 C (range: -0.8 to 0.8 C). We found that therapeutic hypothermia can be safely and reproducibly maintained during a brain MRI. Hypothermia treatment should not prevent obtaining an early brain MRI if clinically indicated. (orig.)

  11. MRI-based brain structure volumes in temporal lobe epilepsy patients and their unaffected siblings: a preliminary study.

    LENUS (Irish Health Repository)

    Scanlon, Cathy

    2013-01-01

    Investigating the heritability of brain structure may be useful in simplifying complicated genetic studies in temporal lobe epilepsy (TLE). A preliminary study is presented to determine if volume deficits of candidate brain structures present at a higher rate in unaffected siblings than controls subjects.

  12. Mapping primary gyrogenesis during fetal development in primate brains: high-resolution in utero structural MRI study of fetal brain development in pregnant baboons

    Directory of Open Access Journals (Sweden)

    Peter Kochunov

    2010-05-01

    Full Text Available The global and regional changes in the fetal cerebral cortex in primates were mapped during primary gyrification (PG; weeks 17-25 of 26 weeks total gestation. Studying pregnant baboons using high-resolution MRI in utero, measurements included cerebral volume, cortical surface area, gyrification index and length and depth of ten primary cortical sulci. Seven normally developing fetuses were imaged in two animals longitudinally and sequentially. We compared these results to those on PG that from the ferret studies and analyzed them in the context of our recent studies of phylogenetics of cerebral gyrification. We observed that in both primates and non-primates, the cerebrum undergoes a very rapid transformation into the gyrencephalic state, subsequently accompanied by an accelerated growth in brain volume and cortical surface area. However, PG trends in baboons exhibited some critical differences from those observed in ferrets. For example, in baboons, the growth along the long (length axis of cortical sulci was unrelated to the growth along the short (depth axis and far outpaced it. Additionally, the correlation between the rate of growth along the short sulcal axis and heritability of sulcal depth was negative and approached significance (r=-0.60;p<.10, while the same trend for long axis was positive and not significant (p=0.3;p=0.40. These findings, in an animal that shares a highly orchestrated pattern of PG with humans, suggest that ontogenic processes that influence changes in sulcal length and depth are diverse and possibly driven by different factors in primates than in non-primates.

  13. Combined MRI and MRS improves pre-therapeutic diagnoses of pediatric brain tumors over MRI alone

    Energy Technology Data Exchange (ETDEWEB)

    Shiroishi, Mark S.; Nelson, Marvin D. [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Panigrahy, Ashok [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Department of Pediatric Radiology, Pittsburgh, PA (United States); Moore, Kevin R. [Primary Children' s Medical Center, Department of Radiology, Salt Lake City, UT (United States); Gilles, Floyd H. [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Pathology, Los Angeles, CA (United States); Gonzalez-Gomez, Ignacio [All Children' s Hospital, Department of Pathology, St. Petersburg, FL (United States); Blueml, Stefan [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Rudi Schulte Research Institute, Santa Barbara, CA (United States)

    2015-09-15

    The specific goal of this study was to determine whether the inclusion of MRS had a measureable and positive impact on the accuracy of pre-surgical MR examinations of untreated pediatric brain tumors over that of MRI alone in clinical practice. Final imaging reports of 120 pediatric patients with newly detected brain tumors who underwent combined MRI/MRS examinations were retrospectively reviewed. Final pathology was available in all cases. Group A comprised 60 subjects studied between June 2001 and January 2005, when MRS was considered exploratory and radiologists utilized only conventional MRI to arrive at a diagnosis. For group B, comprising 60 subjects studied between January 2005 and March 2008, the radiologists utilized information from both MRI and MRS. Furthermore, radiologists revisited group A (blind review, time lapse >4 years) to determine whether the additional information from MRS would have altered their interpretation. Sixty-three percent of patients in group A were diagnosed correctly, whereas in 10 % the report was partially correct with the final tumor type mentioned (but not mentioned as most likely tumor), while in 27 % of cases the reports were wrong. For group B, the diagnoses were correct in 87 %, partially correct in 5 %, and incorrect in 8 % of the cases, which is a significant improvement (p < 0.005). Re-review of combined MRI and MRS of group A resulted 87 % correct, 7 % partially correct, and 7 % incorrect diagnoses, which is a significant improvement over the original diagnoses (p < 0.05). Adding MRS to conventional MRI significantly improved diagnostic accuracy in preoperative pediatric patients with untreated brain tumors. (orig.)

  14. Sleep Apnea, Sleep Duration and Brain MRI Markers of Cerebral Vascular Disease and Alzheimer's Disease: The Atherosclerosis Risk in Communities Study (ARIC.

    Directory of Open Access Journals (Sweden)

    Pamela L Lutsey

    Full Text Available A growing body of literature has suggested that obstructive sleep apnea (OSA and habitual short sleep duration are linked to poor cognitive function. Neuroimaging studies may provide insight into this relation.We tested the hypotheses that OSA and habitual short sleep duration, measured at ages 54-73 years, would be associated with adverse brain morphology at ages 67-89 years.Included in this analysis are 312 ARIC study participants who underwent in-home overnight polysomnography in 1996-1998 and brain MRI scans about 15 years later (2012-2013. Sleep apnea was quantified by the apnea-hypopnea index and categorized as moderate/severe (≥15.0 events/hour, mild (5.0-14.9 events/hour, or normal (<5.0 events/hour. Habitual sleep duration was categorized, in hours, as <7, 7 to <8, ≥8. MRI outcomes included number of infarcts (total, subcortical, and cortical and white matter hyperintensity (WMH and Alzheimer's disease signature region volumes. Multivariable adjusted logistic and linear regression models were used. All models incorporated inverse probability weighting, to adjust for potential selection bias.At the time of the sleep study participants were 61.7 (SD: 5.0 years old and 54% female; 19% had moderate/severe sleep apnea. MRI imaging took place 14.8 (SD: 1.0 years later, when participants were 76.5 (SD: 5.2 years old. In multivariable models which accounted for body mass index, neither OSA nor abnormal sleep duration were statistically significantly associated with odds of cerebral infarcts, WMH brain volumes or regional brain volumes.In this community-based sample, mid-life OSA and habitually short sleep duration were not associated with later-life cerebral markers of vascular dementia and Alzheimer's disease. However, selection bias may have influenced our results and the modest sample size led to relatively imprecise associations.

  15. MRI Brain Image Segmentation based on Thresholding

    Directory of Open Access Journals (Sweden)

    G. Evelin Sujji, Y.V.S. Lakshmi, G. Wiselin Jiji

    2013-03-01

    Full Text Available Medical Image processing is one of the mostchallenging topics in research field. The mainobjective of image segmentation is to extract variousfeatures of the image that are used foranalysing,interpretation and understanding of images.Medical Resonance Image plays a major role inMedical diagnostics. Image processing in MRI ofbrain is highlyessential due to accurate detection ofthe type of brain abnormality which can reduce thechance of fatal result. This paper outlines anefficient image segmentation technique that candistinguish the pathological tissues such asedemaandtumourfrom thenormal tissues such as WhiteMatter(WM,GreyMatter(GM, andCerebrospinal Fluid(CSF. Thresholding is simplerand most commonly used techniques in imagesegmentation. This technique can be used to detectthe contour of thetumourin brain.

  16. MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain.

    Science.gov (United States)

    Eide, Per Kristian; Ringstad, Geir

    2015-11-01

    Recently, the "glymphatic system" of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study glymphatic function in the human brain.

  17. Brain effects of computer-assisted cognitive remediation therapy in anorexia nervosa: A pilot fMRI study.

    Science.gov (United States)

    Brockmeyer, Timo; Walther, Stephan; Ingenerf, Katrin; Wild, Beate; Hartmann, Mechthild; Weisbrod, Matthias; Weber, Marc-André; Eckhardt-Henn, Annegret; Herzog, Wolfgang; Friederich, Hans-Christoph

    2016-03-30

    Poor cognitive-behavioral flexibility is considered a trait marker in anorexia nervosa (AN) that can be improved by cognitive remediation therapy (CRT). The present pilot study aimed at identifying changes in brain function potentially associated with CRT in AN. Data was obtained from a randomized, controlled trial. Twenty-four patients were assessed before and after 30 sessions of either CRT or a non-specific neurocognitive therapy. Voxel-wise analysis of whole brain functional magnetic resonance imaging was applied. Brain activation was measured during response inhibition and task switching. Although results did not reach significance, we found tentative support for CRT-related increases in brain activation in the dorsal putamen during task switching and in the dorsolateral prefrontal, sensorimotor and temporal cortex during response inhibition. These pilot findings provide viable pathways for future research on brain changes underlying CRT in AN.

  18. Genetic correlates of brain aging on MRI and cognitive test measures: a genome-wide association and linkage analysis in the Framingham study

    OpenAIRE

    2007-01-01

    Abstract Background Brain magnetic resonance imaging (MRI) and cognitive tests can identify heritable endophenotypes associated with an increased risk of developing stroke, dementia and Alzheimer's disease (AD). We conducted a genome-wide association (GWA) and linkage analysis exploring the genetic basis of these endophenotypes in a community-based sample. Methods A total of 705 stroke- and dementia-free Framingham participants (age 62 +9 yrs, 50% male) who underwent volumetric brain MRI and ...

  19. Pathological and incidental findings on brain MRI in a single-center study of 229 consecutive girls with early or precocious puberty

    DEFF Research Database (Denmark)

    Mogensen, Signe Sloth; Aksglaede, Lise; Mouritsen, Annette;

    2012-01-01

    Central precocious puberty may result from organic brain lesions, but is most frequently of idiopathic origin. Clinical or biochemical factors which could predict a pathological brain MRI in girls with CPP have been searched for. With the recent decline in age at pubertal onset among US and Europ......Central precocious puberty may result from organic brain lesions, but is most frequently of idiopathic origin. Clinical or biochemical factors which could predict a pathological brain MRI in girls with CPP have been searched for. With the recent decline in age at pubertal onset among US...

  20. Imaging brain neuronal activity using functionalized magnetonanoparticles and MRI.

    Science.gov (United States)

    Akhtari, Massoud; Bragin, Anatol; Moats, Rex; Frew, Andrew; Mandelkern, Mark

    2012-10-01

    This study explored the use of non-radioactive 2-deoxy glucose (2DG)-labeled magnetonanoparticles (MNP) and magnetic resonance imaging (MRI) to detect functional activity during rest, peripheral stimulation, and epileptic seizures, in animal models. Non-radioactive 2DG was covalently attached to magnetonanoparticles composed of iron oxide and dextran and intravenous (tail) injections were performed. 2DG-MNP was injected in resting and stimulated naïve rodents and the subsequent MRI was compared to published (14)C-2DG autoradiography data. Reproducibility and statistical significance was established in one studied model. Negative contrast enhancement (NCE) in acute seizures and chronic models of epilepsy were investigated. MRI NCE due to 2DG-MNP particles was compared to that of plain (unconjugated) MNP in one animal. NCE due to 2DG-MNP particles at 3 T, which is approved for human use, was also investigated. Histology showed presence of MNP (following intravenous injection) in the brain tissues of resting naïve animal. 2DG-MNP intraparenchymal uptake was visible on MRI and histology. The locations of NCE agreed with published results of 2DG autoradiography in resting and stimulated animals and epileptic rats. Localization of epileptogenicity was confirmed by subsequent depth-electrode EEG (iEEG). Non-radioactive 2DG-MNP can cross the blood-brain barrier (BBB) and may accurately localize areas of increased activity. Although, this proof-of-principle study involves only a limited number of animals, and much more research and quantification are necessary to demonstrate that 2DG-MNP, or MNPs conjugated with other ligands, could eventually be used to image localized cerebral function with MRI in humans, this MNP-MRI approach is potentially applicable to the use of many bioactive molecules as ligands for imaging normal and abnormal localized cerebral functions.

  1. A single session of exercise increases connectivity in sensorimotor-related brain networks: A resting-state fMRI study in young healthy adults

    Directory of Open Access Journals (Sweden)

    Ahmad Saeed Rajab

    2014-08-01

    Full Text Available Habitual long term physical activity is known to have beneficial cognitive, structural and neuro-protective brain effects, but to date there is limited knowledge on whether a single session of exercise can alter the brain’s functional connectivity, as assessed by resting-state fMRI (rs-fMRI. The primary objective of this study was to characterize potential session effects in resting state networks (RSNs. We examined the acute effects of exercise on the functional connectivity of young healthy adults (N=15 by collecting rs-fMRI before and after 20 minutes of moderate intensity aerobic exercise and compared this with a no-exercise control group (N=15. Data were analysed using independent component analysis, denoising and dual regression procedures. ROI-based group session effect statistics were calculated in RSNs of interest using voxel-wise permutation testing and Cohen’s D effect size. Group analysis in the exercising group data set revealed a session effect in sub-regions of three sensorimotor related areas: the pre and/or postcentral gyri, secondary somatosensory area and thalamus, characterized by increased co-activation after exercise (corrected p<0.05. Cohen’s D analysis also showed a significant effect of session in these three RSNs (p<0.05, corroborating the voxel-wise findings. Analyses of the no-exercise dataset produced no significant results, thereby providing support for the exercise findings and establishing the inherent test-retest reliability of the analysis pipeline on the RSNs of interest. This study establishes the feasibility of rs-fMRI to localize brain regions that are associated with acute exercise, as well as an analysis consideration to improve sensitivity to a session effect.

  2. Differences in Brain Hemodynamics in Response to Achromatic and Chromatic Cards of the Rorschach: A fMRI Study.

    Science.gov (United States)

    Ishibashi, Masahiro; Uchiumi, Chigusa; Jung, Minyoung; Aizawa, Naoki; Makita, Kiyoshi; Nakamura, Yugo; Saito, Daisuke N

    2016-01-01

    In order to investigate the effects of color stimuli of the Rorschach inkblot method (RIM), the cerebral activity of 40 participants with no history of neurological or psychiatric illness was scanned while they engaged in the Rorschach task. A scanned image of the ten RIM inkblots was projected onto a screen in the MRI scanner. Cerebral activation in response to five achromatic color cards and five chromatic cards were compared. As a result, a significant increase in brain activity was observed in bilateral visual areas V2 and V3, parietooccipital junctions, pulvinars, right superior temporal gyrus, and left premotor cortex for achromatic color cards (p < .001). For the cards with chromatic color, significant increase in brain activity was observed in left visual area V4 and left orbitofrontal cortex (p < .001). Furthermore, a conjoint analysis revealed various regions were activated in responding to the RIM. The neuropsychological underpinnings of the response process, as described by Acklin and Wu-Holt (1996), were largely confirmed.

  3. Changes in brain activation patterns according to cross-training effect in serial reaction time task An functional MRI study

    Institute of Scientific and Technical Information of China (English)

    Yong Hyun Kwon; Jung Won Kwon; Ji Won Park

    2013-01-01

    Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral limb. We used functional MRI to investigate whether motor performance of the untrained limb could be improved using a serial reaction time task according to motor sequential learning of the trained limb, and whether these skill acquisitions led to changes in brain activation patterns. We recruited 20 right-handed healthy subjects, who were randomly allocated into training and control groups. The training group was trained in performance of a serial reaction time task using their non-dominant left hand, 40 minutes per day, for 10 days, over a period of 2 weeks. The control group did not receive training. Measurements of response time and percentile of response accuracy were performed twice during pre- and post-training, while brain functional MRI was scanned during performance of the serial reaction time task using the untrained right hand. In the training group, prominent changes in response time and percentile of response accuracy were observed in both the untrained right hand and the trained left hand between pre- and post-training. The control group showed no significant changes in the untrained hand between pre- and post-training. In the training group, the activated volume of the cortical areas related to motor function (i.e., primary motor cortex, premotor area, posterior parietal cortex) showed a gradual decrease, and enhanced cerebellar activation of the vermis and the newly activated ipsilateral dentate nucleus were observed during performance of the serial reaction time task using the untrained right hand, accompanied by the cross-motor learning effect. However, no significant changes were observed in the control group. Our findings indicate that motor skills learned over the 2-week training using the trained limb were transferred to the

  4. Chediak-Higashi syndrome: brain MRI and MR spectroscopy manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Lolli, Valentina; Soto Ares, Gustavo; Pruvo, Jean-Pierre [Roger Salengro Hospital, CHRU, Neuroradiology Department, Lille (France); Abou Chahla, Wadih [Jeanne de Flandre Hospital, Pediatric Hematology and Oncology Department, Lille (France); Jissendi-Tchofo, Patrice [University Hospital Saint-Pierre, Radiology Department - Pediatric Neuroradiology Section, Brussels (Belgium)

    2015-08-15

    Chediak-Higashi syndrome is a rare inherited metabolic disorder characterized by partial oculocutaneous albinism, immunodeficiency, and neurological dysfunction. We present the brain magnetic resonance imaging (MRI) and MR spectroscopy (MRS) findings obtained during the accelerated phase of the disorder in an 8-year-old. The brain MRI manifestations at recurrences 15 months and 24 months later are reported as well. (orig.)

  5. Increased frequency of brain pathology in inmates of a high-security forensic institution: a qualitative CT and MRI scan study.

    Science.gov (United States)

    Witzel, Joachim G; Bogerts, Bernhard; Schiltz, Kolja

    2016-09-01

    This study aimed to assess whether brain pathology might be more abundant in forensic inpatients in a high-security setting than in non-criminal individuals. By using a previously used reliable approach, we explored the frequency and extent of brain pathology in a large group of institutionalized offenders who had not previously been considered to be suffering from structural brain damage and compare it to healthy, non-offending subjects. MRI and CT brain scans from 148 male inpatients of a high-security mental health institution (offense type: 51 sex, 80 violent, 9 arson, and 8 nonviolent) that were obtained due to headache, vertigo, or psychological complaints during imprisonment were assessed and compared to 52 non-criminal healthy controls. Brain scans were assessed qualitatively with respect to evidence of structural brain damage. Each case received a semiquantitative rating of "normal" (=0), "questionably abnormal" (=1), or "definitely abnormal" (=2) for the lateral ventricles, frontal/parietal cortex, and medial temporal structures bilaterally as well as third ventricle. Forensic inpatients displayed signs of brain damage to a significantly higher degree than healthy controls (p pathology. The astonishingly high prevalence of brain pathology in institutionalized inmates of a high-security mental health institution who previously had not been considered to be suffering from an organic brain syndrome raises questions on whether such neuroradiological assessment might be considered as a routine procedure in newly admitted patients. Furthermore, it highlights that organic changes, detectable under clinical routine conditions, may play a role in the development of legally relevant behavioral disturbances which might be underestimated.

  6. Dynamics of cerebral edema and the apparent diffusion coefficient of water changes in patients with severe traumatic brain injury. A prospective MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Pasco, Anne [Larrey Hospital, Angers University, Department of Radiology, Cedex (France); Inserm, Angers (France); Angers University, Angers (France); Minassian, Aram Ter [Larrey Hospital, Angers University, Department of Anaesthesiology, Cedex (France); Chapon, Catherine; Lemaire, Laurent; Benoit, Jean-Pierre; Jeune, Jean-Jacques Le [Inserm, Angers (France); Angers University, Angers (France); Franconi, Florence [Angers University, SCAS, Angers (France); Darabi, Dana; Caron, Christine [Larrey Hospital, Angers University, Department of Radiology, Cedex (France)

    2006-07-15

    The distinction between intracellular (ICE) and extracellular edema (ECE) has a crucial prognostic and therapeutic importance in patients with severe traumatic brain injury (STBI). Indeed, ICE usually leads to cellular death, and maintenance of a cerebral perfusion pressure (CPP) above 70 mmHg is still under debate since this practice may increase ECE. The purpose of this study was to describe the ECE and ICE kinetics associated with STBI using quantitative diffusion MRI. Twelve patients were prospectively studied. The initial ADC in ICE measured on day 1.3{+-}0.7 is significantly reduced compared to normal-appearing parenchyma (0.51{+-}0.12 * 10{sup -3} mm{sup 2}/s vs. 0.76{+-}0.03 * 10{sup -3} mm{sup 2}/s, n=12, P<0.0001) and reaches normality on MRI 3 performed on day 14.2{+-}3.3. In patients presenting an extension of ICE on MRI 2 performed on day 6.7{+-}1.4 (ADC{sub MRI2}=0.40{+-}0.11 * 10{sup -3} mm{sup 2}/s), ADC values in the extension area at the first MRI were slightly, but not significantly reduced compared to normal parenchyma (0.69{+-}0.05 * 10{sup -3} mm{sup 2}/s, P=0.29). Normalization occurred equally by day 14. ADC in ECE (1.34{+-}0.22 * 10{sup -3} mm{sup 2}/s) was elevated and stable with time under CPP therapy. Therefore, ECE is not worsened by CCP therapy, and ICE appears more relevant than ECE in STBI. (orig.)

  7. MRI Brain Activation During Instruction of Dyslexic Children

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2003-08-01

    Full Text Available Ten children with dyslexia and 11 normal readers performed tasks of phoneme mapping (assigning sounds to letters and morpheme mapping (relating suffixed words to their roots during fMRI scanning, before and after 28 hours of comprehensive reading instruction, in a study of the effects of reading instruction on brain activation in children with dyslexia at University of Washington, Seattle, WA.

  8. Effects of different correlation metrics and preprocessing factors on small-world brain functional networks: a resting-state functional MRI study.

    Directory of Open Access Journals (Sweden)

    Xia Liang

    Full Text Available Graph theoretical analysis of brain networks based on resting-state functional MRI (R-fMRI has attracted a great deal of attention in recent years. These analyses often involve the selection of correlation metrics and specific preprocessing steps. However, the influence of these factors on the topological properties of functional brain networks has not been systematically examined. Here, we investigated the influences of correlation metric choice (Pearson's correlation versus partial correlation, global signal presence (regressed or not and frequency band selection [slow-5 (0.01-0.027 Hz versus slow-4 (0.027-0.073 Hz] on the topological properties of both binary and weighted brain networks derived from them, and we employed test-retest (TRT analyses for further guidance on how to choose the "best" network modeling strategy from the reliability perspective. Our results show significant differences in global network metrics associated with both correlation metrics and global signals. Analysis of nodal degree revealed differing hub distributions for brain networks derived from Pearson's correlation versus partial correlation. TRT analysis revealed that the reliability of both global and local topological properties are modulated by correlation metrics and the global signal, with the highest reliability observed for Pearson's-correlation-based brain networks without global signal removal (WOGR-PEAR. The nodal reliability exhibited a spatially heterogeneous distribution wherein regions in association and limbic/paralimbic cortices showed moderate TRT reliability in Pearson's-correlation-based brain networks. Moreover, we found that there were significant frequency-related differences in topological properties of WOGR-PEAR networks, and brain networks derived in the 0.027-0.073 Hz band exhibited greater reliability than those in the 0.01-0.027 Hz band. Taken together, our results provide direct evidence regarding the influences of correlation metrics

  9. MRI of brain disease in veterinary patients part 1: Basic principles and congenital brain disorders.

    Science.gov (United States)

    Hecht, Silke; Adams, William H

    2010-01-01

    Magnetic resonance imaging (MRI) is increasingly being used in the diagnosis of central nervous system disorders in veterinary patients and is quickly becoming the imaging modality of choice in evaluation of brain and intracranial disease. This article provides an overview of the basic principles of MRI, a description of sequences and their applications in brain imaging, and an approach to interpretation of brain MRI. A detailed discussion of imaging findings in general intracranial disorders including hydrocephalus, vasogenic edema, brain herniation, and seizure-associated changes, and the MR diagnosis of congenital brain disorders is provided. MRI evaluation of acquired brain disorders is described in a second companion article.

  10. Semiautomatic segmentation and follow-up of multicomponent low-grade tumors in longitudinal brain MRI studies

    Energy Technology Data Exchange (ETDEWEB)

    Weizman, Lior, E-mail: weizmanl@gmail.com [School of Engineering and Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Sira, Liat Ben [Department of Radiology, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv 64239 (Israel); Joskowicz, Leo [School of Engineering and Computer Science and The Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); Rubin, Daniel L.; Yeom, Kristen W. [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Constantini, Shlomi; Shofty, Ben [Tel Aviv Medical Center, Dana Children' s Hospital, Tel Aviv University, Tel Aviv 64239 (Israel); Bashat, Dafna Ben [Tel Aviv Medical Center, Functional Brain Center, Tel Aviv University, Tel Aviv 64239 (Israel)

    2014-05-15

    Purpose: Tracking the progression of low grade tumors (LGTs) is a challenging task, due to their slow growth rate and associated complex internal tumor components, such as heterogeneous enhancement, hemorrhage, and cysts. In this paper, the authors show a semiautomatic method to reliably track the volume of LGTs and the evolution of their internal components in longitudinal MRI scans. Methods: The authors' method utilizes a spatiotemporal evolution modeling of the tumor and its internal components. Tumor components gray level parameters are estimated from the follow-up scan itself, obviating temporal normalization of gray levels. The tumor delineation procedure effectively incorporates internal classification of the baseline scan in the time-series as prior data to segment and classify a series of follow-up scans. The authors applied their method to 40 MRI scans of ten patients, acquired at two different institutions. Two types of LGTs were included: Optic pathway gliomas and thalamic astrocytomas. For each scan, a “gold standard” was obtained manually by experienced radiologists. The method is evaluated versus the gold standard with three measures: gross total volume error, total surface distance, and reliability of tracking tumor components evolution. Results: Compared to the gold standard the authors' method exhibits a mean Dice similarity volumetric measure of 86.58% and a mean surface distance error of 0.25 mm. In terms of its reliability in tracking the evolution of the internal components, the method exhibits strong positive correlation with the gold standard. Conclusions: The authors' method provides accurate and repeatable delineation of the tumor and its internal components, which is essential for therapy assessment of LGTs. Reliable tracking of internal tumor components over time is novel and potentially will be useful to streamline and improve follow-up of brain tumors, with indolent growth and behavior.

  11. Age, gender, and hemispheric differences in iron deposition in the human brain: an in vivo MRI study.

    Science.gov (United States)

    Xu, Xiaojun; Wang, Qidong; Zhang, Minming

    2008-03-01

    It is well known that iron accumulates in the brains of patients with various neurodegenerative diseases. To better understand disease-related iron changes, it is necessary to know the physiological distribution and accumulation of iron in the human brain. Studies have shown that brain iron levels increase with aging. However, the effects of gender and hemispheric laterality on iron accumulation and distribution are not well established. In this study, we estimated the brain iron levels in vivo in 78 healthy adults ranging in age 22 to 78 years using magnetic susceptibility-weighted phase imaging. The effects of age, gender, and hemispheric location on brain iron levels were evaluated within the framework of a general linear model. We found that the left hemisphere had higher iron levels than the right in the putamen, globus pallidus, substantia nigra, thalamus, and frontal white matter. We argue that the hemispheric asymmetry of iron content may underlie that of the dopaminergic system and may be related to motor lateralization in humans. In addition, significant age-related iron accumulation occurred in the putamen, red nucleus, and frontal white matter, but no gender-related differences in iron levels were detected. The results of this study extend our knowledge of the physiological distribution and accumulation of iron in the human brain.

  12. Functional MRI of the brain: localisation of eloquent cortex in focal brain lesion therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dymarkowski, S.; Sunaert, S.; Oostende, S. van; Hecke, P. van; Wilms, G.; Demaerel, P.; Marchal, G. [Department of Radiology, University Hospitals, Leuven (Belgium); Nuttin, B.; Plets, C. [Department of Neurosurgery, University Hospitals, Leuven (Belgium)

    1998-12-01

    The aim of this study was to assess the feasibility of functional MRI (fMRI) in a clinical environment on a large patient group, and to evaluate the pretherapeutic value of localisation of eloquent cortex. Forty patients with focal brain lesions of different origin were studied using fMRI. Functional information was obtained using motor, somatosensory, auditory and phonological stimuli depending on the localisation of the lesions. To obtain information about the spatial accuracy of fMRI, the results were compared with postoperative electrocortical stimulation. Two patients with secondary trigeminal neuralgia were scanned using a motor protocol and were implanted with an extradural plate electrode. Imaging was successful in 40 of 42 patients (including the 2 with trigeminal neuralgia). These patients were analysed for strength of activation, the relation of the lesion to activation sites and the presence of mass effect. The correlation between these data and surgical findings provided significant additional clinical information. Functional MRI can be accurately performed in patients with focal brain lesions using a dedicated approach. Functional MRI offers important clinical information as a contribution to a decrease in posttherapeutic morbidity. The accuracy of the technique can be confirmed by other modalities, including invasive cortical electrostimulation. (orig.) With 7 figs., 2 tabs., 25 refs.

  13. MRI of 'brain death'

    Energy Technology Data Exchange (ETDEWEB)

    Nishino, Shigeki; Itoh, Takahiko; Tuchida, Shohei; Kinugasa, Kazushi; Asari, Shoji; Nishimoto, Akira (Okayama Univ. (Japan). School of Medicine); Sanou, Kazuo

    1990-12-01

    Magnetic resonance imaging (MRI) was undertaken for two patients who suffered from severe cerebrovascular diseases and were clinically brain dead. The MRI system we used was Resona (Yokogawa Medical Systems, superconductive system 0.5 T) and the CT apparatus was Toshiba TCT-300. Initial CT and MRI were undertaken as soon as possible after admission, and repeated sequentially. After diagnosis of brain death, we performed angiography to determine cerebral circulatory arrest, and MRI obtained at the same time was compared with the angiogram and CT. Case 1 was a 77-year-old man who was admitted in an unconscious state. CT and MRI on the second day after hospitalization revealed cerebellar infarction. He was diagnosed as brain dead on day 4. Case 2 was a 35-year-old man. When he was transferred to our hospital, he was in cardiorespiratory arrested. Cardiac resuscitation was successful but no spontaneous respiration appeared. CT and MRI on admission revealed right intracerebral hemorrhage. Angiography revealed cessation of contrast medium in intracranial vessels in both of the patients. We found no 'flow signal void sign' in the bilateral internal carotid and basilar arteries on MRI images in both cases after brain death. MRI, showing us the anatomical changes of the brain, clearly revealed brain herniations, even though only nuclear findings of 'brain tamponade' were seen on CT. But in Case 1, we could not see the infarct lesions in the cerebellum on MR images obtained after brain death. This phenomenon was caused by the whole brain ischemia masking the initial ischemic lesions. We concluded that MRI was useful not only the anatomical display of lesions and brain herniation with high contrast resolution but for obtaining information on cerebral circulation of brain death. (author).

  14. Imaging tools to study pharmacology: functional MRI on small rodents

    Directory of Open Access Journals (Sweden)

    Elisabeth eJonckers

    2015-10-01

    Full Text Available Functional Magnetic Resonance Imaging (fMRI is an excellent tool to study the effect of pharmacological modulations on brain function in a non-invasive and longitudinal manner. We introduce several blood oxygenation level dependent (BOLD fMRI techniques, including resting state (rsfMRI, stimulus-evoked (st-fMRI, and pharmacological MRI (phMRI. Respectively, these techniques permit the assessment of functional connectivity during rest as well as brain activation triggered by sensory stimulation and/or a pharmacological challenge. The first part of this review describes the physiological basis of BOLD fMRI and the hemodynamic response on which the MRI contrast is based. Specific emphasis goes to possible effects of anaesthesia and the animal’s physiological conditions on neural activity and the hemodynamic response. The second part of this review describes applications of the aforementioned techniques in pharmacologically-induced, as well as in traumatic and transgenic disease models and illustrates how multiple fMRI methods can be applied successfully to evaluate different aspects of a specific disorder. For example, fMRI techniques can be used to pinpoint the neural substrate of a disease beyond previously defined hypothesis-driven regions-of-interest (ROIs. In addition, fMRI techniques allow one to dissect how specific modifications (e.g. treatment, lesion etc. modulate the functioning of specific brain areas (st-fMRI, phMRI and how functional connectivity (rsfMRI between several brain regions is affected, both in acute and extended time frames. Furthermore, fMRI techniques can be used to assess/explore the efficacy of novel treatments in depth, both in fundamental research as well as in preclinical settings. In conclusion, by describing several exemplary studies, we aim to highlight the advantages of functional MRI in exploring the acute and long-term effects of pharmacological substances and/or pathology on brain functioning along with

  15. Permeability dependence study of the focused ultrasound-induced blood-brain barrier opening at distinct pressures and microbubble diameters using DCE-MRI.

    Science.gov (United States)

    Vlachos, Fotios; Tung, Yao-Sheng; Konofagou, Elisa

    2011-09-01

    Blood-brain barrier opening using focused ultrasound and microbubbles has been experimentally established as a noninvasive and localized brain drug delivery technique. In this study, the permeability of the opening is assessed in the murine hippocampus after the application of focused ultrasound at three different acoustic pressures and microbubble sizes. Using dynamic contrast-enhanced MRI, the transfer rates were estimated, yielding permeability maps and quantitative K(trans) values for a predefined region of interest. The volume of blood-brain barrier opening according to the K(trans) maps was proportional to both the pressure and the microbubble diameter. A K(trans) plateau of ∼0.05 min(-1) was reached at higher pressures (0.45 and 0.60 MPa) for the larger sized bubbles (4-5 and 6-8 μm), which was on the same order as the K(trans) of the epicranial muscle (no barrier). Smaller bubbles (1-2 μm) yielded significantly lower permeability values. A small percentage (7.5%) of mice showed signs of damage under histological examination, but no correlation with permeability was established. The assessment of the blood-brain barrier permeability properties and their dependence on both the pressure and the microbubble diameter suggests that K(trans) maps may constitute an in vivo tool for the quantification of the efficacy of the focused ultrasound-induced blood-brain barrier opening.

  16. Meta-analysis of real-time fMRI neurofeedback studies using individual participant data: How is brain regulation mediated?

    Science.gov (United States)

    Emmert, Kirsten; Kopel, Rotem; Sulzer, James; Brühl, Annette B; Berman, Brian D; Linden, David E J; Horovitz, Silvina G; Breimhorst, Markus; Caria, Andrea; Frank, Sabine; Johnston, Stephen; Long, Zhiying; Paret, Christian; Robineau, Fabien; Veit, Ralf; Bartsch, Andreas; Beckmann, Christian F; Van De Ville, Dimitri; Haller, Sven

    2016-01-01

    An increasing number of studies using real-time fMRI neurofeedback have demonstrated that successful regulation of neural activity is possible in various brain regions. Since these studies focused on the regulated region(s), little is known about the target-independent mechanisms associated with neurofeedback-guided control of brain activation, i.e. the regulating network. While the specificity of the activation during self-regulation is an important factor, no study has effectively determined the network involved in self-regulation in general. In an effort to detect regions that are responsible for the act of brain regulation, we performed a post-hoc analysis of data involving different target regions based on studies from different research groups. We included twelve suitable studies that examined nine different target regions amounting to a total of 175 subjects and 899 neurofeedback runs. Data analysis included a standard first- (single subject, extracting main paradigm) and second-level (single subject, all runs) general linear model (GLM) analysis of all participants taking into account the individual timing. Subsequently, at the third level, a random effects model GLM included all subjects of all studies, resulting in an overall mixed effects model. Since four of the twelve studies had a reduced field of view (FoV), we repeated the same analysis in a subsample of eight studies that had a well-overlapping FoV to obtain a more global picture of self-regulation. The GLM analysis revealed that the anterior insula as well as the basal ganglia, notably the striatum, were consistently active during the regulation of brain activation across the studies. The anterior insula has been implicated in interoceptive awareness of the body and cognitive control. Basal ganglia are involved in procedural learning, visuomotor integration and other higher cognitive processes including motivation. The larger FoV analysis yielded additional activations in the anterior cingulate

  17. Validation of MRI-based 3D digital atlas registration with histological and autoradiographic volumes: an anatomofunctional transgenic mouse brain imaging study.

    Science.gov (United States)

    Lebenberg, J; Hérard, A-S; Dubois, A; Dauguet, J; Frouin, V; Dhenain, M; Hantraye, P; Delzescaux, T

    2010-07-01

    Murine models are commonly used in neuroscience to improve our knowledge of disease processes and to test drug effects. To accurately study neuroanatomy and brain function in small animals, histological staining and ex vivo autoradiography remain the gold standards to date. These analyses are classically performed by manually tracing regions of interest, which is time-consuming. For this reason, only a few 2D tissue sections are usually processed, resulting in a loss of information. We therefore proposed to match a 3D digital atlas with previously 3D-reconstructed post mortem data to automatically evaluate morphology and function in mouse brain structures. We used a freely available MRI-based 3D digital atlas derived from C57Bl/6J mouse brain scans (9.4T). The histological and autoradiographic volumes used were obtained from a preliminary study in APP(SL)/PS1(M146L) transgenic mice, models of Alzheimer's disease, and their control littermates (PS1(M146L)). We first deformed the original 3D MR images to match our experimental volumes. We then applied deformation parameters to warp the 3D digital atlas to match the data to be studied. The reliability of our method was qualitatively and quantitatively assessed by comparing atlas-based and manual segmentations in 3D. Our approach yields faster and more robust results than standard methods in the investigation of post mortem mouse data sets at the level of brain structures. It also constitutes an original method for the validation of an MRI-based atlas using histology and autoradiography as anatomical and functional references, respectively.

  18. Real-time fMRI brain computer interfaces: self-regulation of single brain regions to networks.

    Science.gov (United States)

    Ruiz, Sergio; Buyukturkoglu, Korhan; Rana, Mohit; Birbaumer, Niels; Sitaram, Ranganatha

    2014-01-01

    With the advent of brain computer interfaces based on real-time fMRI (rtfMRI-BCI), the possibility of performing neurofeedback based on brain hemodynamics has become a reality. In the early stage of the development of this field, studies have focused on the volitional control of activity in circumscribed brain regions. However, based on the understanding that the brain functions by coordinated activity of spatially distributed regions, there have recently been further developments to incorporate real-time feedback of functional connectivity and spatio-temporal patterns of brain activity. The present article reviews the principles of rtfMRI neurofeedback, its applications, benefits and limitations. A special emphasis is given to the discussion of novel developments that have enabled the use of this methodology to achieve self-regulation of the functional connectivity between different brain areas and of distributed brain networks, anticipating new and exciting applications for cognitive neuroscience and for the potential alleviation of neuropsychiatric disorders.

  19. Automated detection of multiple sclerosis lesions in serial brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Llado, Xavier; Ganiler, Onur; Oliver, Arnau; Marti, Robert; Freixenet, Jordi [University of Girona, Computer Vision and Robotics Group, Girona (Spain); Valls, Laia [Dr. Josep Trueta University Hospital, Department of Radiology, Girona (Spain); Vilanova, Joan C. [Girona Magnetic Resonance Center, Girona (Spain); Ramio-Torrenta, Lluis [Dr. Josep Trueta University Hospital, Institut d' Investigacio Biomedica de Girona, Multiple Sclerosis and Neuroimmunology Unit, Girona (Spain); Rovira, Alex [Vall d' Hebron University Hospital, Magnetic Resonance Unit, Department of Radiology, Barcelona (Spain)

    2012-08-15

    Multiple sclerosis (MS) is a serious disease typically occurring in the brain whose diagnosis and efficacy of treatment monitoring are vital. Magnetic resonance imaging (MRI) is frequently used in serial brain imaging due to the rich and detailed information provided. Time-series analysis of images is widely used for MS diagnosis and patient follow-up. However, conventional manual methods are time-consuming, subjective, and error-prone. Thus, the development of automated techniques for the detection and quantification of MS lesions is a major challenge. This paper presents an up-to-date review of the approaches which deal with the time-series analysis of brain MRI for detecting active MS lesions and quantifying lesion load change. We provide a comprehensive reference source for researchers in which several approaches to change detection and quantification of MS lesions are investigated and classified. We also analyze the results provided by the approaches, discuss open problems, and point out possible future trends. Lesion detection approaches are required for the detection of static lesions and for diagnostic purposes, while either quantification of detected lesions or change detection algorithms are needed to follow up MS patients. However, there is not yet a single approach that can emerge as a standard for the clinical practice, automatically providing an accurate MS lesion evolution quantification. Future trends will focus on combining the lesion detection in single studies with the analysis of the change detection in serial MRI. (orig.)

  20. Mapping brain morphological and functional conversion patterns in amnestic MCI: a voxel-based MRI and FDG-PET study

    Energy Technology Data Exchange (ETDEWEB)

    Morbelli, Silvia [University of Genoa, Nuclear Medicine Unit, Department of Internal Medicine, Genoa (Italy); Piccardo, Arnoldo; Villavecchia, Giampiero [Galliera Hospital, Nuclear Medicine Unit, Department of Radiology, Genoa (Italy); Dessi, Barbara; Brugnolo, Andrea; Rodriguez, Guido; Nobili, Flavio [University of Genoa, Clinical Neurophysiology Unit, Department of Neurosciences, Ophthalmology and Genetics, Genoa (Italy); Piccini, Alessandra [Cell Biology Unit, National Cancer Research Institute, Genoa (Italy); Caroli, Anna [LENITEM - Laboratory of Epidemiology Neuroimaging and Telemedicine, Brescia (Italy); Mario Negri Institute, Medical Imaging Unit, Biomedical Engineering Department, Bergamo (Italy); Frisoni, Giovanni [LENITEM - Laboratory of Epidemiology Neuroimaging and Telemedicine, Brescia (Italy)

    2010-01-15

    To reveal the morphological and functional substrates of memory impairment and conversion to Alzheimer disease (AD) from the stage of amnestic mild cognitive impairment (aMCI). Brain MRI and FDG-PET were performed in 20 patients with aMCI and 12 controls at baseline. During a mean follow-up of about 2 years, 9 patients developed AD (converters), and 11 did not (nonconverters). All images were processed with SPM2. FDG-PET and segmented grey matter (GM) images were compared in: (1) converters versus controls, (2) nonconverters versus controls, and (3) converters versus nonconverters. As compared to controls, converters showed lower GM density in the left parahippocampal gyrus and both thalami, and hypometabolism in the precuneus, posterior cingulate and superior parietal lobule in the left hemisphere. Hypometabolism was found in nonconverters as compared to controls in the left precuneus and posterior cingulated gyrus. As compared to nonconverters, converters showed significant hypometabolism in the left middle and superior temporal gyri. The discordant topography between atrophy and hypometabolism reported in AD is already present at the aMCI stage. Posterior cingulate-precuneus hypometabolism seemed to be an early sign of memory deficit, whereas hypometabolism in the left temporal cortex marked the conversion to AD. (orig.)

  1. Automated detection of periventricular veins on 7 T brain MRI

    Science.gov (United States)

    Kuijf, Hugo J.; Bouvy, Willem H.; Zwanenburg, Jaco J. M.; Viergever, Max A.; Biessels, Geert Jan; Vincken, Koen L.

    2015-03-01

    Cerebral small vessel disease is common in elderly persons and a leading cause of cognitive decline, dementia, and acute stroke. With the introduction of ultra-high field strength 7.0T MRI, it is possible to visualize small vessels in the brain. In this work, a proof-of-principle study is conducted to assess the feasibility of automatically detecting periventricular veins. Periventricular veins are organized in a fan-pattern and drain venous blood from the brain towards the caudate vein of Schlesinger, which is situated along the lateral ventricles. Just outside this vein, a region-of- interest (ROI) through which all periventricular veins must cross is defined. Within this ROI, a combination of the vesselness filter, tubular tracking, and hysteresis thresholding is applied to locate periventricular veins. All detected locations were evaluated by an expert human observer. The results showed a positive predictive value of 88% and a sensitivity of 95% for detecting periventricular veins. The proposed method shows good results in detecting periventricular veins in the brain on 7.0T MR images. Compared to previous works, that only use a 1D or 2D ROI and limited image processing, our work presents a more comprehensive definition of the ROI, advanced image processing techniques to detect periventricular veins, and a quantitative analysis of the performance. The results of this proof-of-principle study are promising and will be used to assess periventricular veins on 7.0T brain MRI.

  2. Atypical Brain Activation during Simple & Complex Levels of Processing in Adult ADHD: An fMRI Study

    Science.gov (United States)

    Hale, T. Sigi; Bookheimer, Susan; McGough, James J.; Phillips, Joseph M.; McCracken, James T.

    2007-01-01

    Objective: Executive dysfunction in ADHD is well supported. However, recent studies suggest that more fundamental impairments may be contributing. We assessed brain function in adults with ADHD during simple and complex forms of processing. Method: We used functional magnetic resonance imaging with forward and backward digit spans to investigate…

  3. FULLY AUTOMATIC FRAMEWORK FOR SEGMENTATION OF BRAIN MRI IMAGE

    Institute of Scientific and Technical Information of China (English)

    Lin Pan; Zheng Chongxun; Yang Yong; Gu Jianwen

    2005-01-01

    Objective To propose an automatic framework for segmentation of brain image in this paper. Methods The brain MRI image segmentation framework consists of three-step segmentation procedures. First, Non-brain structures removal by level set method. Then, the non-uniformity correction method is based on computing estimates of tissue intensity variation. Finally, it uses a statistical model based on Markov random filed for MRI brain image segmentation. The brain tissue can be classified into cerebrospinal fluid, white matter and gray matter. Results To evaluate the proposed our method, we performed two sets of experiments, one on simulated MR and another on real MR brain data. Conclusion The efficacy of the brain MRI image segmentation framework has been demonstrated by the extensive experiments. In the future, we are also planning on a large-scale clinical evaluation of this segmentation framework.

  4. Optimizing full-brain coverage in human brain MRI through population distributions of brain size

    NARCIS (Netherlands)

    Mennes, M.; Jenkinson, M.; Valabregue, R.; Buitelaar, J.; Beckmann, C.; Smith, S.

    2014-01-01

    When defining an MRI protocol, brain researchers need to set multiple interdependent parameters that define repetition time (TR), voxel size, field-of-view (FOV), etc. Typically, researchers aim to image the full brain, making the expected FOV an important parameter to consider. Especially in 2D-EPI

  5. Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people A functional MRI study

    Institute of Scientific and Technical Information of China (English)

    Junqi Chen; Yong Huang; Xinsheng Lai; Chunzhi Tang; Junjun Yang; Hua Chen; Tongjun Zeng; Junxian Wu; Shanshan Qu

    2013-01-01

    In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions.

