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Sample records for brain mri study

  1. Study on MRI findings in postresuscitation brains

    International Nuclear Information System (INIS)

    We evaluated chronological changes in T1/T2-weighted and diffusion-weighted magnetic resonance imaging (MRI) findings in patients with global cerebral ischemia compared to computed tomography (CT) and single photon emission computed tomography (SPECT) to determine the advantages this presents in determining a patient's prognosis. We retrospectively studied MRI in 28 patients resuscitated after cardiopulmonary arrest. Patients were divided by outcome into 4 groups -- good outcome in 5, moderate disability in 2, vegetative in 17, and 4 brain-dead. Those with good recovery had normal CT and MRI findings. Those with moderate disability demonstrated high signal intensity in basal ganglia and posterior cerebral cortex during the chronic period. All vegetative patients had abnormal CT findings and their T2-weighted images during the acute period demonstrated high signal intensity in the cerebral cortex and basal ganglia; T1-weighted image during the chronic period showed similar findings, while diffusion-weighted images indicated high signal intensity in the cerebral cortex from the very acute period, during which abnormal findings were seen in the cortex, putamen, and thalamus more frequently than in T2-weighted images. Moreover, regional cerebral blood flow significantly decreased during the chronic period. All brain-dead patients had CT findings of diffuse cerebral edema and loss of density difference between gray and white matter. T2-weighted images respectively showed an extraordinary high density difference between gray and white matter and diffusion-weighted images high signal density in the whole brain. MRI detects chronologic changes in postresuscitation brain damage better than CT findings. Diffusion-weighted images identify hypoxic-ischemic lesions during the very acute period. MRI thus appears useful in evaluating patient prognosis and care. (author)

  2. Longitudinal MRI studies of brain morphometry

    DEFF Research Database (Denmark)

    Skimminge, Arnold Jesper Møller

    , putamen, inferior and superior longitudinal fasciculus, corpus callosum and corona radiata. This indicates that the long-term atrophy is attributable to consequences of traumatic axonal injury. Despite progressive atrophy, remarkable clinical improvement occurred in most patients. The other study utilized...

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

    International Nuclear Information System (INIS)

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  5. 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

  6. Brain Activity Associated with Emoticons: An fMRI Study

    Science.gov (United States)

    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.

  7. Low-field MRI for studies of human pulmonary physiology and traumatic brain injury

    Science.gov (United States)

    Wilson, Alyssa; Devience, Stephen; Rosen, Matthew; Walsworth, Ronald

    2011-05-01

    We describe recent progress on the development of an open-access low-magnetic-field MRI system for studies of human pulmonary physiology and traumatic brain injury. Low-field MRI benefits from reduced magnetic susceptibility effects and can provide high-resolution images of the human body when used with hyperpolarized media such as 3He and 129Xe.

  8. MRI brain imaging.

    Science.gov (United States)

    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.

  9. MRI as a tool to study brain structure from mouse models for mental retardation

    Science.gov (United States)

    Verhoye, Marleen; Sijbers, Jan; Kooy, R. F.; Reyniers, E.; Fransen, E.; Oostra, B. A.; Willems, Peter; Van der Linden, Anne-Marie

    1998-07-01

    Nowadays, transgenic mice are a common tool to study brain abnormalities in neurological disorders. These studies usually rely on neuropathological examinations, which have a number of drawbacks, including the risk of artefacts introduced by fixation and dehydration procedures. Here we present 3D Fast Spin Echo Magnetic Resonance Imaging (MRI) in combination with 2D and 3D segmentation techniques as a powerful tool to study brain anatomy. We set up MRI of the brain in mouse models for the fragile X syndrome (FMR1 knockout) and Corpus callosum hypoplasia, mental Retardation, Adducted thumbs, Spastic paraplegia and Hydrocephalus (CRASH) syndrome (L1CAM knockout). Our major goal was to determine qualitative and quantitative differences in specific brain structures. MRI of the brain of fragile X and CRASH patients has revealed alterations in the size of specific brain structures, including the cerebellar vermis and the ventricular system. In the present MRI study of the brain from fragile X knockout mice, we have measured the size of the brain, cerebellum and 4th ventricle, which were reported as abnormal in human fragile X patients, but found no evidence for altered brain regions in the mouse model. In CRASH syndrome, the most specific brain abnormalities are vermis hypoplasia and abnormalities of the ventricular system with some degree of hydrocephalus. With the MRI study of L1CAM knockout mice we found vermis hypoplasia, abnormalities of the ventricular system including dilatation of the lateral and the 4th ventricles. These subtle abnormalities were not detected upon standard neuropathological examination. Here we proved that this sensitive MRI technique allows to measure small differences which can not always be detected by means of pathology.

  10. Structural MRI studies of language function in the undamaged brain

    OpenAIRE

    Richardson, F. M.; Price, C.J.

    2009-01-01

    In recent years, the demonstration that structural changes can occur in the human brain beyond those associated with development, ageing and neuropathology has revealed a new approach to studying the neural basis of behaviour. In this review paper, we focus on structural imaging studies of language that have utilised behavioural measures in order to investigate the neural correlates of language skills in the undamaged brain. We report studies that have used two different techniques: voxel-bas...

  11. 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.

  12. 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

  13. Fetal Brain MRI

    Directory of Open Access Journals (Sweden)

    Ahmad Tahmasebpour

    2010-05-01

    Full Text Available MRI is a useful supplement to ultrasonography for the assessment of fetal brain malformations. Superior soft tissue contrast and the ability to depict sulcation and myelination are the strengths of MRI. Subtle or inconclusive ultrasonography abnormalities can be confirmed or ruled out by MRI. In some cases, additional findings detected with MRI often help in arriving at a definitive diagnosis, which is necessary for parental counseling and for guiding management. Fast T2W sequences form the basis of fetal MRI. There have been no reports of deleterious effects of MRI on the fetus. A few case examples are presented to illustrate the advantages of MRI. "nThe database comprises MR images of a total of 26 fetuses (gestational age 22-23 weeks reformed be-cause of suspected abnormalities due to ultrasonic findings, family history or maternal illness and scanned on a 1.5T MR system using single-shot fast spin echo "SSFSE, HASTE" T2 sequence, slice thick-ness 3mm, no gap. "HASTE=fourier acquisition single shotturbospinecho". In the normal fetus the ventricular size or volume did not vary with the gestational age but cerebral and cerebellar volumes increase during the same period "Grossman et al." Diagnostic accuracy is about 48%. "OB/GYN news, Chicago". Today it is not necessary to use sedatives or muscle relaxants to control fetal movement "ultra-fast MRI techniques". Modified technique for 50% reduction in the time necessary to take MRI images of the fetal brain is dedicated by Kianosh Hosseinzadeh, by using a line of reference through the eyes "AJR 2005"."nOur fetuses are 22-23 weeks in gestational age, 26 in number and we found agenesis of corpus callosum, hydrocephaly, holoprosencephaly, mega-cisterna magna, occipital meningocele, Arnold Chiari malformation type 1, Dandy Walker syndrome and lissencephaly