  6. Three-dimensional brain mapping using fMRI

    Energy Technology Data Exchange (ETDEWEB)

    Fukunaga, Masaki; Tanaka, Chuzo; Umeda, Masahiro; Ebisu, Toshihiko; Aoki, Ichio [Meiji Univ. of Oriental Medicine, Hiyoshi, Kyoto (Japan); Higuchi, Toshihiro; Naruse, Shoji

    1997-10-01

    Functional mapping of the activated brain, the location and extent of the activated area were determined, during motor tasks and sensory stimulation using fMRI superimposed on 3D anatomical MRI. Twelve volunteers were studied. The fMR images were acquired using a 2D gradient echo echo planar imaging sequence. The 3D anatomical MR images of the whole brain were acquired using a conventional 3D gradient echo sequence. Motor tasks were sequential opposition of fingers, clenching a hand and elbow flexion. Somatosensory stimulation were administered by scrubbing the palm and sole with a washing sponge. Visual stimulation consisted of full visual field stimulation. Data were analyzed by the cross-correlation method. Transversal fMR images and anatomical images were reconstructed using both volume-, surface-rendering methods, and reconstructed for coronal and sagittal sections. Activated areas were expressed using the three primary colors. Motor tasks activated the contralateral primary motor area (M1), the primary somatosensory area (S1) and the supplementary motor area (SMA). Somatosensory tasks activated the contralateral S1, M1 and secondary sensory area (S2). Activated areas during full visual field stimulation was observed in the bilateral occipital lobe, including both the primary cortex. Three-dimensional brain mapping allowed visualization of the anatomical location and extent of the activated brain during both motor task and sensory stimulation. Using this method we could obtain a functional map similar to the Penfield`s schema. (author)

  7. Language networks in children: Evidence from functional MRI studies

    OpenAIRE

    2009-01-01

    We review functional MRI and other neuroimaging studies of language skills in children from infancy to adulthood. These studies show developmental changes in the networks of brain regions supporting language, which can be affected by brain injuries or neurological disorders. Particular aspects of language rely on networks that lateralize to the dominant hemisphere; others rely on bilateral or non-dominant mechanisms. Multiple fMRI tasks for pediatric patients characterize functional brain reo...

  8. Overlapping and distinct brain regions involved in estimating the spatial position of numerical and non-numerical magnitudes: an fMRI study.

    Science.gov (United States)

    Vogel, Stephan E; Grabner, Roland H; Schneider, Michael; Siegler, Robert S; Ansari, Daniel

    2013-04-01

    How are numerical and non-numerical magnitudes processed in the brain? Brain imaging research, primarily using comparison paradigms (i.e. judging which of two magnitudes is larger), has provided strong evidence demonstrating that the intraparietal sulcus (IPS) is a key region for processing both numerical (e.g. Arabic numerals, arrays of dots) and non-numerical magnitudes (e.g. height, brightness). These studies have suggested that there is both activation overlap and segregation in the brain regions involved in processing different dimensions of magnitude. In the present functional Magnetic Resonance Imaging (fMRI) study, we extended this line of investigation by probing the brain mechanisms underlying the mapping of numerical (Arabic numerals) and non-numerical magnitudes (brightness levels) onto a number line. Consistent with previous studies the present results revealed that number and brightness estimation was associated with overlapping activation within right lateralized areas of the posterior IPS. In addition, the contrast between number and brightness estimation revealed that bilateral anterior regions of the IPS are specifically involved in the process of estimating the position of symbolic numbers onto a number line. Furthermore, we found a significant influence of landmark reference points (0, 50 and 100) on brain activation in the right IPS for number estimation only. No regions were found to be specifically associated with brightness estimation. The results of this study reveal that the estimation of both numerical and non-numerical magnitude are associated with the engagement of a right lateralized magnitude system, but that symbolic number estimation is associated with additional engagement of bilateral regions of the anterior IPS.

  9. MRI segmentation of the human brain: challenges, methods, and applications.

    Science.gov (United States)

    Despotović, Ivana; Goossens, Bart; Philips, Wilfried

    2015-01-01

    Image segmentation is one of the most important tasks in medical image analysis and is often the first and the most critical step in many clinical applications. In brain MRI analysis, image segmentation is commonly used for measuring and visualizing the brain's anatomical structures, for analyzing brain changes, for delineating pathological regions, and for surgical planning and image-guided interventions. In the last few decades, various segmentation techniques of different accuracy and degree of complexity have been developed and reported in the literature. In this paper we review the most popular methods commonly used for brain MRI segmentation. We highlight differences between them and discuss their capabilities, advantages, and limitations. To address the complexity and challenges of the brain MRI segmentation problem, we first introduce the basic concepts of image segmentation. Then, we explain different MRI preprocessing steps including image registration, bias field correction, and removal of nonbrain tissue. Finally, after reviewing different brain MRI segmentation methods, we discuss the validation problem in brain MRI segmentation.

  10. Who wants a free brain scan? Assessing and correcting for recruitment biases in a population-based sMRI pilot study.

    Science.gov (United States)

    Ganguli, Mary; Lee, Ching-Wen; Hughes, Tiffany; Snitz, Beth E; Jakubcak, Jennifer; Duara, Ranjan; Chang, Chung-Chou H

    2015-06-01

    Neuroimaging research is usually conducted in volunteers who meet a priori selection criteria. Selection/volunteer bias is assumed but cannot be assessed. During an ongoing population-based cohort study of 1982 older adults, we asked 1702 active participants about their interest in undergoing a research brain scan. Compared with those not interested, the 915 potentially interested individuals were significantly younger, more likely to be male, better educated, generally healthier, and more likely to be cognitively intact and dementia-free. In 48 of the interested individuals, we conducted a previously reported pilot structural magnetic resonance imaging (sMRI) study modelling mild cognitive impairment (MCI) vs. normal cognition, and Clinical Dementia Rating (CDR) = 0.5 vs. CDR = 0, as a function of sMRI atrophy ratings. We now compare these 48 individuals (1) with all interested participants, to assess selection bias; (2) with all who had been asked about their interest, to assess volunteer bias; and (3) with the entire study cohort, to assess attrition bias from those who had dropped out before the question was asked. Using these data in propensity score models, we generated weights which we applied to logistic regression models reanalyzing the data from the pilot sMRI study. These weighted models adjusted, in turn, for selection bias, interest/volunteer bias, and attrition bias. They show fewer regions of interest to be associated with MCI/ CDR than were in the original unweighted models. When study participants are drawn from a well-characterized population, they can be compared with non-participants, and the information used to correct study results for potential bias and thus provide more generalizable estimates.

  11. MRI magnetic field stimulates rotational sensors of the brain.

    Science.gov (United States)

    Roberts, Dale C; Marcelli, Vincenzo; Gillen, Joseph S; Carey, John P; Della Santina, Charles C; Zee, David S

    2011-10-11

    Vertigo in and around magnetic resonance imaging (MRI) machines has been noted for years [1, 2]. Several mechanisms have been suggested to explain these sensations [3, 4], yet without direct, objective measures, the cause is unknown. We found that all of our healthy human subjects developed a robust nystagmus while simply lying in the static magnetic field of an MRI machine. Patients lacking labyrinthine function did not. We use the pattern of eye movements as a measure of vestibular stimulation to show that the stimulation is static (continuous, proportional to static magnetic field strength, requiring neither head movement nor dynamic change in magnetic field strength) and directional (sensitive to magnetic field polarity and head orientation). Our calculations and geometric model suggest that magnetic vestibular stimulation (MVS) derives from a Lorentz force resulting from interaction between the magnetic field and naturally occurring ionic currents in the labyrinthine endolymph fluid. This force pushes on the semicircular canal cupula, leading to nystagmus. We emphasize that the unique, dual role of endolymph in the delivery of both ionic current and fluid pressure, coupled with the cupula's function as a pressure sensor, makes magnetic-field-induced nystagmus and vertigo possible. Such effects could confound functional MRI studies of brain behavior, including resting-state brain activity.

  12. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with a right hemispheric lesion.

    Science.gov (United States)

    Tanaka, Satoshi; Seki, Keiko; Hanakawa, Takashi; Harada, Madoka; Sugawara, Sho K; Sadato, Norihiro; Watanabe, Katsumi; Honda, Manabu

    2012-01-01

    The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her "mental abacus" and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex (PMd) and inferior parietal lobule (IPL). Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca's area and the left dorsolateral prefrontal and IPLs, to the visuospatial-related brain areas including the left superior parietal lobule (SPL), according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral SPL, and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery. This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case "abacus-based acalculia." Together with previous neuroimaging studies, the present result suggests an important role for the PMd and parietal cortex in the superior arithmetic ability of abacus users.

  13. Abacus in the brain: a longitudinal functional MRI study of a skilled abacus user with the right hemispheric lesion

    Directory of Open Access Journals (Sweden)

    Satoshi eTanaka

    2012-08-01

    Full Text Available The abacus, a traditional physical calculation device, is still widely used in Asian countries. Previous behavioral work has shown that skilled abacus users perform rapid and precise mental arithmetic by manipulating a mental representation of an abacus, which is based on visual imagery. However, its neurophysiological basis remains unclear. Here, we report the case of a patient who was a good abacus user, but transiently lost her mental abacus and superior arithmetic performance after a stroke owing to a right hemispheric lesion including the dorsal premotor cortex and inferior parietal lobule.Functional magnetic resonance imaging experiments were conducted 6 and 13 months after her stroke. In the mental calculation task, her brain activity was shifted from the language-related areas, including Broca’s area and the left dorsolateral prefrontal and inferior parietal lobules, to the visuospatial-related brain areas including the left superior parietal lobule, according to the recovery of her arithmetic abilities. In the digit memory task, activities in the bilateral superior parietal lobule and right visual association cortex were also observed after recovery. The shift of brain activities was consistent with her subjective report that she was able to shift the calculation strategy from linguistic to visuospatial as her mental abacus became stable again. In a behavioral experiment using an interference paradigm, a visual presentation of an abacus picture, but not a human face picture, interfered with the performance of her digit memory, confirming her use of the mental abacus after recovery.This is the first case report on the impairment of the mental abacus by a brain lesion and on recovery-related brain activity. We named this rare case abacus-based acalculia. Together with previous neuroimaging studies, the present result suggests an important role for the dorsal premotor cortex and parietal cortex in the superior arithmetic ability of

  14. Branding and a child’s brain: an fMRI study of neural responses to logos

    Science.gov (United States)

    Bruce, Jared M.; Black, William R.; Lepping, Rebecca J.; Henry, Janice M.; Cherry, Joseph Bradley C.; Martin, Laura E.; Papa, Vlad B.; Davis, Ann M.; Brooks, William M.; Savage, Cary R.

    2014-01-01

    Branding and advertising have a powerful effect on both familiarity and preference for products, yet no neuroimaging studies have examined neural response to logos in children. Food advertising is particularly pervasive and effective in manipulating choices in children. The purpose of this study was to examine how healthy children’s brains respond to common food and other logos. A pilot validation study was first conducted with 32 children to select the most culturally familiar logos, and to match food and non-food logos on valence and intensity. A new sample of 17 healthy weight children were then scanned using functional magnetic resonance imaging. Food logos compared to baseline were associated with increased activation in orbitofrontal cortex and inferior prefrontal cortex. Compared to non-food logos, food logos elicited increased activation in posterior cingulate cortex. Results confirmed that food logos activate some brain regions in children known to be associated with motivation. This marks the first study in children to examine brain responses to culturally familiar logos. Considering the pervasiveness of advertising, research should further investigate how children respond at the neural level to marketing. PMID:22997054

  15. Acute caffeine administration impact on working memory-related brain activation and functional connectivity in the elderly: a BOLD and perfusion MRI study.

    Science.gov (United States)

    Haller, S; Rodriguez, C; Moser, D; Toma, S; Hofmeister, J; Sinanaj, I; Van De Ville, D; Giannakopoulos, P; Lovblad, K-O

    2013-10-10

    In young individuals, caffeine-mediated blockade of adenosine receptors and vasoconstriction has direct repercussions on task-related activations, changes in functional connectivity, as well as global vascular effects. To date, no study has explored the effect of caffeine on brain activation patterns during highly demanding cognitive tasks in the elderly. This prospective, placebo-controlled crossover design comprises 24 healthy elderly individuals (mean age 68.8 ± 4.0 years, 17 females) performing a 2-back working memory (WM) task in functional magnetic resonance imaging (fMRI). Analyses include complimentary assessment of task-related activations (general linear model, GLM), functional connectivity (tensorial independent component analysis, TICA), and baseline perfusion (arterial spin labeling). Despite a reduction in whole-brain global perfusion (-22.7%), caffeine-enhanced task-related GLM activation in a local and distributed network is most pronounced in the bilateral striatum and to a lesser degree in the right middle and inferior frontal gyrus, bilateral insula, left superior and inferior parietal lobule as well as in the cerebellum bilaterally. TICA was significantly enhanced (+8.2%) in caffeine versus placebo in a distributed and task-relevant network including the pre-frontal cortex, the supplementary motor area, the ventral premotor cortex and the parietal cortex as well as the occipital cortex (visual stimuli) and basal ganglia. The inverse comparison of placebo versus caffeine had no significant difference. Activation strength of the task-relevant-network component correlated with response accuracy for caffeine yet not for placebo, indicating a selective cognitive effect of caffeine. The present findings suggest that acute caffeine intake enhances WM-related brain activation as well as functional connectivity of blood oxygen level-dependent fMRI in elderly individuals.

  16. Mapping Human Brain Function with MRI at 7 Tesla

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ In the past decade, the most significant development in MRI is the introduction of fMRI, which permits the mapping of human brain function with exquisite details noninvasively. Functional mapping can be achieved by measuring changes in the blood oxygenation level (I.e. The BOLD contrast) or cerebral blood flow.

  17. fMRI Brain-Computer Interface: A Tool for Neuroscientific Research and Treatment

    Directory of Open Access Journals (Sweden)

    Ranganatha Sitaram

    2007-01-01

    Full Text Available Brain-computer interfaces based on functional magnetic resonance imaging (fMRI-BCI allow volitional control of anatomically specific regions of the brain. Technological advancement in higher field MRI scanners, fast data acquisition sequences, preprocessing algorithms, and robust statistical analysis are anticipated to make fMRI-BCI more widely available and applicable. This noninvasive technique could potentially complement the traditional neuroscientific experimental methods by varying the activity of the neural substrates of a region of interest as an independent variable to study its effects on behavior. If the neurobiological basis of a disorder (e.g., chronic pain, motor diseases, psychopathy, social phobia, depression is known in terms of abnormal activity in certain regions of the brain, fMRI-BCI can be targeted to modify activity in those regions with high specificity for treatment. In this paper, we review recent results of the application of fMRI-BCI to neuroscientific research and psychophysiological treatment.

  18. Current status and future role of brain PET/MRI in clinical and research settings

    Energy Technology Data Exchange (ETDEWEB)

    Werner, P.; Barthel, H.; Sabri, O. [University Hospital Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Drzezga, A. [University Hospital Cologne, Department of Nuclear Medicine, Koeln (Germany)

    2015-01-09

    Hybrid PET/MRI systematically offers a complementary combination of two modalities that has often proven itself superior to the single modality approach in the diagnostic work-up of many neurological and psychiatric diseases. Emerging PET tracers, technical advances in multiparametric MRI and obvious workflow advantages may lead to a significant improvement in the diagnosis of dementia disorders, neurooncological diseases, epilepsy and neurovascular diseases using PET/MRI. Moreover, simultaneous PET/MRI is well suited to complex studies of brain function in which fast fluctuations of brain signals (e.g. related to task processing or in response to pharmacological interventions) need to be monitored on multiple levels. Initial simultaneous studies have already demonstrated that these complementary measures of brain function can provide new insights into the functional and structural organization of the brain. (orig.)

  19. State of the art survey on MRI brain tumor segmentation.

    Science.gov (United States)

    Gordillo, Nelly; Montseny, Eduard; Sobrevilla, Pilar

    2013-10-01

    Brain tumor segmentation consists of separating the different tumor tissues (solid or active tumor, edema, and necrosis) from normal brain tissues: gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). In brain tumor studies, the existence of abnormal tissues may be easily detectable most of the time. However, accurate and reproducible segmentation and characterization of abnormalities are not straightforward. In the past, many researchers in the field of medical imaging and soft computing have made significant survey in the field of brain tumor segmentation. Both semiautomatic and fully automatic methods have been proposed. Clinical acceptance of segmentation techniques has depended on the simplicity of the segmentation, and the degree of user supervision. Interactive or semiautomatic methods are likely to remain dominant in practice for some time, especially in these applications where erroneous interpretations are unacceptable. This article presents an overview of the most relevant brain tumor segmentation methods, conducted after the acquisition of the image. Given the advantages of magnetic resonance imaging over other diagnostic imaging, this survey is focused on MRI brain tumor segmentation. Semiautomatic and fully automatic techniques are emphasized.

  20. Total and regional brain volumes in a population-based normative sample from 4 to 18 years: the NIH MRI Study of Normal Brain Development.

    Science.gov (United States)

    2012-01-01

    Using a population-based sampling strategy, the National Institutes of Health (NIH) Magnetic Resonance Imaging Study of Normal Brain Development compiled a longitudinal normative reference database of neuroimaging and correlated clinical/behavioral data from a demographically representative sample of healthy children and adolescents aged newborn through early adulthood. The present paper reports brain volume data for 325 children, ages 4.5-18 years, from the first cross-sectional time point. Measures included volumes of whole-brain gray matter (GM) and white matter (WM), left and right lateral ventricles, frontal, temporal, parietal and occipital lobe GM and WM, subcortical GM (thalamus, caudate, putamen, and globus pallidus), cerebellum, and brainstem. Associations with cross-sectional age, sex, family income, parental education, and body mass index (BMI) were evaluated. Key observations are: 1) age-related decreases in lobar GM most prominent in parietal and occipital cortex; 2) age-related increases in lobar WM, greatest in occipital, followed by the temporal lobe; 3) age-related trajectories predominantly curvilinear in females, but linear in males; and 4) small systematic associations of brain tissue volumes with BMI but not with IQ, family income, or parental education. These findings constitute a normative reference on regional brain volumes in children and adolescents.

  1. MRI Segmentation of the Human Brain: Challenges, Methods, and Applications

    Directory of Open Access Journals (Sweden)

    Ivana Despotović

    2015-01-01

    Full Text Available Image segmentation is one of the most important tasks in medical image analysis and is often the first and the most critical step in many clinical applications. In brain MRI analysis, image segmentation is commonly used for measuring and visualizing the brain’s anatomical structures, for analyzing brain changes, for delineating pathological regions, and for surgical planning and image-guided interventions. In the last few decades, various segmentation techniques of different accuracy and degree of complexity have been developed and reported in the literature. In this paper we review the most popular methods commonly used for brain MRI segmentation. We highlight differences between them and discuss their capabilities, advantages, and limitations. To address the complexity and challenges of the brain MRI segmentation problem, we first introduce the basic concepts of image segmentation. Then, we explain different MRI preprocessing steps including image registration, bias field correction, and removal of nonbrain tissue. Finally, after reviewing different brain MRI segmentation methods, we discuss the validation problem in brain MRI segmentation.

  2. Brain MRI volumetry in a single patient with mild traumatic brain injury.

    Science.gov (United States)

    Ross, David E; Castelvecchi, Cody; Ochs, Alfred L

    2013-01-01

    This letter to the editor describes the case of a 42 year old man with mild traumatic brain injury and multiple neuropsychiatric symptoms which persisted for a few years after the injury. Initial CT scans and MRI scans of the brain showed no signs of atrophy. Brain volume was measured using NeuroQuant®, an FDA-approved, commercially available software method. Volumetric cross-sectional (one point in time) analysis also showed no atrophy. However, volumetric longitudinal (two points in time) analysis showed progressive atrophy in several brain regions. This case illustrated in a single patient the principle discovered in multiple previous group studies, namely that the longitudinal design is more powerful than the cross-sectional design for finding atrophy in patients with traumatic brain injury.

  3. Aberrant Brain Regional Homogeneity and Functional Connectivity in Middle-Aged T2DM Patients: A Resting-State Functional MRI Study

    Science.gov (United States)

    Liu, Daihong; Duan, Shanshan; Zhang, Jiuquan; Zhou, Chaoyang; Liang, Minglong; Yin, Xuntao; Wei, Ping; Wang, Jian

    2016-01-01

    Type 2 diabetes mellitus (T2DM) has been associated with cognitive impairment. However, its neurological mechanism remains elusive. Combining regional homogeneity (ReHo) and functional connectivity (FC) analyses, the present study aimed to investigate brain functional alterations in middle-aged T2DM patients, which could provide complementary information for the neural substrates underlying T2DM-associated brain dysfunction. Twenty-five T2DM patients and 25 healthy controls were involved in neuropsychological testing and structural and resting-state functional magnetic resonance imaging (rs-fMRI) data acquisition. ReHo analysis was conducted to determine the peak coordinates of brain regions with abnormal local brain activity synchronization. Then, the identified brain regions were considered as seeds, and FC between these brain regions and global voxels was computed. Finally, the potential correlations between the imaging indices and neuropsychological data were also explored. Compared with healthy controls, T2DM patients exhibited higher ReHo values in the anterior cingulate gyrus (ACG) and lower ReHo in the right fusiform gyrus (FFG), right precentral gyrus (PreCG) and right medial orbit of the superior frontal gyrus (SFG). Considering these areas as seed regions, T2DM patients displayed aberrant FC, mainly in the frontal and parietal lobes. The pattern of FC alterations in T2DM patients was characterized by decreased connectivity and positive to negative or negative to positive converted connectivity. Digital Span Test (DST) forward scores revealed significant correlations with the ReHo values of the right PreCG (ρ = 0.527, p = 0.014) and FC between the right FFG and middle temporal gyrus (MTG; ρ = −0.437, p = 0.048). Our findings suggest that T2DM patients suffer from cognitive dysfunction related to spatially local and remote brain activity synchronization impairment. The patterns of ReHo and FC alterations shed light on the mechanisms underlying T2DM

  4. Mapping Numerical Processing, Reading, and Executive Functions in the Developing Brain: An fMRI Meta-Analysis of 52 Studies Including 842 Children

    Science.gov (United States)

    Houde, Olivier; Rossi, Sandrine; Lubin, Amelie; Joliot, Marc

    2010-01-01

    Tracing the connections from brain functions to children's cognitive development and education is a major goal of modern neuroscience. We performed the first meta-analysis of functional magnetic resonance imaging (fMRI) data obtained over the past decade (1999-2008) on more than 800 children and adolescents in three core systems of cognitive…

  5. Pattern of structural brain changes in social anxiety disorder after cognitive behavioral group therapy: a longitudinal multimodal MRI study.

    Science.gov (United States)

    Steiger, V R; Brühl, A B; Weidt, S; Delsignore, A; Rufer, M; Jäncke, L; Herwig, U; Hänggi, J

    2016-12-06

    Social anxiety disorder (SAD) is characterized by fears of social and performance situations. Cognitive behavioral group therapy (CBGT) has in general positive effects on symptoms, distress and avoidance in SAD. Prior studies found increased cortical volumes and decreased fractional anisotropy (FA) in SAD compared with healthy controls (HCs). Thirty-three participants diagnosed with SAD attended in a 10-week CBGT and were scanned before and after therapy. We applied three neuroimaging methods-surface-based morphometry, diffusion tensor imaging and network-based statistics-each with specific longitudinal processing protocols, to investigate CBGT-induced structural brain alterations of the gray and white matter (WM). Surface-based morphometry revealed a significant cortical volume reduction (pre- to post-treatment) in the left inferior parietal cortex, as well as a positive partial correlation between treatment success (indexed by reductions in Liebowitz Social Anxiety Scale) and reductions in cortical volume in bilateral dorsomedial prefrontal cortex. Diffusion tensor imaging analysis revealed a significant increase in FA in bilateral uncinate fasciculus and right inferior longitudinal fasciculus. Network-based statistics revealed a significant increase of structural connectivity in a frontolimbic network. No partial correlations with treatment success have been found in WM analyses. For, we believe, the first time, we present a distinctive pattern of longitudinal structural brain changes after CBGT measured with three established magnetic resonance imaging analyzing techniques. Our findings are in line with previous cross-sectional, unimodal SAD studies and extent them by highlighting anatomical brain alterations that point toward the level of HCs in parallel with a reduction in SAD symptomatology.Molecular Psychiatry advance online publication, 6 December 2016; doi:10.1038/mp.2016.217.

  6. Homayoun as a Persian Music Scale on Non-Musician’s Brain: an fMRI Study

    Directory of Open Access Journals (Sweden)

    Farzaneh Pouladi

    2011-10-01

    Full Text Available The aim of this study was to get to a neurological evaluation of one of the Persian music scales, Homayoun, on brain activation of non-musician subjects. We selected this scale because Homayoun is one of the main scales in Persian classical music which is similar to minor mode in western scales. This study was performed on 19 right handed subjects, Aging 22-31. Here some pices from Homayoun Dastgah are used in both rhythmic and non- rhythmic. The results of this study revealed the brain activities for each of rhythmic and non-rhythmic versions of Homayoun Dastgah. The activated regions for non-rhythmic Homayoun contained: right and left Subcallosal Cortex, left Medial Frontal cortex, left anterior Cingulate Gyrus, left Frontal Pole and for rhythmic Homayoun contained: left Precentral Gyrus, left Precuneous Cortex, left anterior Supramarginal, left Superior Parietal Lobule, left Postcentral Gyrus. Also, we acquired amygdala area in both pieces of music. Based on arousal effects of rhythm and Damasio's somatic marker hypothesis, non-rhythmic Homayoun activates regions related to emotion and thinking while activity of rhythmic Homayoun is related to areas of movement and motion.

  7. How the brain learns how few are "many": An fMRI study of the flexibility of quantifier semantics.

    Science.gov (United States)

    Heim, Stefan; McMillan, Corey T; Clark, Robin; Baehr, Laura; Ternes, Kylie; Olm, Christopher; Min, Nam Eun; Grossman, Murray

    2016-01-15

    Previous work has shown that the meaning of a quantifier such as "many" or "few" depends in part on quantity. However, the meaning of a quantifier may vary depending on the context, e.g. in the case of common entities such as "many ants" (perhaps several thousands) compared to endangered species such as "many pandas" (perhaps a dozen). In a recent study (Heim et al., 2015 Front. Psychol.) we demonstrated that the relative meaning of "many" and "few" may be changed experimentally. In a truth value judgment task, displays with 40% of circles in a named color initially had a low probability of being labeled "many". After a training phase, the likelihood of acceptance 40% as "many" increased. Moreover, the semantic learning effect also generalized to the related quantifier "few" which had not been mentioned in the training phase. Thus, fewer 40% arrays were considered "few." In the present study, we tested the hypothesis that this semantic adaptation effect was supported by cytoarchitectonic Brodmann area (BA) 45 in Broca's region which may contribute to semantic evaluation in the context of language and quantification. In an event-related fMRI study, 17 healthy volunteers performed the same paradigm as in the previous behavioral study. We found a relative signal increase when comparing the critical, trained proportion to untrained proportions. This specific effect was found in left BA 45 for the trained quantifier "many", and in left BA 44 for both quantifiers, reflecting the semantic adjustment for the untrained but related quantifier "few." These findings demonstrate the neural basis for processing the flexible meaning of a quantifier, and illustrate the neuroanatomical structures that contribute to variable meanings that can be associated with a word when used in different contexts.

  8. Brain MRI changes in chronic liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Skehan, S. [Department of Diagnostic Imaging, St. Vincent`s Hospital, Elm Park, Dublin 4 (Ireland); Norris, S. [Liver Unit, St. Vincent`s Hospital, Elm Park, Dublin 4 (Ireland); Hegarty, J. [Liver Unit, St. Vincent`s Hospital, Elm Park, Dublin 4 (Ireland); Owens, A. [Department of Diagnostic Imaging, St. Vincent`s Hospital, Elm Park, Dublin 4 (Ireland); MacErlaine, D. [Department of Diagnostic Imaging, St. Vincent`s Hospital, Elm Park, Dublin 4 (Ireland)

    1997-08-01

    Cirrhotic patients are known to have abnormally high signal principally in the globus pallidus on non-contrast T1-weighted MRI. The purpose of this study was to relate MR changes to clinical and pathological features of chronic liver disease. We confirmed abnormally high signal in the globus pallidus on T1-weighted images in 25 of 28 patients with chronic liver disease, showing that it also occurs in patients who have not yet progressed to cirrhosis. Changes were seen in patients both with and without clinical portosystemic shunting. This abnormality is not responsible for hepatic encephalopathy. Cholestatic disease was more likely to produce marked changes than non-cholestatic disease. No statistically significant correlation was demonstrated between the severity of liver disease and the degree of MR abnormality. However, marked improvement in MR appearances was seen after successful liver transplantation. (orig.). With 3 figs., 4 tabs.

  9. Orchestrating Proactive and Reactive Mechanisms for Filtering Distracting Information: Brain-Behavior Relationships Revealed by a Mixed-Design fMRI Study.

    Science.gov (United States)

    Marini, Francesco; Demeter, Elise; Roberts, Kenneth C; Chelazzi, Leonardo; Woldorff, Marty G

    2016-01-20

    probability, thereby aiding task performance. Significance statement: Irrelevant stimuli distract people and impair their attentional performance. Here, we studied how the brain deals with distracting stimuli using a hybrid block/event-related fMRI design and a task that varied the probability of the occurrence of such distracting stimuli. The results suggest that when distraction is likely, a region in right frontal cortex proactively implements attentional control mechanisms to help filter out any distracting stimuli that might occur. In contrast, when distracting input occurs infrequently, this region is more reactively engaged to help limit the negative consequences of the distracters on behavioral performance. Our results thus help illuminate how the brain flexibly responds under differing attentional demands to engender effective behavior.

  10. Once-weekly 22microg subcutaneous IFN-beta-1a in secondary progressive MS: a 3-year follow-up study on brain MRI measurements and serum MMP-9 levels

    DEFF Research Database (Denmark)

    Wu, X; Kuusisto, H; Dastidar, P;

    2007-01-01

    OBJECTIVE: To study the effect of weekly injected subcutaneous interferon (IFN)-beta-1a 22 microg on the extent of brain lesions on magnetic resonance imaging (MRI) and the level of serum matrix metalloproteinase (MMP)-9 in patients with secondary progressive multiple sclerosis (SPMS). SUBJECTS...

  11. How Does Brain Activation Differ in Children with Unilateral Cerebral Palsy Compared to Typically Developing Children, during Active and Passive Movements, and Tactile Stimulation? An fMRI Study

    Science.gov (United States)

    Van de Winckel, Ann; Klingels, Katrijn; Bruyninckx, Frans; Wenderoth, Nici; Peeters, Ron; Sunaert, Stefan; Van Hecke, Wim; De Cock, Paul; Eyssen, Maria; De Weerdt, Willy; Feys, Hilde

    2013-01-01

    The aim of the functional magnetic resonance imaging (fMRI) study was to investigate brain activation associated with active and passive movements, and tactile stimulation in 17 children with right-sided unilateral cerebral palsy (CP), compared to 19 typically developing children (TD). The active movements consisted of repetitive opening and…

  12. Serum BDNF correlates with connectivity in the (pre)motor hub in the aging human brain--a resting-state fMRI pilot study.

    Science.gov (United States)

    Mueller, Karsten; Arelin, Katrin; Möller, Harald E; Sacher, Julia; Kratzsch, Jürgen; Luck, Tobias; Riedel-Heller, Steffi; Villringer, Arno; Schroeter, Matthias L

    2016-02-01

    Brain-derived neurotrophic factor (BDNF) has been discussed to be involved in plasticity processes in the human brain, in particular during aging. Recently, aging and its (neurodegenerative) diseases have increasingly been conceptualized as disconnection syndromes. Here, connectivity changes in neural networks (the connectome) are suggested to be the most relevant and characteristic features for such processes or diseases. To further elucidate the impact of aging on neural networks, we investigated the interaction between plasticity processes, brain connectivity, and healthy aging by measuring levels of serum BDNF and resting-state fMRI data in 25 young (mean age 24.8 ± 2.7 (SD) years) and 23 old healthy participants (mean age, 68.6 ± 4.1 years). To identify neural hubs most essentially related to serum BDNF, we applied graph theory approaches, namely the new data-driven and parameter-free approach eigenvector centrality (EC) mapping. The analysis revealed a positive correlation between serum BDNF and EC in the premotor and motor cortex in older participants in contrast to young volunteers, where we did not detect any association. This positive relationship between serum BDNF and EC appears to be specific for older adults. Our results might indicate that the amount of physical activity and learning capacities, leading to higher BDNF levels, increases brain connectivity in (pre)motor areas in healthy aging in agreement with rodent animal studies. Pilot results have to be replicated in a larger sample including behavioral data to disentangle the cause for the relationship between BDNF levels and connectivity.

  13. Likelihood-Based Hypothesis Tests for Brain Activation Detection From MRI Data Disturbed by Colored Noise: A Simulation Study

    NARCIS (Netherlands)

    Den Dekker, A.J.; Poot, D.H.J.; Bos, R.; Sijbers, J.

    2009-01-01

    Functional magnetic resonance imaging (fMRI) data that are corrupted by temporally colored noise are generally preprocessed (i.e., prewhitened or precolored) prior to functional activation detection. In this paper, we propose likelihood-based hypothesis tests that account for colored noise directly

  14. Enhancement of Odor-Induced Activity in the Canine Brain by Zinc Nanoparticles: A Functional MRI Study in Fully Unrestrained Conscious Dogs.

    Science.gov (United States)

    Jia, Hao; Pustovyy, Oleg M; Wang, Yun; Waggoner, Paul; Beyers, Ronald J; Schumacher, John; Wildey, Chester; Morrison, Edward; Salibi, Nouha; Denney, Thomas S; Vodyanoy, Vitaly J; Deshpande, Gopikrishna

    2016-01-01

    Using noninvasive in vivo functional magnetic resonance imaging (fMRI), we demonstrate that the enhancement of odorant response of olfactory receptor neurons by zinc nanoparticles leads to increase in activity in olfaction-related and higher order areas of the dog brain. To study conscious dogs, we employed behavioral training and optical motion tracking for reducing head motion artifacts. We obtained brain activation maps from dogs in both anesthetized state and fully conscious and unrestrained state. The enhancement effect of zinc nanoparticles was higher in conscious dogs with more activation in higher order areas as compared with anesthetized dogs. In conscious dogs, voxels in the olfactory bulb and hippocampus showed higher activity to odorants mixed with zinc nanoparticles as compared with pure odorants, odorants mixed with gold nanoparticles as well as zinc nanoparticles alone. These regions have been implicated in odor intensity processing in other species including humans. If the enhancement effect of zinc nanoparticles observed in vivo are confirmed by future behavioral studies, zinc nanoparticles may provide a way for enhancing the olfactory sensitivity of canines for detection of target substances such as explosives and contraband substances at very low concentrations, which would otherwise go undetected.

  15. Interaction versus Observation: distinctive modes of social cognition in human brain and behavior? A combined fMRI and eye-tracking study.

    Directory of Open Access Journals (Sweden)

    Kristian eTylen

    2012-12-01

    Full Text Available Human cognition has usually been approached on the level of individual minds and brains, but social interaction is a challenging case. Is it best thought of as a self-contained individual cognitive process aiming at an ‘understanding of the other’, or should it rather be approached as an collective, inter-personal process where individual cognitive components interact on a moment-to-moment basis to form coupled dynamics? In a combined fMRI and eye tracking study we directly contrasted these models of social cognition. We found that the perception of situations affording social contingent responsiveness (e.g. someone offering or showing you an object elicited activations in regions of the right posterior temporal sulcus and yielded greater pupil dilation corresponding to a model of coupled dynamics (joint action. In contrast, the social-cognitive perception of someone ‘privately’ manipulating an object elicited activation in medial prefrontal cortex, the right inferior frontal gyrus and right inferior parietal lobus, regions normally associated with Theory of Mind and with the mirror neuron system. Our findings support a distinction in social cognition between social observation and social interaction, and demonstrate that simple ostensive cues may shift participants’ experience, behavior and brain activity between these modes. The identification of a distinct, interactive mode has implications for research on social cognition, both in everyday life and in clinical conditions.

  16. Magnetic Resonance, Functional (fMRI) -- Brain

    Science.gov (United States)

    ... their nature and the strength of the MRI magnet. Many implanted devices will have a pamphlet explaining ... large cylinder-shaped tube surrounded by a circular magnet. You will lie on a moveable examination table ...

  17. Investigating the physiology of brain activation with MRI

    Science.gov (United States)

    Buxton, Richard B.; Uludag, Kamil; Dubowitz, David J.

    2004-04-01

    Functional magnetic resonance imaging (fMRI) has become a powerful tool for investigating the working human brain based on the blood oxygenation level dependent (BOLD) effect on the MR signal. However, despite the widespread use of fMRI techniques for mapping brain activation, the basic physiological mechanisms underlying the observed signal changes are still poorly understood. Arterial spin labeling (ASL) techniques, which measure cerebral blood flow (CBF) and the BOLD effect simultaneously, provide a useful tool for investigating these physiological questions. In this paper, recent results of studies manipulating the baseline CBF both pharmacologically and physiologically will be discussed. These data are consistent with a feed-forward mechanism of neurovascular coupling, and suggest that the CBF change itself may be a more robust reflection of neural activity changes than the BOLD effect. Consistent with these data, a new thermodynamic hypothesis is proposed for the physiological function of CBF regulation: maintenance of the [O2]/[CO2] concentration ratio at the mitochondria in order to preserve the free energy available from oxidative metabolism. A kinetic model based on this hypothesis provides a reasonable quantitative description of the CBF changes associated with neural activity and altered blood gases (CO2 and O2).

  18. Brain regional homogeneity changes following transjugular intrahepatic portosystemic shunt in cirrhotic patients support cerebral adaptability theory—A resting-state functional MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Ling; Qi, Rongfeng [Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002 (China); Zhang, Long Jiang, E-mail: kevinzhlj@163.com [Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002 (China); Zhong, Jianhui [Department of Biomedical Engineering, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Zheng, Gang [Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002 (China); Wu, Xingjiang; Fan, Xinxin [Department of General Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002 (China); Lu, Guang Ming, E-mail: cjr.luguangming@vip.163.com [Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing 210002 (China)

    2014-03-15

    Purpose: The exact neuro-pathophysiological effect of transjugular intrahepatic portosystemic shunt (TIPS) on brain function remains unclear. The purpose of this study was to investigate the longitudinal brain activity changes in cirrhotic patients with TIPS insertion using resting-state functional MRI (fMRI) with regional homogeneity (ReHo) method. Methods: Fifteen cirrhotic patients without overt hepatic encephalopathy (OHE) planned for TIPS procedure and 15 age- and gender-matched healthy controls were included in this study. Eleven of the 15 patients underwent repeated fMRI examinations at median 7-day following TIPS, 8 patients in median 3-month, and 7 patients in median 1-year follow-up duration, respectively. Regional homogeneity was calculated by the Kendall's coefficient of concordance (KCC) and compared between patients before TIPS and healthy controls with two-sample t test as well as pre-and post-TIPS patients with paired t test. Correlations between the pre- and post-TIPS changes of ReHo and the changes of venous blood ammonia level and number connection test type A (NCT-A)/digit symbol test (DST) scores were calculated by crossing subjects. Results: Compared with healthy controls, 15 cirrhotic patients before TIPS procedure showed decreased ReHo in the bilateral frontal, parietal, temporal and occipital lobes and increased ReHo in the bilateral caudate. Compared with the pre-TIPS patients, 11 post-TIPS patients in the median 7-day follow-up examinations demonstrated decreased ReHo in the medial frontal gyrus (MFG), superior parietal gyrus (SPG), middle/superior temporal gyrus (M/STG), anterior cingulate cortex (ACC), caudate, and increased ReHo in the insula. Eight post-TIPS patients in the median 3-month follow-up examinations showed widespread decreased ReHo in the bilateral frontal and parietal lobes, ACC, caudate, and increased ReHo in the insula and precuneus/cuneus. In the median 1-year follow-up studies, seven post-TIPS patients displayed

  19. A quantitative MRI method for imaging blood-brain barrier leakage in experimental traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available Blood-brain barrier (BBB disruption is common following traumatic brain injury (TBI. Dynamic contrast enhanced (DCE MRI can longitudinally measure the transport coefficient Ktrans which reflects BBB permeability. Ktrans measurements however are not widely used in TBI research because it is generally considered to be noisy and possesses low spatial resolution. We improved spatiotemporal resolution and signal sensitivity of Ktrans MRI in rats by using a high-sensitivity surface transceiver coil. To overcome the signal drop off profile of the surface coil, a pre-scan module was used to map the flip angle (B1 field and magnetization (M0 distributions. A series of T1-weighted gradient echo images were acquired and fitted to the extended Kety model with reversible or irreversible leakage, and the best model was selected using F-statistics. We applied this method to study the rat brain one hour following controlled cortical impact (mild to moderate TBI, and observed clear depiction of the BBB damage around the impact regions, which matched that outlined by Evans Blue extravasation. Unlike the relatively uniform T2 contrast showing cerebral edema, Ktrans shows a pronounced heterogeneous spatial profile in and around the impact regions, displaying a nonlinear relationship with T2. This improved Ktrans MRI method is also compatible with the use of high-sensitivity surface coil and the high-contrast two-coil arterial spin-labeling method for cerebral blood flow measurement, enabling more comprehensive investigation of the pathophysiology in TBI.

  20. Differentiating shunt-responsive normal pressure hydrocephalus from Alzheimer disease and normal aging: pilot study using automated MRI brain tissue segmentation.

    Science.gov (United States)

    Serulle, Yafell; Rusinek, Henry; Kirov, Ivan I; Milch, Hannah; Fieremans, Els; Baxter, Alexander B; McMenamy, John; Jain, Rajan; Wisoff, Jeffrey; Golomb, James; Gonen, Oded; George, Ajax E

    2014-10-01

    Evidence suggests that normal pressure hydrocephalus (NPH) is underdiagnosed in day to day radiologic practice, and differentiating NPH from cerebral atrophy due to other neurodegenerative diseases and normal aging remains a challenge. To better characterize NPH, we test the hypothesis that a prediction model based on automated MRI brain tissue segmentation can help differentiate shunt-responsive NPH patients from cerebral atrophy due to Alzheimer disease (AD) and normal aging. Brain segmentation into gray and white matter (GM, WM), and intracranial cerebrospinal fluid was derived from pre-shunt T1-weighted MRI of 15 shunt-responsive NPH patients (9 men, 72.6 ± 8.0 years-old), 17 AD patients (10 men, 72.1 ± 11.0 years-old) chosen as a representative of cerebral atrophy in this age group; and 18 matched healthy elderly controls (HC, 7 men, 69.7 ± 7.0 years old). A multinomial prediction model was generated based on brain tissue volume distributions. GM decrease of 33% relative to HC characterized AD (P normal GM volumes characterized NPH. A multinomial regression model based on gender, GM and ventricular volume had 96.3% accuracy differentiating NPH from AD and HC. In conclusion, automated MRI brain tissue segmentation differentiates shunt-responsive NPH with high accuracy from atrophy due to AD and normal aging. This method may improve diagnosis of NPH and improve our ability to distinguish normal from pathologic aging.

  1. Lying about Facial Recognition: An fMRI Study

    Science.gov (United States)

    Bhatt, S.; Mbwana, J.; Adeyemo, A.; Sawyer, A.; Hailu, A.; VanMeter, J.

    2009-01-01

    Novel deception detection techniques have been in creation for centuries. Functional magnetic resonance imaging (fMRI) is a neuroscience technology that non-invasively measures brain activity associated with behavior and cognition. A number of investigators have explored the utilization and efficiency of fMRI in deception detection. In this study,…

  2. Structural MRI of pediatric brain development: what have we learned and where are we going?

    Science.gov (United States)

    Giedd, Jay N; Rapoport, Judith L

    2010-09-09

    Magnetic resonance imaging (MRI) allows unprecedented access to the anatomy and physiology of the developing brain without the use of ionizing radiation. Over the past two decades, thousands of brain MRI scans from healthy youth and those with neuropsychiatric illness have been acquired and analyzed with respect to diagnosis, sex, genetics, and/or psychological variables such as IQ. Initial reports comparing size differences of various brain components averaged across large age spans have given rise to longitudinal studies examining trajectories of development over time and evaluations of neural circuitry as opposed to structures in isolation. Although MRI is still not of routine diagnostic utility for evaluation of pediatric neuropsychiatric disorders, patterns of typical versus atypical development have emerged that may elucidate pathologic mechanisms and suggest targets for intervention. In this review we summarize general contributions of structural MRI to our understanding of neurodevelopment in health and illness.

  3. Synthetic MRI of the brain in a clinical setting

    Energy Technology Data Exchange (ETDEWEB)

    Blystad, I.; Smedby, O. [Center for Medical Image Science and Visualization, CMIV, Linkoeping University, Linkoeping (Sweden); Radiology, Department of Medical and Health Sciences, Linkoeping University, Department of Radiology, UHL, County Council of Oestergoetland, Linkoeping (Sweden)], E-mail: ida.blystad@lio.se; Warntjes, J.B.M. [Center for Medical Image Science and Visualization, CMIV, Linkoeping University, Linkoeping (Sweden); Clinical Physiology, Department of Medical and Health Sciences, Linkoeping University, Department of Clinical Physiology, UHL, County Council of Oestergoetland, Linkoeping (Sweden); Landtblom, A.-M. [Center for Medical Image Science and Visualization, CMIV, Linkoeping University, Linkoeping (Sweden); Neurology, Department of Clinical and Experimental Medicine, Linkoeping University, Division of Neurology, UHL, LiM, County Council of Oestergoetland, Linkoeping (Sweden); Lundberg, P. [Center for Medical Image Science and Visualization, CMIV, Linkoeping University, Linkoeping (Sweden); Radiation Physics, Department of Medical and Health Sciences, Linkoeping University, Department of Radiation Physics, UHL, County Council of Oestergoetland, Linkoeping (Sweden); Larsson, E.-M. [Center for Medical Image Science and Visualization, CMIV, Linkoeping University, Linkoeping (Sweden); Department of Radiology, Oncology and Radiation Science/Radiology, Uppsala University, Uppsala (Sweden)

    2012-12-15

    Background. Conventional magnetic resonance imaging (MRI) has relatively long scan times for routine examinations, and the signal intensity of the images is related to the specific MR scanner settings. Due to scanner imperfections and automatic optimizations, it is impossible to compare images in terms of absolute image intensity. Synthetic MRI, a method to generate conventional images based on MR quantification, potentially both decreases examination time and enables quantitative measurements. Purpose. To evaluate synthetic MRI of the brain in a clinical setting by assessment of the contrast, the contrast-to-noise ratio (CNR), and the diagnostic quality compared with conventional MR images. Material and Methods. Twenty-two patients had synthetic imaging added to their clinical MR examination. In each patient, 12 regions of interest were placed in the brain images to measure contrast and CNR. Furthermore, general image quality, probable diagnosis, and lesion conspicuity were investigated. Results. Synthetic T1-weighted turbo spin echo and T2-weighted turbo spin echo images had higher contrast but also a higher level of noise, resulting in a similar CNR compared with conventional images. Synthetic T2-weighted FLAIR images had lower contrast and a higher level of noise, which led to a lower CNR. Synthetic images were generally assessed to be of inferior image quality, but agreed with the clinical diagnosis to the same extent as the conventional images. Lesion conspicuity was higher in the synthetic T1-weighted images, which also had a better agreement with the clinical diagnoses than the conventional T1-weighted images. Conclusion. Synthetic MR can potentially shorten the MR examination time. Even though the image quality is perceived to be inferior, synthetic images agreed with the clinical diagnosis to the same extent as the conventional images in this study.