  14. Comparison of two brain tumor-localizing MRI agent. GD-BOPTA and GD-DTPA. MRI and ICP study of rat brain tumor model

    International Nuclear Information System (INIS)

    In this study, we compared the behavior of Gd-BOPTA as a brain tumor selective contrast agent with Gd-DTPA in a common dose of 0.1 mmol/kg. We performed a MRI study using those two agent as contrast material, and we measured tissue Gd-concentrations by ICP-AES. As a result, Gd-BOPTA showed a better MRI enhancement in brain tumor. ICP showed significantly greater uptake of Gd-BOPTA in tumor samples, at all time course peaked at 5 minutes after administration, Gd being retained for a longer time in brain tumor till 2 hours, without rapid elimination as Gd-DTPA. We conclude that Gd-BOPTA is a new useful contrast material for MR imaging in brain tumor and an effective absorption agent for neutron capture therapy for further research. (author)

  15. 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

  16. Longitudinal fMRI studies: Exploring brain plasticity and repair in MS.

    Science.gov (United States)

    Enzinger, Christian; Pinter, Daniela; Rocca, Maria A; De Luca, John; Sastre-Garriga, Jaume; Audoin, Bertrand; Filippi, Massimo

    2016-03-01

    Functional magnetic resonance imaging (fMRI) has greatly advanced our understanding of cerebral functional changes occurring in patients with multiple sclerosis (MS). However, most of our knowledge regarding brain plasticity and repair in MS as evidenced by fMRI has been extrapolated from cross-sectional studies across different phenotypes of the disease. This topical review provides an overview of this research, but also highlights limitations of existing fMRI studies with cross-sectional design. We then review the few existing longitudinal fMRI studies and discuss the feasibility and constraints of serial fMRI in individuals with MS. We further emphasize the potential to track fMRI changes in evolving disease and the insights this may give in terms of mechanisms of adaptation and repair, focusing on serial fMRI to monitor response to disease-modifying therapies or rehabilitation interventions. Finally, we offer recommendations for designing future research studies to overcome previous methodological shortcomings. PMID:26683590

  17. Brain MRI of diabetes Mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Yutaka; Tanaka, Hisashi; Ohtani, Masatoshi; Yamamoto, Hiroshi; Yamamoto, Tadashi; Tsukaguchi, Isao (Osaka Rosai Hospital, Sakai (Japan))

    1993-11-01

    One hundred and fifty-nine patients with diabetes mellitus (DM) and 2,566 patients without DM were studied on brain MRI. The results taught us that the incidence of cerebral atrophy was significantly higher in DM patients than in controls. Unexpectedly, the incidence of cerebral infarction showed no significant difference between the two groups. (author).

  18. Brain MRI of diabetes Mellitus

    International Nuclear Information System (INIS)

    One hundred and fifty-nine patients with diabetes mellitus (DM) and 2,566 patients without DM were studied on brain MRI. The results taught us that the incidence of cerebral atrophy was significantly higher in DM patients than in controls. Unexpectedly, the incidence of cerebral infarction showed no significant difference between the two groups. (author)

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    International Nuclear Information System (INIS)

    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 (SGAa) and 3) small for GA at birth with failure of catch-up growth at the time of MRI (SGAb). 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 SGAb 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.)

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

    International Nuclear Information System (INIS)

    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)

  4. 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).

  5. Rehabilitative Interventions and Brain Plasticity in Autism Spectrum Disorders: Focus on MRI-Based Studies.

    Science.gov (United States)

    Calderoni, Sara; Billeci, Lucia; Narzisi, Antonio; Brambilla, Paolo; Retico, Alessandra; Muratori, Filippo

    2016-01-01

    Clinical and research evidence supports the efficacy of rehabilitative intervention for improving targeted skills or global outcomes in individuals with autism spectrum disorder (ASD). However, putative mechanisms of structural and functional brain changes are poorly understood. This review aims to investigate the research literature on the neural circuit modifications after non-pharmacological intervention. For this purpose, longitudinal studies that used magnetic resonance imaging (MRI)-based techniques at the start and at the end of the trial to evaluate the neural effects of rehabilitative treatment in subjects with ASD were identified. The six included studies involved a limited number of patients in the active group (from 2 to 16), and differed by acquisition method (task-related and resting-state functional MRI) as well as by functional MRI tasks. Overall, the results produced by the selected investigations demonstrated brain plasticity during the treatment interval that results in an activation/functional connectivity more similar to those of subjects with typical development (TD). Repeated MRI evaluation may represent a promising tool for the detection of neural changes in response to treatment in patients with ASD. However, large-scale randomized controlled trials after standardized rehabilitative intervention are required before translating these preliminary results into clinical use. PMID:27065795

  6. Rehabilitative interventions and brain plasticity in autism spectrum disorders: focus on MRI-based studies

    Directory of Open Access Journals (Sweden)

    Sara eCalderoni

    2016-03-01

    Full Text Available Clinical and research evidence supports the efficacy of rehabilitative intervention for improving targeted skills or global outcomes in individuals with autism spectrum disorder (ASD. However, putative mechanisms of structural and functional brain changes are poorly understood. This review aims to investigate the research literature on the neural circuit modifications after non-pharmacological intervention. For this purpose, longitudinal studies that used magnetic resonance imaging (MRI-based techniques at the start and at the end of the trial to evaluate the neural effects of rehabilitative treatment in subjects with ASD were identified. The six included studies involved a limited number of patients in the active group (from 2 to 16, and differed by acquisition method (task-related and resting-state functional MRI as well as by functional MRI tasks. Overall, the results produced by the selected investigations demonstrated brain plasticity during the treatment interval that results in an activation/functional connectivity more similar to those of subjects with typical development. Repeated MRI evaluation may represent a promising tool for the detection of neural changes in response to treatment in patients with ASD. However, large-scale randomized controlled trials after standardized rehabilitative intervention are required before translating these preliminary results into clinical use.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Progesterone mediates brain functional connectivity changes during the menstrual cycle - A pilot resting state MRI study

    Directory of Open Access Journals (Sweden)