  4. Magnitude Processing in the Brain: An fMRI Study of Time, Space, and Numerosity as a Shared Cortical System

    Science.gov (United States)

    Skagerlund, Kenny; Karlsson, Thomas; Träff, Ulf

    2016-01-01

    Continuous dimensions, such as time, space, and numerosity, have been suggested to be subserved by common neurocognitive mechanisms. Neuroimaging studies that have investigated either one or two dimensions simultaneously have consistently identified neural correlates in the parietal cortex of the brain. However, studies investigating the degree of neural overlap across several dimensions are inconclusive, and it remains an open question whether a potential overlap can be conceptualized as a neurocognitive magnitude processing system. The current functional magnetic resonance imaging study investigated the potential neurocognitive overlap across three dimensions. A sample of adults (N = 24) performed three different magnitude processing tasks: a temporal discrimination task, a number discrimination task, and a line length discrimination task. A conjunction analysis revealed several overlapping neural substrates across multiple magnitude dimensions, and we argue that these cortical nodes comprise a distributed magnitude processing system. Key components of this predominantly right-lateralized system include the intraparietal sulcus, insula, premotor cortex/SMA, and inferior frontal gyrus. Together with previous research highlighting intraparietal sulcus, our results suggest that the insula also is a core component of the magnitude processing system. We discuss the functional role of each of these components in the magnitude processing system and suggest that further research of this system may provide insight into the etiology of neurodevelopmental disorders where cognitive deficits in magnitude processing are manifest. PMID:27761110

  5. MRI and brain spect findings in patients with unilateral temporal lobe epilepsy and normal CT scan

    Directory of Open Access Journals (Sweden)

    P.G. Carrilho

    1994-06-01

    Full Text Available 26 patients with temporal lobe epilepsy clinically documented by several abnormal interictal surface EEGs with typical unitemporal epileptiform activity and a normal CT scan were studied. Interictal99mTC HMPAO brain SPECT and MRI were performed in all subjects. Abnormalities were shown in 61.5% of MRI (n=16 and 65.4% of SPECT (n=17. Hippocampal atrophy associated to a high signal on T2-weighted MRI slices suggesting mesial temporal sclerosis was the main finding (n=12; 75% of abnormal MRI. MRI correlated well to surface EEG in 50% (n=13. There was also a good correlation between MRI and SPECT in 30.7% (n=8. SPECT and EEG were in agreement in 57.7% (n=l5. MRI, SPECT and EEG were congruent in 26.9% (n=7. These results support the usefulness of interictal brain SPECT and MRI in detecting lateralized abnormalities in temporal lobe epilepsy. On the other hand, in two cases, interictal SPECT correlated poorly with surface EEG. This functional method should not be used isolately in the detection of temporal lobe foci. MRI is more useful than CT as a neuroimaging technique in temporal lobe epilepsy. It may detect small structural lesions and mesial temporal lobe sclerosis which are not easily seen with traditional CT scanning.

  6. Cerebral circulation and metabolism in the patients with higher brain dysfunction caused by chronic minor traumatic brain injury. A study by the positron emission tomography in twenty subjects with normal MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Kabasawa, Hidehiro; Ogawa, Tetsuo; Iida, Akihiko; Matsubara, Michitaka [Nagoya City Rehabilitation and Sports Center (Japan)

    2002-06-01

    Many individuals are affected on their higher brain functions, such as intelligence, memory, and attention, even after minor traumatic brain injury (MTBI). Although higher brain dysfunction is based on impairment of the cerebral circulation and metabolism, the precise relationship between them remains unknown. This study was undertaken to investigate the relationship between the cerebral circulation or cerebral metabolism and higher brain dysfunction. Twenty subjects with higher brain dysfunction caused by chronic MTBI were studied. They had no abnormal MRI findings. The full-scale intelligence quotient (FIQ) were quantitatively evaluated by the Wechsler Adult Intelligence Scale-Revised (WAIS-R), and the subjects were classified into the normal group and the impaired group. Concurrent with the evaluation of FIQ, positron emission tomography (PET) was performed by the steady state method with {sup 15}O gases inhalation. Regional cerebral blood flow (rCBF), oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) were calculated in the bilateral frontal, parietal, temporal, and occipital lobe. First, of all twenty subjects, we investigated rCBF, OEF and CMRO{sub 2} in all regions. Then we compared rCBF, OEF, and CMRO{sub 2} between the normal group and the impaired group based on FIQ score. We also studied the change of FIQ score of 13 subjects 9.3 months after the first evaluation. In addition, we investigated the change of rCBF, OEF and CMRO{sub 2} along with the improvement of FIQ score. Although rCBF and OEF of all subjects were within the normal range in all regions, CMRO{sub 2} of more than half of subjects was under the lower normal limit in all regions except in the right occipital lobe, showing the presence of ''relative luxury perfusion''. Comparison of rCBF, OEF and CMRO{sub 2} between normal group and impaired group revealed that CMRO{sub 2} of the impaired group was significantly lower than that of the

  7. How does language distance between L1 and L2 affect the L2 brain network? An fMRI study of Korean-Chinese-English trilinguals.

    Science.gov (United States)

    Kim, Say Young; Qi, Ting; Feng, Xiaoxia; Ding, Guosheng; Liu, Li; Cao, Fan

    2016-04-01

    The present study tested the hypothesis that language distance between first language (L1) and second language (L2) influences the assimilation and accommodation pattern in Korean-Chinese-English trilinguals. The distance between English and Korean is smaller than that between Chinese and Korean in terms of orthographic transparency, because both English and Korean are alphabetic, whereas Chinese is logographic. During fMRI, Korean trilingual participants performed a visual rhyming judgment task in three languages (Korean: KK, Chinese: KC, English: KE). Two L1 control groups were native Chinese and English speakers performing the task in their native languages (CC and EE, respectively). The general pattern of brain activation of KC was more similar to that of CC than KK, suggesting accommodation. Higher accuracy in KC was associated with decreased activation in regions of the KK network, suggesting reduced assimilation. In contrast, the brain activation of KE was more similar to that of KK than EE, suggesting assimilation. Higher accuracy in KE was associated with decreased activation in regions of the EE network, suggesting reduced accommodation. Finally, an ROI analysis on the left middle frontal gyrus revealed greater activation for KC than for KE, suggesting its selective involvement in the L2 with more arbitrary mapping between orthography and phonology (i.e., Chinese). Taken together, the brain network involved in L2 reading is similar to the L1 network when L2 and L1 are similar in orthographic transparency, while significant accommodation is expected when L2 is more opaque than L1.

  8. Neural reactivity to visual food stimuli is reduced in some areas of the brain during evening hours compared to morning hours: an fMRI study in women.

    Science.gov (United States)

    Masterson, Travis D; Kirwan, C Brock; Davidson, Lance E; LeCheminant, James D

    2016-03-01

    The extent that neural responsiveness to visual food stimuli is influenced by time of day is not well examined. Using a crossover design, 15 healthy women were scanned using fMRI while presented with low- and high-energy pictures of food, once in the morning (6:30-8:30 am) and once in the evening (5:00-7:00 pm). Diets were identical on both days of the fMRI scans and were verified using weighed food records. Visual analog scales were used to record subjective perception of hunger and preoccupation with food prior to each fMRI scan. Six areas of the brain showed lower activation in the evening to both high- and low-energy foods, including structures in reward pathways (P foods compared to low-energy foods (P food stimuli tended to produce greater fMRI responses than low-energy food stimuli in specific areas of the brain, regardless of time of day. However, evening scans showed a lower response to both low- and high-energy food pictures in some areas of the brain. Subjectively, participants reported no difference in hunger by time of day (F = 1.84, P = 0.19), but reported they could eat more (F = 4.83, P = 0.04) and were more preoccupied with thoughts of food (F = 5.51, P = 0.03) in the evening compared to the morning. These data underscore the role that time of day may have on neural responses to food stimuli. These results may also have clinical implications for fMRI measurement in order to prevent a time of day bias.

  9. Effect of tolperisone on the resting brain and on evoked responses, an phMRI BOLD study.

    Science.gov (United States)

    Kocsis, Pál; Gajári, Dávid; Deli, Levente; Gőcze, Krisztina Zsedrovitsné; Pozsgay, Zsófia; Tihanyi, Károly

    2013-10-01

    Tolperisone is a voltage gated sodium channel blocker, centrally acting muscle relaxant drug, with a very advantageous side effect profile. Like other sodium channel blockers, it has weak affinity to the resting state and high affinity to the open/inactivated state of the channel. In this paper, its effect on BOLD responses in rat brain were elucidated both on the resting brain and paw stimulation evoked BOLD responses. Tolperisone did not exert any visible effect on resting brain, but strongly inhibited the paw stimulation evoked BOLD responses, showing somewhat higher efficacy in brain areas involved in pain sensation. This finding is in a good agreement with its sodium channel blocking profile. In the resting brain, most of the channels are in resting state. Electric train stimuli of the paw results in over activated neurons, where most sodium channels are in open or inactivated state. These data suggest that the very advantageous profile of tolperisone can be explained by its selective action on open or inactivated sodium channels of over-activated neurons in various brain regions rather than by a selective effect in the spinal cord as suggested previously.

  10. MRI quantitative hemodynamic evaluation of the brain

    NARCIS (Netherlands)

    De Vis, J.B.; Mali, W.P.T.M.; Hendrikse, J.; Petersen, E.T.

    2015-01-01

    The cerebral blood flow (CBF) or the delivery of nutrients to the brain tissue is essential for the viability of brain cells and is a necessity for the human body to perform physical and mental activities. Both under-and overperfusion of the brain tissue can cause substantial harm wherefore the CBF

  11. Imaging the premature brain: ultrasound or MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Vries, Linda S. de; Benders, Manon J.N.L.; Groenendaal, Floris [UMC Utrecht, Department of Neonatology, Wilhelmina Children' s Hospital, PO Box 85090, Utrecht (Netherlands)

    2013-09-15

    Neuroimaging of preterm infants has become part of routine clinical care, but the question is often raised on how often cranial ultrasound should be done and whether every high risk preterm infant should at least have one MRI during the neonatal period. An increasing number of centres perform an MRI either at discharge or around term equivalent age, and a few centres have access to a magnet in or adjacent to the neonatal intensive care unit and are doing sequential MRIs. In this review, we try to discuss when best to perform these two neuroimaging techniques and the additional information each technique may provide. (orig.)

  12. Calcitonin Gene-Related Peptide Modulates Heat Nociception in the Human Brain - An fMRI Study in Healthy Volunteers

    DEFF Research Database (Denmark)

    Asghar, Mohammad Sohail; Becerra, Lino; Larsson, Henrik B W

    2016-01-01

    BACKGROUND: Intravenous infusion of calcitonin-gene-related-peptide (CGRP) provokes headache and migraine in humans. Mechanisms underlying CGRP-induced headache are not fully clarified and it is unknown to what extent CGRP modulates nociceptive processing in the brain. To elucidate this we record...... cortex. Sumatriptan injection reversed these changes. CONCLUSION: The changes in BOLD-signals in the brain after CGRP infusion suggests that systemic CGRP modulates nociceptive transmission in the trigeminal pain pathways in response to noxious heat stimuli.......BACKGROUND: Intravenous infusion of calcitonin-gene-related-peptide (CGRP) provokes headache and migraine in humans. Mechanisms underlying CGRP-induced headache are not fully clarified and it is unknown to what extent CGRP modulates nociceptive processing in the brain. To elucidate this we recorded...

  13. Structural and Functional Brain Remodeling during Pregnancy with Diffusion Tensor MRI and Resting-State Functional MRI.

    Directory of Open Access Journals (Sweden)

    Russell W Chan

    Full Text Available Although pregnancy-induced hormonal changes have been shown to alter the brain at the neuronal level, the exact effects of pregnancy on brain at the tissue level remain unclear. In this study, diffusion tensor imaging (DTI and resting-state functional MRI (rsfMRI were employed to investigate and document the effects of pregnancy on the structure and function of the brain tissues. Fifteen Sprague-Dawley female rats were longitudinally studied at three days before mating (baseline and seventeen days after mating (G17. G17 is equivalent to the early stage of the third trimester in humans. Seven age-matched nulliparous female rats served as non-pregnant controls and were scanned at the same time-points. For DTI, diffusivity was found to generally increase in the whole brain during pregnancy, indicating structural changes at microscopic levels that facilitated water molecular movement. Regionally, mean diffusivity increased more pronouncedly in the dorsal hippocampus while fractional anisotropy in the dorsal dentate gyrus increased significantly during pregnancy. For rsfMRI, bilateral functional connectivity in the hippocampus increased significantly during pregnancy. Moreover, fractional anisotropy increase in the dentate gyrus appeared to correlate with the bilateral functional connectivity increase in the hippocampus. These findings revealed tissue structural modifications in the whole brain during pregnancy, and that the hippocampus was structurally and functionally remodeled in a more marked manner.

  14. Structural and Functional Brain Remodeling during Pregnancy with Diffusion Tensor MRI and Resting-State Functional MRI.

    Science.gov (United States)

    Chan, Russell W; Ho, Leon C; Zhou, Iris Y; Gao, Patrick P; Chan, Kevin C; Wu, Ed X

    2015-01-01

    Although pregnancy-induced hormonal changes have been shown to alter the brain at the neuronal level, the exact effects of pregnancy on brain at the tissue level remain unclear. In this study, diffusion tensor imaging (DTI) and resting-state functional MRI (rsfMRI) were employed to investigate and document the effects of pregnancy on the structure and function of the brain tissues. Fifteen Sprague-Dawley female rats were longitudinally studied at three days before mating (baseline) and seventeen days after mating (G17). G17 is equivalent to the early stage of the third trimester in humans. Seven age-matched nulliparous female rats served as non-pregnant controls and were scanned at the same time-points. For DTI, diffusivity was found to generally increase in the whole brain during pregnancy, indicating structural changes at microscopic levels that facilitated water molecular movement. Regionally, mean diffusivity increased more pronouncedly in the dorsal hippocampus while fractional anisotropy in the dorsal dentate gyrus increased significantly during pregnancy. For rsfMRI, bilateral functional connectivity in the hippocampus increased significantly during pregnancy. Moreover, fractional anisotropy increase in the dentate gyrus appeared to correlate with the bilateral functional connectivity increase in the hippocampus. These findings revealed tissue structural modifications in the whole brain during pregnancy, and that the hippocampus was structurally and functionally remodeled in a more marked manner.

  15. Expertise modulates local regional homogeneity of spontaneous brain activity in the resting brain: an fMRI study using the model of skilled acupuncturists.

    Science.gov (United States)

    Dong, Minghao; Qin, Wei; Zhao, Ling; Yang, Xuejuan; Yuan, Kai; Zeng, Fang; Sun, Jinbo; Yu, Dahua; von Deneen, Karen M; Liang, Fanrong; Tian, Jie

    2014-03-01

    Studies on training/expertise-related effects on human brain in context of neuroplasticity have revealed that plastic changes modulate not only task activations but also patterns and strength of internetworks and intranetworks functional connectivity in the resting state. Much has known about plastic changes in resting state on global level; however, how training/expertise-related effect affects patterns of local spontaneous activity in resting brain remains elusive. We investigated the homogeneity of local blood oxygen level-dependent fluctuations in the resting state using a regional homogeneity (ReHo) analysis among 16 acupuncturists and 16 matched nonacupuncturists (NA). To prove acupuncturists' expertise, we used a series of psychophysical tests. Our results demonstrated that, acupuncturists significantly outperformed NA in tactile-motor and emotional regulation domain and the acupuncturist group showed increased coherence in local BOLD signal fluctuations in the left primary motor cortex (MI), the left primary somatosensory cortex (SI) and the left ventral medial prefrontal cortex/orbitofrontal cortex (VMPFC/OFC). Regression analysis displayed that, in the acupuncturists group, ReHo of VMPFC/OFC could predict behavioral outcomes, evidenced by negative correlation between unpleasantness ratings and ReHo of VMPFC/OFC and ReHo of SI and MI positively correlated with the duration of acupuncture practice. We suggest that expertise could modulate patterns of local resting state activity by increasing regional clustering strength, which is likely to contribute to advanced local information processing efficiency. Our study completes the understanding of neuroplasticity changes by adding the evidence of local resting state activity alterations, which is helpful for elucidating in what manner training effect extends beyond resting state.

  16. Developmental differences in the brain response to unhealthy food cues : An fMRI study of children and adults

    NARCIS (Netherlands)

    van Meer, Floor; van der Laan, Laura N; Charbonnier, Lisette; Viergever, Max A; Adan, Roger Ah; Smeets, Paul Am

    2016-01-01

    BACKGROUND: Food cues are omnipresent and may trigger overconsumption. In the past 2 decades, the prevalence of childhood obesity has increased dramatically. Because children's brains are still developing, especially in areas important for inhibition, children may be more susceptible than adults to

  17. Incidental use of ecstasy: no evidence for harmful effects on cognitive brain function in a prospective fMRI study

    NARCIS (Netherlands)

    Jager, G.; Win, M.M. de; Vervaeke, H.K.; Schilt, T.; Kahn, R.S.; Brink, W. van den; Ree, J.M. van; Ramsey, M.F.

    2007-01-01

    Rationale Heavy ecstasy use in humans has been associated with cognitive impairments and changes in cognitive brain function supposedly due to damage to the serotonin system. There is concern that even a single dose of 3,4-methylenedioxymethamphetamine may be neurotoxic, but very little is known ab

  18. Structural and Functional Brain Repair Studies of PD Models by Novel Neurosurgical, PET and MRI/MRS Methods

    Science.gov (United States)

    1999-09-01

    Isacson O. and Björklund A. (1988) Trophic effects on cholinergic striatal interneurones by submaxillary gland transplants. Prog. Brain Res. 78,409-413...Uhler, T.A., Short, M.P., Ezzedine, Z.D., Klagsbrun, M., Breakefield, X.O. and Isacson, O. (1993) Effects of biologically delivered NGF, BDNF , and

  19. Joint brain connectivity estimation from diffusion and functional MRI data

    Science.gov (United States)

    Chu, Shu-Hsien; Lenglet, Christophe; Parhi, Keshab K.

    2015-03-01

    Estimating brain wiring patterns is critical to better understand the brain organization and function. Anatomical brain connectivity models axonal pathways, while the functional brain connectivity characterizes the statistical dependencies and correlation between the activities of various brain regions. The synchronization of brain activity can be inferred through the variation of blood-oxygen-level dependent (BOLD) signal from functional MRI (fMRI) and the neural connections can be estimated using tractography from diffusion MRI (dMRI). Functional connections between brain regions are supported by anatomical connections, and the synchronization of brain activities arises through sharing of information in the form of electro-chemical signals on axon pathways. Jointly modeling fMRI and dMRI data may improve the accuracy in constructing anatomical connectivity as well as functional connectivity. Such an approach may lead to novel multimodal biomarkers potentially able to better capture functional and anatomical connectivity variations. We present a novel brain network model which jointly models the dMRI and fMRI data to improve the anatomical connectivity estimation and extract the anatomical subnetworks associated with specific functional modes by constraining the anatomical connections as structural supports to the functional connections. The key idea is similar to a multi-commodity flow optimization problem that minimizes the cost or maximizes the efficiency for flow configuration and simultaneously fulfills the supply-demand constraint for each commodity. In the proposed network, the nodes represent the grey matter (GM) regions providing brain functionality, and the links represent white matter (WM) fiber bundles connecting those regions and delivering information. The commodities can be thought of as the information corresponding to brain activity patterns as obtained for instance by independent component analysis (ICA) of fMRI data. The concept of information

  20. 正常成人松果体MRI研究%MRI imaging studies of pineal gland in normal human brain

    Institute of Scientific and Technical Information of China (English)

    邓玲; 钱学华; 周庭永; 刘敏; 白桂芹; 吕发金

    2015-01-01

    Objective To establish the parameter standard of pineal gland and discuss the changing rule of different groups by gender and age in health adults on MRI. Methods A total of 327 adult heads were scanned by using 3D MR sequences,pineal gland and its related structures were observed and analyzed. Results The length of the pineal gland was(7.12±1.11)mm in the female group,and (6.52±1.01) mm in the male group(female>male,Pmale,P男性,P男性,P<0.05)。结论松果体矢径和体积女性大于男性,松果体体积性别差异出现在31~60岁。

  1. Lesion Activity on Brain MRI in a Chinese Population with Unilateral Optic Neuritis.

    Science.gov (United States)

    Lai, Chuntao; Chang, Qinglin; Tian, Guohong; Wang, Jiawei; Yin, Hongxia; Liu, Wu

    2015-01-01

    Longitudinal studies have shown that brain white matter lesions are strong predictors of the conversion of unilateral optic neuritis to multiple sclerosis (MS) in Caucasian populations. Consequently brain MRI criteria have been developed to improve the prediction of the development of clinically definite multiple sclerosis (CDMS). In Asian populations, optic neuritis may be the first sign of classical or optic-spinal MS. These signs add to the uncertainty regarding brain MRI changes with respect to the course of unilateral optic neuritis. The aim of this study was to examine the association between brain lesion activity and conversion to CDMS in Chinese patients with unilateral optic neuritis. A small prospective cohort study of 40 consecutive Chinese patients who presented with unilateral optic neuritis was conducted. Brain lesion activity was recorded as the incidence of Gd-enhanced lesions and new T2 lesions. Brain lesions on MRI that were characteristic of MS were defined according to the 2010 revisions of the McDonald criteria. The primary endpoint was the development of CDMS. We found that nineteen patients (48%) had brain lesions that were characteristic of MS on the initial scan. One of these patients (3%) had Gd-enhanced brain lesions. A significantly lower percentage of the patients (10%, poptic neuritis; however, these patients exhibit low lesion activity. The predictive value of brain lesion activity for CDMS requires investigation in additional patients.

  2. Age-related alterations of brain network underlying the retrieval of emotional autobiographical memories: An fMRI study using independent component analysis

    Directory of Open Access Journals (Sweden)

    Ruiyang eGe

    2014-08-01

    Full Text Available Normal aging has been shown to modulate the neural underpinnings of autobiographical memory and emotion processing. Moreover, previous researches have suggested that aging produces a positivity effect in autobiographical memory. Although a few imaging studies have investigated the neural mechanism of the positivity effect, the neural substrates underlying the positivity effect in emotional autobiographical memory is unclear. To understand the age-related neural changes in emotional autobiographical memory that underlie the positivity effect, the present functional magnetic resonance imaging (fMRI study used the independent component analysis (ICA method to compare brain networks in younger and older adults as they retrieved positive and negative autobiographical events. Compared to their younger counterparts, older adults reported relatively higher positive feelings when retrieving emotional autobiographical events. Imaging data indicated an age-related reversal within the ventromedial prefrontal/anterior cingulate cortex (VMPFC/ACC and the left amygdala of the brain networks that were engaged in the retrieval of autobiographical events with different valence. The retrieval of negative events compared to positive events induced stronger activity in the VMPFC/ACC and weaker activity in the amygdala for the older adults, whereas the younger adults showed a reversed pattern. Moreover, activity in the VMPFC/ACC within the task-related networks showed a negative correlation with the emotional valence intensity. These results may suggest that the positivity effect in older adults’ autobiographical memories is potentially due to age-related changes in controlled emotional processing implemented by the VMPFC/ACC-amygdala circuit.

  3. Spontaneous Slow Fluctuation of EEG Alpha Rhythm Reflects Activity in Deep-Brain Structures: A Simultaneous EEG-fMRI Study.

    Directory of Open Access Journals (Sweden)

    Kei Omata

    Full Text Available The emergence of the occipital alpha rhythm on brain electroencephalogram (EEG is associated with brain activity in the cerebral neocortex and deep brain structures. To further understand the mechanisms of alpha rhythm power fluctuation, we performed simultaneous EEGs and functional magnetic resonance imaging recordings in human subjects during a resting state and explored the dynamic relationship between alpha power fluctuation and blood oxygenation level-dependent (BOLD signals of the brain. Based on the frequency characteristics of the alpha power time series (APTS during 20-minute EEG recordings, we divided the APTS into two components: fast fluctuation (0.04-0.167 Hz and slow fluctuation (0-0.04 Hz. Analysis of the correlation between the MRI signal and each component revealed that the slow fluctuation component of alpha power was positively correlated with BOLD signal changes in the brain stem and the medial part of the thalamus and anterior cingulate cortex, while the fast fluctuation component was correlated with the lateral part of the thalamus and the anterior cingulate cortex, but not the brain stem. In summary, these data suggest that different subcortical structures contribute to slow and fast modulations of alpha spectra on brain EEG.

  4. Robust brain parcellation using sparse representation on resting-state fMRI.

    Science.gov (United States)

    Zhang, Yu; Caspers, Svenja; Fan, Lingzhong; Fan, Yong; Song, Ming; Liu, Cirong; Mo, Yin; Roski, Christian; Eickhoff, Simon; Amunts, Katrin; Jiang, Tianzi

    2015-11-01

    Resting-state fMRI (rs-fMRI) has been widely used to segregate the brain into individual modules based on the presence of distinct connectivity patterns. Many parcellation methods have been proposed for brain parcellation using rs-fMRI, but their results have been somewhat inconsistent, potentially due to various types of noise. In this study, we provide a robust parcellation method for rs-fMRI-based brain parcellation, which constructs a sparse similarity graph based on the sparse representation coefficients of each seed voxel and then uses spectral clustering to identify distinct modules. Both the local time-varying BOLD signals and whole-brain connectivity patterns may be used as features and yield similar parcellation results. The robustness of our method was tested on both simulated and real rs-fMRI datasets. In particular, on simulated rs-fMRI data, sparse representation achieved good performance across different noise levels, including high accuracy of parcellation and high robustness to noise. On real rs-fMRI data, stable parcellation of the medial frontal cortex (MFC) and parietal operculum (OP) were achieved on three different datasets, with high reproducibility within each dataset and high consistency across these results. Besides, the parcellation of MFC was little influenced by the degrees of spatial smoothing. Furthermore, the consistent parcellation of OP was also well corresponding to cytoarchitectonic subdivisions and known somatotopic organizations. Our results demonstrate a new promising approach to robust brain parcellation using resting-state fMRI by sparse representation.

  5. Impact of the resolution of brain parcels on connectome-wide association studies in fMRI.

    Science.gov (United States)

    Bellec, Pierre; Benhajali, Yassine; Carbonell, Felix; Dansereau, Christian; Albouy, Geneviève; Pelland, Maxime; Craddock, Cameron; Collignon, Oliver; Doyon, Julien; Stip, Emmanuel; Orban, Pierre

    2015-12-01

    A recent trend in functional magnetic resonance imaging is to test for association of clinical disorders with every possible connection between selected brain parcels. We investigated the impact of the resolution of functional brain parcels, ranging from large-scale networks to local regions, on a mass univariate general linear model (GLM) of connectomes. For each resolution taken independently, the Benjamini-Hochberg procedure controlled the false-discovery rate (FDR) at nominal level on realistic simulations. However, the FDR for tests pooled across all resolutions could be inflated compared to the FDR within resolution. This inflation was severe in the presence of no or weak effects, but became negligible for strong effects. We thus developed an omnibus test to establish the overall presence of true discoveries across all resolutions. Although not a guarantee to control the FDR across resolutions, the omnibus test may be used for descriptive analysis of the impact of resolution on a GLM analysis, in complement to a primary analysis at a predefined single resolution. On three real datasets with significant omnibus test (schizophrenia, congenital blindness, motor practice), markedly higher rate of discovery were obtained at low resolutions, below 50, in line with simulations showing increase in sensitivity at such resolutions. This increase in discovery rate came at the cost of a lower ability to localize effects, as low resolution parcels merged many different brain regions together. However, with 30 or more parcels, the statistical effect maps were biologically plausible and very consistent across resolutions. These results show that resolution is a key parameter for GLM-connectome analysis with FDR control, and that a functional brain parcellation with 30 to 50 parcels may lead to an accurate summary of full connectome effects with good sensitivity in many situations.

  6. In-vivo human brain molecular imaging with a brain-dedicated PET/MRI system.

    Science.gov (United States)

    Cho, Zang Hee; Son, Young Don; Choi, Eun Jung; Kim, Hang Keun; Kim, Jeong Hee; Lee, Sang Yoon; Ogawa, Seiji; Kim, Young Bo

    2013-02-01

    Advances in the new-generation of ultra-high-resolution, brain-dedicated positron emission tomography-magnetic resonance imaging (PET/MRI) systems have begun to provide many interesting insights into the molecular dynamics of the brain. First, the finely delineated structural information from ultra-high-field MRI can help us to identify accurate landmark structures, thereby making it easier to locate PET activation sites that are anatomically well-correlated with metabolic or ligand-specific organs in the neural structures in the brain. This synergistic potential of PET/MRI imaging is discussed in terms of neuroscience and neurological research from both translational and basic research perspectives. Experimental results from the hippocampus, thalamus, and brainstem obtained with (18)F-fluorodeoxyglucose and (11)C-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)benzonitrile are used to demonstrate the potential of this new brain PET/MRI system.

  7. Simultaneous MRI and PET imaging of a rat brain

    Science.gov (United States)

    Raylman, Raymond R.; Majewski, Stan; Lemieux, Susan K.; Sendhil Velan, S.; Kross, Brian; Popov, Vladimir; Smith, Mark F.; Weisenberger, Andrew G.; Zorn, Carl; Marano, Gary D.

    2006-12-01

    Multi-modality imaging is rapidly becoming a valuable tool in the diagnosis of disease and in the development of new drugs. Functional images produced with PET fused with anatomical structure images created by MRI will allow the correlation of form with function. Our group is developing a system to acquire MRI and PET images contemporaneously. The prototype device consists of two opposed detector heads, operating in coincidence mode. Each MRI-PET detector module consists of an array of LSO detector elements coupled through a long fibre optic light guide to a single Hamamatsu flat panel position-sensitive photomultiplier tube (PSPMT). The use of light guides allows the PSPMTs to be positioned outside the bore of a 3T MRI scanner where the magnetic field is relatively small. To test the device, simultaneous MRI and PET images of the brain of a male Sprague Dawley rat injected with FDG were successfully obtained. The images revealed no noticeable artefacts in either image set. Future work includes the construction of a full ring PET scanner, improved light guides and construction of a specialized MRI coil to permit higher quality MRI imaging.

  8. Simultaneous MRI and PET imaging of a rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Raylman, Raymond R [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Majewski, Stan [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Lemieux, Susan K [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Velan, S Sendhil [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States); Kross, Brian [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Popov, Vladimir [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Smith, Mark F [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Weisenberger, Andrew G [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Zorn, Carl [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA (United States); Marano, Gary D [Center for Advanced Imaging, Department of Radiology, Box 9236, West Virginia University, Morgantown, WV (United States)

    2006-12-21

    Multi-modality imaging is rapidly becoming a valuable tool in the diagnosis of disease and in the development of new drugs. Functional images produced with PET fused with anatomical structure images created by MRI will allow the correlation of form with function. Our group is developing a system to acquire MRI and PET images contemporaneously. The prototype device consists of two opposed detector heads, operating in coincidence mode. Each MRI-PET detector module consists of an array of LSO detector elements coupled through a long fibre optic light guide to a single Hamamatsu flat panel position-sensitive photomultiplier tube (PSPMT). The use of light guides allows the PSPMTs to be positioned outside the bore of a 3T MRI scanner where the magnetic field is relatively small. To test the device, simultaneous MRI and PET images of the brain of a male Sprague Dawley rat injected with FDG were successfully obtained. The images revealed no noticeable artefacts in either image set. Future work includes the construction of a full ring PET scanner, improved light guides and construction of a specialized MRI coil to permit higher quality MRI imaging.

  9. Novel whole brain segmentation and volume estimation using quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    West, J. [Linkoeping University, Radiation Physics, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); SyntheticMR AB, Linkoeping (Sweden); Warntjes, J.B.M. [Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); SyntheticMR AB, Linkoeping (Sweden); Linkoeping University and Department of Clinical Physiology UHL, County Council of Oestergoetland, Clinical Physiology, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Lundberg, P. [Linkoeping University, Center for Medical Imaging Science and Visualization (CMIV), Linkoeping (Sweden); Linkoeping University and Department of Radiation Physics UHL, County Council of Oestergoetland, Radiation Physics, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden); Linkoeping University and Department of Radiology UHL, County Council of Oestergoetland, Radiology, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping (Sweden)

    2012-05-15

    Brain segmentation and volume estimation of grey matter (GM), white matter (WM) and cerebro-spinal fluid (CSF) are important for many neurological applications. Volumetric changes are observed in multiple sclerosis (MS), Alzheimer's disease and dementia, and in normal aging. A novel method is presented to segment brain tissue based on quantitative magnetic resonance imaging (qMRI) of the longitudinal relaxation rate R{sub 1}, the transverse relaxation rate R{sub 2} and the proton density, PD. Previously reported qMRI values for WM, GM and CSF were used to define tissues and a Bloch simulation performed to investigate R{sub 1}, R{sub 2} and PD for tissue mixtures in the presence of noise. Based on the simulations a lookup grid was constructed to relate tissue partial volume to the R{sub 1}-R{sub 2}-PD space. The method was validated in 10 healthy subjects. MRI data were acquired using six resolutions and three geometries. Repeatability for different resolutions was 3.2% for WM, 3.2% for GM, 1.0% for CSF and 2.2% for total brain volume. Repeatability for different geometries was 8.5% for WM, 9.4% for GM, 2.4% for CSF and 2.4% for total brain volume. We propose a new robust qMRI-based approach which we demonstrate in a patient with MS. (orig.)

  10. MRI of fetal acquired brain lesions

    Energy Technology Data Exchange (ETDEWEB)

    Prayer, Daniela [Department of Radiodiagnostics, Medical University of Vienna (Austria)]. E-mail: daniela.prayer@meduniwien.ac.at; Brugger, Peter C. [Center of Anatomy and Cell Biology, Medical University of Vienna (Austria); Kasprian, Gregor [Department of Radiodiagnostics, Medical University of Vienna (Austria); Witzani, Linde [Department of Radiodiagnostics, Medical University of Vienna (Austria); Helmer, Hanns [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Dietrich, Wolfgang [Department of Neurosurgery, Medical University of Vienna (Austria); Eppel, Wolfgang [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria); Langer, Martin [Department of Obstetrics and Gynecology, Medical University of Vienna (Austria)

    2006-02-15

    Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images.

  11. Wilson's disease: two treatment modalities. Correlations to pretreatment and posttreatment brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Leiros da Costa, Maria do Desterro [Federal University of Paraiba, Movement Disorders Unit, Paraiba (Brazil); Spitz, Mariana; Bacheschi, Luiz Alberto; Barbosa, Egberto Reis [University of Sao Paulo, Movement Disorders Unit, Sao Paulo (Brazil); Leite, Claudia Costa; Lucato, Leandro Tavares [University of Sao Paulo, Department of Radiology, Sao Paulo (Brazil)

    2009-10-15

    Brain magnetic resonance imaging (MRI) studies on Wilson's disease (WD) show lack of correlations between neurological and neuroimaging features. Long-term follow-up reports with sequential brain MRI in patients with neurological WD comparing different modalities of treatment are scarce. Eighteen patients with neurological WD underwent pretreatment and posttreatment brain MRI scans to evaluate the range of abnormalities and the evolution along these different periods. All patients underwent at least two MRI scans at different intervals, up to 11 years after the beginning of treatment. MRI findings were correlated with clinical picture, clinical severity, duration of neurological symptoms, and treatment with two different drugs. Patients were divided into two groups according to treatment: d-penicillamine (D-P), zinc (Zn), and Zn after the onset of severe intolerance to D-P. MRI scans before treatment showed, in all patients, hypersignal intensity lesions on T2- and proton-density-weighted images bilaterally and symmetrically at basal nuclei, thalamus, brain stem, cerebellum, brain cortex, and brain white matter. The most common neurological symptoms were: dysarthria, parkinsonism, dystonia, tremor, psychiatric disturbances, dysphagia, risus sardonicus, ataxia, chorea, and athetosis. From the neurological point of view, there was no difference on the evolution between the group treated exclusively with D-P and the one treated with Zn. Analysis of MRI scans with longer intervals after the beginning of treatment depicted a trend for neuroimaging worsening, without neurological correspondence, among patients treated with Zn. Neuroimaging pattern of evolution was more favorable for the group that received exclusively D-P. (orig.)

  12. Decoding lifespan changes of the human brain using resting-state functional connectivity MRI.

    Directory of Open Access Journals (Sweden)

    Lubin Wang

    Full Text Available The development of large-scale functional brain networks is a complex, lifelong process that can be investigated using resting-state functional connectivity MRI (rs-fcMRI. In this study, we aimed to decode the developmental dynamics of the whole-brain functional network in seven decades (8-79 years of the human lifespan. We first used parametric curve fitting to examine linear and nonlinear age effect on the resting human brain, and then combined manifold learning and support vector machine methods to predict individuals' "brain ages" from rs-fcMRI data. We found that age-related changes in interregional functional connectivity exhibited spatially and temporally specific patterns. During brain development from childhood to senescence, functional connections tended to linearly increase in the emotion system and decrease in the sensorimotor system; while quadratic trajectories were observed in functional connections related to higher-order cognitive functions. The complex patterns of age effect on the whole-brain functional network could be effectively represented by a low-dimensional, nonlinear manifold embedded in the functional connectivity space, which uncovered the inherent structure of brain maturation and aging. Regression of manifold coordinates with age further showed that the manifold representation extracted sufficient information from rs-fcMRI data to make prediction about individual brains' functional development levels. Our study not only gives insights into the neural substrates that underlie behavioral and cognitive changes over age, but also provides a possible way to quantitatively describe the typical and atypical developmental progression of human brain function using rs-fcMRI.

  13. Biomarkers, designs, and interpretations of resting-state fMRI in translational pharmacological research: A review of state-of-the-Art, challenges, and opportunities for studying brain chemistry.

    Science.gov (United States)

    Khalili-Mahani, Najmeh; Rombouts, Serge A R B; van Osch, Matthias J P; Duff, Eugene P; Carbonell, Felix; Nickerson, Lisa D; Becerra, Lino; Dahan, Albert; Evans, Alan C; Soucy, Jean-Paul; Wise, Richard; Zijdenbos, Alex P; van Gerven, Joop M

    2017-04-01

    A decade of research and development in resting-state functional MRI (RSfMRI) has opened new translational and clinical research frontiers. This review aims to bridge between technical and clinical researchers who seek reliable neuroimaging biomarkers for studying drug interactions with the brain. About 85 pharma-RSfMRI studies using BOLD signal (75% of all) or arterial spin labeling (ASL) were surveyed to investigate the acute effects of psychoactive drugs. Experimental designs and objectives include drug fingerprinting dose-response evaluation, biomarker validation and calibration, and translational studies. Common biomarkers in these studies include functional connectivity, graph metrics, cerebral blood flow and the amplitude and spectrum of BOLD fluctuations. Overall, RSfMRI-derived biomarkers seem to be sensitive to spatiotemporal dynamics of drug interactions with the brain. However, drugs cause both central and peripheral effects, thus exacerbate difficulties related to biological confounds, structured noise from motion and physiological confounds, as well as modeling and inference testing. Currently, these issues are not well explored, and heterogeneities in experimental design, data acquisition and preprocessing make comparative or meta-analysis of existing reports impossible. A unifying collaborative framework for data-sharing and data-mining is thus necessary for investigating the commonalities and differences in biomarker sensitivity and specificity, and establishing guidelines. Multimodal datasets including sham-placebo or active control sessions and repeated measurements of various psychometric, physiological, metabolic and neuroimaging phenotypes are essential for pharmacokinetic/pharmacodynamic modeling and interpretation of the findings. We provide a list of basic minimum and advanced options that can be considered in design and analyses of future pharma-RSfMRI studies. Hum Brain Mapp 38:2276-2325, 2017. © 2017 Wiley Periodicals, Inc.

  14. What can the brain teach us about winemaking? An fMRI study of alcohol level preferences.

    Directory of Open Access Journals (Sweden)

    Ram Frost

    Full Text Available Over the last few decades, wine makers have been producing wines with a higher alcohol content, assuming that they are more appreciated by consumers. To test this hypothesis, we used functional magnetic imaging to compare reactions of human subjects to different types of wine, focusing on brain regions critical for flavor processing and food reward. Participants were presented with carefully matched pairs of high- and low-alcohol content red wines, without informing them of any of the wine attributes. Contrary to expectation, significantly greater activation was found for low-alcohol than for high-alcohol content wines in brain regions that are sensitive to taste intensity, including the insula as well as the cerebellum. Wines were closely matched for all physical attributes except for alcohol content, thus we interpret the preferential response to the low-alcohol content wines as arising from top-down modulation due to the low alcohol content wines inducing greater attentional exploration of aromas and flavours. The findings raise intriguing possibilities for objectively testing hypotheses regarding methods of producing a highly complex product such as wine.

  15. Temperature Changes in the Brain of Patients Undergoing MRI Examination

    Directory of Open Access Journals (Sweden)

    Theresa Bebaaku Dery

    2013-04-01

    Full Text Available Magnetic Resonance Imaging scanners have become important tools in modern day health care. During the imaging process, total radiofrequency power is transferred from the RF coil to the brain tissues resulting in increase in temperature in the subject being imaged. Currently, reliable and validated means to predict RF heating are not unavailable.This research was conducted to determine temperature changes in the human brain during MRI examination.This study was carried out at two MRI Units in Ghana. One hundred and twenty-six patients were investigated. Data collected include pre- and post-scan tympanic temperatures and specific absorption rates values. The average pre- and post-scan tympanic temperatures measured for Centre A were 36.5±0.1 °C and 37.0±0.1 °C respectively with an average change in temperature of 0.5±0.1 °C for 30.68 minutes scan and an average SAR value of 1.25 W/kg. Centre B measured average pre- and post-scan tympanic temperatures of 36.4±0.1 °C and 36.8±0.1 °C respectively with an average change in temperature of 0.4±0.1 °C for 41.58 minutes scan and an average SAR value of 0.1 W/kg.The rise in tympanic temperature and SAR values were within guidance level of 1 °C recommended by theUnited States Food and Administration and the International Electrotechnical Commission.

  16. Collimator design for a multipinhole brain SPECT insert for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Van Audenhaege, Karen; Van Holen, Roel; Vanhove, Christian; Vandenberghe, Stefaan [Department of Electronics and Information Systems, Ghent University-iMinds Medical IT, MEDISIP-IBiTech, De Pintelaan 185 block B/5, Ghent B-9000 (Belgium)

    2015-11-15

    Purpose: Brain single photon emission computed tomography (SPECT) imaging is an important clinical tool, with unique tracers for studying neurological diseases. Nowadays, most commercial SPECT systems are combined with x-ray computed tomography (CT) in so-called SPECT/CT systems to obtain an anatomical background for the functional information. However, while CT images have a high spatial resolution, they have a low soft-tissue contrast, which is an important disadvantage for brain imaging. Magnetic resonance imaging (MRI), on the other hand, has a very high soft-tissue contrast and does not involve extra ionizing radiation. Therefore, the authors designed a brain SPECT insert that can operate inside a clinical MRI. Methods: The authors designed and simulated a compact stationary multipinhole SPECT insert based on digital silicon photomultiplier detector modules, which have shown to be MR-compatible and have an excellent intrinsic resolution (0.5 mm) when combined with a monolithic 2 mm thick LYSO crystal. First, the authors optimized the different parameters of the SPECT system to maximize sensitivity for a given target resolution of 7.2 mm in the center of the field-of-view, given the spatial constraints of the MR system. Second, the authors performed noiseless simulations of two multipinhole configurations to evaluate sampling and reconstructed resolution. Finally, the authors performed Monte Carlo simulations and compared the SPECT insert with a clinical system with ultrahigh-resolution (UHR) fan beam collimators, based on contrast-to-noise ratio and a visual comparison of a Hoffman phantom with a 9 mm cold lesion. Results: The optimization resulted in a stationary multipinhole system with a collimator radius of 150.2 mm and a detector radius of 172.67 mm, which corresponds to four rings of 34 diSPM detector modules. This allows the authors to include eight rings of 24 pinholes, which results in a system volume sensitivity of 395 cps/MBq. Noiseless simulations

  17. Comparison of CT and MRI brain tumor imaging using a canine glioma model.

    Science.gov (United States)

    Whelan, H T; Clanton, J A; Wilson, R E; Tulipan, N B

    1988-01-01

    A canine gliosarcoma model was used to study the effectiveness of magnetic resonance imaging (MRI) with gadolinium contrast enhancement in defining the histologic margins of brain tumors. The effectiveness of this technique was compared to conventional computed tomography (CT) using iodinated contrast enhancement. Cultured canine gliosarcoma cells were injected into the left hemisphere of adult mongrel dogs. The dogs developed brain tumors and progressive clinical signs. Serial MRI with and without gadolinium diethylene triamine penta-acetic acid was compared to serial CT with and without sodium iothalamate obtained on the same days. After the final scans, animals were sacrificed; the brains were removed and processed for routine histopathologic study. All tumors were visualized with contrast-enhanced MRI which proved most sensitive. Gadolinium di-ethylene triamine penta-acetic acid caused bright enhancement of tumors in a distribution that consistently corresponded to areas of pathologically proved tumor infiltration. Gross and microscopic autopsy findings correlated better with MRI than with CT which tended to produce poorer resolution and underrepresent the size of viable tumor. Gadolinium-enhanced MRI is more accurate than unenhanced MRI, unenhanced CT, or enhanced CT in defining the histologic margins of tumors.

  18. Effects of incentives, age, and behavior on brain activation during inhibitory control: a longitudinal fMRI study.

    Science.gov (United States)

    Paulsen, David J; Hallquist, Michael N; Geier, Charles F; Luna, Beatriz

    2015-02-01

    We investigated changes in brain function supporting inhibitory control under age-controlled incentivized conditions, separating age- and performance-related activation in an accelerated longitudinal design including 10- to 22-year-olds. Better inhibitory control correlated with striatal activation during neutral trials, while Age X Behavior interactions in the striatum indicated that in the absence of extrinsic incentives, younger subjects with greater reward circuitry activation successfully engage in greater inhibitory control. Age was negatively correlated with ventral amygdala activation during Loss trials, suggesting that amygdala function more strongly mediates bottom-up processing earlier in development when controlling the negative aspects of incentives to support inhibitory control. Together, these results indicate that with development, reward-modulated cognitive control may be supported by incentive processing transitions in the amygdala, and from facilitative to obstructive striatal function during inhibitory control.

  19. Brain activation by short-term nicotine exposure in anesthetized wild-type and beta2-nicotinic receptors knockout mice: a BOLD fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, S.V.; Changeux, J.P.; Granon, S. [Unite de Neurobiologie Integrative du Systeme Cholinergique, URA CNRS 2182, Institut Pasteur, Departement de Neuroscience, 25 rue du Dr Roux, 75015 Paris (France); Amadon, A.; Giacomini, E.; Le Bihan, D. [Service Hospitalier Frederic Joliot, 4 place du general Leclerc, 91400 Orsay (France); Wiklund, A. [Section of Anaesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm (Sweden)

    2009-07-01

    Rationale: The behavioral effects of nicotine and the role of the beta2-containing nicotinic receptors in these behaviors are well documented. However, the behaviors altered by nicotine rely on the functioning on multiple brain circuits where the high-affinity {beta}2-containing nicotinic receptors ({beta}2*nAChRs) are located. Objectives We intend to see which brain circuits are activated when nicotine is given in animals naive for nicotine and whether the {beta}2*nAChRs are needed for its activation of the blood oxygen level dependent (BOLD) signal in all brain areas. Materials and methods: We used functional magnetic resonance imaging (fMRI) to measure the brain activation evoked by nicotine (1 mg/kg delivered at a slow rate for 45 min) in anesthetized C57BL/6J mice and {beta}2 knockout (KO) mice. Results: Acute nicotine injection results in a significant increased activation in anterior frontal, motor, and somatosensory cortices and in the ventral tegmental area and the substantia nigra. Anesthetized mice receiving no nicotine injection exhibited a major decreased activation in all cortical and subcortical structures, likely due to prolonged anesthesia. At a global level, {beta}2 KO mice were not rescued from the globally declining BOLD signal. However, nicotine still activated regions of a meso-cortico-limbic circuit likely via {alpha}7 nicotinic receptors. Conclusions: Acute nicotine exposure compensates for the drop in brain activation due to anesthesia through the meso-cortico-limbic network via the action of nicotine on {beta}2*nAChRs. The developed fMRI method is suitable for comparing responses in wild-type and mutant mice. (authors)

  20. Unraveling the multiscale structural organization and connectivity of the human brain: the role of diffusion MRI

    Directory of Open Access Journals (Sweden)

    Matteo eBastiani

    2015-06-01

    Full Text Available The structural architecture and the anatomical connectivity of the human brain show different organizational principles at distinct spatial scales. Histological staining and light microscopy techniques have been widely used in classical neuroanatomical studies to unravel brain organization. Using such techniques is a laborious task performed on 2-dimensional histological sections by skilled anatomists possibly aided by semi-automated algorithms. With the recent advent of modern magnetic resonance imaging (MRI contrast mechanisms, cortical layers and columns can now be reliably identified and their structural properties quantified post mortem. These developments are allowing the investigation of neuroanatomical features of the brain at a spatial resolution that could be interfaced with that of histology. Diffusion MRI and tractography techniques, in particular, have been used to probe the architecture of both white and gray matter in three dimensions. Combined with mathematical network analysis, these techniques are increasingly influential in the investigation of the macro-, meso- and microscopic organization of brain connectivity and anatomy, both in vivo and ex vivo. Diffusion MRI-based techniques in combination with histology approaches can therefore support the endeavor of creating multimodal atlases that take into account the different spatial scales or levels on which the brain is organized. The aim of this review is to illustrate and discuss the structural architecture and the anatomical connectivity of the human brain at different spatial scales and how recently developed diffusion MRI techniques can help investigate these.

  1. Brain Metastases from Different Primary Carcinomas: an Evaluation of DSC MRI Measurements.

    Science.gov (United States)

    Zhang, H; Zhang, G; Oudkerk, M

    2012-03-01

    This study evaluated the roles of different dynamic susceptibility contrast magnetic imaging (DSC MRI) measurements in discriminating between brain metastases derived from four common primary carcinomas. Thirty-seven patients with brain metastases were enrolled. Relative cerebral blood volume (rCBV), cerebral blood flow (rCBF) and relative mean transit time (rMTT) in both tumor and peritumoral edema were measured. Metastases were grouped by their primary tumor (lung, gastrointestinal, breast and renal cell carcinoma). DSC MRI measurements were compared between groups. Mean rCBV, rCBF, rMTT in tumor and peritumoral edema of all brain metastases (n=37) were 2.79 ± 1.73, 2.56 ± 2.11, 1.21 ± 0.48 and 1.05 ± 0.53, 0.86 ± 0.40, 1.99 ± 0.41, respectively. The tumoral rCBV (5.26 ± 1.89) and rCBF (5.32 ± 3.28) of renal metastases were greater than those of the other three metastases (P0.05). Evaluating various DSC MRI measurements can provide complementary hemodynamic information on brain metastases. The tumoral rCBV, rCBF and likely rMTT can help discriminate between brain metastases originating from different primary carcinomas. The peritumoral DSC MRI measurements had limited value in discriminating between brain metastases.

  2. Safety of a dedicated brain MRI protocol in patients with a vagus nerve stimulator.

    Science.gov (United States)

    de Jonge, Jeroen C; Melis, Gerrit I; Gebbink, Tineke A; de Kort, Gérard A P; Leijten, Frans S S

    2014-11-01

    Although implanted metallic devices constitute a relative contraindication to magnetic resonance imaging (MRI) scanning, the safety of brain imaging in a patient with a vagus nerve stimulator (VNS) is classified as "conditional," provided that specific manufacturer guidelines are followed when a transmit and receive head coil is used at 1.5 or 3.0 Tesla. The aim of this study was to evaluate the safety of performing brain MRI scans in patients with the VNS. From September 2009 until November 2011, 101 scans were requested in 73 patients with the VNS in The Netherlands. Patients were scanned according to the manufacturer's guidelines. No patient reported any side effect, discomfort, or pain during or after the MRI scan. In one patient, a lead break was detected based on device diagnostics after the MRI-scan. However, because no system diagnostics had been performed prior to MR scanning in this patient, it is unclear whether MR scanning was responsible for the lead break. The indication for most scans was epilepsy related. Twenty-six scans (26%) were part of a (new) presurgical evaluation and could probably better have been performed prior to VNS implantation. Performing brain MRI scans in patients with an implanted VNS is safe when a modified MRI protocol is followed.

  3. Quantifying brain microstructure with diffusion MRI

    DEFF Research Database (Denmark)

    Novikov, Dmitry S.; Jespersen, Sune N.; Kiselev, Valerij G.

    2016-01-01

    We review, systematize and discuss models of diffusion in neuronal tissue, by putting them into an overarching physical context of coarse-graining over an increasing diffusion length scale. From this perspective, we view research on quantifying brain microstructure as occurring along the three ma...

  4. Pseudo-progression after stereotactic radiotherapy of brain metastases: lesion analysis using MRI cine-loops.

    Science.gov (United States)

    Wiggenraad, Ruud; Bos, Petra; Verbeek-de Kanter, Antoinette; Lycklama À Nijeholt, Geert; van Santvoort, Jan; Taphoorn, Martin; Struikmans, Henk

    2014-09-01

    Stereotactic radiotherapy (SRT) of brain metastasis can lead to lesion growth caused by radiation toxicity. The pathophysiology of this so-called pseudo-progression is poorly understood. The purpose of this study was to evaluate the use of MRI cine-loops for describing the consecutive events in this radiation induced lesion growth. Ten patients were selected from our department's database that had received SRT of brain metastases and had lesion growth caused by pseudo-progression as well as at least five follow-up MRI scans. Pre- and post SRT MRI scans were co-registered and cine-loops were made using post-gadolinium 3D T1 axial slices. The ten cine loops were discussed in a joint meeting of the authors. The use of cine-loops was superior to evaluation of separate MRI scans for interpretation of events after SRT. There was a typical lesion evolution pattern in all patients with varying time course. Initially regression of the metastases was observed, followed by an enlarging area of new contrast enhancement in the surrounding brain tissue. Analysis of consecutive MRI's using cine-loops may improve understanding of pseudo-progression. It probably represents a radiation effect in brain tissue surrounding the irradiated metastasis and not enlargement of the metastasis itself.

  5. Evaluation of Brain and Cervical MRI Abnormality Rates in Patients With Systemic Lupus Erythematosus With or Without Neurological Manifestations

    Directory of Open Access Journals (Sweden)

    Seyed Reza Najafizadeh

    2011-11-01

    Full Text Available Background: Central nervous system (CNS involvement has been observed in 14-80% of patients with systemic lupus erythematosus (SLE. Magnetic resonance imaging (MRI is an appropriate method for evaluating CNS involvement in these patients. Clinical manifestations and MRI findings of CNS lupus should be differentiated from other mimicking diseases such as multiple sclerosis (MS.Objectives: The aim of this study was to evaluate the prevalence and extent of brain and cervical cord MRI lesions of lupus patients. The relationship between neurological signs and symptoms and MRI findings were evaluated as well.Patients and Methods: Fifty SLE patients who had been referred to the rheumatology clinic of our hospital within 2009 were included in a cross sectional study. All patients fulfilled the revised 1981 American College of Rheumatology (ACR criteria for SLE. We evaluated the neurological signs and symptoms and brain and cervical MRI findings in these patients.Results: Forty-one patients (82% were female and nine (18% were male. The mean age was 30.1 ± 9.3 years. Twenty eight (56% patients had an abnormal brain MRI. No one showed any abnormality in the cervical MRI. The lesions in 20 patients were similar to demyelinative plaques. Seventeen patients with abnormal brain MRI were neurologically asymptomatic. There was only a significant relationship between neurological motor manifestations and brain MRI abnormal findings.Conclusions: Unlike the brain, cervical MRI abnormality and especially asymptomatic cord involvement in MRI is quite rare in SLE patients. This finding may be helpful to differentiate SLE from other CNS disorders such as MS.

  6. Brain MRI in patients with multiple sclerosis with oligoclonal cerebrospinal fluid bands

    Directory of Open Access Journals (Sweden)

    Mesaroš Šarlota

    2003-01-01

    Full Text Available Locally produced oligoclonal IgG bands (OCB are present in the cerebrospinal fluid (CSF of 95% patients with multiple sclerosis (MS[2,3]. The most sensitive method for the detection of OCB is isoelectric focusing (IEF [1]. Occasional patients with clinically definite MS lack evidence for intrathecal IgG synthesis [2,9]. This study was designed to compare brain magnetic resonance imagining (MRI findings between CSF OCB positive and negative MS patients. The study comprised 22 OB negative patients with clinically definite MS and 22 OCB positive controls matched for age, disease duration, activity and course of MS. In the both groups clinical assessment was performed by using Expanded Disability Status Scale (EDSS score. T2 weighted MRI of the brain was performed on a Siemens Magnetom (1.0 T. Lesions were countred and sized for 15 anatomically defined locations:7 periventricular (PV and 8 non-periventricular (NPV regions. An arbitrary scoring system weighted for lesions size was used to estimate total and regional lesions loads: a1 point was given for each lesion with a diameter 1-5 mm, b 2 points for one lesion with a diameter 6-10 mm, c 3 points for one over 10 mm, and confluent lesions scored one extra point [16]. Atrophy were scored as follows: 0-normal size, 1-mild atrophy, 2-moderate atrophy and 3-severe atrophy. Mean score of total brain MRI loads was lower in OCB negative than in OCB positive MS patients (44 vs. 50 but the difference was not statistically significant. Mean periventricular (32 vs. 23 non-periventricular (26 vs. 19 and infratentorial (11 vs. 9 scores were higher in OCB positive MS group in comparison with OCB negative patients but non-significant (figure 1. There was no correlation between EDSS score and total MRI lesions load in OCB negative MS patients, while in OCB positive group we detected significant correlation between EDSS score and total MRI lesions load (p=0.026 (figure 2. The results of this study demonstrate that

  7. Microtesla MRI of the human brain with simultaneous MEG

    CERN Document Server

    Zotev, V S; Matlashov, A N; Savukov, I M; Espy, M A; Mosher, J C; Gómez, J J; Kraus, R H

    2007-01-01

    Magnetic resonance imaging at ultra-low fields (ULF MRI) uses SQUIDs (superconducting quantum interference devices) to measure spin precession at a microtesla-range field after sample magnetization is enhanced by a stronger pre-polarizing field. Here, the first ULF images of the human head acquired at 46 microtesla measurement field with pre-polarization at 30 mT are reported. The imaging was performed with 3 mm x 3 mm x 6 mm resolution using the seven-channel SQUID system designed for both ULF MRI and magnetoencephalography (MEG). Auditory MEG signals were measured immediately after the imaging while the human subject remained inside the system. These results demonstrate that ULF MRI of the human brain is feasible and can be naturally combined with MEG.

  8. How skill expertise shapes the brain functional architecture: an fMRI study of visuo-spatial and motor processing in professional racing-car and naïve drivers.

    Science.gov (United States)

    Bernardi, Giulio; Ricciardi, Emiliano; Sani, Lorenzo; Gaglianese, Anna; Papasogli, Alessandra; Ceccarelli, Riccardo; Franzoni, Ferdinando; Galetta, Fabio; Santoro, Gino; Goebel, Rainer; Pietrini, Pietro

    2013-01-01

    The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI), we measured brain activity while eleven Formula racing-car drivers and eleven 'naïve' volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD) signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both 'quantitative' and 'qualitative' modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased 'neural efficiency' in the brain of highly skilled individuals.

  9. Impact of CT/MRI Image Registration on Target Delineation of Radiotherapy for Lung Cancer with Brain Metastasis

    Directory of Open Access Journals (Sweden)

    Yang LI

    2012-08-01

    Full Text Available Background and objective Accurate target delineation in radiation therapy is a key component of the treatment regimen for brain metastasis for which CT/MRI fusion technology provides a feasible method. The aim of this study is to explore the role of CT/MRI image registration in target delineation for lung cancer with brain metastasis. Methods The image data of 31 patients were processed using Oncentra MasterPlan. The GTVs were delineated on CT and CT/MRI images, and their differences were compared to analyze the impact of the maximum average error and tumor edema on target delineation. Results The GTVs delineated on CT/MRI images were markedly smaller than those delineated on CT images. Target delineation was clearly influenced by edema. Conclusion The technology of CT/MRI image registration can improve the accuracy of target delineation for lung cancer with brain metastasis.

  10. Morphometric connectivity analysis to distinguish normal, mild cognitive impaired, and Alzheimer subjects based on brain MRI

    DEFF Research Database (Denmark)

    Erleben, Lene Lillemark; Sørensen, Lauge; Mysling, Peter

    2013-01-01

    This work investigates a novel way of looking at the regions in the brain and their relationship as possible markers to classify normal control (NC), mild cognitive impaired (MCI), and Alzheimer Disease (AD) subjects. MRI scans from a subset of 101 subjects from the ADNI study at baseline was used...

  11. Serial cranial ultrasonography or early MRI for detecting preterm brain injury?

    NARCIS (Netherlands)

    Plaisier, Annemarie; Raets, Marlou M A; Ecury-Goossen, Ginette M; Govaert, Paul; Feijen-Roon, Monique; Reiss, Irwin K M; Smit, Liesbeth S; Lequin, Maarten H; Dudink, Jeroen

    2015-01-01

    OBJECTIVE: To investigate detection ability and feasibility of serial cranial ultrasonography (CUS) and early MRI in preterm brain injury. DESIGN: Prospective cohort study. SETTING: Level III neonatal intensive care unit. PATIENTS: 307 infants, born below 29 weeks of gestation. METHODS: Serial CUS a

  12. Brain infarcts due to scorpion stings in children: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Bouzas, A.; Ballesteros-Maresma, A. [Univ. Nacional Autonoma de Mexico, Mexico (Mexico); Morales-Resendiz, M.L. [Hospital General de Queretaro, Mexico (Mexico); Llamas-Ibarra, F. [Clinica Neurologica de Queretaro, Mexico (Mexico); Martinez-Lopez, M. [Fundacion Clinica Medica Sur., Mexico (Mexico)

    2000-02-01

    We report two children with severe neurological complications after having been stung by a scorpion. Clinical and MRI findings suggested brain infarcts. The lesions seen were in pons in one child and the right hemisphere in the other. The latter also showed possible hyperemia in the infarcted area. No vascular occlusions were observed and we therefore think the brain infarcts were a consequence of the scorpion sting. The cause of the infarct may be hypotension, shock or depressed left ventricular function, all of which are frequent in severe poisoning by scorpion sting. (orig.)

  13. Imaging Findings of Brain Death on 3-Tesla MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chul Ho [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Hwa Pyung [Dept. of Occupational and Environmental Medicine, CHA Gumi Medical Center, CHA University, Gumi (Korea, Republic of); Park, Jun Beom [Dept. of Radiology, Korean Armed Force Daejeon Hospital, Daejeon (Korea, Republic of); Chang, Hyuk Won; Kim, Easlmaan; Park, Ui Jun; Kim, Hyoung Tae [Keimyung University College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Kim, Eun Hee [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Ku, Jeong Hun [Dept. of Biomedical Engineering, Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2012-09-15

    To demonstrate the usefulness of 3-tesla (3T) magnetic resonance imaging (MRI) including T2-weighted imaging (T2WI), diffusion weighted imaging (DWI), time-of-flight (TOF) magnetic resonance angiography (MRA), T2*-weighted gradient recalled echo (GRE), and susceptibility weighted imaging (SWI) in diagnosing brain death. Magnetic resonance imaging findings for 10 patients with clinically verified brain death (group I) and seven patients with comatose or stuporous mentality who did not meet the clinical criteria of brain death (group II) were retrospectively reviewed. Tonsilar herniation and loss of intraarterial flow signal voids (LIFSV) on T2WI were highly sensitive and specific findings for the diagnosis of brain death (p < 0.001 and < 0.001, respectively). DWI, TOF-MRA, and GRE findings were statistically different between the two groups (p = 0.015, 0.029, and 0.003, respectively). However, cortical high signal intensities in T2WI and SWI findings were not statistically different between the two group (p = 0.412 and 1.0, respectively). T2-weighted imaging, DWI, and MRA using 3T MRI may be useful for diagnosing brain death. However, SWI findings are not specific due to high false positive findings.

  14. Optimal Gaussian Mixture Models of Tissue Intensities in Brain MRI of Patients with Multiple-Sclerosis

    Science.gov (United States)

    Xiao, Yiming; Shah, Mohak; Francis, Simon; Arnold, Douglas L.; Arbel, Tal; Collins, D. Louis

    Brain tissue segmentation is important in studying markers in human brain Magnetic Resonance Images (MRI) of patients with diseases such as Multiple Sclerosis (MS). Parametric segmentation approaches typically assume unimodal Gaussian distributions on MRI intensities of individual tissue classes, even in applications on multi-spectral images. However, this assumption has not been rigorously verified especially in the context of MS. In this work, we evaluate the local MRI intensities of both healthy and diseased brain tissues of 21 multi-spectral MRIs (63 volumes in total) of MS patients for adherence to this assumption. We show that the tissue intensities are not uniform across the brain and vary across (anatomical) regions of the brain. Consequently, we show that Gaussian mixtures can better model the multi-spectral intensities. We utilize an Expectation Maximization (EM) based approach to learn the models along with a symmetric Jeffreys divergence criterion to study differences in intensity distributions. The effects of these findings are also empirically verified on automatic segmentation of brains with MS.

  15. Segmentation of Brain Tumors in MRI Images Using Three-Dimensional Active Contour without Edge

    Directory of Open Access Journals (Sweden)

    Ali M. Hasan

    2016-11-01

    Full Text Available Brain tumor segmentation in magnetic resonance imaging (MRI is considered a complex procedure because of the variability of tumor shapes and the complexity of determining the tumor location, size, and texture. Manual tumor segmentation is a time-consuming task highly prone to human error. Hence, this study proposes an automated method that can identify tumor slices and segment the tumor across all image slices in volumetric MRI brain scans. First, a set of algorithms in the pre-processing stage is used to clean and standardize the collected data. A modified gray-level co-occurrence matrix and Analysis of Variance (ANOVA are employed for feature extraction and feature selection, respectively. A multi-layer perceptron neural network is adopted as a classifier, and a bounding 3D-box-based genetic algorithm is used to identify the location of pathological tissues in the MRI slices. Finally, the 3D active contour without edge is applied to segment the brain tumors in volumetric MRI scans. The experimental dataset consists of 165 patient images collected from the MRI Unit of Al-Kadhimiya Teaching Hospital in Iraq. Results of the tumor segmentation achieved an accuracy of 89% ± 4.7% compared with manual processes.

  16. Diffusion MRI of the neonate brain: acquisition, processing and analysis techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pannek, Kerstin [University of Queensland, Centre for Clinical Research, Brisbane (Australia); University of Queensland, School of Medicine, Brisbane (Australia); University of Queensland, Centre for Advanced Imaging, Brisbane (Australia); Guzzetta, Andrea [IRCCS Stella Maris, Department of Developmental Neuroscience, Calambrone Pisa (Italy); Colditz, Paul B. [University of Queensland, Centre for Clinical Research, Brisbane (Australia); University of Queensland, Perinatal Research Centre, Brisbane (Australia); Rose, Stephen E. [University of Queensland, Centre for Clinical Research, Brisbane (Australia); University of Queensland, Centre for Advanced Imaging, Brisbane (Australia); University of Queensland Centre for Clinical Research, Royal Brisbane and Women' s Hospital, Brisbane (Australia)

    2012-10-15

    Diffusion MRI (dMRI) is a popular noninvasive imaging modality for the investigation of the neonate brain. It enables the assessment of white matter integrity, and is particularly suited for studying white matter maturation in the preterm and term neonate brain. Diffusion tractography allows the delineation of white matter pathways and assessment of connectivity in vivo. In this review, we address the challenges of performing and analysing neonate dMRI. Of particular importance in dMRI analysis is adequate data preprocessing to reduce image distortions inherent to the acquisition technique, as well as artefacts caused by head movement. We present a summary of techniques that should be used in the preprocessing of neonate dMRI data, and demonstrate the effect of these important correction steps. Furthermore, we give an overview of available analysis techniques, ranging from voxel-based analysis of anisotropy metrics including tract-based spatial statistics (TBSS) to recently developed methods of statistical analysis addressing issues of resolving complex white matter architecture. We highlight the importance of resolving crossing fibres for tractography and outline several tractography-based techniques, including connectivity-based segmentation, the connectome and tractography mapping. These techniques provide powerful tools for the investigation of brain development and maturation. (orig.)

  17. Patch-based generation of a pseudo CT from conventional MRI sequences for MRI-only radiotherapy of the brain

    DEFF Research Database (Denmark)

    Andreasen, Daniel; Van Leemput, Koen; Hansen, Rasmus H.

    2015-01-01

    Purpose: In radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, the information on electron density must be derived from the MRI scan by creating a so-called pseudo computed tomography (pCT). This is a nontrivial task, since the voxel-intensities in an MRI scan are n...... on conventional T1-weighted MRI sequences and without deformable registrations. In our evaluations, the method performed better than existing voxel-based and atlas-based methods and showed a promising potential for RT of the brain based only on MRI....

  18. To see bruxism: a functional MRI study

    Science.gov (United States)

    2015-01-01

    Objective: Since the pathophysiology of bruxism is not clearly understood, there exists no possible treatment. The aim of this study is to investigate the cerebral activation differences between healthy subjects and patients with bruxism on behalf of possible aetiological factors. Methods: 12 healthy subjects and 12 patients with bruxism, a total of 24 right-handed female subjects (aged 20–27 years) were examined using functional MRI during tooth-clenching and resting tasks. Imaging was performed with 3.0-T MRI scanner with a 32-channel head coil. Differences in regional brain activity between patients with bruxism and healthy subjects (control group) were observed with BrainVoyager QX 2.8 (Brain Innovation, Maastricht, Netherlands) statistical data analysis program. Activation maps were created using the general linear model: single study and multistudy multisubject for statistical group analysis. This protocol was approved by the ethics committee of medical faculty of Kirikkale University, Turkey (02/04), based on the guidelines set forth in the Declaration of Helsinki. Results: The group analysis revealed a statistically significant increase in blood oxygenation level-dependent signal of three clusters in the control group (p < 0.005), which may indicate brain regions related with somatognosis, repetitive passive motion, proprioception and tactile perception. These areas coincide with Brodmann areas 7, 31, 39 and 40. It is conceivable that there are differences between healthy subjects and patients with bruxism. Conclusions: Our findings indicate that there was a decrease of cortical activation pattern in patients with bruxism in clenching tasks. This indicates decreased blood flow and activation in regional neuronal activity. Bruxism, as an oral motor disorder concerns dentistry, neurology and psychiatry. These results might improve the understanding and physiological handling of sleep bruxism. PMID:25806864

  19. volBrain: an online MRI brain volumetry system

    Directory of Open Access Journals (Sweden)

    Jose V. Manjon

    2016-07-01

    Full Text Available The amount of medical image data produced in clinical and research settings is rapidly growing resulting in vast amount of data to analyze. Automatic and reliable quantitative analysis tools, including segmentation, allow to analyze brain development and to understand specific patterns of many neurological diseases. This field has recently experienced many advances with successful techniques based on non-linear warping and label fusion. In this work we present a novel and fully automatic pipeline for volumetric brain analysis based on multi-atlas label fusion technology that is able to provide accurate volumetric information at different levels of detail in a short time. This method is available through the volBrain online web interface (http://volbrain.upv.es, which is publically and freely accessible to the scientific community. Our new framework has been compared with current state-of-the-art methods showing very competitive results.

  20. Resting-state fMRI studies in epilepsy

    Institute of Scientific and Technical Information of China (English)

    Wurina; Yu-Feng Zang; Shi-Gang Zhao

    2012-01-01

    Epilepsy is a disease characterized by abnormal spontaneous activity in the brain.Resting-state functional magnetic resonance imaging (RS-fMRI) is a powerful technique for exploring this activity.With good spatial and temporal resolution,RS-fMRI is a promising approach for accurate localization of the focus of seizure activity.Although simultaneous electroencephalogram-fMR1 has been performed with patients in the resting state,most studies focused on activation.This mini-review focuses on RS-fMRI alone,including its computational methods and its application to epilepsy.

  1. A stereotaxic MRI template set for the rat brain with tissue class distribution maps and co-registered anatomical atlas: application to pharmacological MRI.

    Science.gov (United States)

    Schwarz, Adam J; Danckaert, Anne; Reese, Torsten; Gozzi, Alessandro; Paxinos, George; Watson, Charles; Merlo-Pich, Emilio V; Bifone, Angelo

    2006-08-15

    We describe a stereotaxic rat brain MRI template set with a co-registered digital anatomical atlas and illustrate its application to the analysis of a pharmacological MRI (phMRI) study of apomorphine. The template set includes anatomical images and tissue class probability maps for brain parenchyma and cerebrospinal fluid (CSF). These facilitate the use of standard fMRI software for spatial normalisation and tissue segmentation of rat brain data. A volumetric reconstruction of the Paxinos and Watson rat brain atlas is also co-localised with the template, enabling the atlas structure and stereotaxic coordinates corresponding to a feature within a statistical map to be interactively reported, facilitating the localisation of functional effects. Moreover, voxels falling within selected brain structures can be combined to define anatomically based 3D volumes of interest (VOIs), free of operator bias. As many atlas structures are small relative to the typical resolution of phMRI studies, a mechanism for defining composite structures as agglomerations of individual atlas structures is also described. This provides a simple and robust means of interrogating structures that are otherwise difficult to delineate and an objective framework for comparing and classifying compounds based on an anatomical profile of their activity. These developments allow a closer alignment of pre-clinical and clinical analysis techniques.

  2. Assessment of blood–brain barrier disruption using dynamic contrast-enhanced MRI. A systematic review

    Directory of Open Access Journals (Sweden)

    Anna K. Heye

    2014-01-01

    Full Text Available There is increasing recognition of the importance of blood–brain barrier (BBB disruption in aging, dementia, stroke and multiple sclerosis in addition to more commonly-studied pathologies such as tumors. Dynamic contrast-enhanced MRI (DCE-MRI is a method for studying BBB disruption in vivo. We review pathologies studied, scanning protocols and data analysis procedures to determine the range of available methods and their suitability to different pathologies. We systematically review the existing literature up to February 2014, seeking studies that assessed BBB integrity using T1-weighted DCE-MRI techniques in animals and humans in normal or abnormal brain tissues. The literature search provided 70 studies that were eligible for inclusion, involving 417 animals and 1564 human subjects in total. The pathologies most studied are intracranial neoplasms and acute ischemic strokes. There are large variations in the type of DCE-MRI sequence, the imaging protocols and the contrast agents used. Moreover, studies use a variety of different methods for data analysis, mainly based on model-free measurements and on the Patlak and Tofts models. Consequently, estimated KTrans values varied widely. In conclusion, DCE-MRI is shown to provide valuable information in a large variety of applications, ranging from common applications, such as grading of primary brain tumors, to more recent applications, such as assessment of subtle BBB dysfunction in Alzheimer's disease. Further research is required in order to establish consensus-based recommendations for data acquisition and analysis and, hence, improve inter-study comparability and promote wider use of DCE-MRI.

  3. Assessment of blood–brain barrier disruption using dynamic contrast-enhanced MRI. A systematic review

    Science.gov (United States)

    Heye, Anna K.; Culling, Ross D.; Valdés Hernández, Maria del C.; Thrippleton, Michael J.; Wardlaw, Joanna M.

    2014-01-01

    There is increasing recognition of the importance of blood–brain barrier (BBB) disruption in aging, dementia, stroke and multiple sclerosis in addition to more commonly-studied pathologies such as tumors. Dynamic contrast-enhanced MRI (DCE-MRI) is a method for studying BBB disruption in vivo. We review pathologies studied, scanning protocols and data analysis procedures to determine the range of available methods and their suitability to different pathologies. We systematically review the existing literature up to February 2014, seeking studies that assessed BBB integrity using T1-weighted DCE-MRI techniques in animals and humans in normal or abnormal brain tissues. The literature search provided 70 studies that were eligible for inclusion, involving 417 animals and 1564 human subjects in total. The pathologies most studied are intracranial neoplasms and acute ischemic strokes. There are large variations in the type of DCE-MRI sequence, the imaging protocols and the contrast agents used. Moreover, studies use a variety of different methods for data analysis, mainly based on model-free measurements and on the Patlak and Tofts models. Consequently, estimated KTrans values varied widely. In conclusion, DCE-MRI is shown to provide valuable information in a large variety of applications, ranging from common applications, such as grading of primary brain tumors, to more recent applications, such as assessment of subtle BBB dysfunction in Alzheimer's disease. Further research is required in order to establish consensus-based recommendations for data acquisition and analysis and, hence, improve inter-study comparability and promote wider use of DCE-MRI. PMID:25379439

  4. Brain MRI and single photon emission computed tomography in severe athetotic cerebral palsy. A comparative study with mental and motor disorders

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Kazutaka; Tsuzura, Shigenobu [Metropolitan Medical Center of the Severely Handicapped, Fuchu, Tokyo (Japan); Matsuda, Hiroshi

    1995-07-01

    Single photon emission computed tomography (SPECT) using N-isopropyl-p-[{sup 123}I]-iodoamphetamine ({sup 123}I-IMP) was performed in twelve patients with severe athetotic cerebral palsy (Ath; 5 males and 7 females) who had both motor delay (unable to move) and mental retardation (I.Q, or D.Q, below 30). The neuroimaging findings of those patients were compared with those of patients mental and motor disorders. In five caes suffering from neonatal asphyxia, SPECT demonstrated a decreased regional cerebral blood flow (rCBF) in corpus striatum, thalamus, orbitofrontal areas, pericentral gyrus areas, prefrontal areas and medial temporal areas. In seven cases suffering from neonatal jaundice, SPECT demonstrated a decreased rCBF in orbito-frontal areas, prefrontal areas and medial temporal areas. SPECT showed hypoperfusion of peri-central gyrus areas in cases with complications of spastic palsy. The decreased rCBF in medial temporal areas mostly corresponded to an alteration in hippocampal formation as assessed by magnetic resonance imaging (MRI). Cases with hypoperfusion of bilateral medial temporal areas showed a lower score of language understanding than those with the unilateral damage. In cases with hypofusion of bilateral prefrontal areas and bilateral medial temporal areas, the grade of understanding of language was almost below 12 months. In cases with hypoperfusion of orbitofrontal areas, psychomotor hypersensitivity had been observed. Those results suggest that IMP-SPECT and MRI of the brain is useful tool for neurological assessment in handicapped patients with athetotic cerebral palsy. (author).

  5. Paediatric brain-stem gliomas: MRI, FDG-PET and histological grading correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jong Won; Kim, In-One; Cheon, Jung-Eun; Kim, Woo Sun; Moon, Sung Gyu; Kim, Tae Jung; Yeon, Kyung Mo [Seoul National University Hospital, Department of Radiology, Seoul (Korea); Chi, Je Geun [Seoul National University College of Medicine, Department of Pathology, Seoul (Korea); Wang, Kyu-Chang [Seoul National University College of Medicine, Department of Neurosurgery, Seoul (Korea); Chung, June Key [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea)

    2006-09-15

    MRI and FDG-PET may predict the histological grading of paediatric brain-stem gliomas. To assess MRI findings and metabolic imaging using FDG-PET of brain-stem gliomas based on histological grading. Included in the study were 20 paediatric patients (age 3-14 years, mean 8.2 years) with brain-stem glioma (five glioblastomas, ten anaplastic astrocytomas and five low-grade astrocytomas). MR images were assessed for the anatomical site of tumour origin, focality, pattern of tumour growth, and enhancement. All glioblastomas were located in the pons and showed diffuse pontine enlargement with focally exophytic features. Eight anaplastic astrocytomas were located in the pons and demonstrated diffuse pontine enlargement without exophytic features. Low-grade astrocytomas were located in the pons, midbrain or medulla and showed focally exophytic growth features and peripheral enhancement. In 12 patients in whom FDG-PET was undertaken, glioblastomas showed hypermetabolic or hypometabolic lesions, anaplastic astrocytomas showed no metabolic change or hypometabolic lesions and low-grade astrocytomas showed hypometabolism compared with the cerebellum. MRI findings correlated well with histological grading of brain-stem gliomas and MRI may therefore predict the histological grading. FDG-PET may be helpful in differentiating between anaplastic astrocytoma and glioblastomas among high-grade tumours. (orig.)

  6. The usefulness of brain MRI and CT in the clinical practice of epilepsia

    Energy Technology Data Exchange (ETDEWEB)

    Horita, Hideki [Jikei Univ., Komae, Tokyo (Japan). Daisan Hospital; Maekawa, Kihei

    1995-09-01

    This study was conducted to clarify the usefulness of brain MRI and CT in the clinical practice of epilepsy. The subjects were 100 epileptic child patients (average age, 13.2{+-}8.2 years) who underwent brain MRI, including 93 patients who also underwent brain CT. Twenty-two abnormal findings were obtained by MRI and 25 by CT. Thirty-nine patients who had complications such as mental retardation, cerebral palsy, or the overlapping disorders showed abnormal findings in a significantly high incidence. No significant correlations existed between the presence or absence of abnormal findings and the disease course after seizures. Patients with symptomatic localization-related epilepsies or cryptogenic and symptomatic generalized epilepsies showed abnormal findings in a significantly high incidence and unfavorable disease course after seizures. In 10 of 28 patients who showed abnormal findings, the abnormal finding site on images were correlated to the focus site on electroencephalograms. In conclusion, brain MRI and CT are essential in the clinical practice of epilepsy, however, we should notice the limitation of these methods. (Y.S.).

  7. Patch-based generation of a pseudo CT from conventional MRI sequences for MRI-only radiotherapy of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Andreasen, Daniel, E-mail: dana@dtu.dk [Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kgs. Lyngby 2800, Denmark and Department of Oncology, Radiotherapy Research Unit, Copenhagen University Hospital, Herlev 2730 (Denmark); Van Leemput, Koen [Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kgs. Lyngby 2800, Denmark and A.A. Martinos Center for Biomedical Imaging, MGH, Harvard Medical School, Charlestown, Massachusetts 02129 (United States); Hansen, Rasmus H. [Department of Radiology, Copenhagen University Hospital, Herlev 2730 (Denmark); Andersen, Jon A. L.; Edmund, Jens M. [Department of Oncology, Radiotherapy Research Unit, Copenhagen University Hospital, Herlev 2730 (Denmark)

    2015-04-15

    Purpose: In radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, the information on electron density must be derived from the MRI scan by creating a so-called pseudo computed tomography (pCT). This is a nontrivial task, since the voxel-intensities in an MRI scan are not uniquely related to electron density. To solve the task, voxel-based or atlas-based models have typically been used. The voxel-based models require a specialized dual ultrashort echo time MRI sequence for bone visualization and the atlas-based models require deformable registrations of conventional MRI scans. In this study, we investigate the potential of a patch-based method for creating a pCT based on conventional T{sub 1}-weighted MRI scans without using deformable registrations. We compare this method against two state-of-the-art methods within the voxel-based and atlas-based categories. Methods: The data consisted of CT and MRI scans of five cranial RT patients. To compare the performance of the different methods, a nested cross validation was done to find optimal model parameters for all the methods. Voxel-wise and geometric evaluations of the pCTs were done. Furthermore, a radiologic evaluation based on water equivalent path lengths was carried out, comparing the upper hemisphere of the head in the pCT and the real CT. Finally, the dosimetric accuracy was tested and compared for a photon treatment plan. Results: The pCTs produced with the patch-based method had the best voxel-wise, geometric, and radiologic agreement with the real CT, closely followed by the atlas-based method. In terms of the dosimetric accuracy, the patch-based method had average deviations of less than 0.5% in measures related to target coverage. Conclusions: We showed that a patch-based method could generate an accurate pCT based on conventional T{sub 1}-weighted MRI sequences and without deformable registrations. In our evaluations, the method performed better than existing voxel-based and

  8. Prenatal brain MRI of fetuses with Zika virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Guillemette-Artur, Prisca [Centre Hospitalier de Polynesie Francaise, Service de Radiologie, Pirae, Tahiti (Country Unknown); Besnard, Marianne [Centre Hospitalier de Polynesie Francaise, Service de Reanimation Neo-natale, Pirae, Tahiti (Country Unknown); Eyrolle-Guignot, Dominique [Centre Hospitalier de Polynesie Francaise, Service d' Obstetrique, Pirae, Tahiti (Country Unknown); Jouannic, Jean-Marie [Universite Pierre et Marie Curie, Service de Medecine Foetale, Hopital d' Enfants Armand-Trousseau, Paris (France); Garel, Catherine [Hopital d' Enfants Armand-Trousseau, Department of Radiology, Paris (France)

    2016-06-15

    An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections. (orig.)

  9. Vascular changes caused by deep brain stimulation using double-dose gadolinium-enhanced brain MRI

    Institute of Scientific and Technical Information of China (English)

    Byeong Sam Choi; Yong Hwan Kim; Sang Ryong Jeon

    2014-01-01

    We retrospectively analyzed the clinical data of 32 patients with medically intractable idiopathic Parkinson’s disease who had undergone staged bilateral deep brain stimulation of the subtha-lamic nuclei from January 2007 to May 2011. The vascularture of the patients who received two deep brain stimulations was detected using double-dose gadolinium-enhanced brain MRI. The dimensions of straight sinus, superior sagittal sinus, ipsilateral internal cerebral vein in the tha-lamic branch and ipsilateral anterior caudate vein were reduced. These ifndings demonstrate that bilateral deep brain stimulation of the subthalamic nuclei affects cerebral venous blood lfow.

  10. MRI confirms loss of blood-brain barrier integrity in a mouse model of disseminated candidiasis.

    Science.gov (United States)

    Navarathna, Dhammika H M L P; Munasinghe, Jeeva; Lizak, Martin J; Nayak, Debasis; McGavern, Dorian B; Roberts, David D

    2013-09-01

    Disseminated candidiasis primarily targets the kidneys and brain in mice and humans. Damage to these critical organs leads to the high mortality associated with such infections, and invasion across the blood-brain barrier can result in fungal meningoencephalitis. Candida albicans can penetrate a brain endothelial cell barrier in vitro through transcellular migration, but this mechanism has not been confirmed in vivo. MRI using the extracellular vascular contrast agent gadolinium diethylenetriaminepentaacetic acid demonstrated that integrity of the blood-brain barrier is lost during C. albicans invasion. Intravital two-photon laser scanning microscopy was used to provide the first real-time demonstration of C. albicans colonizing the living brain, where both yeast and filamentous forms of the pathogen were found. Furthermore, we adapted a previously described method utilizing MRI to monitor inflammatory cell recruitment into infected tissues in mice. Macrophages and other phagocytes were visualized in kidney and brain by the administration of ultrasmall iron oxide particles. In addition to obtaining new insights into the passage of C. albicans across the brain microvasculature, these imaging methods provide useful tools to study further the pathogenesis of C. albicans infections, to define the roles of Candida virulence genes in kidney versus brain infection and to assess new therapeutic measures for drug development.

  11. Structural Image Analysis of the Brain in Neuropsychology Using Magnetic Resonance Imaging (MRI) Techniques.

    Science.gov (United States)

    Bigler, Erin D

    2015-09-01

    Magnetic resonance imaging (MRI) of the brain provides exceptional image quality for visualization and neuroanatomical classification of brain structure. A variety of image analysis techniques provide both qualitative as well as quantitative methods to relate brain structure with neuropsychological outcome and are reviewed herein. Of particular importance are more automated methods that permit analysis of a broad spectrum of anatomical measures including volume, thickness and shape. The challenge for neuropsychology is which metric to use, for which disorder and the timing of when image analysis methods are applied to assess brain structure and pathology. A basic overview is provided as to the anatomical and pathoanatomical relations of different MRI sequences in assessing normal and abnormal findings. Some interpretive guidelines are offered including factors related to similarity and symmetry of typical brain development along with size-normalcy features of brain anatomy related to function. The review concludes with a detailed example of various quantitative techniques applied to analyzing brain structure for neuropsychological outcome studies in traumatic brain injury.

  12. Comparison of the pathology of cerebral white matter with post-mortem magnetic resonance imaging (MRI) in the elderly brain.

    Science.gov (United States)

    Fernando, M S; O'Brien, J T; Perry, R H; English, P; Forster, G; McMeekin, W; Slade, J Y; Golkhar, A; Matthews, F E; Barber, R; Kalaria, R N; Ince, P G

    2004-08-01

    White matter lesions (WML) on magnetic resonance imaging (MRI) brain scans are associated with ageing. They are unrelated to specific disorders, and their impact on cognitive and other brain functions is poorly characterized. Pathological studies often omit systematic survey of WML because of the need to study multiple full coronal tissue blocks, and uncertainty over the significance of lesions identified in periventricular and deep subcortical regions. Post-mortem MRI provides a means of mapping WML but the sensitivity and specificity of the method are unresolved. In this study post-mortem MRI of WML in fixed brain slices was compared with pathology in 33 brains donated to the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS). This study shows that MRI detection of WML was less sensitive than pathology: periventricaular lesions (PVL) sensitivity = 95% (87-99%), specificity = 71% (44-90%); deep subcortical lesions (DSCL) sensitivity = 86% (79-93%), specificity = 80% (72-88%). False negative MRI was associated with milder pathology, but lesions detected by myelin attenuation alone showed both microglial and endothelial activation. Therefore post-mortem MRI of formalin-fixed brain slices is a reliable method to obtain systematic data on the severity and distribution of cerebral white matter disease, and appears to detect those WML most likely to have clinical impact.

  13. Automated selection of brain regions for real-time fMRI brain-computer interfaces

    Science.gov (United States)

    Lührs, Michael; Sorger, Bettina; Goebel, Rainer; Esposito, Fabrizio

    2017-02-01

    Objective. Brain-computer interfaces (BCIs) implemented with real-time functional magnetic resonance imaging (rt-fMRI) use fMRI time-courses from predefined regions of interest (ROIs). To reach best performances, localizer experiments and on-site expert supervision are required for ROI definition. To automate this step, we developed two unsupervised computational techniques based on the general linear model (GLM) and independent component analysis (ICA) of rt-fMRI data, and compared their performances on a communication BCI. Approach. 3 T fMRI data of six volunteers were re-analyzed in simulated real-time. During a localizer run, participants performed three mental tasks following visual cues. During two communication runs, a letter-spelling display guided the subjects to freely encode letters by performing one of the mental tasks with a specific timing. GLM- and ICA-based procedures were used to decode each letter, respectively using compact ROIs and whole-brain distributed spatio-temporal patterns of fMRI activity, automatically defined from subject-specific or group-level maps. Main results. Letter-decoding performances were comparable to supervised methods. In combination with a similarity-based criterion, GLM- and ICA-based approaches successfully decoded more than 80% (average) of the letters. Subject-specific maps yielded optimal performances. Significance. Automated solutions for ROI selection may help accelerating the translation of rt-fMRI BCIs from research to clinical applications.