    Katrin eArelin

    2015-02-01

    Full Text Available The growing interest in intrinsic brain organization has sparked various innovative approaches to generating comprehensive connectivity-based maps of the human brain. Prior reports point to a sexual dimorphism of the structural and functional human connectome. However, it is uncertain whether subtle changes in sex hormones, as occur during the monthly menstrual cycle, substantially impact the functional architecture of the female brain. Here, we performed eigenvector centrality (EC mapping in 32 longitudinal resting state fMRI scans of a single healthy subject without oral contraceptive use, across four menstrual cycles, and assessed estrogen and progesterone levels. To investigate associations between cycle-dependent hormones and brain connectivity, we performed correlation analyses between the EC maps and the respective hormone levels. On the whole brain level, we found a significant positive correlation between progesterone and EC in the bilateral DLPFC and bilateral sensorimotor cortex. In a secondary region-of-interest analysis, we detected a progesterone-modulated increase in functional connectivity of both bilateral DLPFC and bilateral sensorimotor cortex with the hippocampus. Our results suggest that the menstrual cycle substantially impacts intrinsic functional connectivity, particularly in brain areas associated with contextual memory-regulation, such as the hippocampus. These findings are the first to link the subtle hormonal fluctuations that occur during the menstrual cycle, to significant changes in regional functional connectivity in the hippocampus in a longitudinal design, given the limitation of data acquisition in a single subject. Our study demonstrates the feasibility of such a longitudinal rs-fMRI design and illustrates a means of creating a personalized map of the human brain by integrating potential mediators of brain states, such as menstrual cycle phase.

  9. A functional MRI study of the influence of sleep deprivation on digital memory in human brain

    Directory of Open Access Journals (Sweden)

    FAN Shuang-yi

    2013-05-01

    Full Text Available Background Working for long hours often leads to mental fatigue. There is evidence that mental fatigue is serious damage to cognitive function and behavior of the operator. Revealing the mechanism of continuous operation and sleep deprivation (SD on cognitive function, will help to combat the fatigue caused by continuous operation and to improve capacity of operators. This functional magnetic resonance imaging (fMRI study focused on the influence of sleep deprivation on digital memory in human brain. Methods Totally 6 healthy subjects underwent a digital memory encoding, maintenance and retrieval session during fMRI scanning before and after 48 h sleep deprivation. Results The digital memory test had the same error rate before and after sleep deprivation (P > 0.05, for all, but the reponse time of seven-number memory was longer after sleep deprivation (P = 0.005. During encoding trials decreased fMRI regions of significant activation between sleep control and sleep deprivation were in left parahippocampal gyrus Brodmann 30, left superior temporal gyrus Brodmann 42, left insular lobe Brodmann 41 and left frontal lobe Brodmann 6. During maintenance trials decreased fMRI regions of significant activation were at left superior temporal gyrus Brodmann 38, left middle temporal gyrus Brodmann 21, left parahippocampus and amygdaloid nucleus Brodmann 30, left middle frontal gyrus Brodmann 47, left lenticular nucleus and thalamus, right lenticular nucleus, left retrosplenial granular cortex Brodmann 30, right retrosplenial granular cortex Brodmann 30, bilateral cingulate gyrus Brodmann 24 and bilateral middle frontal gyrus, medial frontal gyrus Brodmann 6. During retrieval trials decreased fMRI regions of significantly positive activation were at bilateral hippocampus, right amygdaloid nucleus and inferior parietal lobule Brodmann 40, left precuneus Brodmann 19 and thalamus. Conclusion Different brain regions are activated at different stages of the

  10. Brain MRI Findings in Congenital Muscular Dystrophy

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    J Gordon Millichap

    2006-03-01

    Full Text Available Brain magnetic resonance imaging (MRI findings in 13 patients with congenital muscular dystrophy (MDCIC and Fukutin-related protein (FKRP gene mutations were retrospectively reviewed in a study at Hammersmith Hospital, London, UK, and European centers.

  11. 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

  12. 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.

  13. 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.)

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

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    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.

  15. A survey of MRI-based medical image analysis for brain tumor studies

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    Bauer, Stefan; Wiest, Roland; Nolte, Lutz-P.; Reyes, Mauricio

    2013-07-01

    MRI-based medical image analysis for brain tumor studies is gaining attention in recent times due to an increased need for efficient and objective evaluation of large amounts of data. While the pioneering approaches applying automated methods for the analysis of brain tumor images date back almost two decades, the current methods are becoming more mature and coming closer to routine clinical application. This review aims to provide a comprehensive overview by giving a brief introduction to brain tumors and imaging of brain tumors first. Then, we review the state of the art in segmentation, registration and modeling related to tumor-bearing brain images with a focus on gliomas. The objective in the segmentation is outlining the tumor including its sub-compartments and surrounding tissues, while the main challenge in registration and modeling is the handling of morphological changes caused by the tumor. The qualities of different approaches are discussed with a focus on methods that can be applied on standard clinical imaging protocols. Finally, a critical assessment of the current state is performed and future developments and trends are addressed, giving special attention to recent developments in radiological tumor assessment guidelines.

  16. Structural and Functional MRI Differences in Master Sommeliers: A Pilot Study on Expertise in the Brain.

    Science.gov (United States)

    Banks, Sarah J; Sreenivasan, Karthik R; Weintraub, David M; Baldock, Deanna; Noback, Michael; Pierce, Meghan E; Frasnelli, Johannes; James, Jay; Beall, Erik; Zhuang, Xiaowei; Cordes, Dietmar; Leger, Gabriel C

    2016-01-01

    Our experiences, even as adults, shape our brains. Regional differences have been found in experts, with the regions associated with their particular skill-set. Functional differences have also been noted in brain activation patterns in some experts. This study uses multimodal techniques to assess structural and functional patterns that differ between experts and non-experts. Sommeliers are experts in wine and thus in olfaction. We assessed differences in Master Sommeliers' brains, compared with controls, in structure and also in functional response to olfactory and visual judgment tasks. MRI data were analyzed using voxel-based morphometry as well as automated parcellation to assess structural properties, and group differences between tasks were calculated. Results indicate enhanced volume in the right insula and entorhinal cortex, with the cortical thickness of the entorhinal correlating with experience. There were regional activation differences in a large area involving the right olfactory and memory regions, with heightened activation specifically for sommeliers during an olfactory task. Our results indicate that sommeliers' brains show specialization in the expected regions of the olfactory and memory networks, and also in regions important in integration of internal sensory stimuli and external cues. Overall, these differences suggest that specialized expertise and training might result in enhancements in the brain well into adulthood. This is particularly important given the regions involved, which are the first to be impacted by many neurodegenerative diseases. PMID:27597821

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

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    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.

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

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    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.