  14. Changes in Brain Activation Associated with Spontaneous Improvization and Figural Creativity After Design-Thinking-Based Training: A Longitudinal fMRI Study.

    Science.gov (United States)

    Saggar, Manish; Quintin, Eve-Marie; Bott, Nicholas T; Kienitz, Eliza; Chien, Yin-Hsuan; Hong, Daniel W-C; Liu, Ning; Royalty, Adam; Hawthorne, Grace; Reiss, Allan L

    2016-06-15

    Creativity is widely recognized as an essential skill for entrepreneurial success and adaptation to daily-life demands. However, we know little about the neural changes associated with creative capacity enhancement. For the first time, using a prospective, randomized control design, we examined longitudinal changes in brain activity associated with participating in a five-week design-thinking-based Creative Capacity Building Program (CCBP), when compared with Language Capacity Building Program (LCBP). Creativity, an elusive and multifaceted construct, is loosely defined as an ability to produce useful/appropriate and novel outcomes. Here, we focus on one of the facets of creative thinking-spontaneous improvization. Participants were assessed pre- and post-intervention for spontaneous improvization skills using a game-like figural Pictionary-based fMRI task. Whole-brain group-by-time interaction revealed reduced task-related activity in CCBP participants (compared with LCBP participants) after training in the right dorsolateral prefrontal cortex, anterior/paracingulate gyrus, supplementary motor area, and parietal regions. Further, greater cerebellar-cerebral connectivity was observed in CCBP participants at post-intervention when compared with LCBP participants. In sum, our results suggest that improvization-based creative capacity enhancement is associated with reduced engagement of executive functioning regions and increased involvement of spontaneous implicit processing.

  15. Utility of resting fMRI and connectivity in patients with brain tumor

    Directory of Open Access Journals (Sweden)

    Sandhya Manglore

    2013-01-01

    Full Text Available Background: Resting state (task independent Functional Magnetic Resonance Imaging (fMRI has opened a new avenue in cognitive studies and has found practical clinical applications. Materials and Methods: Resting fMRI analysis was performed in six patients with brain tumor in the motor cortex. For comparison, task-related mapping of the motor cortex was done. Connectivity analysis to study the connections and strength of the connections between the primary motor cortex, premotor cortex, and primary somatosensory cortex on the affected side was also performed and compared with the contralateral normal side and the controls. Results: Resting fMRI in patients with brain tumor in the motor cortex mapped the motor cortex in a task-free state and the results were comparable to the motor task paradigm. Decreased connectivity on the tumor-affected side was observed, as compared to the unaffected side. Conclusion: Resting fMRI and connectivity analysis are useful in the presurgical evaluation of patients with brain tumors and may help in uncooperative or pediatric patients. They can also prognosticate the postoperative outcome. This method also has significant applications due to the ease of image acquisition.

  16. Brain MRI findings in patients with mucopolysaccharidosis types I and II and mild clinical presentation

    Energy Technology Data Exchange (ETDEWEB)

    Matheus, M.Gisele; Castillo, Mauricio; Smith, J. Keith [Department of Radiology, University of North Carolina School of Medicine, 27599-7510, Chapel Hill, NC (United States); Armao, Diane [Department of Pathology, University of North Carolina School of Medicine, Chapel Hill, NC (United States); Towle, Diane; Muenzer, Joseph [Department of Genetics and Metabolism, University of North Carolina School of Medicine, Chapel Hill, NC (United States)

    2004-08-01

    Our objective was to determine the brain magnetic resonance imaging (MRI) abnormalities in a selected group of patients with mucopolysaccharidosis (MPS) types I and II who had only mild clinical manifestations. We retrospectively assessed MRI brain studies in 18 patients with MPS (type I: 6 and type II: 12). We evaluated abnormal signal intensity in the white matter, widening of the cortical sulci, size of the supratentorial ventricles, dilatation of the perivascular spaces (PVS) and enlargement of the subarachnoid spaces. We observed a broad spectrum of findings, and despite severely abnormal MRI studies, no patients had mental retardation. We also observed that dilated PVS, previously believed to be caused by macroscopic deposition of the mucopolysaccharides, had an appearance similar to cerebrospinal fluid (CSF) in all MRI sequences performed, even in FLAIR and trace diffusion weighted images. Based on our results, we believe that with the exception of white matter abnormalities and brain atrophy, all other findings may be related to abnormal resorption of CSF, and there is no relationship between the imaging and clinical manifestations of the disease. (orig.)

  17. Evolution and current challenges in the teaching of functional MRI and functional brain imaging.

    Science.gov (United States)

    Savoy, Robert L

    2012-08-15

    The report of any new and successful method for studying the world triggers the need to train people in the use of that method. In the case of functional magnetic resonance imaging and its use for examining human brain function in vivo, expertise is required in a greater collection of domains than usual. Development of fMRI training programs started shortly after the announcement of BOLD-based fMRI in humans. These programs had a variety of durations and primary content areas. All programs had to deal with the challenge of bringing interested researchers from a wide variety of areas-many of whom had little or no understanding of MR physics, and/or experimental psychology, and/or the nuances of data analysis and modeling-to a sufficiently detailed level of knowledge that both the funding agencies, and the existing proprietors of the technology (often radiologists or MR physicists at hospitals) would take the research proposals of new investigators seriously. Now that fMRI-based research is well established, there are new educational challenges. Some have to do with the growing list of technologies used to study human brain function in vivo. But perhaps more daunting is the challenge of training consumers of the reports and claims based on fMRI and other brain imaging modalities. As fMRI becomes influential in contexts beyond the research environment-from the clinic to the courtroom to the legislature-training consumers of fMRI-based claims will take on increasing importance, and represents its own unique challenges for education.

  18. Imaging artifacts induced by electrical stimulation during conventional fMRI of the brain.

    Science.gov (United States)

    Antal, Andrea; Bikson, Marom; Datta, Abhishek; Lafon, Belen; Dechent, Peter; Parra, Lucas C; Paulus, Walter

    2014-01-15

    Functional magnetic resonance imaging (fMRI) of brain activation during transcranial electrical stimulation is used to provide insight into the mechanisms of neuromodulation and targeting of particular brain structures. However, the passage of current through the body may interfere with the concurrent detection of blood oxygen level-dependent (BOLD) signal, which is sensitive to local magnetic fields. To test whether these currents can affect concurrent fMRI recordings we performed conventional gradient echo-planar imaging (EPI) during transcranial direct current (tDCS) and alternating current stimulation (tACS) on two post-mortem subjects. tDCS induced signals in both superficial and deep structures. The signal was specific to the electrode montage, with the strongest signal near cerebrospinal fluid (CSF) and scalp. The direction of change relative to non-stimulation reversed with tDCS stimulation polarity. For tACS there was no net effect of the MRI signal. High-resolution individualized modeling of current flow and induced static magnetic fields suggested a strong coincidence of the change EPI signal with regions of large current density and magnetic fields. These initial results indicate that (1) fMRI studies of tDCS must consider this potentially confounding interference from current flow and (2) conventional MRI imaging protocols can be potentially used to measure current flow during transcranial electrical stimulation. The optimization of current measurement and artifact correction techniques, including consideration of the underlying physics, remains to be addressed.

  19. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Hidekazu (Tokyo Women' s Medical Coll. (Japan))

    1989-06-01

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author).

  20. Brain functions after sports-related concussion: insights from event-related potentials and functional MRI.

    Science.gov (United States)

    Gosselin, Nadia; Saluja, Rajeet Singh; Chen, Jen-Kai; Bottari, Carolina; Johnston, Karen; Ptito, Alain

    2010-10-01

    The high incidence of concussions in contact sports and their impact on brain functions are a major cause for concern. To improve our understanding of brain functioning after sports-related concussion, advanced functional assessment techniques, namely event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI), have been recently used in research studies. Contrary to neuropsychological tests that measure verbal and/or motor responses, ERPs and fMRI assess the neural activities associated with cognitive/behavioral demands, and thus provide access to better comprehension of brain functioning. In fact, ERPs have excellent temporal resolution, and fMRI identifies the involved structures during a task. This article describes ERP and fMRI techniques and reviews the results obtained with these tools in sports-related concussion. Although these techniques are not yet readily available, they offer a unique clinical approach, particularly for complex cases (ie, athletes with multiple concussions, chronic symptoms) and objective measures that provide valuable information to guide management and return-to-play decision making.

  1. Interpreting the effects of altered brain anatomical connectivity on fMRI functional connectivity: a role for computational neural modeling.

    Science.gov (United States)

    Horwitz, Barry; Hwang, Chuhern; Alstott, Jeff

    2013-01-01

    Recently, there have been a large number of studies using resting state fMRI to characterize abnormal brain connectivity in patients with a variety of neurological, psychiatric, and developmental disorders. However, interpreting what the differences in resting state fMRI functional connectivity (rsfMRI-FC) actually reflect in terms of the underlying neural pathology has proved to be elusive because of the complexity of brain anatomical connectivity. The same is the case for task-based fMRI studies. In the last few years, several groups have used large-scale neural modeling to help provide some insight into the relationship between brain anatomical connectivity and the corresponding patterns of fMRI-FC. In this paper we review several efforts at using large-scale neural modeling to investigate the relationship between structural connectivity and functional/effective connectivity to determine how alterations in structural connectivity are manifested in altered patterns of functional/effective connectivity. Because the alterations made in the anatomical connectivity between specific brain regions in the model are known in detail, one can use the results of these simulations to determine the corresponding alterations in rsfMRI-FC. Many of these simulation studies found that structural connectivity changes do not necessarily result in matching changes in functional/effective connectivity in the areas of structural modification. Often, it was observed that increases in functional/effective connectivity in the altered brain did not necessarily correspond to increases in the strength of the anatomical connection weights. Note that increases in rsfMRI-FC in patients have been interpreted in some cases as resulting from neural plasticity. These results suggest that this interpretation can be mistaken. The relevance of these simulation findings to the use of functional/effective fMRI connectivity as biomarkers for brain disorders is also discussed.

  2. Cornelia de Lange syndrome: Correlation of brain MRI findings with behavioral assessment.

    Science.gov (United States)

    Roshan Lal, Tamanna R; Kliewer, Mark A; Lopes, Thelma; Rebsamen, Susan L; O'Connor, Julia; Grados, Marco A; Kimball, Amy; Clemens, Julia; Kline, Antonie D

    2016-06-01

    Neurobehavioral and developmental issues with a broad range of deficits are prominent features of Cornelia de Lange syndrome (CdLS), a disorder due to disruption of the cohesin protein complex. The etiologic relationship of these clinical findings to anatomic abnormalities on neuro-imaging studies has not, however, been established. Anatomic abnormalities in the brain and central nervous system specific to CdLS have been observed, including changes in the white matter, brainstem, and cerebellum. We hypothesize that location and severity of brain abnormalities correlate with clinical phenotype in CdLS, as seen in other developmental disorders. In this study, we retrospectively evaluated brain MRI studies of 15 individuals with CdLS and compared these findings to behavior at the time of the scan. Behavior was assessed using the Aberrant Behavior Checklist (ABC), a validated behavioral assessment tool with several clinical features. Ten of fifteen (67%) of CdLS patients had abnormal findings on brain MRI, including cerebral atrophy, white matter changes, cerebellar hypoplasia, and enlarged ventricles. Other findings included pituitary tumors or cysts, Chiari I malformation and gliosis. Abnormal behavioral scores in more than one behavioral area were seen in all but one patient. All 5 of the 15 (33%) patients with normal structural MRI studies had abnormal ABC scores. All normal ABC scores were noted in only one patient and this was correlated with moderately abnormal MRI changes. Although our cohort is small, our results suggest that abnormal behaviors can exist in individuals with CdLS in the setting of relatively normal structural brain findings. © 2016 Wiley Periodicals, Inc.

  3. Simple Fully Automated Group Classification on Brain fMRI

    Energy Technology Data Exchange (ETDEWEB)

    Honorio, J.; Goldstein, R.; Honorio, J.; Samaras, D.; Tomasi, D.; Goldstein, R.Z.

    2010-04-14

    We propose a simple, well grounded classification technique which is suited for group classification on brain fMRI data sets that have high dimensionality, small number of subjects, high noise level, high subject variability, imperfect registration and capture subtle cognitive effects. We propose threshold-split region as a new feature selection method and majority voteas the classification technique. Our method does not require a predefined set of regions of interest. We use average acros ssessions, only one feature perexperimental condition, feature independence assumption, and simple classifiers. The seeming counter-intuitive approach of using a simple design is supported by signal processing and statistical theory. Experimental results in two block design data sets that capture brain function under distinct monetary rewards for cocaine addicted and control subjects, show that our method exhibits increased generalization accuracy compared to commonly used feature selection and classification techniques.

  4. Risk of multiple sclerosis after optic neuritis in patients with normal baseline brain MRI.

    Science.gov (United States)

    Marques, Inês Brás; Matias, Fernando; Silva, Eduardo Duarte; Cunha, Luis; Sousa, Lívia

    2014-04-01

    When assessing and managing a patient with optic neuritis (ON), the risk of future development of multiple sclerosis (MS) is an important issue, as this can be the first presentation of the disease. Although the presence of lesions on baseline brain MRI is the strongest predictor of MS conversion, some patients with normal imaging also develop MS. We aimed to estimate MS risk in patients with ON and a normal baseline MRI and identify individuals with higher risk of conversion. We performed a retrospective study including patients with idiopathic ON and normal baseline brain MRI who presented to our hospital over an 8 year period. Of a total of 42 patients, 10 converted to MS: five during the first follow-up year, seven during the first 2 years and all of the patients within the first 5 years, with a 5 year MS conversion rate of 23.8%. MS conversion rates were significantly higher in patients with history of previous symptoms suggestive of demyelination (p=0.002), cerebrospinal fluid oligoclonal bands unmatched in serum (p=0.004) and incomplete visual acuity recovery (≤6/12) after 1 year (p=0.002). Lower conversion rates were found in patients with optic disc edema (p=0.022). According to these results, a significant proportion of patients with idiopathic ON and a normal baseline brain MRI will develop MS, with a higher risk during the first 5 years. Therefore, in the presence of factors in favor of MS conversion, close follow-up, including semestral medical consultations and yearly brain MRI, can be recommended. Early immunomodulatory treatment may be individually considered as it can delay conversion and reduce new lesion development rate.

  5. Assessment of cognitive brain function in ecstasy users and contributions of other drugs of abuse : Results from an fMRI study

    NARCIS (Netherlands)

    Jager, Gerry; de Win, Maartje M. L.; van der Tweel, Ingeborg; Schilt, Thelma; Kahn, Rene S.; van den Brink, Wim; van Ree, Jan M.; Ramsey, Nick F.

    2008-01-01

    Heavy ecstasy use has been associated with neurocognitive deficits in various behavioral and brain imaging studies. However, this association is not conclusive owing to the unavoidable confounding factor of polysubstance use. The present study, as part of the Netherlands XTC Toxicity study, investig

  6. Aberrant brain regional homogeneity and functional connectivity in middle-aged T2DM patients: a resting-state functional MRI study

    Directory of Open Access Journals (Sweden)

    Daihong Liu

    2016-09-01

    Full Text Available Type 2 diabetes mellitus (T2DM has been associated with cognitive impairment. However, its neurological mechanism remains elusive. Combining regional homogeneity (ReHo and functional connectivity (FC analyses, the present study aimed to investigate brain functional alterations in middle-aged T2DM patients, which could provide complementary information for the neural substrates underlying T2DM-associated brain dysfunction. Twenty-five T2DM patients and 25 healthy controls were involved in neuropsychological testing and structural and resting-state functional magnetic resonance imaging data acquisition. ReHo analysis was conducted to determine the peak coordinates of brain regions with abnormal local brain activity synchronization. Then, the identified brain regions were considered as seeds, and FC between these brain regions and global voxels was computed. Finally, the potential correlations between the imaging indices and neuropsychological data were also explored. Compared with healthy controls, T2DM patients exhibited higher ReHo values in the anterior cingulate gyrus and lower ReHo in right fusiform gyrus, right precentral gyrus and right medial orbit of the superior frontal gyrus. Considering these areas as seed regions, T2DM patients displayed aberrant FC, mainly in the frontal and parietal lobes. The pattern of FC alterations in T2DM patients was characterized by decreased connectivity and positive to negative or negative to positive converted connectivity. Digital Span Test forward scores revealed significant correlations with the ReHo values of the right precentral gyrus (ρ = 0.527, p = 0.014 and FC between the right fusiform gyrus and middle temporal gyrus (ρ = -0.437, p = 0.048. Our findings suggest that T2DM patients suffer from cognitive dysfunction related to spatially local and remote brain activity synchronization impairment. The patterns of ReHo and FC alterations shed light on the mechanisms underlying T2DM-associated brain

  7. Altered baseline brain activity in experts measured by amplitude of low frequency fluctuations (ALFF): a resting state fMRI study using expertise model of acupuncturists.

    Science.gov (United States)

    Dong, Minghao; Li, Jun; Shi, Xinfa; Gao, Shudan; Fu, Shijun; Liu, Zongquan; Liang, Fanrong; Gong, Qiyong; Shi, Guangming; Tian, Jie

    2015-01-01

    It is well established that expertise modulates evoked brain activity in response to specific stimuli. Recently, researchers have begun to investigate how expertise influences the resting brain. Among these studies, most focused on the connectivity features within/across regions, i.e., connectivity patterns/strength. However, little concern has been given to a more fundamental issue whether or not expertise modulates baseline brain activity. We investigated this question using amplitude of low-frequency (expertise model, i.e., acupuncturists, due to their robust proficiency in tactile perception and emotion regulation. After the psychophysical and behavioral expertise screening procedure, 23 acupuncturists and 23 matched non-acupuncturists (NA) were enrolled. Our results explicated higher ALFF for acupuncturists in the left ventral medial prefrontal cortex (VMPFC) and the contralateral hand representation of the primary somatosensory area (SI) (corrected for multiple comparisons). Additionally, ALFF of VMPFC was negatively correlated with the outcomes of the emotion regulation task (corrected for multiple comparisons). We suggest that our study may reveal a novel connection between the neuroplasticity mechanism and resting state activity, which would upgrade our understanding of the central mechanism of learning. Furthermore, by showing that expertise can affect the baseline brain activity as indicated by ALFF, our findings may have profound implication for functional neuroimaging studies especially those involving expert models, in that difference in baseline brain activity may either smear the spatial pattern of activations for task data or introduce biased results into connectivity-based analysis for resting data.

  8. Fractality in the neuron axonal topography of the human brain based on 3-D diffusion MRI

    Science.gov (United States)

    Katsaloulis, P.; Ghosh, A.; Philippe, A. C.; Provata, A.; Deriche, R.

    2012-05-01

    In this work the fractal architecture of the neuron axonal topography of the human brain is evaluated, as derived from 3-D diffusion MRI (dMRI) acquisitions. This is a 3D extension of work performed previously in 2D regions of interest (ROIs), where the fractal dimension of the neuron axonal topography was computed from dMRI data. A group study with 18 subjects is here conducted and the fractal dimensions D f of the entire 3-D volume of the brains is estimated via the box counting, the correlation dimension and the fractal mass dimension methods. The neuron axon data is obtained using tractography algorithms on diffusion tensor imaging of the brain. We find that all three calculations of D f give consistent results across subjects, namely, they demonstrate fractal characteristics in the short and medium length scales: different fractal exponents prevail at different length scales, an indication of multifractality. We surmise that this complexity stems as a collective property emerging when many local brain units, performing different functional tasks and having different local topologies, are recorded together.

  9. STUDY OF POSTERIOR FOSSA TUMORS BY HIGH RESOLUTION MRI

    Directory of Open Access Journals (Sweden)

    Sree Hari

    2016-01-01

    Full Text Available INTRODUCTION Magnetic Resonance Imaging (MRI is the imaging modality used for the assessment of infratentorial neoplasms. Although Computed Tomography (CT provides better demonstration of small or subtle calcifications within tumors. OBJECTIVES Study is done to assess the potential of MRI in characterisation of different tumors in posterior fossa by evaluating various unenhanced and gadolinium enhanced sequences and to compare high resolution FSE MRI sequences with routine FSE MRI sequences in diagnosing posterior fossa brain tumors. Also correlate findings on Magnetic Resonance Imaging with Pathological diagnosis. MATERIALS AND METHODS A total of 52 patients were diagnosed by CT brain as having posterior fossa brain for a year of 2 years were included in the study. In all studies MR imaging was performed with a clinical 1.5 T system (General electrical medical systems. A dedicated phased-array coil was used. RESULTS The age group ranged from 1 year to 60 years, majority were between 1 to 20 years (39%. Slight male preponderance was seen (males 29, females 23. Commonest tumor encountered in our study was vestibular schwannoma. DWI alone can differentiate different pediatric posterior fossa brain tumors. One case of pilocytic astrocytoma showed solid lesion instead of typical cystic lesion with mural nodule. One case AT-RT showed 2 lesions one in cerebrum, one in CP angle. Common feature being intra-axial lesion involving cerebellum. MRI was able to predict diagnosis in 50 of the 52 tumors. CONCLUSION Magnetic Resonance Imaging was found to be a highly sensitive imaging procedure and method of choice for posterior fossa brain tumors.

  10. Reversible cerebral shrinkage in kwashiorkor: an MRI study.

    Science.gov (United States)

    Gunston, G D; Burkimsher, D; Malan, H; Sive, A A

    1992-08-01

    Protein energy malnutrition is associated with cerebral atrophy which may be detrimental to intellectual development. The aim of this study was to document the anatomical abnormalities which lead to the appearance of cerebral atrophy using magnetic resonance imaging (MRI) in the acute stage of kwashiorkor and to monitor changes during nutritional rehabilitation. Twelve children aged 6 to 37 months requiring admission to hospital for the treatment of kwashiorkor were studied. The children were evaluated clinically, biochemically, and by MRI of their brains on admission and 30 and 90 days later. Brain shrinkage was present in every child on admission. White and grey matter appeared equally affected and the myelination was normal for age. At 90 days, the cerebral changes had resolved in nine and improved substantially in the remainder, by which time serum proteins and weight for age were within the normal range. The findings of this study suggest that brain shrinkage associated with kwashiorkor reverses rapidly with nutritional rehabilitation.

  11. EVALUATION OF BRAIN TUMOURS BY MRI TECHNIQUES AND THEIR HISTOPATHOLOGICAL CORRELATION

    OpenAIRE

    Mohammad Shamim; Reyaz; Anju; Dinesh Kumar; Paricharak

    2014-01-01

    : This study was conducted on thirty patients of brain tumors diagnosed on CT scan/ Conventional MRI. It was performed in the Department of Radiological and PET Imaging, Institute of Nuclear Medicine and Allied Sciences (INMAS), Brig S. K. Mazumdar Marg , Lucknow road, Delhi. Out of thirty patients, 19 patients (63.33%) were male and 11 patients (36.66%) were female. Their ages ranged from 22 to 63 years. The most common presenting symptom was headache followed by seizures...

  12. Altered baseline brain activity in experts measured by amplitude of low frequency fluctuations (ALFF: a resting state fMRI study using expertise model of acupuncturists

    Directory of Open Access Journals (Sweden)

    Minghao eDong

    2015-03-01

    Full Text Available It is well established that expertise modulates evoked brain activity in response to specific stimuli. Recently, researchers have begun to investigate how expertise influences the resting brain. Among these studies, most focused on the connectivity features within/across regions, i.e. connectivity patterns/strength. However, little concern has been given to a more fundamental issue whether or not expertise modulates baseline brain activity. We investigated this question using amplitude of low-frequency (<0.08Hz fluctuation (ALFF as the metric of brain activity and a novel expertise model, i.e. acupuncturists, due to their robust proficiency in tactile perception and emotion regulation. After the psychophysical and behavioral expertise screening procedure, 23 acupuncturists and 23 matched non-acupuncturists (NA were enrolled. Our results explicated higher ALFF for acupuncturists in the left ventral medial prefrontal cortex (VMPFC and the contralateral hand representation of the primary somatosensory area (SI (corrected for multiple comparisons. Additionally, ALFF of VMPFC was negatively correlated with the outcomes of the emotion regulation task (corrected for multiple comparisons. We suggest that our study may reveal a novel connection between the neuroplasticity mechanism and resting state activity, which would upgrade our understanding of the central mechanism of learning. Furthermore, by showing that expertise can affect the baseline brain activity as indicated by ALFF, our findings may have profound implication for functional neuroimaging studies especially those involving expert models, in that difference in baseline brain activity may either smear the spatial pattern of activations for task data or introduce biased results into connectivity-based analysis for resting data.

  13. Structural linear measurements in the newborn brain: accuracy of cranial ultrasound compared to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Leijser, Lara M. [Hammersmith Hospital, Imperial College, Department of Paediatrics, London (United Kingdom); Srinivasan, Latha; Cowan, Frances M. [Hammersmith Hospital, Imperial College, Department of Paediatrics, London (United Kingdom); Hammersmith Hospital, Imperial College, Department of Imaging Sciences, London (United Kingdom); Rutherford, Mary A.; Counsell, Serena J.; Allsop, Joanna M. [Hammersmith Hospital, Imperial College, Department of Imaging Sciences, London (United Kingdom)

    2007-07-15

    Structural size in the neonatal brain is of clinical importance. Cranial ultrasonography (cUS) is the primary method used for evaluating the neonatal brain and it is important to know whether linear measurements made using this technique are accurate. To compare linear measurements of different cerebral structures made from neonatal cUS and contemporaneous MRI. Preterm and term infants studies with cUS and MRI on the same day were studied. Linear measurements made using both techniques from many cerebral structures were compared using a paired t-test. A total of 44 sets of scans from 26 preterm and 8 term infants were assessed. Small but significant differences between the cUS and MRI measurements (P<0.05) were found for the ventricular index, the posterior horn depth of the lateral ventricle, the extracerebral space and interhemispheric fissure, and the cortex of the cingulate gyrus. No significant differences were found for any other measurements. Linear measurements from cUS are accurate for most neonatal cerebral structures. Significant differences compared to MRI were found for a few structures, but only for the cortex were the absolute differences marked and possibly of clinical importance. (orig.)

  14. EVALUATION OF BRAIN TUMOURS BY MRI TECHNIQUES AND THEIR HISTOPATHOLOGICAL CORRELATION

    Directory of Open Access Journals (Sweden)

    Mohammad Shamim

    2014-12-01

    Full Text Available : This study was conducted on thirty patients of brain tumors diagnosed on CT scan/ Conventional MRI. It was performed in the Department of Radiological and PET Imaging, Institute of Nuclear Medicine and Allied Sciences (INMAS, Brig S. K. Mazumdar Marg , Lucknow road, Delhi. Out of thirty patients, 19 patients (63.33% were male and 11 patients (36.66% were female. Their ages ranged from 22 to 63 years. The most common presenting symptom was headache followed by seizures. MRI is a powerful tool for evaluation and characterization of brain tumors because of its superior soft tissue contrast and multiplanar capabilities. All these patients underwent routine MRI sequences, including T1W, T2WI and FLAIR sequences. Histopathological correlation was obtained in all the patients to serve as the gold standard. Out of thirty patients selected for this study, twenty cases were found to be malignant and ten cases were benign on histopathological evaluation. Majority of malignant lesions were glioblastomamultiforme. Amongst benign cases, majorities were meningioma, one was a granulomatous lesion and one was a benign cystic lesion. On conventional MRI sequences, including T1, T2 and FLAIR, there was significant overlap between appearances of benign and malignant lesions in their intensity on various sequences. Moreover, it has got no prognostic value in follow up of patients after therapy.

  15. A template of rat brain based on fMRI T2* imaging

    Institute of Scientific and Technical Information of China (English)

    HU Zhenghui; WU Yigen; WANG Xiaochuan; WANG Jianzhi; CHEN Feiyan; TANG Xiaowei

    2005-01-01

    The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

  16. Brain size and white matter content of cerebrospinal tracts determine the upper cervical cord area: evidence from structural brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Christina; Arsic, Milan; Boucard, Christine C.; Biberacher, Viola; Nunnemann, Sabine; Muehlau, Mark [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center, Klinikum rechts der Isar, Munich (Germany); Schmidt, Paul [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Ludwig-Maximilians-University Muenchen, Department of Statistics, Munich (Germany); Roettinger, Michael [Technische Universitaet Muenchen, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Muenchner Institut fuer Neuroradiologie, Munich (Germany); Etgen, Thorleif [Technische Universitaet Muenchen, Department of Neurology, Klinikum rechts der Isar, Munich (Germany); Klinikum Traunstein, Department of Neurology, Traunstein (Germany); Koutsouleris, Nikolaos; Meisenzahl, Eva M. [Ludwig-Maximilians-Universitaet Muenchen, Department of Psychiatry and Psychotherapy, Munich (Germany); Reiser, Maximilian [Ludwig-Maximilians-Universitaet, Department of Radiology, Munich (Germany)

    2013-08-15

    Measurement of the upper cervical cord area (UCCA) from brain MRI may be an effective way to quantify spinal cord involvement in neurological disorders such as multiple sclerosis. However, knowledge on the determinants of UCCA in healthy controls (HCs) is limited. In two cohorts of 133 and 285 HCs, we studied the influence of different demographic, body-related, and brain-related parameters on UCCA by simple and partial correlation analyses as well as by voxel-based morphometry (VBM) across both cerebral gray matter (GM) and white matter (WM). First, we confirmed the known but moderate effect of age on UCCA in the older cohort. Second, we studied the correlation of UCCA with sex, body height, and total intracranial volume (TIV). TIV was the only variable that correlated significantly with UCCA after correction for the other variables. Third, we studied the correlation of UCCA with brain-related parameters. Brain volume correlated stronger with UCCA than TIV. Both volumes of the brain tissue compartments GM and WM correlated with UCCA significantly. WM volume explained variance of UCCA after correction for GM volume, whilst the opposite was not observed. Correspondingly, VBM did not yield any brain region, whose GM content correlated significantly with UCCA, whilst cerebral WM content of cerebrospinal tracts strongly correlated with UCCA. This latter effect increased along a craniocaudal gradient. UCCA is mainly determined by brain volume as well as by WM content of cerebrospinal tracts. (orig.)

  17. Discriminating between brain rest and attention states using fMRI connectivity graphs and subtree SVM

    Science.gov (United States)

    Mokhtari, Fatemeh; Bakhtiari, Shahab K.; Hossein-Zadeh, Gholam Ali; Soltanian-Zadeh, Hamid

    2012-02-01

    Decoding techniques have opened new windows to explore the brain function and information encoding in brain activity. In the current study, we design a recursive support vector machine which is enriched by a subtree graph kernel. We apply the classifier to discriminate between attentional cueing task and resting state from a block design fMRI dataset. The classifier is trained using weighted fMRI graphs constructed from activated regions during the two mentioned states. The proposed method leads to classification accuracy of 1. It is also able to elicit discriminative regions and connectivities between the two states using a backward edge elimination algorithm. This algorithm shows the importance of regions including cerebellum, insula, left middle superior frontal gyrus, post cingulate cortex, and connectivities between them to enhance the correct classification rate.

  18. MRI-detectable changes in mouse brain structure induced by voluntary exercise.

    Science.gov (United States)

    Cahill, Lindsay S; Steadman, Patrick E; Jones, Carly E; Laliberté, Christine L; Dazai, Jun; Lerch, Jason P; Stefanovic, Bojana; Sled, John G

    2015-06-01

    Physical exercise, besides improving cognitive and mental health, is known to cause structural changes in the brain. Understanding the structural changes that occur with exercise as well as the neuroanatomical correlates of a predisposition for exercise is important for understanding human health. This study used high-resolution 3D MR imaging, in combination with deformation-based morphometry, to investigate the macroscopic changes in brain structure that occur in healthy adult mice following four weeks of voluntary exercise. We found that exercise induced changes in multiple brain structures that are involved in motor function and learning and memory including the hippocampus, dentate gyrus, stratum granulosum of the dentate gyrus, cingulate cortex, olivary complex, inferior cerebellar peduncle and regions of the cerebellum. In addition, a number of brain structures, including the hippocampus, striatum and pons, when measured on MRI prior to the start of exercise were highly predictive of subsequent exercise activity. Exercise tended to normalize these pre-existing differences between mice.

  19. Mapping the mouse brain with rs-fMRI: An optimized pipeline for functional network identification.

    Science.gov (United States)

    Zerbi, Valerio; Grandjean, Joanes; Rudin, Markus; Wenderoth, Nicole

    2015-12-01

    The use of resting state fMRI (rs-fMRI) in translational research is a powerful tool to assess brain connectivity and investigate neuropathology in mouse models. However, despite encouraging initial results, the characterization of consistent and robust resting state networks in mice remains a methodological challenge. One key reason is that the quality of the measured MR signal is degraded by the presence of structural noise from non-neural sources. Notably, in the current pipeline of the Human Connectome Project, a novel approach has been introduced to clean rs-fMRI data, which involves automatic artifact component classification and data cleaning (FIX). FIX does not require any external recordings of physiology or the segmentation of CSF and white matter. In this study, we evaluated the performance of FIX for analyzing mouse rs-fMRI data. Our results showed that FIX can be easily applied to mouse datasets and detects true signals with 100% accuracy and true noise components with very high accuracy (>98%), thus reducing both within- and between-subject variability of rs-fMRI connectivity measurements. Using this improved pre-processing pipeline, maps of 23 resting state circuits in mice were identified including two networks that displayed default mode network-like topography. Hierarchical clustering grouped these neural networks into meaningful larger functional circuits. These mouse resting state networks, which are publicly available, might serve as a reference for future work using mouse models of neurological disorders.

  20. Genetic influences of resting state fMRI activity in language-related brain regions in healthy controls and schizophrenia patients: a pilot study.

    Science.gov (United States)

    Jamadar, Sharna; Powers, Natalie R; Meda, Shashwath A; Calhoun, Vince D; Gelernter, Joel; Gruen, Jeffrey R; Pearlson, Godfrey D

    2013-03-01

    Individuals with schizophrenia show a broad range of language impairments, similar to those observed in reading disability (RD). Genetic linkage and association studies of RD have identified a number of candidate RD-genes that are associated with neuronal migration. Some individuals with schizophrenia also show evidence of impaired cortical neuronal migration. We have previously linked RD-related genes with gray matter distributions in healthy controls and schizophrenia. The aim of the current study was to extend these structural findings and to examine links between putative RD-genes and functional connectivity of language-related regions in healthy controls (n = 27) and schizophrenia (n = 28). Parallel independent component analysis (parallel-ICA) was used to examine the relationship between language-related regions extracted from resting-state fMRI and 16 single nucleotide polymorphisms (SNPs) spanning 5 RD-related genes. Parallel-ICA identified four significant fMRI-SNP relationships. A Left Broca-Superior/Inferior Parietal network was related to two KIAA0319 SNPs in controls but not in schizophrenia. For both diagnostic groups, a Broca-Medial Parietal network was related to two DCDC2 SNPs, while a Left Wernicke-Fronto-Occipital network was related to two KIAA0319 SNPs. A Bilateral Wernicke-Fronto-Parietal network was related to one KIAA0319 SNP only in controls. Thus, RD-genes influence functional connectivity in language-related regions, but no RD-gene uniquely affected network function in schizophrenia as compared to controls. This is in contrast with our previous study where RD-genes affected gray matter distribution in some structural networks in schizophrenia but not in controls. Thus these RD-genes may exert a more important influence on structure rather than function of language-related networks in schizophrenia.

  1. Functional MRI Preprocessing in Lesioned Brains: Manual Versus Automated Region of Interest Analysis.

    Science.gov (United States)

    Garrison, Kathleen A; Rogalsky, Corianne; Sheng, Tong; Liu, Brent; Damasio, Hanna; Winstein, Carolee J; Aziz-Zadeh, Lisa S

    2015-01-01

    Functional magnetic resonance imaging (fMRI) has significant potential in the study and treatment of neurological disorders and stroke. Region of interest (ROI) analysis in such studies allows for testing of strong a priori clinical hypotheses with improved statistical power. A commonly used automated approach to ROI analysis is to spatially normalize each participant's structural brain image to a template brain image and define ROIs using an atlas. However, in studies of individuals with structural brain lesions, such as stroke, the gold standard approach may be to manually hand-draw ROIs on each participant's non-normalized structural brain image. Automated approaches to ROI analysis are faster and more standardized, yet are susceptible to preprocessing error (e.g., normalization error) that can be greater in lesioned brains. The manual approach to ROI analysis has high demand for time and expertise, but may provide a more accurate estimate of brain response. In this study, commonly used automated and manual approaches to ROI analysis were directly compared by reanalyzing data from a previously published hypothesis-driven cognitive fMRI study, involving individuals with stroke. The ROI evaluated is the pars opercularis of the inferior frontal gyrus. Significant differences were identified in task-related effect size and percent-activated voxels in this ROI between the automated and manual approaches to ROI analysis. Task interactions, however, were consistent across ROI analysis approaches. These findings support the use of automated approaches to ROI analysis in studies of lesioned brains, provided they employ a task interaction design.

  2. scMRI reveals large-scale brain network abnormalities in autism.

    Directory of Open Access Journals (Sweden)

    Brandon A Zielinski

    Full Text Available Autism is a complex neurological condition characterized by childhood onset of dysfunction in multiple cognitive domains including socio-emotional function, speech and language, and processing of internally versus externally directed stimuli. Although gross brain anatomic differences in autism are well established, recent studies investigating regional differences in brain structure and function have yielded divergent and seemingly contradictory results. How regional abnormalities relate to the autistic phenotype remains unclear. We hypothesized that autism exhibits distinct perturbations in network-level brain architecture, and that cognitive dysfunction may be reflected by abnormal network structure. Network-level anatomic abnormalities in autism have not been previously described. We used structural covariance MRI to investigate network-level differences in gray matter structure within two large-scale networks strongly implicated in autism, the salience network and the default mode network, in autistic subjects and age-, gender-, and IQ-matched controls. We report specific perturbations in brain network architecture in the salience and default-mode networks consistent with clinical manifestations of autism. Extent and distribution of the salience network, involved in social-emotional regulation of environmental stimuli, is restricted in autism. In contrast, posterior elements of the default mode network have increased spatial distribution, suggesting a 'posteriorization' of this network. These findings are consistent with a network-based model of autism, and suggest a unifying interpretation of previous work. Moreover, we provide evidence of specific abnormalities in brain network architecture underlying autism that are quantifiable using standard clinical MRI.

  3. Endoscopy-verified occult subependymal dissemination of glioblastoma and brain metastasis undetected by MRI: prognostic significance

    Directory of Open Access Journals (Sweden)

    Iacoangeli M

    2012-12-01

    Full Text Available Maurizio Iacoangeli,1 Alessandro Di Rienzo,1 Roberto Colasanti,1 Antonio Zizzi,2 Maurizio Gladi,1 Lorenzo Alvaro,1 Niccolò Nocchi,1 Lucia Giovanna Maria Di Somma,1 Marina Scarpelli,2 Massimo Scerrati11Department of Neurosurgery, 2Department of Pathology, Università Politecnica delle Marche, Umberto I General Hospital, Ancona, ItalyAbstract: Although various prognostic indices exist for patients with malignant brain tumors, the prognostic significance of the subependymal spread of intracranial tumors is still a matter of debate. In this paper, we report the cases of two intraventricular lesions, a recurrent glioblastoma multiforme (GBM and a brain metastasis, each successfully treated with a neuroendoscopic approach. Thanks to this minimally invasive approach, we achieved good therapeutic results: we obtained a histological diagnosis; we controlled intracranial hypertension by treating the associated hydrocephalus and, above all, compared with a microsurgical approach, we reduced the risks related to dissection and brain retraction. Moreover, in both cases, neuroendoscopy enabled us to identify an initial, precocious subependymal tumor spreading below the threshold of magnetic resonance imaging (MRI detection. This finding, undetected in pre-operative MRI scans, was then evident during follow-up neuroimaging studies. In light of these data, a neuroendoscopic approach might play a leading role in better defining the prognosis and optimally tailored management protocols for GBM and brain metastasis.Keywords: subependymal spreading, glioblastoma, brain metastasis, endoscopy, minimally invasive surgery, prognosis

  4. Registration and display of brain SPECT and MRI using external markers.

    Science.gov (United States)

    Pohjonen, H; Nikkinen, P; Sipilä, O; Launes, J; Salli, E; Salonen, O; Karp, P; Ylä-Jääski, J; Katila, T; Liewendahl, K

    1996-02-01

    Accurate anatomical localisation of abnormalities observed in brain perfusion single-photon emission computed tomography (SPECT) is difficult, but can be improved by correlating data from SPECT and other tomographic imaging modalities. For this purpose we have developed software to register, analyse and display 99mTc-hexamethylpropyleneamine oxime SPECT and 1.0 T MRI of the brain. For registration of SPECT and MRI data external skin markers containing 99mTc (220 kBq) in 50 microliters of coconut butter were used. The software is coded in the C programming language, and the X Window system and the OSF/Motif standards are used for graphics and definition of the user interface. The registration algorithm follows a noniterative least-squares method using singular value decomposition of a 3 x 3 covariance matrix. After registration, the image slices of both data sets are shown at identical tomographic levels. The registration error in phantom studies was on average 4 mm. In the two-dimensional display mode the orthogonal cross-sections of the data sets are displayed side by side. In the three-dimensional mode MRI data are displayed as a surface-shaded 3 D reconstruction and SPECT data as cut planes. The usefulness of this method is demonstrated in patients with cerebral infarcts, brain tumour, herpes simplex encephalitis and epilepsy.

  5. Registration and display of brain SPECT and MRI using external markers

    Energy Technology Data Exchange (ETDEWEB)

    Pohjonen, H. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland); Nikkinen, P. [Department of Clinical Chemistry, Division of Nuclear Medicine, Helsinki University Central Hospital, Helsinki (Finland); Sipilae, O. [Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Launes, J. [Department of Neurology, Helsinki University Central Hospital, Helsinki (Finland); Salli, E. [Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Salonen, O. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Karp, P. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland); Ylae-Jaeaeski, J. [Graphic Arts Laboratory, Technical Research Centre of Finland, Espoo (Finland); Katila, T. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland)]|[Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Liewendahl, K. [Department of Clinical Chemistry, Division of Nuclear Medicine, Helsinki University Central Hospital, Helsinki (Finland)

    1996-02-01

    Accurate anatomical localisation of abnormalities observed in brain perfusion single-photon emission computed tomography (SPECT) is difficult, but can be improved by correlating data from SPECT and other tomographic imaging modalities. For this purpose we have developed software to register, analyse and display {sup 99m}Tc-hexamethylpropyleneamine oxime SPECT and 1.0 T MRI of the brain. For registration of SPECT and MRI data external skin markers containing {sup 99m}Tc (220 kBq) in 50 {mu}l of coconut butter were used. The software is coded in the C programming language, and the X Window system and the OSF/Motif standards are used for graphics and definition of the user interface. The registration algorithm follows a noniterative least-squares method using singular value decomposition of a 3 x 3 covariance matrix. After registration, the image slices of both data sets are shown at identical tomographic levels. The registration error in phantom studies was on average 4 mm. In the two-dimensional display mode the orthogonal cross-sections of the data sets are displayed side by side. In the three-dimensional mode MRI data are displayed as a surface-shaded 3 D reconstruction and SPECT data as cut planes. The usefulness of this method is demonstrated in patients with cerebral infarcts, brain tumour, herpes simplex encephalitis and epilepsy. (orig.). With 9 figs.

  6. Brain and behaviour in children with 22q11.2 deletion syndrome: a volumetric and voxel-based morphometry MRI study.

    Science.gov (United States)

    Campbell, Linda E; Daly, Eileen; Toal, Fiona; Stevens, Angela; Azuma, Rayna; Catani, Marco; Ng, Virginia; van Amelsvoort, Therese; Chitnis, Xavier; Cutter, William; Murphy, Declan G M; Murphy, Kieran C

    2006-05-01

    In people with velo-cardio-facial syndrome [or 22q11.2 deletion syndrome (22qDS)], a single interstitial deletion of chromosome 22q11.2 causes a wide spectrum of cognitive deficits ranging from global learning difficulties to specific cognitive deficits. People with 22qDS are also at high risk of developing attention-deficit/hyperactivity disorder and autism spectrum disorders in childhood, and schizophrenia in adolescence or adult life. However, the neurobiology of 22qDS, and the relationship between abnormalities in brain anatomy and behaviour, is poorly understood. Thus, we studied the neuroanatomy of 22qDS children using fully automated voxel-based morphometry (VBM) and manually traced single region-of-interest (ROI) analysis. Also, we investigated whether those brain regions that differed significantly between groups were related to behavioural differences within children with 22qDS. We compared the brain morphometry of 39 children and adolescents with 22qDS (mean age: 11 years, SD +/-3, IQ = 67, SD +/-10) and 26 sibling controls (mean age: 11 years, SD +/-3, IQ = 102, SD +/-12). Using VBM, we found, after correction for IQ, that individuals with 22qDS compared with controls had a significant reduction in cerebellar grey matter, and white matter reductions in the frontal lobe, cerebellum and internal capsule. Using single ROI analysis, we found that people with 22qDS had a significant (P social behavioural difficulties and grey matter in frontostriatal regions. Thus, subjects with 22qDS have widespread changes in brain anatomy, particularly affecting white matter, basal ganglia and cerebellum. Also, within 22qDS, regionally specific differences in brain development may partially underpin behavioural differences. We suggest that there is preliminary evidence for specific vulnerability of the frontostriatal and cerebellar-cortical networks in 22qDS.

  7. Structural MRI of Pediatric Brain Development: What Have We Learned and Where Are We Going?

    OpenAIRE

    2010-01-01

    Magnetic resonance imaging (MRI) allows unprecedented access to the anatomy and physiology of the developing brain without the use of ionizing radiation. Over the past two decades, thousands of brain MRI scans from healthy youth and those with neuropsychiatric illness have been acquired and analyzed with respect to diagnosis, sex, genetics, and/or psychological variables such as IQ. Initial reports comparing size differences of various brain components averaged across large age spans have giv...