  19. A Bold View Of The Lactating Brain: fMRI Studies Of Suckling in Awake Dams

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    Febo, Marcelo

    2011-01-01

    Functional MRI has been used to investigate the responsiveness of the maternal rat brain to pup-suckling under various experimental paradigms. Our research employing the lactating rat model has explored the cortical sensory processing of pup stimuli and the effect of suckling on the brain’s reward system. Suckling was observed to increase blood-oxygen-level-dependent (BOLD) signal intensity in the midbrain, striatum and prefrontal cortex, which are areas that receive prominent dopaminergic inputs. The BOLD activation of the reward system occurs in parallel with the activation of extensive cortical sensory areas. The observed regions include the olfactory cortex, auditory cortex and gustatory cortex and could correspond to cortical representations of pup odors, vocalizations and taste that are active during lactation. Activation patterns within reward regions are consistent with past research on maternal motivation and we explore the possibility that exposure to drugs of abuse might be disruptive of maternal neural responses to pups, particularly in the prefrontal cortex. Our ongoing fMRI studies support and extend past research on the maternal rat brain and its functional neurocircuitry. PMID:21722215

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

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    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

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

    International Nuclear Information System (INIS)

    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 18F-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

  2. 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.

  3. 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 (Tesla fMRI scanner's baseline noise variation (∼.85±.1%). Finally, HFI is 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. PMID:24110643

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

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    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.

  5. 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.

  6. In-vivo longitudinal MRI study: an assessment of melanoma brain metastases in a clinically relevant mouse model.

    Science.gov (United States)

    Henry, Mariama N; Chen, Yuhua; McFadden, Catherine D; Simedrea, Felicia C; Foster, Paula J

    2015-04-01

    Brain metastases are an important clinical problem. Few animal models exist for melanoma brain metastases; many of which are not clinically relevant. Longitudinal MRI was implemented to examine the development of tumors in a clinically relevant mouse model of melanoma brain metastases. Fifty thousand human metastatic melanoma (A2058) cells were injected intracardially into nude mice. Three Tesla MRI was performed using a custom-built gradient insert coil and a mouse solenoid head coil. Imaging was performed on consecutive days at four time points. Tumor burden and volumes of metastases were measured from balanced steady-state free precession image data. Metastases with a disrupted blood-tumor barrier were identified from T1-weighted spin echo images acquired after administration of gadopentetic acid (Gd-DTPA). Metastases permeable to Gd-DTPA showed signal enhancement. The number of enhancing metastases was determined by comparing balanced steady-state free precession images with T1-weighted spin echo images. After the final imaging session, ex-vivo permeability and histological analyses were carried out. Imaging showed that both enhancing and nonenhancing brain metastases coexist in the brain, and that most metastases switched from the nonenhancing to the enhancing phenotype. Small numbers of brain metastases were enhancing when first detected by MRI and remained enhancing, whereas other metastases remained nonenhancing to Gd-DTPA throughout the experiment. No clear relationship existed between the permeability of brain metastases and size, brain location and age. Longitudinal in-vivo MRI is key to studying the complex and dynamic processes of metastasis and changes in the blood-tumor barrier permeability, which may lead to a better understanding of the variable responses of brain metastases to treatments. PMID:25513779

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

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    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.

  8. Pathological and MRI study on experimental heroin-induced brain damage in rats

    International Nuclear Information System (INIS)

    Objective: To study the pathological characteristics of the heroin-induced brain damage in rats, and to assess the diagnostic value of MRI. Methods: A total of 40 adult Wistar rats were studied, 32 rats were used for injecting heroin as heroin group and 8 were used for injecting saline as control group. The heroin dependent rat model was established by administering heroin (ip) in the ascending dosage schedule (0.5 mg/kg), three times a day (at 8:00, 12:00, and 18:00). The control group was established by the same way by injection with saline. The withdrawal scores were evaluated with imp roved criterion in order to estimate the degree of addiction after administering naloxone. Based on the rat model of heroin dependence, the rat model of heroin-induced brain damage was established by the same way with increasing heroin dosage everyday. Two groups were examined by using MRI, light microscope, and electron microscope, respectively in different heroin accumulated dosage (918, 1580, 2686, 3064, 4336, and 4336 mg/kg withdrawal after 2 weeks). Results: There was statistically significant difference (t=9.737, P<0.01) of the withdrawal scores between the heroin dependent group and the saline group (23.0 ± 4.4 and 1.4 ± 0.5, respectively). It suggested that the heroin dependent rat model be established successfully. In different accumulated dosage ( from 1580 mg/kg to 4336 mg/kg), there were degeneration and death of nerve cells in cerebrum and cerebellum of heroin intoxicated rats, and it suggested that the rat model of heroin-induced brain damage was established successfully. The light microscope and electron microscope features of heroin-induced brain damage in rats included: (1) The nerve cells of cerebral cortex degenerated and died. According to the heroin accumulated dosage, there were statistically significant difference of the nerve cell deaths between 4336 mg/kg group and 1580 mg/kg group or control group (P=0.024 and P=0.032, respectively); (2) The main

  9. MRI-controlled interstitial ultrasound brain therapy: An initial in-vivo study

    Science.gov (United States)

    N'Djin, W. Apoutou; Burtnyk, Mathieu; Lipsman, Nir; Bronskill, Michael; Schwartz, Michael; Kucharczyk, Walter; Chopra, Rajiv

    2012-11-01

    The recent emergence at the clinical level of minimally-invasive focal therapy such as laser-induced thermal therapy (LITT) has demonstrated promise in the management of brain metastasis [1], although control over the spatial pattern of heating is limited. Delivery of HIFU from minimally-invasive applicators enables high spatial control of the heat deposition in biological tissues, large treatment volumes and high treatment rate in well chosen conditions [2,3]. In this study, the feasibility of MRI-guided interstitial ultrasound therapy in brain was studies in-vivo in a porcine model. A prototype system originally developed for transurethral ultrasound therapy [4,5,6] was used in this study. Two burr holes of 12 mm in diameter were created in the animal's skull to allow the insertion of the therapeutic ultrasound applicator (probe) into the brain at two locations (right and left frontal lobe). A 4-element linear ultrasound transducer (f = 8 MHz) was mounted at the tip of a 25-cm linear probe (6 mm in diameter). The target boundary was traced to cover in 2D a surface compatible with the treatment of a 2 cm brain tumor. Acoustic power of each element and rotation rate of the device were adjusted in real-time based on MR-thermometry feedback control to optimize heat deposition at the target boundary [2,4,5]. Two MRT-controlled ultrasound brain treatments per animal have been performed using a maximal surface acoustic power of 10W.cm-2. In all cases, it was possible to increase accurately the temperature of the brain tissues in the targeted region over the 55°C threshold necessary for the creation of irreversible thermal lesion. Tissue changes were visible on T1w contrast-enhanced images immediately after treatment. These changes were also evident on T2w FSE images taken 2 hours after the 1st treatment and correlated well with the temperature image. On average, the targeted volume was 4.7 ± 2.3 cm3 and the 55°C treated volume was 6.7 ± 4.4 cm3. The volumetric

  10. Consistency of parametric registration in serial MRI studies of brain tumor progression

    International Nuclear Information System (INIS)

    The consistency of parametric registration in multi-temporal magnetic resonance (MR) imaging studies was evaluated. Serial MRI scans of adult patients with a brain tumor (glioma) were aligned by parametric registration. The performance of low-order spatial alignment (6/9/12 degrees of freedom) of different 3D serial MR-weighted images is evaluated. A registration protocol for the alignment of all images to one reference coordinate system at baseline is presented. Registration results were evaluated for both, multimodal intra-timepoint and mono-modal multi-temporal registration. The latter case might present a challenge to automatic intensity-based registration algorithms due to ill-defined correspondences. The performance of our algorithm was assessed by testing the inverse registration consistency. Four different similarity measures were evaluated to assess consistency. Careful visual inspection suggests that images are well aligned, but their consistency may be imperfect. Sub-voxel inconsistency within the brain was found for allsimilarity measures used for parametric multi-temporal registration. T1-weighted images were most reliable for establishing spatial correspondence between different timepoints. The parametric registration algorithm is feasible for use in this application. The sub-voxel resolution mean displacement error of registration transformations demonstrates that the algorithm converges to an almost identical solution for forward and reverse registration. (orig.)

  11. 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.

  12. 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

  13. Brain Correlates of Self-Evaluation Deficits in Schizophrenia: A Combined Functional and Structural MRI Study.

    Directory of Open Access Journals (Sweden)

    Shuping Tan

    Full Text Available Self-evaluation plays an important role in adaptive functioning and is a process that is typically impaired in patients with schizophrenia. Underlying neural mechanisms for this dysfunction may be associated with manifested psychosis. However, the brain substrates underlying this deficit are not well known. The present study used brain blood oxygen level dependent (BOLD functional magnetic resonance imaging (fMRI and gray matter voxel-based morphometry to explore the functional and structural brain correlates of self-evaluation deficits in schizophrenia. Eighteen patients with schizophrenia and 17 healthy controls were recruited and asked to judge whether a set of personality-trait adjectives were appropriate for describing themselves, a familiar other, or whether the adjectives were of positive or negative valence. Patients had slower response times for negative trait attributions than controls did; responses to positive trait attributions were faster than those for negative traits among the patient group, while no differences were observed in the control group. Control subjects showed greater activation within the dorsal medial prefrontal cortex (dMPFC and the anterior cingulate cortex (ACC than the patient group during the self-evaluation > semantic positivity-evaluation contrast. Patients showed greater activation mainly within the posterior cingulate gyrus (PCC as compared to controls for the other-evaluation > semantic positivity-evaluation contrast. Furthermore, gray matter volume was reduced in the MPFC, temporal lobe, cuneus, and the dorsal lateral prefrontal cortex (DLPFC among the patient group when compared to controls. The present study adds to previous findings regarding self- and other-referential processing in schizophrenia, providing support for neurobiological models of self-reflection impairment.

  14. Brain MRI abnormalities in neuromyelitis optica

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. The importance of combining MRI and large-scale digital histology in neuroimaging studies of brain connectivity and disease.

    Directory of Open Access Journals (Sweden)

    Jacopo eAnnese

    2012-04-01

    Full Text Available One of the major issues hindering a comprehensive connectivity model for the human brain is the difficulty in linking Magnetic Resonance Imaging (MRI to anatomical evidence produced by histological methods. Non-invasive and postmortem neuroimaging methodologies are still largely incompatible in terms of sample size, scale, and resolution. To help bridge the hiatus between different approaches we established a program that characterizes the brain of individual subjects, combining in vivo MRI with postmortem neuroanatomy. The direct correlation of MRI and histological features is possible, because registered images from different modalities represent the same regions in the same brain. Our comparisons are also facilitated by large-scale, digital microscopy techniques that afford images of the whole-brain sections at cellular resolution. The goal is to create a neuroimaging catalogue representative of discrete age groups and specific neurological conditions. Individually, the datasets allow for investigating the relationship between different modalities; combined, they provide sufficient predictive power to inform analyses and interpretations made in the context of exclusively non-invasive studies of brain connectivity and disease.

  16. 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.

  17. 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. PMID:26119472

  18. Creating probabilistic maps of the face network in the adolescent brain: A multi-centre functional MRI study

    International Nuclear Information System (INIS)

    Large-scale magnetic resonance (MR) studies of the human brain offer unique opportunities for identifying genetic and environmental factors shaping the human brain. Here, we describe a dataset collected in the context of a multi-centre study of the adolescent brain, namely the IMAGEN Study. We focus on one of the functional paradigms included in the project to probe the brain network underlying processing of ambiguous and angry faces. Using functional MR (fMRI) data collected in 1,110 adolescents, we constructed probabilistic maps of the neural network engaged consistently while viewing the ambiguous or angry faces; 21 brain regions responding to faces with high probability were identified. We were also able to address several methodological issues, including the minimal sample size yielding a stable location of a test region, namely the fusiform face area (FFA), as well as the effect of acquisition site (eight sites) and scanner (four manufacturers) on the location and magnitude of the fMRI response to faces in the FFA. Finally, we provided a comparison between male and female adolescents in terms of the effect sizes of sex differences in brain response to the ambiguous and angry faces in the 21 regions of interest. Overall, we found a stronger neural response to the ambiguous faces in several cortical regions, including the fusiform face area, in female (vs. male) adolescents, and a slightly stronger response to the angry faces in the amygdala of male (vs. female) adolescents. (authors)

  19. Brain activation profiles during kinesthetic and visual imagery: An fMRI study.

    Science.gov (United States)

    Kilintari, Marina; Narayana, Shalini; Babajani-Feremi, Abbas; Rezaie, Roozbeh; Papanicolaou, Andrew C

    2016-09-01

    The aim of this study was to identify brain regions involved in motor imagery and differentiate two alternative strategies in its implementation: imagining a motor act using kinesthetic or visual imagery. Fourteen adults were precisely instructed and trained on how to imagine themselves or others perform a movement sequence, with the aim of promoting kinesthetic and visual imagery, respectively, in the context of an fMRI experiment using block design. We found that neither modality of motor imagery elicits activation of the primary motor cortex and that each of the two modalities involves activation of the premotor area which is also activated during action execution and action observation conditions, as well as of the supplementary motor area. Interestingly, the visual and the posterior cingulate cortices show reduced BOLD signal during both imagery conditions. Our results indicate that the networks of regions activated in kinesthetic and visual imagery of motor sequences show a substantial, while not complete overlap, and that the two forms of motor imagery lead to a differential suppression of visual areas. PMID:27288703