  8. Biophysical modeling of high field diffusion MRI demonstrates micro-structural aberration in chronic mild stress rat brain.

    Science.gov (United States)

    Khan, Ahmad Raza; Chuhutin, Andrey; Wiborg, Ove; Kroenke, Christopher D; Nyengaard, Jens R; Hansen, Brian; Jespersen, Sune Nørhøj

    2016-11-15

    Depression is one of the leading causes of disability worldwide. Immense heterogeneity in symptoms of depression causes difficulty in diagnosis, and to date, there are no established biomarkers or imaging methods to examine depression. Unpredictable chronic mild stress (CMS) induced anhedonia is considered to be a realistic model of depression in studies of animal subjects. Stereological and neuronal tracing techniques have demonstrated persistent remodeling of microstructure in hippocampus, prefrontal cortex and amygdala of CMS brains. Recent developments in diffusion MRI (d-MRI) analyses, such as neurite density and diffusion kurtosis imaging (DKI), are able to capture microstructural changes and are considered to be robust tools in preclinical and clinical imaging. The present study utilized d-MRI analyzed with a neurite density model and the DKI framework to investigate microstructure in the hippocampus, prefrontal cortex, caudate putamen and amygdala regions of CMS rat brains by comparison to brains from normal controls. To validate findings of CMS induced microstructural alteration, histology was performed to determine neurite, nuclear and astrocyte density. d-MRI based neurite density and tensor-based mean kurtosis (MKT) were significantly higher, while mean diffusivity (MD), extracellular diffusivity (Deff) and intra-neurite diffusivity(DL) were significantly lower in the amygdala of CMS rat brains. Deff was also significantly lower in the hippocampus and caudate putamen in stressed groups. Histological neurite density corroborated the d-MRI findings in the amygdala and reductions in nuclear and astrocyte density further buttressed the d-MRI results. The present study demonstrated that the d-MRI based neurite density and MKT can reveal specific microstructural changes in CMS rat brains and these parameters might have value in clinical diagnosis of depression and for evaluation of treatment efficacy.

  9. Scent of the familiar: an fMRI study of canine brain responses to familiar and unfamiliar human and dog odors.

    Science.gov (United States)

    Berns, Gregory S; Brooks, Andrew M; Spivak, Mark

    2015-01-01

    Understanding dogs' perceptual experience of both conspecifics and humans is important to understand how dogs evolved and the nature of their relationships with humans and other dogs. Olfaction is believed to be dogs' most powerful and perhaps important sense and an obvious place to begin for the study of social cognition of conspecifics and humans. We used fMRI in a cohort of dogs (N=12) that had been trained to remain motionless while unsedated and unrestrained in the MRI. By presenting scents from humans and conspecifics, we aimed to identify the dimensions of dogs' responses to salient biological odors - whether they are based on species (dog or human), familiarity, or a specific combination of factors. We focused our analysis on the dog's caudate nucleus because of its well-known association with positive expectations and because of its clearly defined anatomical location. We hypothesized that if dogs' primary association to reward, whether it is based on food or social bonds, is to humans, then the human scents would activate the caudate more than the conspecific scents. Conversely, if the smell of conspecifics activated the caudate more than the smell of humans, dogs' association to reward would be stronger to their fellow canines. Five scents were presented (self, familiar human, strange human, familiar dog, strange dog). While the olfactory bulb/peduncle was activated to a similar degree by all the scents, the caudate was activated maximally to the familiar human. Importantly, the scent of the familiar human was not the handler, meaning that the caudate response differentiated the scent in the absence of the person being present. The caudate activation suggested that not only did the dogs discriminate that scent from the others, they had a positive association with it. This speaks to the power of the dog's sense of smell, and it provides important clues about the importance of humans in dogs' lives. This article is part of a Special Issue entitled: Canine

  10. Localization of the brain calculation function area with MRI

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The aim of this study is to define the anatomical localization of corresponding brain function area during calculating. The activating modes in brain during continuous silent calculating subtraction and repeated silent reading multiplication table were compared and investigated. Fourteen volunteers of right-handedness were enrolled in this experiment. The quite difference of reaction modes in brain area during the two modes of calculation reveal that there are different processing pathways in brain during these two operating actions. During continuous silent calculating, the function area is localized on the posterior portion of superior and middle gyrus of frontal lobe and the Iobule of posterior parietal lobe (P < 0.01, T = 5.41). It demonstrates that these function areas play an important role in the performance of calculation and working memory. Whereas the activating of visual cortex shows that even in mental arithmetic processing the brain action is having the aid of vision and visual space association.

  11. Restoring susceptibility induced MRI signal loss in rat brain at 9.4 T: A step towards whole brain functional connectivity imaging.

    Directory of Open Access Journals (Sweden)

    Rupeng Li

    Full Text Available The aural cavity magnetic susceptibility artifact leads to significant echo planar imaging (EPI signal dropout in rat deep brain that limits acquisition of functional connectivity fcMRI data. In this study, we provide a method that recovers much of the EPI signal in deep brain. Needle puncture introduction of a liquid-phase fluorocarbon into the middle ear allows acquisition of rat fcMRI data without signal dropout. We demonstrate that with seeds chosen from previously unavailable areas, including the amygdala and the insular cortex, we are able to acquire large scale networks, including the limbic system. This tool allows EPI-based neuroscience and pharmaceutical research in rat brain using fcMRI that was previously not feasible.

  12. Relative value of diverse brain MRI and blood-based biomarkers for predicting cognitive decline in the elderly

    Science.gov (United States)

    Madsen, Sarah K.; Ver Steeg, Greg; Daianu, Madelaine; Mezher, Adam; Jahanshad, Neda; Nir, Talia M.; Hua, Xue; Gutman, Boris A.; Galstyan, Aram; Thompson, Paul M.

    2016-03-01

    Cognitive decline accompanies many debilitating illnesses, including Alzheimer's disease (AD). In old age, brain tissue loss also occurs along with cognitive decline. Although blood tests are easier to perform than brain MRI, few studies compare brain scans to standard blood tests to see which kinds of information best predict future decline. In 504 older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we first used linear regression to assess the relative value of different types of data to predict cognitive decline, including 196 blood panel biomarkers, 249 MRI biomarkers obtained from the FreeSurfer software, demographics, and the AD-risk gene APOE. A subset of MRI biomarkers was the strongest predictor. There was no specific blood marker that increased predictive accuracy on its own, we found that a novel unsupervised learning method, CorEx, captured weak correlations among blood markers, and the resulting clusters offered unique predictive power.

  13. Altered spontaneous brain activity pattern in patients with high myopia using amplitude of low-frequency fluctuation: a resting-state fMRI study

    Directory of Open Access Journals (Sweden)

    Huang X

    2016-11-01

    Full Text Available Xin Huang,1,2,* Fu-Qing Zhou,3,* Yu-Xiang Hu,1 Xiao-Xuan Xu,1 Xiong Zhou,4 Yu-Lin Zhong,1 Jun Wang,4 Xiao-Rong Wu1 1Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, 2Department of Ophthalmology, The First People’s Hospital of Jiujiang City, Jiujiang, 3Department of Radiology, The First Affiliated Hospital of Nanchang University, Jiangxi Province Medical Imaging Research Institute, 4Second Department of Respiratory Disease, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi, People’s Republic of China *These authors contributed equally to this work Objective: Many previous reports have demonstrated significant neural anatomy changes in the brain of high myopic (HM patients, whereas the spontaneous brain activity changes in the HM patients at rest are not well studied. Our objective was to use amplitude of low-frequency fluctuation (ALFF method to investigate the changes in spontaneous brain activity in HM patients and their relationships with clinical features. Methods: A total of 38 patients with HM (17 males and 21 females and 38 healthy controls (HCs (17 males and 21 females closely matched in age, sex, and education underwent resting-state functional magnetic resonance imaging scans. The ALFF method was used to assess local features of spontaneous brain activity. The relationship between the mean ALFF signal values in many brain regions and the clinical features in HM patients was calculated by correlation analysis. Results: Compared with HCs, the HM patients had significantly lower ALFF in the right inferior and middle temporal gyrus, left middle temporal gyrus, left inferior frontal gyrus/putamen, right inferior frontal gyrus/putamen/insula, right middle frontal gyrus, and right inferior parietal lobule and higher ALFF values in the bilateral midcingulate cortex, left postcentral gyrus, and left precuneus/inferior parietal lobule. However, no relationship was found between the mean ALFF

  14. Discovering anatomical patterns with pathological meaning by clustering of visual primitives in structural brain MRI

    Science.gov (United States)

    Leon, Juan; Pulido, Andrea; Romero, Eduardo

    2015-01-01

    Computational anatomy is a subdiscipline of the anatomy that studies macroscopic details of the human body structure using a set of automatic techniques. Different reference systems have been developed for brain mapping and morphometry in functional and structural studies. Several models integrate particular anatomical regions to highlight pathological patterns in structural brain MRI, a really challenging task due to the complexity, variability, and nonlinearity of the human brain anatomy. In this paper, we present a strategy that aims to find anatomical regions with pathological meaning by using a probabilistic analysis. Our method starts by extracting visual primitives from brain MRI that are partitioned into small patches and which are then softly clustered, forming different regions not necessarily connected. Each of these regions is described by a co- occurrence histogram of visual features, upon which a probabilistic semantic analysis is used to find the underlying structure of the information, i.e., separated regions by their low level similarity. The proposed approach was tested with the OASIS data set which includes 69 Alzheimer's disease (AD) patients and 65 healthy subjects (NC).

  15. Knowledge-guided robust MRI brain extraction for diverse large-scale neuroimaging studies on humans and non-human primates.

    Science.gov (United States)

    Wang, Yaping; Nie, Jingxin; Yap, Pew-Thian; Li, Gang; Shi, Feng; Geng, Xiujuan; Guo, Lei; Shen, Dinggang

    2014-01-01

    Accurate and robust brain extraction is a critical step in most neuroimaging analysis pipelines. In particular, for the large-scale multi-site neuroimaging studies involving a significant number of subjects with diverse age and diagnostic groups, accurate and robust extraction of the brain automatically and consistently is highly desirable. In this paper, we introduce population-specific probability maps to guide the brain extraction of diverse subject groups, including both healthy and diseased adult human populations, both developing and aging human populations, as well as non-human primates. Specifically, the proposed method combines an atlas-based approach, for coarse skull-stripping, with a deformable-surface-based approach that is guided by local intensity information and population-specific prior information learned from a set of real brain images for more localized refinement. Comprehensive quantitative evaluations were performed on the diverse large-scale populations of ADNI dataset with over 800 subjects (55 ∼ 90 years of age, multi-site, various diagnosis groups), OASIS dataset with over 400 subjects (18 ∼ 96 years of age, wide age range, various diagnosis groups), and NIH pediatrics dataset with 150 subjects (5 ∼ 18 years of age, multi-site, wide age range as a complementary age group to the adult dataset). The results demonstrate that our method consistently yields the best overall results across almost the entire human life span, with only a single set of parameters. To demonstrate its capability to work on non-human primates, the proposed method is further evaluated using a rhesus macaque dataset with 20 subjects. Quantitative comparisons with popularly used state-of-the-art methods, including BET, Two-pass BET, BET-B, BSE, HWA, ROBEX and AFNI, demonstrate that the proposed method performs favorably with superior performance on all testing datasets, indicating its robustness and effectiveness.

  16. Knowledge-guided robust MRI brain extraction for diverse large-scale neuroimaging studies on humans and non-human primates.

    Directory of Open Access Journals (Sweden)

    Yaping Wang

    Full Text Available Accurate and robust brain extraction is a critical step in most neuroimaging analysis pipelines. In particular, for the large-scale multi-site neuroimaging studies involving a significant number of subjects with diverse age and diagnostic groups, accurate and robust extraction of the brain automatically and consistently is highly desirable. In this paper, we introduce population-specific probability maps to guide the brain extraction of diverse subject groups, including both healthy and diseased adult human populations, both developing and aging human populations, as well as non-human primates. Specifically, the proposed method combines an atlas-based approach, for coarse skull-stripping, with a deformable-surface-based approach that is guided by local intensity information and population-specific prior information learned from a set of real brain images for more localized refinement. Comprehensive quantitative evaluations were performed on the diverse large-scale populations of ADNI dataset with over 800 subjects (55 ∼ 90 years of age, multi-site, various diagnosis groups, OASIS dataset with over 400 subjects (18 ∼ 96 years of age, wide age range, various diagnosis groups, and NIH pediatrics dataset with 150 subjects (5 ∼ 18 years of age, multi-site, wide age range as a complementary age group to the adult dataset. The results demonstrate that our method consistently yields the best overall results across almost the entire human life span, with only a single set of parameters. To demonstrate its capability to work on non-human primates, the proposed method is further evaluated using a rhesus macaque dataset with 20 subjects. Quantitative comparisons with popularly used state-of-the-art methods, including BET, Two-pass BET, BET-B, BSE, HWA, ROBEX and AFNI, demonstrate that the proposed method performs favorably with superior performance on all testing datasets, indicating its robustness and effectiveness.

  17. Conventional 3T brain MRI and diffusion tensor imaging in the diagnostic workup of early stage parkinsonism

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, Frederick J.A. [Radboud University Nijmegen Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Rumund, Anouke van; Tuladhar, Anil M.; Aerts, Marjolein B.; Titulaer, Imke; Esselink, Rianne A.J.; Bloem, Bastiaan R. [Radboud University Nijmegen Medical Center, Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Nijmegen (Netherlands); Verbeek, Marcel M. [Radboud University Nijmegen Medical Center, Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Nijmegen (Netherlands); Radboud University Nijmegen Medical Center, Department of Laboratory Medicine, Nijmegen (Netherlands); Goraj, Bozena [Radboud University Nijmegen Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Medical Center of Postgraduate Education, Department of Diagnostic Imaging, Warsaw (Poland)

    2015-07-15

    The aim of this study is to evaluate whether the diagnostic accuracy of 3 T brain MRI is improved by region of interest (ROI) measures of diffusion tensor imaging (DTI), to differentiate between neurodegenerative atypical parkinsonism (AP) and Parkinson's disease (PD) in early stage parkinsonism. We performed a prospective observational cohort study of 60 patients presenting with early stage parkinsonism and initial uncertain diagnosis. At baseline, patients underwent a 3 T brain MRI including DTI. After clinical follow-up (mean 28.3 months), diagnoses could be made in 49 patients (30 PD and 19 AP). Conventional brain MRI was evaluated for regions of atrophy and signal intensity changes. Tract-based spatial statistics and ROI analyses of DTI were performed to analyze group differences in mean diffusivity (MD) and fractional anisotropy (FA), and diagnostic thresholds were determined. Diagnostic accuracy of conventional brain MRI and DTI was assessed with the receiver operating characteristic (ROC). Significantly higher MD of the centrum semiovale, body corpus callosum, putamen, external capsule, midbrain, superior cerebellum, and superior cerebellar peduncles was found in AP. Significantly increased MD of the putamen was found in multiple system atrophy-parkinsonian form (MSA-P) and increased MD in the midbrain and superior cerebellar peduncles in progressive supranuclear palsy (PSP). The diagnostic accuracy of brain MRI to identify AP as a group was not improved by ROI measures of MD, though the diagnostic accuracy to identify MSA-P was slightly increased (AUC 0.82 to 0.85). The diagnostic accuracy of brain MRI to identify AP as a group was not improved by the current analysis approach to DTI, though DTI measures could be of added value to identify AP subgroups. (orig.)

  18. Pediatric MRI

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIH Study of Normal Brain Development is a longitudinal study using anatomical MRI, diffusion tensor imaging (DTI), and MR spectroscopy (MRS) to map pediatric...

  19. Accuracy of UTE-MRI-based patient setup for brain cancer radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yingli; Cao, Minsong; Kaprealian, Tania; Sheng, Ke; Gao, Yu; Gomez, Caitlin; Santhanam, Anand; Tenn, Stephen; Agazaryan, Nzhde; Low, Daniel A. [Department of Radiation Oncology, University of California, Los Angeles, California 90095 (United States); Han, Fei; Hu, Peng, E-mail: penghu@mednet.ucla.edu [Department of Radiological Sciences, University of California, Los Angeles, California 90095 (United States)

    2016-01-15

    Purpose: Radiation therapy simulations solely based on MRI have advantages compared to CT-based approaches. One feature readily available from computed tomography (CT) that would need to be reproduced with MR is the ability to compute digitally reconstructed radiographs (DRRs) for comparison against on-board radiographs commonly used for patient positioning. In this study, the authors generate MR-based bone images using a single ultrashort echo time (UTE) pulse sequence and quantify their 3D and 2D image registration accuracy to CT and radiographic images for treatments in the cranium. Methods: Seven brain cancer patients were scanned at 1.5 T using a radial UTE sequence. The sequence acquired two images at two different echo times. The two images were processed using an in-house software to generate the UTE bone images. The resultant bone images were rigidly registered to simulation CT data and the registration error was determined using manually annotated landmarks as references. DRRs were created based on UTE-MRI and registered to simulated on-board images (OBIs) and actual clinical 2D oblique images from ExacTrac™. Results: UTE-MRI resulted in well visualized cranial, facial, and vertebral bones that quantitatively matched the bones in the CT images with geometric measurement errors of less than 1 mm. The registration error between DRRs generated from 3D UTE-MRI and the simulated 2D OBIs or the clinical oblique x-ray images was also less than 1 mm for all patients. Conclusions: UTE-MRI-based DRRs appear to be promising for daily patient setup of brain cancer radiotherapy with kV on-board imaging.

  20. Quantitative estimation of brain atrophy and function with PET and MRI two-dimensional projection images

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Reiko; Uemura, Koji; Uchiyama, Akihiko [Waseda Univ., Tokyo (Japan). School of Science and Engineering; Toyama, Hinako; Ishii, Kenji; Senda, Michio

    2001-05-01

    The purpose of this paper is to estimate the extent of atrophy and the decline in brain function objectively and quantitatively. Two-dimensional (2D) projection images of three-dimensional (3D) transaxial images of positron emission tomography (PET) and magnetic resonance imaging (MRI) were made by means of the Mollweide method which keeps the area of the brain surface. A correlation image was generated between 2D projection images of MRI and cerebral blood flow (CBF) or {sup 18}F-fluorodeoxyglucose (FDG) PET images and the sulcus was extracted from the correlation image clustered by K-means method. Furthermore, the extent of atrophy was evaluated from the extracted sulcus on 2D-projection MRI and the cerebral cortical function such as blood flow or glucose metabolic rate was assessed in the cortex excluding sulcus on 2D-projection PET image, and then the relationship between the cerebral atrophy and function was evaluated. This method was applied to the two groups, the young and the aged normal subjects, and the relationship between the age and the rate of atrophy or the cerebral blood flow was investigated. This method was also applied to FDG-PET and MRI studies in the normal controls and in patients with corticobasal degeneration. The mean rate of atrophy in the aged group was found to be higher than that in the young. The mean value and the variance of the cerebral blood flow for the young are greater than those of the aged. The sulci were similarly extracted using either CBF or FDG PET images. The purposed method using 2-D projection images of MRI and PET is clinically useful for quantitative assessment of atrophic change and functional disorder of cerebral cortex. (author)

  1. Epileptic networks studied with EEG-fMRI.

    Science.gov (United States)

    Gotman, Jean

    2008-01-01

    It is not easy to determine the location of the cerebral generators and the other brain regions that may be involved at the time of an epileptic spike seen in the scalp EEG. The possibility to combine EEG recording with functional MRI scanning (fMRI) opens the opportunity to uncover the regions of the brain showing changes in metabolism and blood flow in response to epileptic spikes seen in the EEG. These regions are presumably involved in the abnormal neuronal activity at the origin of epileptic discharges. This paper reviews the methodology involved in performing such studies, including the special techniques required for recording the EEG inside the scanner and the statistical issues in analyzing the fMRI signal. We then discuss the results obtained in patients with different types of focal epileptic disorders and in patients with primary generalized epilepsy. The results in general indicate that interictal epileptic discharges may affect brain areas well beyond the presumed region in which they are generated. The noninvasive nature of this method opens new horizons in the investigation of brain regions involved and affected by epileptic discharges.

  2. Susceptibility Contrast in High Field MRI of Human Brain as a Function of Tissue Iron Content

    Science.gov (United States)

    Yao, Bing; Li, Tie-Qiang; van Gelderen, Peter; Shmueli, Karin; de Zwart, Jacco A.; Duyn, Jeff H.

    2009-01-01

    Magnetic susceptibility provides an important contrast mechanism for MRI. Increasingly, susceptibility-based contrast is being exploited to investigate brain tissue microstructure and to detect abnormal levels of brain iron as these have been implicated in a variety of neuro-degenerative diseases. However, it remains unclear to what extent magnetic susceptibility-related contrast at high field relates to actual brain iron concentrations. In this study, we performed susceptibility weighted imaging as a function of field strength on healthy brains in vivo and post-mortem brain tissues at 1.5T, 3T and 7T. Iron histology was performed on the tissue samples for comparison. The calculated susceptibility-related parameters R2* and signal frequency shift in four iron-rich regions (putamen, globus pallidus, caudate, and thalamus) showed an almost linear dependence (r=0.90 for R2*; r=0.83 for phase, p<0.01) on field strength, suggesting that potential ferritin saturation effects are not relevant to susceptibility-weighted contrast for field strengths up to 7T. The R2* dependence on the putative (literature-based) iron concentration was 0.048 Hz/Tesla/ppm. The histological data from brain samples confirmed the linear dependence of R2* on field strength and showed a slope against iron concentration of 0.0099 Hz/Tesla/ppm dry-weight, which is equivalent to 0.05 Hz/Tesla/ppm wet-weight and closely matched the calculated value in vivo. These results confirm the validity of using susceptibility-weighted contrast as an indicator of iron content in iron-rich brain regions. The absence of saturation effects opens the way to exploit the benefits of MRI at high field strengths for the detection of iron distributions with high sensitivity and resolution. PMID:19027861

  3. Association of Coffee Consumption with MRI Markers and Cognitive Function: A Population-Based Study

    OpenAIRE

    Araújo, Larissa Fortunato; Mirza, Saira; Bos, Daniel; Niessen, Wiro; Barreto, Sandhi Maria; Van der Lugt, Aad; Vernooij, Meike; Hofman, Albert; Tiemeier, Henning; Ikram, Arfan,; Polidori, M. C.

    2016-01-01

    textabstractBackground: Coffee is one of the most widely consumed beverages worldwide and has been of considerable interest in research on cognition and dementia. Objective: To investigate the effect of coffee on preclinical brain MRI markers of dementia and cognitive performance. Methods: In 2,914 participants from the population-based Rotterdam Study (mean age: 59.3±7.2 years, 55 females), we assessed coffee consumption, performed brain MRI, and assessed cognition at baseline. To study cogn...

  4. A Feasibility Study of Quantifying Longitudinal Brain Changes in Herpes Simplex Virus (HSV) Encephalitis Using Magnetic Resonance Imaging (MRI) and Stereology

    Science.gov (United States)

    Keller, Simon S.; Das, Kumar; Vidyasagar, Rishma; Parkes, Laura M.; Burnside, Girvan; Griffiths, Michael; Kopelman, Michael; Roberts, Neil; Solomon, Tom

    2017-01-01

    Objectives To assess whether it is feasible to quantify acute change in temporal lobe volume and total oedema volumes in herpes simplex virus (HSV) encephalitis as a preliminary to a trial of corticosteroid therapy. Methods The study analysed serially acquired magnetic resonance images (MRI), of patients with acute HSV encephalitis who had neuroimaging repeated within four weeks of the first scan. We performed volumetric measurements of the left and right temporal lobes and of cerebral oedema visible on T2 weighted Fluid Attenuated Inversion Recovery (FLAIR) images using stereology in conjunction with point counting. Results Temporal lobe volumes increased on average by 1.6% (standard deviation (SD 11%) in five patients who had not received corticosteroid therapy and decreased in two patients who had received corticosteroids by 8.5%. FLAIR hyperintensity volumes increased by 9% in patients not receiving treatment with corticosteroids and decreased by 29% in the two patients that had received corticosteroids. Conclusions This study has shown it is feasible to quantify acute change in temporal lobe and total oedema volumes in HSV encephalitis and suggests a potential resolution of swelling in response to corticosteroid therapy. These techniques could be used as part of a randomized control trial to investigate the efficacy of corticosteroids for treating HSV encephalitis in conjunction with assessing clinical outcomes and could be of potential value in helping to predict the clinical outcomes of patients with HSV encephalitis. PMID:28125598

  5. Individualized prediction of illness course at the first psychotic episode: a support vector machine MRI study.

    LENUS (Irish Health Repository)

    Mourao-Miranda, J

    2012-05-01

    To date, magnetic resonance imaging (MRI) has made little impact on the diagnosis and monitoring of psychoses in individual patients. In this study, we used a support vector machine (SVM) whole-brain classification approach to predict future illness course at the individual level from MRI data obtained at the first psychotic episode.

  6. Intrinsic brain network abnormalities in migraines without aura revealed in resting-state fMRI.

    Directory of Open Access Journals (Sweden)

    Ting Xue

    Full Text Available BACKGROUND: Previous studies have defined low-frequency, spatially consistent intrinsic connectivity networks (ICN in resting functional magnetic resonance imaging (fMRI data which reflect functional interactions among distinct brain areas. We sought to explore whether and how repeated migraine attacks influence intrinsic brain connectivity, as well as how activity in these networks correlates with clinical indicators of migraine. METHODS/PRINCIPAL FINDINGS: Resting-state fMRI data in twenty-three patients with migraines without aura (MwoA and 23 age- and gender-matched healthy controls (HC were analyzed using independent component analysis (ICA, in combination with a "dual-regression" technique to identify the group differences of three important pain-related networks [default mode network (DMN, bilateral central executive network (CEN, salience network (SN] between the MwoA patients and HC. Compared with the HC, MwoA patients showed aberrant intrinsic connectivity within the bilateral CEN and SN, and greater connectivity between both the DMN and right CEN (rCEN and the insula cortex - a critical region involving in pain processing. Furthermore, greater connectivity between both the DMN and rCEN and the insula correlated with duration of migraine. CONCLUSIONS: Our findings may provide new insights into the characterization of migraine as a condition affecting brain activity in intrinsic connectivity networks. Moreover, the abnormalities may be the consequence of a persistent central neural system dysfunction, reflecting cumulative brain insults due to frequent ongoing migraine attacks.

  7. Localisation of the brain in fetal MRI using bundled SIFT features.

    Science.gov (United States)

    Keraudren, Kevin; Kyriakopoulou, Vanessa; Rutherford, Mary; Hajnal, Joseph V; Rueckert, Daniel

    2013-01-01

    Fetal MRI is a rapidly emerging diagnostic imaging tool. Its main focus is currently on brain imaging, but there is a huge potential for whole body studies. We propose a method for accurate and robust localisation of the fetal brain in MRI when the image data is acquired as a stack of 2D slices misaligned due to fetal motion. We first detect possible brain locations in 2D images with a Bag-of-Words model using SIFT features aggregated within Maximally Stable Extremal Regions (called bundled SIFT), followed by a robust fitting of an axis-aligned 3D box to the selected regions. We rely on prior knowledge of the fetal brain development to define size and shape constraints. In a cross-validation experiment, we obtained a median error distance of 5.7mm from the ground truth and no missed detection on a database of 59 fetuses. This 2D approach thus allows a robust detection even in the presence of substantial fetal motion.

  8. Endoscopy-verified occult subependymal dissemination of glioblastoma and brain metastasis undetected by MRI: prognostic significance

    Science.gov (United States)

    Iacoangeli, Maurizio; Di Rienzo, Alessandro; Colasanti, Roberto; Zizzi, Antonio; Gladi, Maurizio; Alvaro, Lorenzo; Nocchi, Niccolò; Di Somma, Lucia Giovanna Maria; Scarpelli, Marina; Scerrati, Massimo

    2012-01-01

    Although various prognostic indices exist for patients with malignant brain tumors, the prognostic significance of the subependymal spread of intracranial tumors is still a matter of debate. In this paper, we report the cases of two intraventricular lesions, a recurrent glioblastoma multiforme (GBM) and a brain metastasis, each successfully treated with a neuroendoscopic approach. Thanks to this minimally invasive approach, we achieved good therapeutic results: we obtained a histological diagnosis; we controlled intracranial hypertension by treating the associated hydrocephalus and, above all, compared with a microsurgical approach, we reduced the risks related to dissection and brain retraction. Moreover, in both cases, neuroendoscopy enabled us to identify an initial, precocious subependymal tumor spreading below the threshold of magnetic resonance imaging (MRI) detection. This finding, undetected in pre-operative MRI scans, was then evident during follow-up neuroimaging studies. In light of these data, a neuroendoscopic approach might play a leading role in better defining the prognosis and optimally tailored management protocols for GBM and brain metastasis. PMID:23271915

  9. A three-dimensional MRI atlas of the zebra finch brain in stereotaxic coordinates

    DEFF Research Database (Denmark)

    Poirier, Colline; Vellema, Michiel; Verhoye, Marleen;

    2008-01-01

    of different brain areas (nuclei) involved in the sensory and motor control of song. Until now, the only published atlases of songbird brains consisted in drawings based on histological slices of the canary and of the zebra finch brain. Taking advantage of high-magnetic field (7 Tesla) MRI technique, we...

  10. Multivariate imaging-genetics study of MRI gray matter volume and SNPs reveals biological pathways correlated with brain structural differences in Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Sabin Khadka

    2016-07-01

    Full Text Available Background: Attention Deficit Hyperactivity Disorder (ADHD is a prevalent neurodevelopmental disorder affecting children, adolescents, and adults. Its etiology is not well-understood, but it is increasingly believed to result from diverse pathophysiologies that affect the structure and function of specific brain circuits. Although one of the best-studied neurobiological abnormalities in ADHD is reduced fronto-striatal-cerebellar gray matter volume, its specific genetic correlates are largely unknown. Methods: In this study, T1-weighted MR images of brain structure were collected from 198 adolescents (63 ADHD-diagnosed. A multivariate parallel independent component analysis technique (Para-ICA identified imaging-genetic relationships between regional gray matter volume and single nucleotide polymorphism data. Results: Para-ICA analyses extracted 14 components from genetic data and 9 from MR data. An iterative cross-validation using randomly-chosen sub-samples indicated acceptable stability of these ICA solutions. A series of partial correlation analyses controlling for age, sex, and ethnicity revealed two genotype-phenotype component pairs significantly differed between ADHD and non-ADHD groups, after a Bonferroni correction for multiple comparisons. The brain phenotype component not only included structures frequently found to have abnormally low volume in previous ADHD studies, but was also significantly associated with ADHD differences in symptom severity and performance on cognitive tests frequently found to be impaired in patients diagnosed with the disorder. Pathway analysis of the genotype component identified several different biological pathways linked to these structural abnormalities in ADHD. Conclusions: Some of these pathways implicate well-known dopaminergic neurotransmission and neurodevelopment hypothesized to be abnormal in ADHD. Other more recently implicated pathways included glutamatergic and GABA-eric physiological systems

  11. Unidentified bright objects on brain MRI in children as a diagnostic criterion for neurofibromatosis type 1

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Ferraz Filho, Jose R.; Pontes Munis, Marcos; Soares Souza, Antonio; Sanches, Rafael A. [Medical School in Sao Jose do Rio Preto, Imaging Department, Sao Jose do Rio Preto, Sao Paulo (Brazil); Goloni-Bertollo, Eni M.; Pavarino-Bertelli, Erika C. [Center of Research and Attendance in Neurofibromatosis, Sao Paulo (Brazil)

    2008-03-15

    Lesions of the brain denominated as unidentified bright objects (UBOs), which are not included in the diagnostic criteria for neurofibromatosis type 1 (NF1) established by the National Institutes of Health (NIH), have been detected by MRI. The purpose of this study was to investigate the possibility of including the presence of UBOs as a diagnostic criterion for NF1 in children. The study included 88 children between the ages of 2 and 18 years. The case group consisted of 40 children diagnosed with sporadic or familial NF1 according to the criteria established by the NIH. A control group consisted of 48 individuals referred for routine MRI of the brain for other complaints not related to NF1. UBOs were identified in 70% of the NF1 patients and in none of the control group. The sensitivity of the presence of UBOs for the diagnosis of NF1 was 70% (CI 53-83%), with a false-negative rate of 30% (CI 27-47%), a specificity of 100% (CI 86-100%) and a false-positive rate of 0% (CI 0-14%). Faced with the difficulties in diagnosing NF1 in children and the high frequency and specificity of the presence UBOs identified by MRI in our series, we recommend the inclusion of the presence UBOs as a diagnostic criterion for NF1 in children. (orig.)

  12. MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain

    OpenAIRE

    2015-01-01

    Recently, the “glymphatic system” of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol,...

  13. Tracing Activity across the Whole Brain Neural Network with Optogenetic Functional Magnetic Resonance Imaging (ofMRI

    Directory of Open Access Journals (Sweden)

    Jin Hyung eLee

    2011-10-01

    Full Text Available Despite the overwhelming need, there has been a relatively large gap in our ability to trace network level activity across the brain. The complex dense wiring of the brain makes it extremely challenging to understand a specific set of neuron’s activity and their communication beyond a few synapses. Recent development of the optogenetic functional magnetic resonance imaging (ofMRI provides a new impetus for the study of the brain circuit by enabling causal tracing of the brain circuit activity across the whole brain. Brain circuit elements can be selectively triggered based on their genetic identity, cell body location, and/or their axonal projection target with temporal precision while the resulting network response is monitored non-invasively with unprecedented spatial and temporal accuracy. With further studies including technological innovations to bring ofMRI to its full potential, ofMRI is expected to play an important role in our system-level understanding of the brain circuit mechanism.

  14. FULLY AUTOMATIC FRAMEWORK FOR SEGMENTATION OF BRAIN MRI IMAGE

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Automaticbraintissuesegmentationfrommag neticresonanceimages(MRI)isofgreatimportance forresearchandclinicalstudyofmuchneurological pathology.Duringthepastdecade,theMRIhashad agreatimpactonthediagnosticimagingofmosthu manorgansystem.ThesegmentationofbrainMRI imagesplaysanimportantroleinthevolumerecon structionforavarietyofmedicalimageanalysis, computer aideddiagnosis,three dimensionalrecon structionandvisualizationapplications.Theaccu rateSegmentationofMRimagesintodifferenttis sueclasses,especiallygray...

  15. Growth trajectories of the human fetal brain tissues estimated from 3D reconstructed in utero MRI.

    Science.gov (United States)

    Scott, Julia A; Habas, Piotr A; Kim, Kio; Rajagopalan, Vidya; Hamzelou, Kia S; Corbett-Detig, James M; Barkovich, A James; Glenn, Orit A; Studholme, Colin

    2011-08-01

    In the latter half of gestation (20-40 gestational weeks), human brain growth accelerates in conjunction with cortical folding and the deceleration of ventricular zone progenitor cell proliferation. These processes are reflected in changes in the volume of respective fetal tissue zones. Thus far, growth trajectories of the fetal tissue zones have been extracted primarily from 2D measurements on histological sections and magnetic resonance imaging (MRI). In this study, the volumes of major fetal zones-cortical plate (CP), subplate and intermediate zone (SP+IZ), germinal matrix (GMAT), deep gray nuclei (DG), and ventricles (VENT)--are calculated from automatic segmentation of motion-corrected, 3D reconstructed MRI. We analyzed 48 T2-weighted MRI scans from 39 normally developing fetuses in utero between 20.57 and 31.14 gestational weeks (GW). The supratentorial volume (STV) increased linearly at a rate of 15.22% per week. The SP+IZ (14.75% per week) and DG (15.56% per week) volumes increased at similar rates. The CP increased at a greater relative rate (18.00% per week), while the VENT (9.18% per week) changed more slowly. Therefore, CP increased as a fraction of STV and the VENT fraction declined. The total GMAT volume slightly increased then decreased after 25 GW. We did not detect volumetric sexual dimorphisms or total hemispheric volume asymmetries, which may emerge later in gestation. Further application of the automated fetal brain segmentation to later gestational ages will bridge the gap between volumetric studies of premature brain development and normal brain development in utero.

  16. Joint EEG/fMRI state space model for the detection of directed interactions in human brains--a simulation study

    NARCIS (Netherlands)

    Lenz, Michael; Musso, Mariachristina; Linke, Yannick; Tüscher, Oliver; Timmer, Jens; Weiller, Cornelius; Schelter, Björn

    2011-01-01

    An often addressed challenge in neuroscience research is the assignment of different tasks to specific brain regions. In many cases several brain regions are activated during a single task. Therefore, one is also interested in the temporal evolution of brain activity to infer causal relations betwee

  17. Segmentation of MRI Brain Images with an Improved Harmony Searching Algorithm.

    Science.gov (United States)

    Yang, Zhang; Shufan, Ye; Li, Guo; Weifeng, Ding

    2016-01-01

    The harmony searching (HS) algorithm is a kind of optimization search algorithm currently applied in many practical problems. The HS algorithm constantly revises variables in the harmony database and the probability of different values that can be used to complete iteration convergence to achieve the optimal effect. Accordingly, this study proposed a modified algorithm to improve the efficiency of the algorithm. First, a rough set algorithm was employed to improve the convergence and accuracy of the HS algorithm. Then, the optimal value was obtained using the improved HS algorithm. The optimal value of convergence was employed as the initial value of the fuzzy clustering algorithm for segmenting magnetic resonance imaging (MRI) brain images. Experimental results showed that the improved HS algorithm attained better convergence and more accurate results than those of the original HS algorithm. In our study, the MRI image segmentation effect of the improved algorithm was superior to that of the original fuzzy clustering method.

  18. Comparison between MRI-based attenuation correction methods for brain PET in dementia patients

    Energy Technology Data Exchange (ETDEWEB)

    Cabello, Jorge; Lukas, Mathias; Pyka, Thomas; Nekolla, Stephan G.; Ziegler, Sibylle I. [Technische Universitaet Muenchen, Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Munich (Germany); Rota Kops, Elena; Shah, N. Jon [Forschungszentrum Juelich GmbH, Institute of Neuroscience and Medicine 4, Medical Imaging Physics, Juelich (Germany); Ribeiro, Andre [Forschungszentrum Juelich GmbH, Institute of Neuroscience and Medicine 4, Medical Imaging Physics, Juelich (Germany); Institute of Biophysics and Biomedical Engineering, Lisbon (Portugal); Yakushev, Igor [Technische Universitaet Muenchen, Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Munich (Germany); Institute TUM Neuroimaging Center (TUM-NIC), Munich (Germany)

    2016-11-15

    The combination of Positron Emission Tomography (PET) with magnetic resonance imaging (MRI) in hybrid PET/MRI scanners offers a number of advantages in investigating brain structure and function. A critical step of PET data reconstruction is attenuation correction (AC). Accounting for bone in attenuation maps (μ-map) was shown to be important in brain PET studies. While there are a number of MRI-based AC methods, no systematic comparison between them has been performed so far. The aim of this work was to study the different performance obtained by some of the recent methods presented in the literature. To perform such a comparison, we focused on [{sup 18}F]-Fluorodeoxyglucose-PET/MRI neurodegenerative dementing disorders, which are known to exhibit reduced levels of glucose metabolism in certain brain regions. Four novel methods were used to calculate μ-maps from MRI data of 15 patients with Alzheimer's dementia (AD). The methods cover two atlas-based methods, a segmentation method, and a hybrid template/segmentation method. Additionally, the Dixon-based and a UTE-based method, offered by a vendor, were included in the comparison. Performance was assessed at three levels: tissue identification accuracy in the μ-map, quantitative accuracy of reconstructed PET data in specific brain regions, and precision in diagnostic images at identifying hypometabolic areas. Quantitative regional errors of -20-10 % were obtained using the vendor's AC methods, whereas the novel methods produced errors in a margin of ±5 %. The obtained precision at identifying areas with abnormally low levels of glucose uptake, potentially regions affected by AD, were 62.9 and 79.5 % for the two vendor AC methods, the former ignoring bone and the latter including bone information. The precision increased to 87.5-93.3 % in average for the four new methods, exhibiting similar performances. We confirm that the AC methods based on the Dixon and UTE sequences provided by the vendor are

  19. High spatial resolution brain functional MRI using submillimeter balanced steady-state free precession acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Pei-Hsin; Chung, Hsiao-Wen [Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Tsai, Ping-Huei [Imaging Research Center, Taipei Medical University, Taipei 11031, Taiwan and Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei 11031, Taiwan (China); Wu, Ming-Long, E-mail: minglong.wu@csie.ncku.edu.tw [Institute of Medical Informatics, National Cheng-Kung University, Tainan 70101, Taiwan and Department of Computer Science and Information Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China); Chuang, Tzu-Chao [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Shih, Yi-Yu [Siemens Limited Healthcare Sector, Taipei 11503, Taiwan (China); Huang, Teng-Yi [Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China)

    2013-12-15

    Purpose: One of the technical advantages of functional magnetic resonance imaging (fMRI) is its precise localization of changes from neuronal activities. While current practice of fMRI acquisition at voxel size around 3 × 3 × 3 mm{sup 3} achieves satisfactory results in studies of basic brain functions, higher spatial resolution is required in order to resolve finer cortical structures. This study investigated spatial resolution effects on brain fMRI experiments using balanced steady-state free precession (bSSFP) imaging with 0.37 mm{sup 3} voxel volume at 3.0 T. Methods: In fMRI experiments, full and unilateral visual field 5 Hz flashing checkerboard stimulations were given to healthy subjects. The bSSFP imaging experiments were performed at three different frequency offsets to widen the coverage, with functional activations in the primary visual cortex analyzed using the general linear model. Variations of the spatial resolution were achieved by removing outerk-space data components. Results: Results show that a reduction in voxel volume from 3.44 × 3.44 × 2 mm{sup 3} to 0.43 × 0.43 × 2 mm{sup 3} has resulted in an increase of the functional activation signals from (7.7 ± 1.7)% to (20.9 ± 2.0)% at 3.0 T, despite of the threefold SNR decreases in the original images, leading to nearly invariant functional contrast-to-noise ratios (fCNR) even at high spatial resolution. Activation signals aligning nicely with gray matter sulci at high spatial resolution would, on the other hand, have possibly been mistaken as noise at low spatial resolution. Conclusions: It is concluded that the bSSFP sequence is a plausible technique for fMRI investigations at submillimeter voxel widths without compromising fCNR. The reduction of partial volume averaging with nonactivated brain tissues to retain fCNR is uniquely suitable for high spatial resolution applications such as the resolving of columnar organization in the brain.

  20. Evaluation of electrode position in deep brain stimulation by image fusion (MRI and CT)

    Energy Technology Data Exchange (ETDEWEB)

    Barnaure, I.; Lovblad, K.O.; Vargas, M.I. [Geneva University Hospital, Department of Neuroradiology, Geneva 14 (Switzerland); Pollak, P.; Horvath, J.; Boex, C.; Burkhard, P. [Geneva University Hospital, Department of Neurology, Geneva (Switzerland); Momjian, S. [Geneva University Hospital, Department of Neurosurgery, Geneva (Switzerland); Remuinan, J. [Geneva University Hospital, Department of Radiology, Geneva (Switzerland)

    2015-09-15

    Imaging has an essential role in the evaluation of correct positioning of electrodes implanted for deep brain stimulation (DBS). Although MRI offers superior anatomic visualization of target sites, there are safety concerns in patients with implanted material; imaging guidelines are inconsistent and vary. The fusion of postoperative CT with preoperative MRI images can be an alternative for the assessment of electrode positioning. The purpose of this study was to assess the accuracy of measurements realized on fused images (acquired without a stereotactic frame) using a manufacturer-provided software. Data from 23 Parkinson's disease patients who underwent bilateral electrode placement for subthalamic nucleus (STN) DBS were acquired. Preoperative high-resolution T2-weighted sequences at 3 T, and postoperative CT series were fused using a commercially available software. Electrode tip position was measured on the obtained images in three directions (in relation to the midline, the AC-PC line and an AC-PC line orthogonal, respectively) and assessed in relation to measures realized on postoperative 3D T1 images acquired at 1.5 T. Mean differences between measures carried out on fused images and on postoperative MRI lay between 0.17 and 0.97 mm. Fusion of CT and MRI images provides a safe and fast technique for postoperative assessment of electrode position in DBS. (orig.)

  1. Connectivity in Autism: A review of MRI connectivity studies

    Science.gov (United States)

    Rane, Pallavi; Cochran, David; Hodge, Steven M.; Haselgrove, Christian; Kennedy, David; Frazier, Jean A.

    2016-01-01

    Autism Spectrum Disorder (ASD) affects 1 in 50 children between the ages of 6–17 years as per a 2012 CDC survey of parents. The etiology of ASD is not precisely known. ASD is an umbrella term, which includes low (IQ70) individuals. A better understanding of the disorder, and how it manifests in an individual subject can lead to more effective intervention plans to fulfill the individual’s treatment needs. Magnetic resonance imaging (MRI) is a non-invasive investigational tool that can help study the ways in which the brain develops and/or deviates from the typical developmental trajectory. MRI offers insights into the structure, function, and metabolism of the brain. In this article, we review published studies on brain connectivity changes in ASD using either resting state functional MRI or diffusion tensor imaging. The general findings of decreases in white matter integrity and long-range neural coherence are prevalent in ASD literature. However, there is somewhat less of a consensus in the detailed localization of these findings. There are even fewer studies linking these connectivity alterations with the behavioral phenotype of the disorder. Nevertheless, with the help of data sharing and large-scale analytic efforts, the field is advancing towards several convergent themes. These include reduced functional coherence of long-range intra-hemispheric cortico-cortical default mode circuitry, impaired inter-hemispheric regulation, and an associated, perhaps compensatory, increase in local and short-range cortico-subcortical coherence. PMID:26146755

  2. Correlation between MRI findings and long-term outcome in patients with severe brain trauma

    Energy Technology Data Exchange (ETDEWEB)

    Pierallini, A.; Pantano, P.; Fantozzi, L.M.; Bonamini, M. [Dept. of Neurological Sciences, Univ. di Roma (Italy); Vichi, R.; Zylberman, R.; Pisarri, F. [Hospital San Giovanni Battista, SMOM, Roma (Italy); Colonnese, C. [IRCCS Neuromed, Pozzilli (Italy); Bozzao, L. [Dept. of Neurological Sciences, Univ. di Roma (Italy); IRCCS Neuromed, Pozzilli (Italy)

    2000-12-01

    Our aim was to relate MRI findings in patients with severe traumatic brain injury (TBI) to clinical severity and long-term outcome. We studied 37 patients with severe TBI, who were submitted to clinical assessment for disability and cognition and to MRI 60-90 days after trauma. Clinical assessment was also performed 3, 6 and 12 months later. The number and volume of lesions in various cerebral structures were calculated semiautomatically from FLAIR and fast field-echo images. Possible correlations between total and regional lesion volume and clinical deficits were then investigated. The frontal and temporal lobes were most frequently involved. Total lesion volume on FLAIR images correlated significantly with clinical outcome, whereas that on FFE images did not. Regional analysis showed that FLAIR lesion volume in the corpus callosum correlated significantly with scores on disability and cognition scales at the first clinical assessment. FLAIR lesion volume in the frontal lobes correlated significantly with clinical scores 1 year later. (orig.)

  3. fMRI mapping of the visual system in the mouse brain with interleaved snapshot GE-EPI.

    Science.gov (United States)

    Niranjan, Arun; Christie, Isabel N; Solomon, Samuel G; Wells, Jack A; Lythgoe, Mark F

    2016-06-10

    The use of functional magnetic resonance imaging (fMRI) in mice is increasingly prevalent, providing a means to non-invasively characterise functional abnormalities associated with genetic models of human diseases. The predominant stimulus used in task-based fMRI in the mouse is electrical stimulation of the paw. Task-based fMRI in mice using visual stimuli remains underexplored, despite visual stimuli being common in human fMRI studies. In this study, we map the mouse brain visual system with BOLD measurements at 9.4T using flashing light stimuli with medetomidine anaesthesia. BOLD responses were observed in the lateral geniculate nucleus, the superior colliculus and the primary visual area of the cortex, and were modulated by the flashing frequency, diffuse vs focussed light and stimulus context. Negative BOLD responses were measured in the visual cortex at 10Hz flashing frequency; but turned positive below 5Hz. In addition, the use of interleaved snapshot GE-EPI improved fMRI image quality without diminishing the temporal contrast-noise-ratio. Taken together, this work demonstrates a novel methodological protocol in which the mouse brain visual system can be non-invasively investigated using BOLD fMRI.

  4. AN ARTIFICIAL FISH SWARM OPTIMIZED FUZZY MRI IMAGE SEGMENTATION APPROACH FOR IMPROVING IDENTIFICATION OF BRAIN TUMOUR

    OpenAIRE

    Jagadeesan, R; S.N. Sivanandam

    2013-01-01

    In image processing, it is difficult to detect the abnormalities in brain especially in MRI brain images. Also the tumor segmentation from MRI image data is an important; however it is time consumingwhile carried out by medical specialists. A lot of methods have been proposed to solve MR images problems, quite difficult to develop an automated recognition system which could process on a large information of patient and provide a correct estimation. Hence enhanced k-means and fuzzy c-means wit...

  5. 第二外语读音处理时脑活动差异的功能性磁共振成像研究%Different Brain Activation of Second Language Phonological Processing:an fMRI Study

    Institute of Scientific and Technical Information of China (English)

    李修军; 郭启勇; 吴景龙

    2014-01-01

    We studied that the bilingual subjects in Chinese and Japanese phonological judgment brain activity difference problem and we found that the difference brain regions in Chinese-Japanese bilingual. We used Chinese-Japanese bilin-gual subjects,using Chinese phonological judgment and Japanese phonological judgment tasks implemented in the study of functional magnetic resonance imaging. Using functional magnetic resonance imaging (fMRI) is different in judging the Japanese phonological and Chinese phonological tasks in brain activation,and the results of second language phono-logical processing different brain regions. The results showed that Chinese-Japanese bilingual subjects between Japanese phonological and Chinese phonological processing differences brain activities,mainly brain areas include:the right frontal gyrus (BA44/45),right temporal lobe (BA7/40),the left fusiform gyrus (BA37).%实验针对双语被试在进行中文和日语读音判断任务时脑活动差异的问题展开研究,发现了二者差异性脑区。利用中-日双语被试,使用中文读音判断和日文读音判断两种实验任务,实施了功能性磁共振研究。通过功能性磁共振成像(fMRI)技术,比较被试在判断日文读音和中文读音任务中不同的脑激活情况,进而得到第二外语读音处理的差异性脑区。结果表明中-日双语被试在进行日语读音处理和中文读音处理时脑活动之间存在差异,主要集中在以下脑区:右侧额叶下回(BA44/45),右侧颞叶(BA7/40),左侧纺锤状回(BA37)。

  6. Seizure-induced brain lesions: A wide spectrum of variably reversible MRI abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Cianfoni, A., E-mail: acianfoni@hotmail.com [Neuroradiology, Neurocenter of Italian Switzerland–Ospedale regionale Lugano, Via Tesserete 46, Lugano, 6900, CH (Switzerland); Caulo, M., E-mail: caulo@unich.it [Department of Neuroscience and Imaging, University of Chieti, Via dei Vestini 33, 6610 Chieti. Italy (Italy); Cerase, A., E-mail: alfonsocerase@gmail.com [Unit of Neuroimaging and Neurointervention NINT, Department of Neurological and Sensorineural Sciences, Azienda Ospedaliera Universitaria Senese, Policlinico “Santa Maria alle Scotte”, V.le Bracci 16, Siena (Italy); Della Marca, G., E-mail: dellamarca@rm.unicatt.it [Neurology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Falcone, C., E-mail: carlo_falc@libero.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Di Lella, G.M., E-mail: gdilella@rm.unicatt.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Gaudino, S., E-mail: sgaudino@sirm.org [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy); Edwards, J., E-mail: edwardjc@musc.edu [Neuroscience Dept., Medical University of South Carolina, 96J Lucas st, 29425, Charleston, SC (United States); Colosimo, C., E-mail: colosimo@rm.unicatt.it [Radiology Dept., Catholic University of Rome, L.go F Vito 1, 00100, Rome (Italy)

    2013-11-01

    Introduction MRI abnormalities in the postictal period might represent the effect of the seizure activity, rather than its structural cause. Material and Methods Retrospective review of clinical and neuroimaging charts of 26 patients diagnosed with seizure-related MR-signal changes. All patients underwent brain-MRI (1.5-Tesla, standard pre- and post-contrast brain imaging, including DWI-ADC in 19/26) within 7 days from a seizure and at least one follow-up MRI, showing partial or complete reversibility of the MR-signal changes. Extensive clinical work-up and follow-up, ranging from 3 months to 5 years, ruled out infection or other possible causes of brain damage. Seizure-induced brain-MRI abnormalities remained a diagnosis of exclusion. Site, characteristics and reversibility of MRI changes, and association with characteristics of seizures were determined. Results MRI showed unilateral (13/26) and bilateral abnormalities, with high (24/26) and low (2/26) T2-signal, leptomeningeal contrast-enhancement (2/26), restricted diffusion (9/19). Location of abnormality was cortical/subcortical, basal ganglia, white matter, corpus callosum, cerebellum. Hippocampus was involved in 10/26 patients. Reversibility of MRI changes was complete in 15, and with residual gliosis or focal atrophy in 11 patients. Reversibility was noted between 15 and 150 days (average, 62 days). Partial simple and complex seizures were associated with hippocampal involvement (p = 0.015), status epilepticus with incomplete reversibility of MRI abnormalities (p = 0.041). Conclusions Seizure or epileptic status can induce transient, variably reversible MRI brain abnormalities. Partial seizures are frequently associated with hippocampal involvement and status epilepticus with incompletely reversible lesions. These seizure-induced MRI abnormalities pose a broad differential diagnosis; increased awareness may reduce the risk of misdiagnosis and unnecessary intervention.

  7. 正常人音乐欣赏的脑功能磁共振激活模式研究%The study of fMRI activation pattern of normal brain music appreciation

    Institute of Scientific and Technical Information of China (English)

    刘明; 赵晶; 和清源; 庞冉; 陈云翔; 王志群

    2016-01-01

    目的:采用血氧水平依赖的脑功能磁共振成像技术( BOLD-fMRI)技术,研究正常人欣赏欢快音乐时的脑功能区定位,探讨可能的神经网络调节机制。方法选择15例正常健康受试者,年龄25~50岁,在欣赏欢快音乐同时,用BOLD-fMRI技术进行脑功能磁共振成像检查,采用SPM软件对原始数据进行统计学处理,获得平均激活图,分析激活增高的脑区。结果15例受试者在欣赏欢快音乐时大脑显著激活了视觉注意网络、默认网络、运动感觉网络、认知记忆网络的相关脑区,这些脑区可能参与了音乐的感知、注意、记忆、情绪反应等过程。结论功能磁共振成像技术在音乐欣赏的功能定位方面具有独特的价值,欢快音乐欣赏可激活大脑多种功能神经网络参与处理。%Objective By using the blood oxygen level dependent functional magnetic resonance imaging ( BOLD-fMRI ) technique, to study the normal brain function localization when listening cheerful music , and then to explore the possible neural network adjustment mechanism .Methods We selected 15 volunteers with normal mental health , age between 25~50 .While listening the cheerful music , BOLD-fMRI examinations were performed and the original image data were obtained for statistical processing by using SPM software .And then, the average activation graph was analyzed to acquire the activated brain regions . Results While the subjects listening the cheerful music , several brain networks were activated including visual attention net-work, default mode network , sensorimoter network and cognitive network .These brain regions probably involved in the Music per-ception, attention, memory, and emotional reaction process .Conclusion The application of fMRI technique in music apprecia-tion has unique value in the respect of functional localization , cheerful music can activate the brain functions involved in several neural networks .

  8. Sparse representation of brain aging: extracting covariance patterns from structural MRI.

    Directory of Open Access Journals (Sweden)

    Longfei Su

    Full Text Available An enhanced understanding of how normal aging alters brain structure is urgently needed for the early diagnosis and treatment of age-related mental diseases. Structural magnetic resonance imaging (MRI is a reliable technique used to detect age-related changes in the human brain. Currently, multivariate pattern analysis (MVPA enables the exploration of subtle and distributed changes of data obtained from structural MRI images. In this study, a new MVPA approach based on sparse representation has been employed to investigate the anatomical covariance patterns of normal aging. Two groups of participants (group 1:290 participants; group 2:56 participants were evaluated in this study. These two groups were scanned with two 1.5 T MRI machines. In the first group, we obtained the discriminative patterns using a t-test filter and sparse representation step. We were able to distinguish the young from old cohort with a very high accuracy using only a few voxels of the discriminative patterns (group 1:98.4%; group 2:96.4%. The experimental results showed that the selected voxels may be categorized into two components according to the two steps in the proposed method. The first component focuses on the precentral and postcentral gyri, and the caudate nucleus, which play an important role in sensorimotor tasks. The strongest volume reduction with age was observed in these clusters. The second component is mainly distributed over the cerebellum, thalamus, and right inferior frontal gyrus. These regions are not only critical nodes of the sensorimotor circuitry but also the cognitive circuitry although their volume shows a relative resilience against aging. Considering the voxels selection procedure, we suggest that the aging of the sensorimotor and cognitive brain regions identified in this study has a covarying relationship with each other.

  9. Repeated diffusion MRI reveals earliest time point for stratification of radiotherapy response in brain metastases

    Science.gov (United States)

    Mahmood, Faisal; Johannesen, Helle H.; Geertsen, Poul; Hansen, Rasmus H.

    2017-04-01

    An imaging biomarker for early prediction of treatment response potentially provides a non-invasive tool for better prognostics and individualized management of the disease. Radiotherapy (RT) response is generally related to changes in gross tumor volume manifesting months later. In this prospective study we investigated the apparent diffusion coefficient (ADC), perfusion fraction and pseudo diffusion coefficient derived from diffusion weighted MRI as potential early biomarkers for radiotherapy response of brain metastases. It was a particular aim to assess the optimal time point for acquiring the DW-MRI scan during the course of treatment, since to our knowledge this important question has not been addressed directly in previous studies. Twenty-nine metastases (N  =  29) from twenty-one patients, treated with whole-brain fractionated external beam RT were analyzed. Patients were scanned with a 1 T MRI system to acquire DW-, T2*W-, T2W- and T1W scans, before start of RT, at each fraction and at follow up two to three months after RT. The DW-MRI parameters were derived using regions of interest based on high b-value images (b  =  800 s mm‑2). Both volumetric and RECIST criteria were applied for response evaluation. It was found that in non-responding metastases the mean ADC decreased and in responding metastases it increased. The volume based response proved to be far more consistently predictable by the ADC change found at fraction number 7 and later, compared to the linear response (RECIST). The perfusion fraction and pseudo diffusion coefficient did not show sufficient prognostic value with either response assessment criteria. In conclusion this study shows that the ADC derived using high b-values may be a reliable biomarker for early assessment of radiotherapy response for brain metastases patients. The earliest response stratification can be achieved using two DW-MRI scans, one pre-treatment and one at treatment day 7–9 (equivalent to 21

  10. Management of intracranial incidental findings on brain MRI; Management intrakranieller Zufallsbefunde in der MRT-Bildgebung

    Energy Technology Data Exchange (ETDEWEB)

    Langner, S.; Buelow, R.; Kirsch, M. [University Medicine Greifswald (Germany). Inst. for Diagnostic Radiology and Neuroradiology; Fleck, S. [University Medicine Greifswald (Germany). Dept. of Neurosurgery; Angermaier, A. [University Medicine Greifswald (Germany). Dept. of Neurology

    2016-12-15

    The wider use of MRI for imaging of the head in both research and clinical practice has led to an increasing number of intracranial incidental findings. Most of these findings have no immediate medical consequences. Nevertheless, knowledge of common intracranial incidental findings and their clinical relevance is necessary to adequately discuss the findings with the patient. Based on the author's experiences from a large population-based study, the most common incidental MR findings in the brain will be presented, discussing their clinical relevance and giving recommendations for management according to the current literature and guidelines.

  11. Advances in the study of brain structure and function of migraine with MRI%偏头痛脑结构和功能的MRI研究进展

    Institute of Scientific and Technical Information of China (English)

    兰慧; 李康; 吕发金

    2016-01-01

    作为一原发性头痛,偏头痛表现出特征性的单侧、中、重度搏动性头痛,并且随着日常活动的增加而加剧,也常伴随恶心呕吐、畏光畏声等神经、胃肠、自主神经症状。偏头痛给患者和社会带来负担,例如增加患者的环境敏感性、造成残疾甚至丧失社会生产的能力。近年的神经影像学发现频繁的头痛发作引起了脑结构与功能的改变。该文将从MRI所显示的偏头痛脑结构与功能异常作一次回顾性分析研究。%AbstractAs an primary headache disorder, migraine is characteri zed by moderate to severe pain, which consists of unilateral and pulsating headache attacks that are typically aggravated by physical activity ,and accompanied by nausea and vomiting, photophobia, pho nophobia and other neurological, gastrointestinal, autonomic sympto-ms. Causes significant individual and societal burdens as a result of pain, such as environmental sensitivity, disability and even lost prod uctivity. Recently, advanced neuroimaging has led to an evolution in our perception of migraine pathophysiology. Numerous neuroima ging studies have detected alterations in brain structureand function in patients with migraine.In this article, we will make a retrospec tive analysis of the brain structure and function of migraine, which is shown by magnetic resonance imaging.

  12. MRI脑测谎实验方法学%Brain-Based MRI lie detection experiment methodology

    Institute of Scientific and Technical Information of China (English)

    李文石; 张好; 胡清泉; 苏香; 郭亮

    2006-01-01

    The brain-based MRI lie detection experiment methodology is reviewed for the first time, including the magnetic resonance imaging paradigm,the double-block deign,the equidistance hit-ball and the test mechanice,This paper illustrates the research results of 3D MRI lie detection and the contrastive experiment of otopoint mapping brain signature lie detection,ingeminates the lie-Truth Law(PT/PL ≤0.618)which we get from the statistic of the world MRI reports. The conclusion points out the essence of this technology,its advantages and disadvantages,and the evolution of this methodology.

  13. Texture descriptors to distinguish radiation necrosis from recurrent brain tumors on multi-parametric MRI

    Science.gov (United States)

    Tiwari, Pallavi; Prasanna, Prateek; Rogers, Lisa; Wolansky, Leo; Badve, Chaitra; Sloan, Andrew; Cohen, Mark; Madabhushi, Anant

    2014-03-01

    Di erentiating radiation necrosis (a radiation induced treatment e ect) from recurrent brain tumors (rBT) is currently one of the most clinically challenging problems in care and management of brain tumor (BT) patients. Both radiation necrosis (RN), and rBT exhibit similar morphological appearance on standard MRI making non-invasive diagnosis extremely challenging for clinicians, with surgical intervention being the only course for obtaining de nitive ground truth". Recent studies have reported that the underlying biological pathways de n- ing RN and rBT are fundamentally di erent. This strongly suggests that there might be phenotypic di erences and hence cues on multi-parametric MRI, that can distinguish between the two pathologies. One challenge is that these di erences, if they exist, might be too subtle to distinguish by the human observer. In this work, we explore the utility of computer extracted texture descriptors on multi-parametric MRI (MP-MRI) to provide alternate representations of MRI that may be capable of accentuating subtle micro-architectural di erences between RN and rBT for primary and metastatic (MET) BT patients. We further explore the utility of texture descriptors in identifying the MRI protocol (from amongst T1-w, T2-w and FLAIR) that best distinguishes RN and rBT across two independent cohorts of primary and MET patients. A set of 119 texture descriptors (co-occurrence matrix homogeneity, neighboring gray-level dependence matrix, multi-scale Gaussian derivatives, Law features, and histogram of gradient orientations (HoG)) for modeling di erent macro and micro-scale morphologic changes within the treated lesion area for each MRI protocol were extracted. Principal component analysis based variable importance projection (PCA-VIP), a feature selection method previously developed in our group, was employed to identify the importance of every texture descriptor in distinguishing RN and rBT on MP-MRI. PCA-VIP employs regression analysis to provide

  14. Human brain diffusion tensor imaging at submillimeter isotropic resolution on a 3Tesla clinical MRI scanner.

    Science.gov (United States)

    Chang, Hing-Chiu; Sundman, Mark; Petit, Laurent; Guhaniyogi, Shayan; Chu, Mei-Lan; Petty, Christopher; Song, Allen W; Chen, Nan-kuei

    2015-09-01

    The advantages of high-resolution diffusion tensor imaging (DTI) have been demonstrated in a recent post-mortem human brain study (Miller et al., NeuroImage 2011;57(1):167-181), showing that white matter fiber tracts can be much more accurately detected in data at a submillimeter isotropic resolution. To our knowledge, in vivo human brain DTI at a submillimeter isotropic resolution has not been routinely achieved yet because of the difficulty in simultaneously achieving high resolution and high signal-to-noise ratio (SNR) in DTI scans. Here we report a 3D multi-slab interleaved EPI acquisition integrated with multiplexed sensitivity encoded (MUSE) reconstruction, to achieve high-quality, high-SNR and submillimeter isotropic resolution (0.85×0.85×0.85mm(3)) in vivo human brain DTI on a 3Tesla clinical MRI scanner. In agreement with the previously reported post-mortem human brain DTI study, our in vivo data show that the structural connectivity networks of human brains can be mapped more accurately and completely with high-resolution DTI as compared with conventional DTI (e.g., 2×2×2mm(3)).

  15. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal Siddiqui

    Full Text Available A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT, principal component analysis (PCA, and least squares support vector machine (LS-SVM are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%. Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities

  16. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    Science.gov (United States)

    Siddiqui, Muhammad Faisal; Reza, Ahmed Wasif; Kanesan, Jeevan

    2015-01-01

    A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the

  17. See-through Brains and Diffusion Tensor MRI Clarified Fiber Connections: A Preliminary Microstructural Study in a Mouse with Callosal Agenesis.

    Science.gov (United States)

    Kerever, Aurelien; Kamagata, Koji; Yokosawa, Suguru; Otake, Yosuke; Ochi, Hisaaki; Yamada, Taihei; Hori, Masaaki; Kamiya, Kouhei; Nishikori, Akira; Aoki, Shigeki; Arikawa-Hirasawa, Eri

    2015-01-01

    Clearing methods that render the brain optically transparent allow high-resolution three-dimensional (3D) imaging of neural networks. We used diffusion tensor imaging (DTI) and two-photon imaging of cleared brains to analyze white matter in BTBR mice. We confirmed corpus callosum agenesis and identified an abnormal commissure close to the third ventricle. DTI and cleared-brain two-photon imaging revealed that these commissural fibers constituted a frontal clustering of the ventral hippocampal commissure and provided a detailed assessment of white matter structure in mice.

  18. Emerging role of functional brain MRI in low-grade glioma surgery

    DEFF Research Database (Denmark)

    Friismose, Ancuta; Traise, Peter; Markovic, Ljubo

    Learning objectives 1. To describe the use of functional MRI (fMRI) in cranial surgery planning for patients with low-grade gliomas (LGG). 2. To show the increasing importance of fMRI in the clinical setting. Background LGG include brain tumors classified by the World Health Organization as grade I...... be used to map eloquent cortex areas, thus minimizing postoperative deficits and improving surgical performance. Findings and procedure details Patients diagnosed with low-grade gliomas located in eloquent brain areas undergo fMRI prior to surgery. The exams are performed on a 3T MR system (Achieva TX....... Language comprehension and visual tasks can be added to visualize Wernicke’s area or the visual cortex. Diffusion tensor imaging (DTI) is used to map nerve tract course relative to the tumour. Conclusion FMRI has proven its clinical utility in locating eloquent brain areas with relation to tumor site...

  19. Efficacy and toxicity in brain tumor treatment - quantitative Measurements using advanced MRI

    DEFF Research Database (Denmark)

    Ravn, Søren

    2016-01-01

    and are now being used for presurgical and radiation therapy (RT) planning. More advanced MRI sequences have gained attention. Sequences such as diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI) and functional magnetic resonance imaging (fMRI) have entered the clinical world concurrently......From the clinical introduction in the 1980s, MRI has grown to become an indispensable brain imaging modality, mainly due to its excellent ability to visualize soft tissues. Morphologically, T1- and T2-weighted brain tumor MRI have been part of routine diagnostic radiology for more than two decades...... with the introduction of magnets with higher field strength. Ongoing technical development has enabled a change from semiquantitative measurements to a true quantitative approach. This step is expected to have a great impact on the treatment of brain tumor patients in the future. The aim of this Ph.D. dissertation...

  20. Impact of Global Normalization in fMRI Acupuncture Studies

    Directory of Open Access Journals (Sweden)

    Jinbo Sun

    2012-01-01

    Full Text Available Global normalization is often used as a preprocessing step for dispelling the “nuisance effects.” However, it has been shown in cognitive and emotion tasks that this preprocessing step might greatly distort statistical results when the orthogonality assumption of global normalization is violated. The present study examines this issue in fMRI acupuncture studies. Thirty healthy subjects were recruited to evaluate the impacts of the global normalization on the BOLD responses evoked by acupuncture stimulation during De-qi sensation and tactile stimulation during nonpainful sensations. To this end, we compared results by conducting global normalization (PSGS and not conducting global normalization (NO PSGS based on a proportional scaling model. The orthogonality assumption of global normalization was violated, and significant changes between BOLD responses for NO PSGS and PSGS were shown in most subjects. Extensive deactivations of acupuncture in fMRI were the non-specifically pernicious consequences of global normalization. The central responses of acupuncture during De-qi are non-specifically activation-dominant at the somatosensory-related brain network, whose statistical power is specifically enhanced by PSGS. In conclusion, PSGS should be unjustified for acupuncture studies in fMRI. The differences including the global normalization or not may partly contribute to conflicting results and interpretations in previous fMRI acupuncture studies.

  1. Human memory retention and recall processes. A review of EEG and fMRI studies.

    Science.gov (United States)

    Amin, Hafeezullah; Malik, Aamir S

    2013-10-01

    Human memory is an important concept in cognitive psychology and neuroscience. Our brain is actively engaged in functions of learning and memorization. Generally, human memory has been classified into 2 groups: short-term/working memory, and long-term memory. Using different memory paradigms and brain mapping techniques, psychologists and neuroscientists have identified 3 memory processes: encoding, retention, and recall. These processes have been studied using EEG and functional MRI (fMRI) in cognitive and neuroscience research. This study reviews previous research reported for human memory processes, particularly brain behavior in memory retention and recall processes with the use of EEG and fMRI. We discuss issues and challenges related to memory research with EEG and fMRI techniques.

  2. Incidental sinus abnormalities in 256 patients referred for brain MRI

    Directory of Open Access Journals (Sweden)

    Ghanaati H

    2007-06-01

    Full Text Available Background: Imaging abnormalities in the paranasal sinuses are regularly noted as incidental findings on MRI, however, little is known about their prevalence in the Iranian population. The purpose of this study was to classify these findings in the paranasal sinuses as seen on MRI and to investigate the prevalence, according to site and type of paranasal abnormality. Methods: In this cross-sectional study, the T2-weighted axial MRI of 256 patients with diseases unrelated to their paranasal sinuses were reviewed between May 2002 and June 2003. The findings were categorized according to the anatomic location and the imaging characteristics of the abnormality. The abnormalities recorded included total sinus opacification, mucoperiosteal thickening >5mm, air fluid levels and retention cysts or polyps. Unilateral or bilateral involvement and septal deviation were also noted. A sinus was considered normal if it was fully aerated and no soft-tissue density was apparent within the cavity. Results: Among our cases, 111 (43.5% were male and 145 (56.5% were female. Of these patients, abnormalities in one or more of the sinus groups were found in 110 subjects (42.9%, 55.5% of which were male and 44.5% were female (P=0.001. Maxillary sinus abnormalities were observed in 66.4% of the patients, while ethmoid sinus abnormalities were found in 63.6%. Of the ethmoid abnormalities, 21% were found in the anterior section, 9% in the middle ethmoid, and 8% in the posterior ethmoid. The most common abnormality found was mucosal thickening. Among our cases, 23.4% had septal deviation, which was significantly higher among those with sinusitis (29% versus 19.1%; P<0.01. Of those patients with sinus involvement, 16% were involved in the sphenoid sinus and 5% in the frontal sinus. The results obtained from the patients with sinus abnormality revealed that 85% suffered from cough, nasal obstruction, runny nose, facial pain and post nasal discharge and 24% had been diagnosed

  3. Disturbed spontaneous brain activity pattern in patients with primary angle-closure glaucoma using amplitude of low-frequency fluctuation: a fMRI study

    Directory of Open Access Journals (Sweden)

    Huang X

    2015-07-01

    Full Text Available Xin Huang,1,* Yu-Lin Zhong,1,* Xian-Jun Zeng,2 Fuqing Zhou,2 Xin-Hua Liu,1 Pei-Hong Hu,1 Chong-Gang Pei,1 Yi Shao,1 Xi-Jian Dai21Department of Ophthalmology, 2Department of Radiology, The First Affiliated Hospital of Nanchang University, Nangchang, Jiangxi, People’s Republic of China*These authors contributed equally to this workObjective: The aim of this study is to use amplitude of low-frequency fluctuation (ALFF as a method to explore the local features of spontaneous brain activity in patients with primary angle -closure glaucoma (PACG and ALFFs relationship with the behavioral performances.Methods: A total of twenty one patients with PACG (eight males and 13 females, and twenty one healthy subjects (nine males and twelve females closely matched in age, sex, and education, each underwent a resting-state functional magnetic resonance imaging scan. The ALFF method was used to assess the local features of spontaneous brain activity. The correlation analysis was used to explore the relationships between the observed mean ALFF signal values of the different areas in PACG patients and the thickness of the retinal nerve fiber layer (RNFL. Results: Compared with the healthy subjects, patients with PACG had significant lower ALFF areas in the left precentral gyrus, bilateral middle frontal gyrus, bilateral superior frontal gyrus, right precuneus, and right angular gyrus, and higher areas in the right precentral gyrus. In the PACG group, there were significant negative correlations between the mean ALFF signal value of the right middle frontal gyrus and the left mean RNFL thickness (r=-0.487, P=0.033, and between the mean ALFF signal value of the left middle frontal gyrus and the right mean RNFL thickness (r=-0.504, P=0.020. Conclusion: PACG mainly involved in the dysfunction in the frontal lobe, which may reflect the underlying pathologic mechanism of PACG.Keywords: angle-closure glaucoma, amplitude of low-frequency fluctuation, functional

  4. An MRI-based atlas and database of the developing mouse brain.

    Science.gov (United States)

    Chuang, Nelson; Mori, Susumu; Yamamoto, Akira; Jiang, Hangyi; Ye, Xin; Xu, Xin; Richards, Linda J; Nathans, Jeremy; Miller, Michael I; Toga, Arthur W; Sidman, Richard L; Zhang, Jiangyang

    2011-01-01

    The advent of mammalian gene engineering and genetically modified mouse models has led to renewed interest in developing resources for referencing and quantitative analysis of mouse brain anatomy. In this study, we used diffusion tensor imaging (DTI) for quantitative characterization of anatomical phenotypes in the developing mouse brain. As an anatomical reference for neuroscience research using mouse models, this paper presents DTI based atlases of ex vivo C57BL/6 mouse brains at several developmental stages. The atlas complements existing histology and MRI-based atlases by providing users access to three-dimensional, high-resolution images of the developing mouse brain, with distinct tissue contrasts and segmentations of major gray matter and white matter structures. The usefulness of the atlas and database was demonstrated by quantitative measurements of the development of major gray matter and white matter structures. Population average images of the mouse brain at several postnatal stages were created using large deformation diffeomorphic metric mapping and their anatomical variations were quantitatively characterized. The atlas and database enhance our ability to examine the neuroanatomy in normal or genetically engineered mouse strains and mouse models of neurological diseases.

  5. Correlation of oxygenation and perfusion sensitive MRI with invasive micro probe measurements in healthy mice brain.

    Science.gov (United States)

    Sedlacik, Jan; Reitz, Matthias; Bolar, Divya S; Adalsteinsson, Elfar; Schmidt, Nils O; Fiehler, Jens

    2015-03-01

    The non-invasive assessment of (patho-)physiological parameters such as, perfusion and oxygenation, is of great importance for the characterization of pathologies e.g., tumors, which may be helpful to better predict treatment response and potential outcome. To better understand the influence of physiological parameters on the investigated oxygenation and perfusion sensitive MRI methods, MRI measurements were correlated with subsequent invasive micro probe measurements during free breathing conditions of air, air+10% CO2 and 100% O2 in healthy mice brain. MRI parameters were the irreversible (R2), reversible (R2') and effective (R2*) transverse relaxation rates, venous blood oxygenation level assessed by quantitative blood oxygenation level dependent (qBOLD) method and cerebral blood flow (CBF) assessed by arterial spin labeling (ASL) using a 7 T small animal MRI scanner. One to two days after MRI, tissue perfusion and pO2 were measured by Laser-Doppler flowmetry and fluorescence quenching micro probes, respectively. The tissue pO2 values were converted to blood oxygen saturation by using the Hill equation. The animals were anesthetized by intra peritoneal injection of ketamine-xylazine-acepromazine (10-2-0.3 mg/ml · kg). Results for normal/hypercapnia/hyperoxia conditions were: R2[s(∧)-1] = 20.7/20.4/20.1, R2*[s(∧)-1] = 31.6/29.6/25.9, R2'[s-(∧)1] = 10.9/9.2/5.7, qBOLD venous blood oxygenation level = 0.43/0.51/0.56, CBF[ml · min(∧)-1 · 100 g(∧)-1] = 70.6/105.5/81.8, Laser-Doppler flowmetry[a.u.] = 89.2/120.2/90.6 and pO2[mmHg] = 6.3/32.3/46.7. All parameters were statistically significantly different with P oxygen saturation = 0.02/0.34/0.63, showed only very limited agreement with the qBOLD venous blood oxygenation level. We found good correlation between MRI and micro probe measurements. However, direct conversion of tissue pO2 to blood oxygen saturation by using the Hill equation is very limited. Furthermore, adverse effects of anesthesia and

  6. Which fMRI clustering gives good brain parcellations?

    Directory of Open Access Journals (Sweden)

    Bertrand eThirion

    2014-07-01

    Full Text Available Analysis and interpretation of neuroimaging data often require one to divide the brain into a number of regions, or parcels, with homogeneous characteristics, be these regions defined in the brain volume or on on the cortical surface. While predefined brain atlases do not adapt to the signal in the individual subjects images, parcellation approaches use brain activity (e.g. found in some functional contrasts of interest and clustering techniques to define regions with some degree of signal homogeneity. In this work, we address the question of which clustering technique is appropriate and how to optimize the corresponding model. We use two principled criteria: goodness of fit (accuracy, and reproducibility of the parcellation across bootstrap samples. We study these criteria on both simulated and two task-based functional Magnetic Resonance Imaging datasets for the Ward, spectral and K-means clustering algorithms. We show that in general Ward’s clustering performs better than alternative methods with regards to reproducibility and accuracy and that the two criteria diverge regarding the preferred models (reproducibility leading to more conservative solutions, thus deferring the practical decision to a higher level alternative, namely the choice of a trade-off between accuracy and stability.

  7. Diffusion-weighted MRI of myelination in the rat brain following treatment with gonadal hormones

    Energy Technology Data Exchange (ETDEWEB)

    Prayer, D. [Department of Radiology, Section of Neuroradiology, University of Vienna (Austria); Roberts, T. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Barkovich, A.J. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Prayer, L. [Department of Radiology, Section of Neuroradiology, University of Vienna (Austria); Kucharczyk, J. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Moseley, M. [Department of Radiology, Section of Neuroradiology, University of California at San Francisco (UCSF), CA (United States); Arieff, A. [Department of Medicine, Geriatrics Section, Veteran`s Affairs Medical Center and University of California at San Francisco (UCSF), CA (United States)

    1997-05-01

    Previous studies have demonstrated the ability of high-resolution diffusion-weighted MRI to show maturation of white-matter structures in the developing rat brain. The purpose of this study was to investigate the influence of gonadal steroid hormones on the rate of this development. Starting from their second postnatal day, 16 rat-pups of either sex were repeatedly treated with subcutaneous implants containing 17-beta estradiol or delta-androstene 3,17 dione, respectively. Serial T1-, T2- and diffusion-weighted MRI was performed weekly for 8 weeks using a 4.7 T unit. Maturation of anterior optic pathways and hemisphere commissures was assessed. Diffusion-weighted images were processed to produce ``anisotropy index maps``, previously shown to be sensitive to white-matter maturation. Compared with untreated rat-pups, estrogen-treated animals showed accelerated, and testosterone-treated animals delayed maturation on anisotropy index maps and histological sections. In all animals, maturational changes appeared earlie on anisotropy index maps than on other MRI sequences or on myelin-sensitive stained sections. Diffusion-weighted imaging, and the construction of spatial maps sensitive to diffusion anisotropy, seem to be the most sensitive approach for the detection of maturational white-matter changes, and thus may hold potential for early diagnosis of temporary delay or permanent disturbances of white-matter development. (orig.). With 6 figs., 1 tab.

  8. MRI/MRA evaluation of sickle cell disease of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, Robert A. [Childrens Hospital, Department of Radiology, Philadelphia, PA (United States)

    2005-03-01

    Sickle cell disease is a major cause of pediatric stroke. Understanding the disease that affects the brain as infarctions, both clinically apparent and silent, requires an understanding of how the blood vessels are affected, the way in which both the brain and the blood vessels are imaged by MRI and MRA and the mechanism of injury. (orig.)

  9. Classification of normal and pathological aging processes based on brain MRI morphology measures

    Science.gov (United States)

    Perez-Gonzalez, J. L.; Yanez-Suarez, O.; Medina-Bañuelos, V.

    2014-03-01

    Reported studies describing normal and abnormal aging based on anatomical MRI analysis do not consider morphological brain changes, but only volumetric measures to distinguish among these processes. This work presents a classification scheme, based both on size and shape features extracted from brain volumes, to determine different aging stages: healthy control (HC) adults, mild cognitive impairment (MCI), and Alzheimer's disease (AD). Three support vector machines were optimized and validated for the pair-wise separation of these three classes, using selected features from a set of 3D discrete compactness measures and normalized volumes of several global and local anatomical structures. Our analysis show classification rates of up to 98.3% between HC and AD; of 85% between HC and MCI and of 93.3% for MCI and AD separation. These results outperform those reported in the literature and demonstrate the viability of the proposed morphological indexes to classify different aging stages.

  10. Dynamic MRI study for breast tumors

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Tsuneaki (Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine)

    1990-10-01

    Application of MRI for diagnosis of breast tumors was retrospectively examined in 103 consecutive cases. Contrast enhancement, mostly by dynamic study, was performed in 83 cases using Gd-DTPA and 0.5 T superconductive apparatus. Results were compared to those of mammography and sonography. On dynamic study, carcinoma showed abrupt rise of signal intensity with clear-cut peak formation in early phase, while benign fibroadenoma showed slow rise of signal intensity and prolonged enhancement without peak formation. In 12 of 33 carcinomas (33%), peripheral ring enhancement was noted reflecting vascular stroma of histologic sections. All fibroadenomas showed homogenous enhancement without peripheral ring. In MRI, sensitivity, specificity, and accuracy were 86%, 96%, 91%. In mammography 82%, 95%, 87% and in ultrasonography 91%, 95%, 93%. Although MRI should not be regarded as routine diagnostic procedure because of expense and limited availability, it may afford useful additional information when standard mammographic findings are not conclusive. (author).

  11. Analysis of large brain MRI databases for investigating the relationships between brain, cognitive, and genetic polymorphisms

    Energy Technology Data Exchange (ETDEWEB)

    Mazoyer, B

    2006-07-01

    A major challenge for the years to come is the understanding of the brain-behaviour relationships, and in particular the investigation and quantification of the impact of genetic polymorphism on these relationships. In this framework, a promising experimental approach, which we will refer to as neuro-epidemiologic imaging, consists in acquiring multimodal (brain images, psychometric an d sociological data, genotypes) data in large (several hundreds or thousands ) cohorts of subjects. Processing of such large databases requires on first place the conception and implementation of automated 'pipelines', including image registration, spatial normalisation tissue segmentation, and multivariate statistical analysis. Given the number of images and data to be processed, such pipelines must be both fully automated and robust enough to be able to handle multi-center MRI data, e.g. having inhomogeneous characteristics in terms of resolution and contrast. This approach will be illustrated using two databases collected in aged healthy subjects, searching for the impact of genetic and environmental on two markers of brain aging, namely white matter hyper-signals, and grey matter atrophy. (author)

  12. Assessment of T2- and T1-weighted MRI brain lesion load in patients with subcortical vascular encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Gass, A.; Oster, M.; Cohen, S.; Daffertshofer, M.; Schwartz, A.; Hennerici, M.G. [Neurologische Universitaetsklinik, Klinikum Mannheim der Universitaet Heidelberg (Germany)

    1998-08-01

    Previous cross-sectional studies in patients with subcortical vascular encephalopathy (SVE) have shown little or no correlation between brain lesion load and clinical disability, which could be due to the low specificity of T2-weighted MRI. Recent studies have indicated that T1-weighted MRI may be more specific than T2-weighted MRI for severe tissue destruction. We studied 37 patients with a diagnosis of SVE and 11 normal controls with standardised T1- and T2-weighted MRI. All patients underwent detailed clinical assessment including a neuropsychological test battery and computerised gait analysis. Both the T2- and T1-weighted total MRI lesion loads different between patients and controls different, particularly T1. The ratio of T2-/T1-weighted lesion load was lower in controls than in patients. There was no overall correlation of T1- or T2-weighted lesion load with clinical disability, but group comparison of patients with severe and mild clinical deficits showed different lesion loads. We suggest that T1- and T2-weighted MRI lesion loads demonstrate relevant structural abnormality in patients with SVE. (orig.) With 1 fig., 25 refs.

  13. Statistical approach of measurement of signal to noise ratio in according to change pulse sequence on brain MRI meningioma and cyst images

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eul Kyu [Inje Paik University Hospital Jeo-dong, Seoul (Korea, Republic of); Choi, Kwan Woo [Asan Medical Center, Seoul (Korea, Republic of); Jeong, Hoi Woun [The Baekseok Culture University, Cheonan (Korea, Republic of); Jang, Seo Goo [The Soonchunhyang University, Asan (Korea, Republic of); Kim, Ki Won [Kyung Hee University Hospital at Gang-dong, Seoul (Korea, Republic of); Son, Soon Yong [The Wonkwang Health Science University, Iksan (Korea, Republic of); Min, Jung Whan; Son, Jin Hyun [The Shingu University, Sungnam (Korea, Republic of)

    2016-09-15

    The purpose of this study was to needed basis of measure MRI CAD development for signal to noise ratio (SNR) by pulse sequence analysis from region of interest (ROI) in brain magnetic resonance imaging (MRI) contrast. We examined images of brain MRI contrast enhancement of 117 patients, from January 2005 to December 2015 in a University-affiliated hospital, Seoul, Korea. Diagnosed as one of two brain diseases such as meningioma and cysts SNR for each patient's image of brain MRI were calculated by using Image J. Differences of SNR among two brain diseases were tested by SPSS Statistics21 ANOVA test for there was statistical significance (p < 0.05). We have analysis socio-demographical variables, SNR according to sequence disease, 95% confidence according to SNR of sequence and difference in a mean of SNR. Meningioma results, with the quality of distributions in the order of T1CE, T2 and T1, FLAIR. Cysts results, with the quality of distributions in the order of T2 and T1, T1CE and FLAIR. SNR of MRI sequences of the brain would be useful to classify disease. Therefore, this study will contribute to evaluate brain diseases, and be a fundamental to enhancing the accuracy of CAD development.

  14. Early development of arterial spin labeling to measure regional brain blood flow by MRI.

    Science.gov (United States)

    Koretsky, Alan P

    2012-08-15

    Two major avenues of work converged in the late 1980's and early 1990's to give rise to brain perfusion MRI. The development of anatomical brain MRI quickly had as a major goal the generation of angiograms using tricks to label flowing blood in macroscopic vessels. These ideas were aimed at getting information about microcirculatory flow as well. Over the same time course the development of in vivo magnetic resonance spectroscopy had as its primary goal the assessment of tissue function and in particular, tissue energetics. For this the measurement of the delivery of water to tissue was critical for assessing tissue oxygenation and viability. The measurement of the washin/washout of "freely" diffusible tracers by spectroscopic based techniques pointed the way for quantitative approaches to measure regional blood flow by MRI. These two avenues came together in the development of arterial spin labeling (ASL) MRI techniques to measure regional cerebral blood flow. The early use of ASL to measure brain activation to help verify BOLD fMRI led to a rapid development of ASL based perfusion MRI. Today development and applications of regional brain blood flow measurements with ASL continues to be a major area of activity.

  15. Evaluation of MRI and cannabinoid type 1 receptor PET templates constructed using DARTEL for spatial normalization of rat brains

    Energy Technology Data Exchange (ETDEWEB)

    Kronfeld, Andrea; Müller-Forell, Wibke [Institute of Neuroradiology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, Mainz 55131 (Germany); Buchholz, Hans-Georg; Maus, Stephan; Reuss, Stefan; Schreckenberger, Mathias; Miederer, Isabelle, E-mail: isabelle.miederer@unimedizin-mainz.de [Department of Nuclear Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, Mainz 55131 (Germany); Lutz, Beat [Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Duesbergweg 6, Mainz 55128 (Germany)

    2015-12-15

    Purpose: Image registration is one prerequisite for the analysis of brain regions in magnetic-resonance-imaging (MRI) or positron-emission-tomography (PET) studies. Diffeomorphic anatomical registration through exponentiated Lie algebra (DARTEL) is a nonlinear, diffeomorphic algorithm for image registration and construction of image templates. The goal of this small animal study was (1) the evaluation of a MRI and calculation of several cannabinoid type 1 (CB1) receptor PET templates constructed using DARTEL and (2) the analysis of the image registration accuracy of MR and PET images to their DARTEL templates with reference to analytical and iterative PET reconstruction algorithms. Methods: Five male Sprague Dawley rats were investigated for template construction using MRI and [{sup 18}F]MK-9470 PET for CB1 receptor representation. PET images were reconstructed using the algorithms filtered back-projection, ordered subset expectation maximization in 2D, and maximum a posteriori in 3D. Landmarks were defined on each MR image, and templates were constructed under different settings, i.e., based on different tissue class images [gray matter (GM), white matter (WM), and GM + WM] and regularization forms (“linear elastic energy,” “membrane energy,” and “bending energy”). Registration accuracy for MRI and PET templates was evaluated by means of the distance between landmark coordinates. Results: The best MRI template was constructed based on gray and white matter images and the regularization form linear elastic energy. In this case, most distances between landmark coordinates were <1 mm. Accordingly, MRI-based spatial normalization was most accurate, but results of the PET-based spatial normalization were quite comparable. Conclusions: Image registration using DARTEL provides a standardized and automatic framework for small animal brain data analysis. The authors were able to show that this method works with high reliability and validity. Using DARTEL

  16. Application of quantitative MRI for brain tissue segmentation at 1.5 T and 3.0 T field strengths.

    Directory of Open Access Journals (Sweden)

    Janne West

    Full Text Available BACKGROUND: Brain tissue segmentation of white matter (WM, grey matter (GM, and cerebrospinal fluid (CSF are important in neuroradiological applications. Quantitative Mri (qMRI allows segmentation based on physical tissue properties, and the dependencies on MR scanner settings are removed. Brain tissue groups into clusters in the three dimensional space formed by the qMRI parameters R1, R2 and PD, and partial volume voxels are intermediate in this space. The qMRI parameters, however, depend on the main magnetic field strength. Therefore, longitudinal studies can be seriously limited by system upgrades. The aim of this work was to apply one recently described brain tissue segmentation method, based on qMRI, at both 1.5 T and 3.0 T field strengths, and to investigate similarities and differences. METHODS: In vivo qMRI measurements were performed on 10 healthy subjects using both 1.5 T and 3.0 T MR scanners. The brain tissue segmentation method was applied for both 1.5 T and 3.0 T and volumes of WM, GM, CSF and brain parenchymal fraction (BPF were calculated on both field strengths. Repeatability was calculated for each scanner and a General Linear Model was used to examine the effect of field strength. Voxel-wise t-tests were also performed to evaluate regional differences. RESULTS: Statistically significant differences were found between 1.5 T and 3.0 T for WM, GM, CSF and BPF (p<0.001. Analyses of main effects showed that WM was underestimated, while GM and CSF were overestimated on 1.5 T compared to 3.0 T. The mean differences between 1.5 T and 3.0 T were -66 mL WM, 40 mL GM, 29 mL CSF and -1.99% BPF. Voxel-wise t-tests revealed regional differences of WM and GM in deep brain structures, cerebellum and brain stem. CONCLUSIONS: Most of the brain was identically classified at the two field strengths, although some regional differences were observed.