  20. Neonatal brain injury and neuroanatomy of memory processing following very preterm birth in adulthood: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Anastasia K Kalpakidou

    Full Text Available Altered functional neuroanatomy of high-order cognitive processing has been described in very preterm individuals (born before 33 weeks of gestation; VPT compared to controls in childhood and adolescence. However, VPT birth may be accompanied by different types of adverse neonatal events and associated brain injury, the severity of which may have differential effects on brain development and subsequent neurodevelopmental outcome. We conducted a functional magnetic resonance imaging (fMRI study to investigate how differing degrees of neonatal brain injury, detected by neonatal ultrasounds, affect the functional neuroanatomy of memory processing in VPT young adults. We used a verbal paired associates learning task, consisting of four encoding, four cued-recall and four baseline condition blocks. To further investigate whether differences in neural activation between the groups were modulated by structural brain changes, structural MRI data were also collected. We studied 12 VPT young adults with a history of periventricular haemorrhage with associated ventricular dilatation, 17 VPT individuals with a history of uncomplicated periventricular haemorrhage, 12 individuals with normal ultrasonographic findings, and 17 controls. Results of a linear trend analysis demonstrated that during completion of the paired associates learning task right frontal and right parietal brain activation decreased as the severity of neonatal brain injury increased. There were no statistically significant between-group differences in on-line task performance and participants' intelligence quotient (IQ at assessment. This pattern of differential activation across the groups was observed particularly in the right middle frontal gyrus during encoding and in the right posterior cingulate gyrus during recall. Structural MRI data analysis revealed that grey matter volume in the right superior temporal gyrus, right cerebellum, left middle temporal gyrus, right globus pallidus and

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Association of white-matter lesions with brain atrophy markers: the three-city Dijon MRI study

    International Nuclear Information System (INIS)

    Background: Brain atrophy and white-matter lesions (WML) are common features at cerebral MRI of both normal and demented elderly people. In a population-based study of 1, 792 elderly subjects aged 65-80 years, free of dementia, who had a cerebral MRI at entry, we investigated the relationship between WML volume and brain atrophy markers estimated by hippocampal, gray matter (GM) and cerebrospinal fluid (CSF) volumes. Methods: An automated algorithm of detection and quantification of WML was developed, and voxel-based morphometry methods were used to estimate GM, CSF and hippocampal volumes. To evaluate the relation between those volumes and WML load, we used analysis of covariance and multiple linear regression models adjusting for potential confounders and total intracranial volumes. Results: Age was highly correlated with WML load and all brain atrophy markers. Total WML volume was negatively associated with both GM (β = -0.03, p ≤ 0.0001) and hippocampal volumes (β = -0.75, p = 0.0009) and positively with CSF volumes (beta 0.008, p = 0.02) after controlling for sex, age, education level, hypertension and apolipoprotein E genotype. Evidence for a relationship between brain atrophy markers and WML was stronger for periventricular WML. We found that the relationship between WML and hippocampal volumes was independent of other brain tissue volumes. Conclusion: These results suggest that, in the brain of non demented elderly subjects, degenerative processes and vascular changes co-occur and are related independently of vascular risk factors. (authors)

  3. 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

  4. 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.

  5. 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.

  6. Pictorial essay: MRI of the fetal brain

    OpenAIRE

    B, Ganesh Rao; Ramamurthy, BS

    2009-01-01

    MRI is a useful supplement to USG for the assessment of fetal brain malformations. Superior soft tissue contrast and the ability to depict sulcation and myelination are the strengths of MRI. Subtle or inconclusive USG abnormalities can be confirmed or ruled out by MRI. In some cases, additional findings detected with MRI often help in arriving at a definitive diagnosis, which is necessary for parental counseling and for guiding management. Fast T2W sequences form the basis of fetal MRI. There...

  7. Thirty minute transcutaneous electric acupoint stimulation modulates resting state brain activities: a perfusion and BOLD fMRI study.

    Science.gov (United States)

    Jiang, Yin; Hao, Ying; Zhang, Yue; Liu, Jing; Wang, Xiaoying; Han, Jisheng; Fang, Jing; Zhang, Jue; Cui, Cailian

    2012-05-31

    Increasing neuroimaging studies have focused on the sustained after effects of acupuncture, especially for the changes of brain activities in rest. However, short-period stimuli have mostly been chosen in these works. The present study aimed to investigate how the resting state brain activities in healthy subjects were modulated by relatively long-period (30 min) acupuncture, a widely used modality in clinical practice. Transcutaneous electric acupoint stimulation (TEAS) or intermittent minimal TEAS (MTEAS) were given for 30 min to 40 subjects. Functional MRI (fMRI) data were collected including the pre-stimulation resting state and the post-stimulation resting state, using dual-echo arterial spin labeling (ASL) techniques, representing both cerebral blood flow (CBF) signals and blood oxygen-dependent level (BOLD) signals simultaneously. Following 30 min TEAS, but not MTEAS, the mean global CBF decreased, and a significant decrease of regional CBF was observed in SI, insula, STG, MOG and IFG. Functional connectivity analysis showed more secure and spatially extended connectivity of both the DMN and SMN after 30 min TEAS. Our results implied that modulation of the regional brain activities and network connectivity induced by thirty minute TEAS may associate with the acupuncture-related therapeutic effects. Furthermore, the resting state regional CBF quantified by ASL perfusion fMRI may serve as a potential biomarker in future acupuncture studies. PMID:22541167

  8. Pictorial essay: MRI of the fetal brain

    International Nuclear Information System (INIS)

    MRI is a useful supplement to USG for the assessment of fetal brain malformations. Superior soft tissue contrast and the ability to depict sulcation and myelination are the strengths of MRI. Subtle or inconclusive USG abnormalities can be confirmed or ruled out by MRI. In some cases, additional findings detected with MRI often help in arriving at a definitive diagnosis, which is necessary for parental counseling and for guiding management. Fast T2W sequences form the basis of fetal MRI. There have been no reports of deleterious effects of MRI on the fetus. A few case examples are presented to illustrate the advantages of MRI

  9. Deep brain stimulation for Parkinson's disease dissociates mood and motor circuits: a functional MRI case study.

    Science.gov (United States)

    Stefurak, Taresa; Mikulis, David; Mayberg, Helen; Lang, Anthony E; Hevenor, Stephanie; Pahapill, Peter; Saint-Cyr, Jean; Lozano, Andres

    2003-12-01

    Behavioral disturbances have been reported with subthalamic (STN) deep brain stimulation (DBS) treatment in Parkinson's disease (PD). We report correlative functional imaging (fMRI) of mood and motor responses induced by successive right and left DBS. A 36-year-old woman with medically refractory PD and a history of clinically remitted depression underwent uncomplicated implantation of bilateral STN DBS. High-frequency stimulation of the left electrode improved motor symptoms. Unexpectedly, right DBS alone elicited several reproducible episodes of acute depressive dysphoria. Structural and functional magnetic resonance imaging (fMRI) imaging was carried out with sequential individual electrode stimulation. The electrode on the left was within the inferior STN, whereas the right electrode was marginally superior and lateral to the intended STN target within the Fields of Forel/zona incerta. fMRI image analysis (Analysis of Functional NeuroImages, AFNI) contrasting OFF versus ON stimulation identified significant lateralized blood oxygen level-dependent (BOLD) signal changes with DBS (P disturbance resolved spontaneously in 4 weeks despite identical stimulation parameters. Transient depressive mood induced by subcortical DBS stimulation was correlated with changes in mesolimbic cortical structures. This case provides new evidence supporting cortical segregation of motor and nonmotor cortico-basal ganglionic systems that may converge in close proximity at the level of the STN and the adjacent white matter tracts (Fields of Forel/zona incerta). PMID:14673888

  10. 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

  11. 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.

  12. 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.

  13. Brain connectivity network models based on multi-modal MRI to study brain reorganization of prenatal origin using intrauterine growth restriction as a model

    OpenAIRE

    Batallé Bolaño, Dafnis

    2014-01-01

    This PhD thesis is focused in the application of brain network models obtained from different modalities of magnetic resonance imaging (MRI) to characterize anomalies in neurodevelopment of a prenatal origin, using intrauterine growth restriction (IUGR) as a clinical model. Importantly, IUGR due to placental insufficiency affects 5-10% of all pregnancies and is a leading cause of fetal morbidity and mortality. The thesis is presented as a compendium of four studies published in internatio...

  14. 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.

  15. 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.)

  16. The Effect of Aging on Resting-State Brain Function: An fMRI Study

    Directory of Open Access Journals (Sweden)

    A. H. Batouli

    2009-11-01

    Full Text Available Background/Objective: Healthy aging may be accompanied by some types of cognitive impairment; moreover, normal aging may cause natural atrophy in the healthy human brain. The hypothesis of the healthy aging brain is the structural changes together with the functional impairment happening. The brain struggles to over-compensate for those functional age-related impairments to continue as a healthy brain in its functions. Our goal in this study was to evaluate the effects of aging on the resting-state activation network of the brain using the multi-session probabilistic independent component analysis algorithm (PICA. "nPatients and Methods: We compared the resting-state brain activities between two groups of healthy aged and young subjects, so we examined 30 right-handed subjects and finally 12 healthy aging and 11 controls were enrolled in the study. "nResults: Our results showed that during the resting-state, older brains benefit from larger areas of activation, while in young competent brains, higher activation occurs in terms of greater intensity. These results were obtained in prefrontal areas as regions with regard to memory function as well as the posterior cingulate cortex (PCC as parts of the default mode network. Meanwhile, we reached the same results after normalization of activation size with total brain volume. "nConclusion: The difference in activation patterns between the two groups shows the brain's endeavor to compensate the functional impairment.

  17. Brain activation in response to randomized visual stimulation as obtained from conjunction and differential analysis: an fMRI study

    International Nuclear Information System (INIS)

    The objective of this multiple-subjects functional magnetic resonance imaging (fMRI) study was to identify the common brain areas that are activated when viewing black-and-white checkerboard pattern stimuli of various shapes, pattern and size and to investigate specific brain areas that are involved in processing static and moving visual stimuli. Sixteen participants viewed the moving (expanding ring, rotating wedge, flipping hour glass and bowtie and arc quadrant) and static (full checkerboard) stimuli during an fMRI scan. All stimuli have black-and-white checkerboard pattern. Statistical parametric mapping (SPM) was used in generating brain activation. Differential analyses were implemented to separately search for areas involved in processing static and moving stimuli. In general, the stimuli of various shapes, pattern and size activated multiple brain areas mostly in the left hemisphere. The activation in the right middle temporal gyrus (MTG) was found to be significantly higher in processing moving visual stimuli as compared to static stimulus. In contrast, the activation in the left calcarine sulcus and left lingual gyrus were significantly higher for static stimulus as compared to moving stimuli. Visual stimulation of various shapes, pattern and size used in this study indicated left lateralization of activation. The involvement of the right MTG in processing moving visual information was evident from differential analysis, while the left calcarine sulcus and left lingual gyrus are the areas that are involved in the processing of static visual stimulus

  18. Motion correction in MRI of the brain

    Science.gov (United States)

    Godenschweger, F.; Kägebein, U.; Stucht, D.; Yarach, U.; Sciarra, A.; Yakupov, R.; Lüsebrink, F.; Schulze, P.; Speck, O.

    2016-03-01

    Subject motion in MRI is a relevant problem in the daily clinical routine as well as in scientific studies. Since the beginning of clinical use of MRI, many research groups have developed methods to suppress or correct motion artefacts. This review focuses on rigid body motion correction of head and brain MRI and its application in diagnosis and research. It explains the sources and types of motion and related artefacts, classifies and describes existing techniques for motion detection, compensation and correction and lists established and experimental approaches. Retrospective motion correction modifies the MR image data during the reconstruction, while prospective motion correction performs an adaptive update of the data acquisition. Differences, benefits and drawbacks of different motion correction methods are discussed.

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

    OpenAIRE

    Tom A Schweizer; Karen Kan; Yuwen Hung; Fred Tam; Gary Naglie; Simon Graham

    2013-01-01

    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. Materials and Methods: To capture brain activity during driving, we placed a driving simulator with a fully functio...

  20. 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.

  1. 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. PMID:26161117

  2. 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.

  3. 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.

  4. Alcohol Dose Effects on Brain Circuits During Simulated Driving: An fMRI Study

    OpenAIRE

    Meda, Shashwath A; Calhoun, Vince D.; Astur, Robert S.; Turner, Beth M.; Ruopp, Kathryn; Pearlson, Godfrey D.

    2009-01-01

    Driving while intoxicated remains a major public health hazard. Driving is a complex task involving simultaneous recruitment of multiple cognitive functions. The investigators studied the neural substrates of driving and their response to different blood alcohol concentrations (BACs), using functional magnetic resonance imaging (fMRI) and a virtual reality driving simulator. We used independent component analysis (ICA) to isolate spatially independent and temporally correlated driving-related...