  17. Does Somatosensory Discrimination Activate Different Brain Areas in Children with Unilateral Cerebral Palsy Compared to Typically Developing Children? An fMRI Study

    Science.gov (United States)

    Van de Winckel, Ann; Verheyden, Geert; Wenderoth, Nici; Peeters, Ron; Sunaert, Stefan; Van Hecke, Wim; De Cock, Paul; Desloovere, Kaat; Eyssen, Maria; Feys, Hilde

    2013-01-01

    Aside from motor impairment, many children with unilateral cerebral palsy (CP) experience altered tactile, proprioceptive, and kinesthetic awareness. Sensory deficits are addressed in rehabilitation programs, which include somatosensory discrimination exercises. In contrast to adult stroke patients, data on brain activation, occurring during…

  18. Detection of electroporation-induced membrane permeabilization states in the brain using diffusion-weighted MRI

    DEFF Research Database (Denmark)

    Mahmood, Faisal; Hansen, Rasmus H; Agerholm-Larsen, Birgit

    2015-01-01

    (DW-MRI) as a quantitative method for detecting EP-induced membrane permeabilization of brain tissue using a rat brain model. MATERIAL AND METHODS: Fifty-four anesthetized Sprague-Dawley male rats were electroporated in the right hemisphere, using different voltage levels to induce no permeabilization......-induced permeabilization of brain tissue and to some extent of differentiating NP, TMP and PMP using appropriate scan timing....

  19. Implementing Tumor Detection and Area Calculation in Mri Image of Human Brain Using Image Processing Techniques

    OpenAIRE

    Sunil L. Bangare; Madhura Patil

    2015-01-01

    This paper is based on the research on Human Brain Tumor which uses the MRI imaging technique to capture the image. In this proposed work Brain Tumor area is calculated to define the Stage or level of seriousness of the tumor. Image Processing techniques are used for the brain tumor area calculation and Neural Network algorithms for the tumor position calculation. Also in the further advancement the classification of the tumor based on few parameters is also expected. Proposed wor...

  20. AN IMPROVED TECHNIQUE FOR IDENTIFICATION AND CLASSIFICATION OF BRAIN DISORDER FROM MRI BRAIN IMAGE

    Directory of Open Access Journals (Sweden)

    Finitha Joseph

    2015-11-01

    Full Text Available Medical image processing is developing recently due to its wide applications. An efficient MRI image segmentation is needed at present. In this paper, MRI brain segmentation is done by Semi supervised learning which does not require pathology modelling and, thus, allows high degree of automation. In abnormality detection, a vector is characterized as anomalous if it does not comply with the probability distribution obtained from normal data. The estimation of the probability density function, however, is usually not feasible due to large data dimensionality. In order to overcome this challenge, we treat every image as a network of locally coherent image partitions (overlapping blocks. We formulate and maximize a strictly concave likelihood function estimating abnormality for each partition and fuse the local estimates into a globally optimal estimate that satisfies the consistency constraints, based on a distributed estimation algorithm. After this features are extracted by Gray-Level Co-occurrence Matrices (GLCM algorithm and those features are given to Particle Spam Optimization (PSO and finally classification is done by using Library Support Vector Machine (LIBSVM.Thus results are evaluated and proved its efficiency using accuracy.

  1. Integration of ultra-high field MRI and histology for connectome based research of brain disorders

    Directory of Open Access Journals (Sweden)

    Shan eYang

    2013-09-01

    Full Text Available Ultra-high field magnetic resonance imaging (MRI became increasingly relevant for in vivo neuroscientific research because of improved spatial resolutions. However, this is still the unchallenged domain of histological studies, which long played an important role in the investigation of neuropsychiatric disorders. While the field of biological psychiatry strongly advanced on macroscopic levels, current developments are rediscovering the richness of immunohistological information when attempting a multi-level systematic approach to brain function and dysfunction. For most studies, histology sections lost information on three-dimensional reconstructions. Translating histological sections to 3D-volumes would thus not only allow for multi-stain and multi-subject alignment in post mortem data, but also provide a crucial step in big data initiatives involving the network analyses currently performed with in vivo MRI. We therefore investigated potential pitfalls during integration of MR and histological information where no additional blockface information is available. We demonstrated that strengths and requirements from both methods seem to be ideally merged at a spatial resolution of 200 μm. However, the success of this approach is heavily dependent on choices of hardware, sequence and reconstruction. We provide a fully automated pipeline that optimizes histological 3D reconstructions, providing a potentially powerful solution not only for primary human post mortem research institutions in neuropsychiatric research, but also to help alleviate the massive workloads in neuroanatomical atlas initiatives. We further demonstrate (for the first time the feasibility and quality of ultra-high spatial resolution (150 µm isotopic imaging of the entire human brain MRI at 7T, offering new opportunities for analyses on MR-derived information.

  2. Rey's Auditory Verbal Learning Test scores can be predicted from whole brain MRI in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Elaheh Moradi

    2017-01-01

    Full Text Available Rey's Auditory Verbal Learning Test (RAVLT is a powerful neuropsychological tool for testing episodic memory, which is widely used for the cognitive assessment in dementia and pre-dementia conditions. Several studies have shown that an impairment in RAVLT scores reflect well the underlying pathology caused by Alzheimer's disease (AD, thus making RAVLT an effective early marker to detect AD in persons with memory complaints. We investigated the association between RAVLT scores (RAVLT Immediate and RAVLT Percent Forgetting and the structural brain atrophy caused by AD. The aim was to comprehensively study to what extent the RAVLT scores are predictable based on structural magnetic resonance imaging (MRI data using machine learning approaches as well as to find the most important brain regions for the estimation of RAVLT scores. For this, we built a predictive model to estimate RAVLT scores from gray matter density via elastic net penalized linear regression model. The proposed approach provided highly significant cross-validated correlation between the estimated and observed RAVLT Immediate (R = 0.50 and RAVLT Percent Forgetting (R = 0.43 in a dataset consisting of 806 AD, mild cognitive impairment (MCI or healthy subjects. In addition, the selected machine learning method provided more accurate estimates of RAVLT scores than the relevance vector regression used earlier for the estimation of RAVLT based on MRI data. The top predictors were medial temporal lobe structures and amygdala for the estimation of RAVLT Immediate and angular gyrus, hippocampus and amygdala for the estimation of RAVLT Percent Forgetting. Further, the conversion of MCI subjects to AD in 3-years could be predicted based on either observed or estimated RAVLT scores with an accuracy comparable to MRI-based biomarkers.

  3. PWI-MRI and contrast extravasation in brain AVM help to estimate angiogenic activity

    Energy Technology Data Exchange (ETDEWEB)

    Saliou, Guillaume; Toulgoat, Frederique; Ozanne, Augustin; Lasjaunias, Pierre; Ducreux, Denis [Hopital de Bicetre, Service de Neuroradiologie, Kremlin Bicetre cedex (France); Krings, Timo [Hopital de Bicetre, Service de Neuroradiologie, Kremlin Bicetre cedex (France); University of Toronto, Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, UHN, Toronto, ON (Canada); Rutgers, Dik R. [Hopital de Bicetre, Service de Neuroradiologie, Kremlin Bicetre cedex (France); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands)

    2011-10-15

    The aim of this study is to investigate perfusion characteristics of brain arteriovenous malformation (AVM) by means of MRI perfusion-weighted imaging (PWI). Forty-three patients with brain AVM were prospectively included and investigated by PWI-MRI. Diagnosis of type of disease was made by angiogram. According to angiographic features, the study group was classified in three groups: two groups of patients with classical AVM (group 1 with few or no angiogenic feature (13 patients) and group 2 with many angiogenic features (18 patients)) and one group (group 3) which included patients with cerebral proliferative angiopathy (CPA; 12 patients). Twenty-one patients had never been treated endovascularly for their AVM and 22 patients received partial treatment by endovascular embolisation. Through PWI, corrected cerebral blood volume (CBVc), mean transit time (MTT), and percentage of microvascular leakage (MVL) as an indirect measure of permeability were assessed. The three patient groups did not differ significantly in baseline and clinical parameters. CBVc, MTT, and MVL differed significantly between the three groups (p = 0.003, p = 0.04, p = 0.01, respectively), with the lowest mean values found in group 1 and the highest in group 3. Mean MVL was 11.4 in group 1, 18.6 in group 2, and 21.9 in group 3. MRI can demonstrate differences in PWI parameters among patients with classical AVM and CPA, which are related to angiographic features of these AVMs. Through PWI, the level of angiogenic activity in AVMs may be monitored. (orig.)

  4. Diagnostic benefits of presurgical fMRI in patients with brain tumours in the primary sensorimotor cortex

    Energy Technology Data Exchange (ETDEWEB)

    Wengenroth, Martina; Blatow, M.; Guenther, J. [University of Heidelberg Medical School, Department of Neuroradiology, Heidelberg (Germany); Akbar, M. [University of Heidelberg Medical School, Department of Orthopaedics, Heidelberg (Germany); Tronnier, V.M. [University of Schleswig-Holstein, Department of Neurosurgery, Luebeck (Germany); Stippich, C. [University Hospital Basle, Department of Diagnostic and Interventional Neuroradiology, Basle (Switzerland)

    2011-07-15

    Reliable imaging of eloquent tumour-adjacent brain areas is necessary for planning function-preserving neurosurgery. This study evaluates the potential diagnostic benefits of presurgical functional magnetic resonance imaging (fMRI) in comparison to a detailed analysis of morphological MRI data. Standardised preoperative functional and structural neuroimaging was performed on 77 patients with rolandic mass lesions at 1.5 Tesla. The central region of both hemispheres was allocated using six morphological and three functional landmarks. fMRI enabled localisation of the motor hand area in 76/77 patients, which was significantly superior to analysis of structural MRI (confident localisation of motor hand area in 66/77 patients; p < 0.002). FMRI provided additional diagnostic information in 96% (tongue representation) and 97% (foot representation) of patients. FMRI-based presurgical risk assessment correlated in 88% with a positive postoperative clinical outcome. Routine presurgical FMRI allows for superior assessment of the spatial relationship between brain tumour and motor cortex compared with a very detailed analysis of structural 3D MRI, thus significantly facilitating the preoperative risk-benefit assessment and function-preserving surgery. The additional imaging time seems justified. FMRI has the potential to reduce postoperative morbidity and therefore hospitalisation time. (orig.)

  5. Flow velocity change in the cortical vein during motor activation and its effect on functional brain MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Kazuhiro [Kyoto Prefectural Univ. of Medicine (Japan)

    1998-06-01

    On the brain functional magnetic resonance imaging (fMRI) using the gradient-recalled echo technique with clinical MR scanner, the activated areas nearly correspond with the cortical veins. This suggests that the fMRI signal mainly originates from the cortical veins. In this study, we analyzed the flow velocity in the cortical vein quantitatively during brain activation and resting status using 2 dimensional time-of-flight cine MR venography (2D-TOF-cine-MRV) and 2 dimensional phase contrast MRV (2D-PC-MRV) techniques, and demonstrated that the flow velocity increased in the cortical vein corresponding to the activated area during activation status. The increase of flow velocity was calculated to be about 20%. The reason for the increased flow velocity is probably due to the increased regional cerebral blood flow and volume in the activated area. We should be careful to analyze the data of the fMRI because the flow velocity affects the fMRI signal such as the inflow effect and the oblique flow effect. When using the gradient echo method, the effect of the flow velocity is one of the important factors of the fMRI signal. (author)

  6. Susceptibility-weighted MRI of extrapyramidal brain structures in Parkinsonian disorders

    Science.gov (United States)

    Schneider, Eva; Ng, Kia-Min; Yeoh, Chooi-Sum; Rumpel, Helmut; Fook-Chong, Stephanie; Li, Hui-Hua; Tan, Eng-King; Chan, Ling-Ling

    2016-01-01

    Abstract Susceptibility-weighted MRI (SWI) is sensitive to T2∗ effects and mineralization. We investigated differences in the extrapyramidal brain structures on SWI between Parkinson disease (PD) and postural instability gait disorder (PIGD) patients and correlated the SWI values with the degree of gait dysfunction. Forty patients diagnosed with PD and PIGD underwent 3 Tesla magnetic resonance imaging (MRI) brain study. An SWI sequence (TE/TR/FA 20/33/15) was used. Ten regions of interest were placed in the midbrain and basal ganglia by 2 independent raters blinded to subject data and quantitatively evaluated. The inter-rater reliability between the raters was excellent (interclass correlation coefficient >0.8). The SWI intensity values in all regions were on average lower in PIGD than in PD patients, with the lowest results found in globus pallidus. Multivariate analysis showed a lower SWI hypointensity in the putamen and globus pallidus in PIGD compared with PD patients, with a similar trend for the other basal ganglia nuclei. Pearson correlation analysis showed a statistically significant positive correlation between SWI putaminal hypointensity and the Tinetti total score (r = 0.39, P = 0.01) in both PD and PIGD. SWI putaminal hypointensity may be a useful imaging marker in prospective evaluation for clinical progression for Parkinsonian disorders. PMID:27367979

  7. Gender and age effects in structural brain asymmetry as measured by MRI texture analysis.

    Science.gov (United States)

    Kovalev, Vassili A; Kruggel, Frithjof; von Cramon, D Yves

    2003-07-01

    Effects of gender and age on structural brain asymmetry were studied by 3D texture analysis in 380 adults. Asymmetry is detected by comparing the complex 3D gray-scale image patterns in the left and right cerebral hemispheres as revealed by anatomical T1-weighted MRI datasets. The Talairach and Tournoux parcellation system was applied to study the asymmetry on five levels: the whole cerebrum, nine coronal sections, 12 axial sections, boxes resulting from both coronal and axial subdivisions, and by a sliding spherical window of 9 mm diameter. The analysis revealed that the brain asymmetry increases in the anterior-posterior direction starting from the central region onward. Male brains were found to be more asymmetric than female. This gender-related effect is noticeable in all brain areas but is most significant in the superior temporal gyrus, Heschl's gyrus, the adjacent white matter regions in the temporal stem and the knee of the optic radiation, the thalamus, and the posterior cingulate. The brain asymmetry increases significantly with age in the inferior frontal gyrus, anterior insula, anterior cingulate, parahippocampal gyrus, retrosplenial cortex, coronal radiata, and knee region of the internal capsule. Asymmetry decreases with age in the optic radiation, precentral gyrus, and angular gyrus. The texture-based method reported here is based on extended multisort cooccurrence matrices that employ intensity, gradient, and anisotropy features in a uniform way. It is sensitive, simple to reproduce, robust, and unbiased in the sense that segmentation of brain compartments and spatial transformations are not necessary. Thus, it should be considered as another tool for digital morphometry in neuroscience.

  8. 触觉刺激三叉神经上颌支面部支配区的功能性MRI研究%Brain Activity and Facial Tactile in Trigeminal Maxillary Division: An Functional MRI Study

    Institute of Scientific and Technical Information of China (English)

    李家; 刘洪臣; 李科; 金真; 朱霞

    2013-01-01

    Objective: To evaluate the brain cortical response to facial tactile in maxillary trigeminal division. Methods; 8 healthy volunteers participated in the study. Cotton-tipped swab stimuli was applied to right side of face in maxillary trigeminal division, and block designed BOLD functional MRI scan covering the whole brain was carried out. Results: Increased BOLD signals during tactile stimulation were found in left SI (BA3), insula/SII, Brodman's area 22,45, and right Brodman's area 40,9,38,41. Conclusion:Tactile stimuli activated contralateral primary, secondary somatosensory cortex, superior temporal gyrus, ipsilateral postcentral gyrus , inferior temporal gyrus, transverse temporal gyrus, bilateral prefrontal cortex .%目的:观察触觉刺激三叉神经上颌支(简称V2)面部支配区引起的大脑中枢反应区.方法:选取8名健康志愿者.用棉签刺激右侧面部三叉神经上颌支的支配区,采用触觉刺激减静息的组块设计方法,采集全脑血氧水平依赖对比的功能性MRI扫描数据.结果:脑激活区为左侧初级躯体感觉皮质(BA3)、岛叶/SII、BA22、BA45,右侧BA40、BA9 、BA38 、BA41.结论:对侧初级躯体感觉皮质、岛叶/SII和颞上回,同侧中央后回、颞下回和颞横回及双侧前额皮质是面部V2区触觉刺激激活的脑部功能区.

  9. Altered pattern of spontaneous brain activity in the patients with end-stage renal disease: a resting-state functional MRI study with regional homogeneity analysis.

    Directory of Open Access Journals (Sweden)

    Xue Liang

    Full Text Available PURPOSE: To investigate the pattern of spontaneous neural activity in patients with end-stage renal disease (ESRD with and without neurocognitive dysfunction using resting-state functional magnetic resonance imaging (rs-fMRI with a regional homogeneity (ReHo algorithm. MATERIALS AND METHODS: rs-fMRI data were acquired in 36 ESRD patients (minimal nephro-encephalopathy [MNE], n = 19, 13 male, 37±12.07 years; non-nephro-encephalopathy [non-NE], n = 17, 11 male, 38±12.13 years and 20 healthy controls (13 male, 7 female, 36±10.27 years. Neuropsychological (number connection test type A [NCT-A], digit symbol test [DST] and laboratory tests were performed in all patients. The Kendall's coefficient of concordance (KCC was used to measure the regional homogeneity for each subject. The regional homogeneity maps were compared using ANOVA tests among MNE, non-NE, and healthy control groups and post hoc t -tests between each pair in a voxel-wise way. A multiple regression analysis was performed to evaluate the relationships between ReHo index and NCT-A, DST scores, serum creatinine and urea levels, disease and dialysis duration. RESULTS: Compared with healthy controls, both MNE and non-NE patients showed decreased ReHo in the multiple areas of bilateral frontal, parietal and temporal lobes. Compared with the non-NE, MNE patients showed decreased ReHo in the right inferior parietal lobe (IPL, medial frontal cortex (MFC and left precuneus (PCu. The NCT-A scores and serum urea levels of ESRD patients negatively correlated with ReHo values in the frontal and parietal lobes, while DST scores positively correlated with ReHo values in the bilateral PCC/precuneus, MFC and inferior parietal lobe (IPL (all P0.05, AlphaSim corrected. CONCLUSION: Diffused decreased ReHo values were found in both MNE and non-NE patients. The progressively decreased ReHo in the default mode network (DMN, frontal and parietal lobes might be trait-related in MNE. The Re

  10. Combining fMRI and SNP Data to Investigate Connections Between Brain Function and Genetics Using Parallel ICA

    Science.gov (United States)

    Liu, Jingyu; Pearlson, Godfrey; Windemuth, Andreas; Ruano, Gualberto; Perrone-Bizzozero, Nora I.; Calhoun, Vince

    2009-01-01

    There is current interest in understanding genetic influences on both healthy and disordered brain function. We assessed brain function with functional magnetic resonance imaging (fMRI) data collected during an auditory oddball task—detecting an infrequent sound within a series of frequent sounds. Then, task-related imaging findings were utilized as potential intermediate phenotypes (endophenotypes) to investigate genomic factors derived from a single nucleotide polymorphism (SNP) array. Our target is the linkage of these genomic factors to normal/abnormal brain functionality. We explored parallel independent component analysis (paraICA) as a new method for analyzing multimodal data. The method was aimed to identify simultaneously independent components of each modality and the relationships between them. When 43 healthy controls and 20 schizophrenia patients, all Caucasian, were studied, we found a correlation of 0.38 between one fMRI component and one SNP component. This fMRI component consisted mainly of parietal lobe activations. The relevant SNP component was contributed to significantly by 10 SNPs located in genes, including those coding for the nicotinic α-7cholinergic receptor, aromatic amino acid decarboxylase, disrupted in schizophrenia 1, among others. Both fMRI and SNP components showed significant differences in loading parameters between the schizophrenia and control groups (P = 0.0006 for the fMRI component; P = 0.001 for the SNP component). In summary, we constructed a framework to identify interactions between brain functional and genetic information; our findings provide a proof-of-concept that genomic SNP factors can be investigated by using endophenotypic imaging findings in a multivariate format. PMID:18072279

  11. Is family special to the brain? An event-related fMRI study of familiar, familial, and self-face recognition.

    Science.gov (United States)

    Platek, Steven M; Kemp, Shelly M

    2009-02-01

    The face-processing network has evolved to respond differentially to different classes of faces depending on their relevance to the perceiver. For example, self-, familiar, and unknown faces are associated with activation in different neural substrates. Family should represent a special class of face stimuli that is of high relevance to individuals, because incorrect assignment of kinship can have dire consequences (e.g., incest, cuckoldry). Therefore evolution should have favored redundant mechanisms for detection of kin. We used fMRI to investigate the neural substrates associated with viewing faces of kin compared to other classes of faces (e.g., self-face, familiar face, and unknown face), and to examine the degree to which self-facial resemblance activated similar neural substrates. Contrasting kin faces with unknown faces activated substrates associated with self-face recognition, while comparing kin faces to friend faces activated posterior cingulate and cuneus. Similar posterior medial substrates were recruited when contrasting self-resembling faces with morphed faces of kin, suggesting these regions potentially represent computational processing about facial familiarity and identity. On the other hand, discrimination of self-resembling faces from familiar morphs activated anterior medial substrates (anterior cingulate cortex, ACC, medial prefrontal cortex, MPFC). These findings, and a region of interest (ROI) analysis, highlight the role of the extended face-processing network for discrimination of kin from familiar non-kin members of one's social group based on self-referent phenotypic cues.

  12. Brain Perfusion MRI Findings in Patients with Behcet’s Disease

    Directory of Open Access Journals (Sweden)

    Alpay Alkan

    2012-01-01

    Full Text Available Objective. To search brain perfusion MRI (pMRI changes in Behcet’s disease (BD with or without neurological involvement. Materials and Method. The pMRI were performed in 34 patients with BD and 16 healthy controls. Based on neurologic examination and post-contrast MRI, 12 patients were classified as Neuro-Behcet (group 1, NBD and 22 patients as BD without neurological involvement (group 2. Mean transit time (MTT, time to peak (TTP, relative cerebral blood volume (rCBV, and relative cerebral blood flow (rCBF were obtained and compared to those of healthy control group (group 3. Results. There was a significant difference in the MTT and rCBF within the pons and parietal cortex in groups 1 and 2. rCBV increased in cerebral pedicle in group 1 compared with groups 2 and 3. In the temporal lobe white matter, prolonged MTT and decreased rCBF were found in groups 1 and 2. In the corpus striatum, internal capsule, and periventricular white matter, rCBF increased in group 1 compared with group 3 and decreased in groups 1 and 2. Conclusion. Brain pMRI is a very sensitive method to detect brain involvement in patients with BD and aids the clinical diagnosis of NBD, especially in patients with negative MRI findings.

  13. Simultaneous fMRI-PET of the opioidergic pain system in human brain

    DEFF Research Database (Denmark)

    Wey, Hsiao-Ying; Catana, Ciprian; Hooker, Jacob M;

    2014-01-01

    distinct components of the blood oxygenation level dependent (BOLD) fMRI signal has not yet been shown. We obtained sixteen fMRI-PET data sets from eight healthy volunteers. Each subject participated in randomized order in a pain scan and a control (nonpainful pressure) scan on the same day. Dynamic PET...... in this region. Simultaneous fMRI-PET provides unique opportunities allowing us to relate specific neurochemical events to functional hemodynamic activation and to investigate the impacts of neurotransmission on neurovascular coupling of the human brain in vivo....

  14. Neonatal brain MRI: how reliable is the radiologist's eye?

    Energy Technology Data Exchange (ETDEWEB)

    Morel, B. [A. Trousseau Hospital APHP, Pediatric Radiology, Paris (France); LTCI, CNRS, Telecom ParisTech, Universite Paris-Saclay, Paris (France); Antoni, G.; Teglas, J.P. [INSERM, CESP Centre for Research in Epidemiology and Population Health, U1018, Reproduction and Child Development, Villejuif (France); Bloch, I. [LTCI, CNRS, Telecom ParisTech, Universite Paris-Saclay, Paris (France); Adamsbaum, C. [Paris Sud University, Pediatric Radiology Department Bicetre Hospital APHP, Faculty of Medicine, Paris (France)

    2016-02-15

    White matter (WM) analysis in neonatal brain magnetic resonance imaging (MRI) is challenging, as demonstrated by the issue of diffuse excessive high signal intensity (DEHSI). We evaluated the reliability of the radiologist's eye in this context. Three experienced observers graded the WM signal intensity on axial T2-weighted 1.5T images from 60 different premature newborns on 2 occasions 4 weeks apart with a semi-quantitative classification under identical viewing conditions. The intra- and inter-observer correlation coefficients were fair to moderate (Fleiss' kappa between 0.21 and 0.60). This is a serious limitation of which we need to be aware, as it can lead to contradictory conclusions in the challenging context of term-equivalent age brain MRI in premature infants. These results highlight the need for a semiautomatic tool to help in objectively analyzing MRI signal intensity in the neonatal brain. (orig.)

  15. [Complex partial status epilepticus with recurrent episodes of complex visual hallucinations: study by using 123I-IMP-SPECT, brain MRI and EEG].

    Science.gov (United States)

    Sakai, Toshiyuki; Kondo, Masahide; Tomimoto, Hidekazu

    2015-01-01

    We report a 72-year-old woman with complex partial status epilepticus who showed recurrent episodes of complex visual hallucinations (CVH). Brain diffusion-weighted magnetic resonance images revealed gyriform cortical hyperintensity in the right parietal, occipital and temporal lobes, and brain magnetic resonance angiograhy revealed a hyperintensity in the right dilated middle cerebral artery during ictal period. Ictal N-isopropyl-p-(iodine-123)-iodoamphetamine single photon emission computed tomography (123I-IMP-SPECT) with three-dimensional stereotactic surface projection (3D-SSP) 14 days after the onset of the first CVH revealed hyperperfusion in the right latero-inferior occipito-temporal region with relation to motion. CVH spontaneously subsided 17 days after the onset of the first CVH. CVH recurred one year after the first CVH. Ictal 123I-IMP-SPECT with 3D-SSP revealed marked hyperperfusion in the right lateral parietal region probably with relation to face and figure hallucinations. Ictal scalp EEGs revealed rhythmic polyspikes at 12 Hz with high amplitude (100-200 μV) in bilateral posterior occipital and temporal region with the right side dominance for 20 seconds and more in several occasions. Interictal 123I-IMP-SPECT with 3D-SSP 28 days after recurrence of CVH revealed marked hypoperfusion in the right lateral parietal region, and recovery of hypoperfusion in the right latero-inferior occipito-temporal region. These findings suggest that ictal CVH might be induced by the spread of epileptic discharges from the right parieto-occipito-temporal region with the old brain contusion (epileptogenic region) to the right latero-inferior occipito-temporal region and the right lateral parietal region (symptomatogenic regions).

  16. Brain-wide pathway for waste clearance captured by contrast-enhanced MRI.

    Science.gov (United States)

    Iliff, Jeffrey J; Lee, Hedok; Yu, Mei; Feng, Tian; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

    2013-03-01

    The glymphatic system is a recently defined brain-wide paravascular pathway for cerebrospinal fluid (CSF) and interstitial fluid (ISF) exchange that facilitates efficient clearance of solutes and waste from the brain. CSF enters the brain along para-arterial channels to exchange with ISF, which is in turn cleared from the brain along para-venous pathways. Because soluble amyloid β clearance depends on glymphatic pathway function, we proposed that failure of this clearance system contributes to amyloid plaque deposition and Alzheimer's disease progression. Here we provide proof of concept that glymphatic pathway function can be measured using a clinically relevant imaging technique. Dynamic contrast-enhanced MRI was used to visualize CSF-ISF exchange across the rat brain following intrathecal paramagnetic contrast agent administration. Key features of glymphatic pathway function were confirmed, including visualization of para-arterial CSF influx and molecular size-dependent CSF-ISF exchange. Whole-brain imaging allowed the identification of two key influx nodes at the pituitary and pineal gland recesses, while dynamic MRI permitted the definition of simple kinetic parameters to characterize glymphatic CSF-ISF exchange and solute clearance from the brain. We propose that this MRI approach may provide the basis for a wholly new strategy to evaluate Alzheimer's disease susceptibility and progression in the live human brain.

  17. Pain facilitation brain regions activated by nalbuphine are revealed by pharmacological fMRI.

    Directory of Open Access Journals (Sweden)

    Robert Gear

    Full Text Available Nalbuphine, an agonist-antagonist kappa-opioid, produces brief analgesia followed by enhanced pain/hyperalgesia in male postsurgical patients. However, it produces profound analgesia without pain enhancement when co-administration with low dose naloxone. To examine the effect of nalbuphine or nalbuphine plus naloxone on activity in brain regions that may explain these differences, we employed pharmacological magnetic resonance imaging (phMRI in a double blind cross-over study with 13 healthy male volunteers. In separate imaging sessions subjects were administered nalbuphine (5 mg/70 kg preceded by either saline (Sal-Nalb or naloxone 0.4 mg (Nalox-Nalb. Blood oxygen level-dependent (BOLD activation maps followed by contrast and connectivity analyses revealed marked differences. Sal-Nalb produced significantly increased activity in 60 brain regions and decreased activity in 9; in contrast, Nalox-Nalb activated only 14 regions and deactivated only 3. Nalbuphine, like morphine in a previous study, attenuated activity in the inferior orbital cortex, and, like noxious stimulation, increased activity in temporal cortex, insula, pulvinar, caudate, and pons. Co-administration/pretreatment of naloxone selectively blocked activity in pulvinar, pons and posterior insula. Nalbuphine induced functional connectivity between caudate and regions in the frontal, occipital, temporal, insular, middle cingulate cortices, and putamen; naloxone co-admistration reduced all connectivity to non-significant levels, and, like phMRI measures of morphine, increased activation in other areas (e.g., putamen. Naloxone pretreatment to nalbuphine produced changes in brain activity possess characteristics of both analgesia and algesia; naloxone selectively blocks activity in areas associated with algesia. Given these findings, we suggest that nalbuphine interacts with a pain salience system, which can modulate perceived pain intensity.

  18. Abnormal Brain Areas Common to the Focal Epilepsies: Multivariate Pattern Analysis of fMRI.

    Science.gov (United States)

    Pedersen, Mangor; Curwood, Evan K; Vaughan, David N; Omidvarnia, Amir H; Jackson, Graeme D

    2016-04-01

    Individuals with focal epilepsy have heterogeneous sites of seizure origin. However, there may be brain regions that are common to most cases of intractable focal epilepsy. In this study, we aim to identify these using multivariate analysis of task-free functional MRI. Fourteen subjects with extratemporal focal epilepsy and 14 healthy controls were included in the study. Task-free functional MRI data were used to calculate voxel-wise regional connectivity with regional homogeneity (ReHo) and weighted degree centrality (DCw), in addition to regional activity using fraction of amplitude of low-frequency fluctuations (fALFF). Multivariate pattern analysis was applied to each of these metrics to discriminate brain areas that differed between focal epilepsy subjects and healthy controls. ReHo and DCw classified focal epilepsy subjects from healthy controls with high accuracy (89.3% and 75%, respectively). However, fALFF did not significantly classify patients from controls. Increased regional network activity in epilepsy subjects was seen in the ipsilateral piriform cortex, insula, and thalamus, in addition to the dorsal anterior cingulate cortex and lateral frontal cortices. Decreased regional connectivity was observed in the ventromedial prefrontal cortex, as well as lateral temporal cortices. Patients with extratemporal focal epilepsy have common areas of abnormality (ReHo and DCw measures), including the ipsilateral piriform cortex, temporal neocortex, and ventromedial prefrontal cortex. ReHo shows additional increase in the "salience network" that includes anterior insula and anterior cingulate cortex. DCw showed additional effects in the ipsilateral thalamus and striatum. These brain areas may represent key regional network properties underlying focal epilepsy.

  19. Altered Brain Functional Activity in Infants with Congenital Bilateral Severe Sensorineural Hearing Loss: A Resting-State Functional MRI Study under Sedation

    Science.gov (United States)

    Che, Jing; Li, Qiang; Chai, Chao; Zheng, Meizhu; Shen, Wen

    2017-01-01

    Early hearing deprivation could affect the development of auditory, language, and vision ability. Insufficient or no stimulation of the auditory cortex during the sensitive periods of plasticity could affect the function of hearing, language, and vision development. Twenty-three infants with congenital severe sensorineural hearing loss (CSSHL) and 17 age and sex matched normal hearing subjects were recruited. The amplitude of low frequency fluctuations (ALFF) and regional homogeneity (ReHo) of the auditory, language, and vision related brain areas were compared between deaf infants and normal subjects. Compared with normal hearing subjects, decreased ALFF and ReHo were observed in auditory and language-related cortex. Increased ALFF and ReHo were observed in vision related cortex, which suggest that hearing and language function were impaired and vision function was enhanced due to the loss of hearing. ALFF of left Brodmann area 45 (BA45) was negatively correlated with deaf duration in infants with CSSHL. ALFF of right BA39 was positively correlated with deaf duration in infants with CSSHL. In conclusion, ALFF and ReHo can reflect the abnormal brain function in language, auditory, and visual information processing in infants with CSSHL. This demonstrates that the development of auditory, language, and vision processing function has been affected by congenital severe sensorineural hearing loss before 4 years of age.

  20. Altered Brain Functional Activity in Infants with Congenital Bilateral Severe Sensorineural Hearing Loss: A Resting-State Functional MRI Study under Sedation

    Directory of Open Access Journals (Sweden)

    Shuang Xia

    2017-01-01

    Full Text Available Early hearing deprivation could affect the development of auditory, language, and vision ability. Insufficient or no stimulation of the auditory cortex during the sensitive periods of plasticity could affect the function of hearing, language, and vision development. Twenty-three infants with congenital severe sensorineural hearing loss (CSSHL and 17 age and sex matched normal hearing subjects were recruited. The amplitude of low frequency fluctuations (ALFF and regional homogeneity (ReHo of the auditory, language, and vision related brain areas were compared between deaf infants and normal subjects. Compared with normal hearing subjects, decreased ALFF and ReHo were observed in auditory and language-related cortex. Increased ALFF and ReHo were observed in vision related cortex, which suggest that hearing and language function were impaired and vision function was enhanced due to the loss of hearing. ALFF of left Brodmann area 45 (BA45 was negatively correlated with deaf duration in infants with CSSHL. ALFF of right BA39 was positively correlated with deaf duration in infants with CSSHL. In conclusion, ALFF and ReHo can reflect the abnormal brain function in language, auditory, and visual information processing in infants with CSSHL. This demonstrates that the development of auditory, language, and vision processing function has been affected by congenital severe sensorineural hearing loss before 4 years of age.

  1. Evaluation of 2D multiband EPI imaging for high-resolution, whole-brain, task-based fMRI studies at 3T: Sensitivity and slice leakage artifacts.

    Science.gov (United States)

    Todd, Nick; Moeller, Steen; Auerbach, Edward J; Yacoub, Essa; Flandin, Guillaume; Weiskopf, Nikolaus

    2016-01-01

    Functional magnetic resonance imaging (fMRI) studies that require high-resolution whole-brain coverage have long scan times that are primarily driven by the large number of thin slices acquired. Two-dimensional multiband echo-planar imaging (EPI) sequences accelerate the data acquisition along the slice direction and therefore represent an attractive approach to such studies by improving the temporal resolution without sacrificing spatial resolution. In this work, a 2D multiband EPI sequence was optimized for 1.5mm isotropic whole-brain acquisitions at 3T with 10 healthy volunteers imaged while performing simultaneous visual and motor tasks. The performance of the sequence was evaluated in terms of BOLD sensitivity and false-positive activation at multiband (MB) factors of 1, 2, 4, and 6, combined with in-plane GRAPPA acceleration of 2× (GRAPPA 2), and the two reconstruction approaches of Slice-GRAPPA and Split Slice-GRAPPA. Sensitivity results demonstrate significant gains in temporal signal-to-noise ratio (tSNR) and t-score statistics for MB 2, 4, and 6 compared to MB 1. The MB factor for optimal sensitivity varied depending on anatomical location and reconstruction method. When using Slice-GRAPPA reconstruction, evidence of false-positive activation due to signal leakage between simultaneously excited slices was seen in one instance, 35 instances, and 70 instances over the ten volunteers for the respective accelerations of MB 2×GRAPPA 2, MB 4×GRAPPA 2, and MB 6×GRAPPA 2. The use of Split Slice-GRAPPA reconstruction suppressed the prevalence of false positives significantly, to 1 instance, 5 instances, and 5 instances for the same respective acceleration factors. Imaging protocols using an acceleration factor of MB 2×GRAPPA 2 can be confidently used for high-resolution whole-brain imaging to improve BOLD sensitivity with very low probability for false-positive activation due to slice leakage. Imaging protocols using higher acceleration factors (MB 3 or MB 4

  2. MRI of the brain and craniocervical junction in Morquio`s disease

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, D.G. [Department of Radiology, Hope Hospital, Stott Lane, Salford, Manchester M6 8HD (United Kingdom); Chadderton, R.D. [Department of Neurosurgery, Hope Hospital, Salford, Manchester M6 8HD (United Kingdom); Cowie, R.A. [Department of Neurosurgery, Hope Hospital, Salford, Manchester M6 8HD (United Kingdom); Wraith, J.E. [Willink Biochemical Genetics Unit, Royal Manchester Children`s Hospital, Manchester M27 4HA (United Kingdom); Jenkins, J.P.R. [Department of Clinical Radiology, Manchester Royal Infirmary, Oxford Road, Manchester (United Kingdom)

    1997-05-01

    We reviewed MRI of the brain and cervical spine in 11 patients with Morquio`s disease. No abnormality was seen in the brain. The odontoid peg was abnormal in all patients, with varying degrees of cord compression due to an anterior soft tissue mass and indentation by the posterior arch of the atlas. The degree of cord compression was more marked than suggested by the symptoms and signs. We recommend MRI of the cervical spine in children with Morquio`s disease before the development of neurological symptoms, to optimise the timing and type of surgical intervention. (orig.). With 5 figs., 2 tabs.

  3. Toward brain correlates of natural behavior: fMRI during violent video games.

    Science.gov (United States)

    Mathiak, Klaus; Weber, René

    2006-12-01

    Modern video games represent highly advanced virtual reality simulations and often contain virtual violence. In a significant amount of young males, playing video games is a quotidian activity, making it an almost natural behavior. Recordings of brain activation with functional magnetic resonance imaging (fMRI) during gameplay may reflect neuronal correlates of real-life behavior. We recorded 13 experienced gamers (18-26 years; average 14 hrs/week playing) while playing a violent first-person shooter game (a violent computer game played in self-perspective) by means of distortion and dephasing reduced fMRI (3 T; single-shot triple-echo echo-planar imaging [EPI]). Content analysis of the video and sound with 100 ms time resolution achieved relevant behavioral variables. These variables explained significant signal variance across large distributed networks. Occurrence of violent scenes revealed significant neuronal correlates in an event-related design. Activation of dorsal and deactivation of rostral anterior cingulate and amygdala characterized the mid-frontal pattern related to virtual violence. Statistics and effect sizes can be considered large at these areas. Optimized imaging strategies allowed for single-subject and for single-trial analysis with good image quality at basal brain structures. We propose that virtual environments can be used to study neuronal processes involved in semi-naturalistic behavior as determined by content analysis. Importantly, the activation pattern reflects brain-environment interactions rather than stimulus responses as observed in classical experimental designs. We relate our findings to the general discussion on social effects of playing first-person shooter games.

  4. Potential brain language reorganization in a boy with refractory epilepsy; an fNIRS–EEG and fMRI comparison

    Directory of Open Access Journals (Sweden)

    Phetsamone Vannasing

    2016-01-01

    Full Text Available As part of a presurgical investigation for a resection of a tumor located in the left temporal brain region, we evaluated pre- and postsurgical language lateralization in a right-handed boy with refractory epilepsy. In this study, we compared functional near infrared spectroscopy (fNIRS results obtained while the participant performed expressive and receptive language tasks with those obtained using functional magnetic resonance imaging (fMRI. This case study illustrates the potential for NIRS to contribute favorably to the localization of language functions in children with epilepsy and cognitive or behavioral problems and its potential advantages over fMRI in presurgical assessment. Moreover, it suggests that fNIRS is sensitive in localizing an atypical language network or potential brain reorganization related to epilepsy in young patients.

  5. Age-specific MRI brain and head templates for healthy adults from twenty through eighty-nine years of age

    Directory of Open Access Journals (Sweden)

    Paul T Fillmore

    2015-04-01

    Full Text Available This study created and tested a database of adult, age-specific MRI brain and head templates. The participants included healthy adults from 20 through 89 years of age. The templates were done in 5-year, 10-year, and multi-year intervals from 20 through 89 years, and consist of average T1W for the head and brain, and segmenting priors for GM, WM, and CSF. It was found that age-appropriate templates provided less biased tissue classification estimates than age-inappropriate reference data and reference data based on young adult templates. This database is available for use by other investigators and clinicians for their MRI studies, as well as other types of neuroimaging and electrophysiological research (http://jerlab.psych.sc.edu/NeurodevelopmentalMRIDatabase/.

  6. Multi-atlas multi-shape segmentation of fetal brain MRI for volumetric and morphometric analysis of ventriculomegaly.

    Science.gov (United States)

    Gholipour, Ali; Akhondi-Asl, Alireza; Estroff, Judy A; Warfield, Simon K

    2012-04-15

    The recent development of motion robust super-resolution fetal brain MRI holds out the potential for dramatic new advances in volumetric and morphometric analysis. Volumetric analysis based on volumetric and morphometric biomarkers of the developing fetal brain must include segmentation. Automatic segmentation of fetal brain MRI is challenging, however, due to the highly variable size and shape of the developing brain; possible structural abnormalities; and the relatively poor resolution of fetal MRI scans. To overcome these limitations, we present a novel, constrained, multi-atlas, multi-shape automatic segmentation method that specifically addresses the challenge of segmenting multiple structures with similar intensity values in subjects with strong anatomic variability. Accordingly, we have applied this method to shape segmentation of normal, dilated, or fused lateral ventricles for quantitative analysis of ventriculomegaly (VM), which is a pivotal finding in the earliest stages of fetal brain development, and warrants further investigation. Utilizing these innovative techniques, we introduce novel volumetric and morphometric biomarkers of VM comparing these values to those that are generated by standard methods of VM analysis, i.e., by measuring the ventricular atrial diameter (AD) on manually selected sections of 2D ultrasound or 2D MRI. To this end, we studied 25 normal and abnormal fetuses in the gestation age (GA) range of 19 to 39 weeks (mean=28.26, stdev=6.56). This heterogeneous dataset was essentially used to 1) validate our segmentation method for normal and abnormal ventricles; and 2) show that the proposed biomarkers may provide improved detection of VM as compared to the AD measurement.

  7. Neonatal Neurobehavior and Diffusion MRI Changes in Brain Reorganization Due to Intrauterine Growth Restriction in a Rabbit Model

    Science.gov (United States)

    Eixarch, Elisenda; Batalle, Dafnis; Illa, Miriam; Muñoz-Moreno, Emma; Arbat-Plana, Ariadna; Amat-Roldan, Ivan; Figueras, Francesc; Gratacos, Eduard

    2012-01-01

    Background Intrauterine growth restriction (IUGR) affects 5–10% of all newborns and is associated with a high risk of abnormal neurodevelopment. The timing and patterns of brain reorganization underlying IUGR are poorly documented. We developed a rabbit model of IUGR allowing neonatal neurobehavioral assessment and high resolution brain diffusion magnetic resonance imaging (MRI). The aim of the study was to describe the pattern and functional correlates of fetal brain reorganization induced by IUGR. Methodology/Principal Findings IUGR was induced in 10 New Zealand fetal rabbits by ligation of 40–50% of uteroplacental vessels in one horn at 25 days of gestation. Ten contralateral horn fetuses were used as controls. Cesarean section was performed at 30 days (term 31 days). At postnatal day +1, neonates were assessed by validated neurobehavioral tests including evaluation of tone, spontaneous locomotion, reflex motor activity, motor responses to olfactory stimuli, and coordination of suck and swallow. Subsequently, brains were collected and fixed and MRI was performed using a high resolution acquisition scheme. Global and regional (manual delineation and voxel based analysis) diffusion tensor imaging parameters were analyzed. IUGR was associated with significantly poorer neurobehavioral performance in most domains. Voxel based analysis revealed fractional anisotropy (FA) differences in multiple brain regions of gray and white matter, including frontal, insular, occipital and temporal cortex, hippocampus, putamen, thalamus, claustrum, medial septal nucleus, anterior commissure, internal capsule, fimbria of hippocampus, medial lemniscus and olfactory tract. Regional FA changes were correlated with poorer outcome in neurobehavioral tests. Conclusions IUGR is associated with a complex pattern of brain reorganization already at birth, which may open opportunities for early intervention. Diffusion MRI can offer suitable imaging biomarkers to characterize and monitor

  8. Brain herniations into the dural venous sinus or calvarium: MRI findings, possible causes and clinical significance

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    Battal, Bilal; Hamcan, Salih; Akgun, Veysel; Sari, Sebahattin; Tasar, Mustafa [Gulhane Military Medical School, Department of Radiology, Ankara (Turkey); Oz, Oguzhan [Gulhane Military Medical School, Department of Neurology, Ankara (Turkey);