  5. Progressive brain changes in children and adolescents with early-onset psychosis:A meta-analysis of longitudinal MRI studies

    OpenAIRE

    Fraguas, David; Díaz-Caneja, Covadonga M.; Pina-Camacho, Laura; Janssen, Joost; Arango, Celso

    2016-01-01

    Background: Studies on longitudinal brain volume changes in patients with early-onset psychosis (EOP) are particularly valuable for understanding the neurobiological basis of brain abnormalities associated with psychosis. However, findings have not been consistent across studies in this population. We aimed to conduct a meta-analysis on progressive brain volume changes in children and adolescents with EOP. Methods: A systematic literature search of magnetic resonance imaging (MRI) studies com...

  6. D-BRAIN: Anatomically Accurate Simulated Diffusion MRI Brain Data.

    Science.gov (United States)

    Perrone, Daniele; Jeurissen, Ben; Aelterman, Jan; Roine, Timo; Sijbers, Jan; Pizurica, Aleksandra; Leemans, Alexander; Philips, Wilfried

    2016-01-01

    Diffusion Weighted (DW) MRI allows for the non-invasive study of water diffusion inside living tissues. As such, it is useful for the investigation of human brain white matter (WM) connectivity in vivo through fiber tractography (FT) algorithms. Many DW-MRI tailored restoration techniques and FT algorithms have been developed. However, it is not clear how accurately these methods reproduce the WM bundle characteristics in real-world conditions, such as in the presence of noise, partial volume effect, and a limited spatial and angular resolution. The difficulty lies in the lack of a realistic brain phantom on the one hand, and a sufficiently accurate way of modeling the acquisition-related degradation on the other. This paper proposes a software phantom that approximates a human brain to a high degree of realism and that can incorporate complex brain-like structural features. We refer to it as a Diffusion BRAIN (D-BRAIN) phantom. Also, we propose an accurate model of a (DW) MRI acquisition protocol to allow for validation of methods in realistic conditions with data imperfections. The phantom model simulates anatomical and diffusion properties for multiple brain tissue components, and can serve as a ground-truth to evaluate FT algorithms, among others. The simulation of the acquisition process allows one to include noise, partial volume effects, and limited spatial and angular resolution in the images. In this way, the effect of image artifacts on, for instance, fiber tractography can be investigated with great detail. The proposed framework enables reliable and quantitative evaluation of DW-MR image processing and FT algorithms at the level of large-scale WM structures. The effect of noise levels and other data characteristics on cortico-cortical connectivity and tractography-based grey matter parcellation can be investigated as well. PMID:26930054

  7. Brain structure and the relationship with neurocognitive functioning in schizophrenia and bipolar disorder : MRI studies

    OpenAIRE

    2011-01-01

    Brain structural abnormalities as well as neurocognitive dysfunction, are found in schizophrenia and in bipolar disorder. Based on the fact that both brain structure and neurocognitive functioning are significantly heritable and affected in both schizophrenia and bipolar disorder, relationships between them are expected. However, previous studies report inconsistent findings. Also, schizophrenia and bipolar disorder are classified as separate disease entities, but demonstrate overlap with reg...

  8. 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

  9. Brain MRI findings of carbon disulfide poisoning

    International Nuclear Information System (INIS)

    To evaluate the findings of brain MRI in patients with carbon disulfide poisoning. Ninety-one patients who had suffered carbon disulfide poisoning [male:female=87:4; age, 32-74 (mean 53.3) years] were included in this study. To determine the extent of white matter hyperintensity (Grade 0-V) and lacunar infarction, T2-weighted MR imaging of the brain was performed. T2-weighted images depicted white matter hyperintensity in 70 patients (76.9%) and lacunar infarcts in 27 (29.7%). In these patients, the prevalent findings at T2-weighted MR imaging of the brain were white matter hyperintensity and lacunar infarcts. Disturbance of the cardiovascular system by carbon disulfide might account for these results

  10. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    International Nuclear Information System (INIS)

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain

  11. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    Science.gov (United States)

    Ismail, S. S.; Mohamad, M.; Syazarina, S. O.; Nafisah, W. Y.

    2014-11-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain.

  12. 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.)

  13. 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

    International Nuclear Information System (INIS)

    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.)

  14. Physiological neuronal decline in healthy aging human brain - An in vivo study with MRI and short echo-time whole-brain (1)H MR spectroscopic imaging.

    Science.gov (United States)

    Ding, Xiao-Qi; Maudsley, Andrew A; Sabati, Mohammad; Sheriff, Sulaiman; Schmitz, Birte; Schütze, Martin; Bronzlik, Paul; Kahl, Kai G; Lanfermann, Heinrich

    2016-08-15

    Knowledge of physiological aging in healthy human brain is increasingly important for neuroscientific research and clinical diagnosis. To investigate neuronal decline in normal aging brain eighty-one healthy subjects aged between 20 and 70years were studied with MRI and whole-brain (1)H MR spectroscopic imaging. Concentrations of brain metabolites N-acetyl-aspartate (NAA), choline (Cho), total creatine (tCr), myo-inositol (mI), and glutamine+glutamate (Glx) in ratios to internal water, and the fractional volumes of brain tissue were estimated simultaneously in eight cerebral lobes and in cerebellum. Results demonstrated that an age-related decrease in gray matter volume was the largest contribution to changes in brain volume. Both lobar NAA and the fractional volume of gray matter (FVGM) decreased with age in all cerebral lobes, indicating that the decreased NAA was predominantly associated with decreased gray matter volume and neuronal density or metabolic activity. In cerebral white matter Cho, tCr, and mI increased with age in association with increased fractional volume, showing altered cellular membrane turn-over, energy metabolism, and glial activity in human aging white matter. In cerebellum tCr increased while brain tissue volume decreased with age, showing difference to cerebral aging. The observed age-related metabolic and microstructural variations suggest that physiological neuronal decline in aging human brain is associated with a reduction of gray matter volume and neuronal density, in combination with cellular aging in white matter indicated by microstructural alterations and altered energy metabolism in the cerebellum. PMID:27164326

  15. 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

  16. 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

  17. Brain Morphometry using MRI in Schizophrenia Patients

    Science.gov (United States)

    Abanshina, I.; Pirogov, Yu.; Kupriyanov, D.; Orlova, V.

    2010-01-01

    Schizophrenia has been the focus of intense neuroimaging research. Although its fundamental pathobiology remains elusive, neuroimaging studies provide evidence of abnormalities of cerebral structure and function in patients with schizophrenia. We used morphometry as a quantitative method for estimation of volume of brain structures. Seventy eight right-handed subjects aged 18-45 years were exposed to MRI-examination. Patients were divided into 3 groups: patients with schizophrenia, their relatives and healthy controls. The volumes of interested structures (caudate nucleus, putamen, ventricles, frontal and temporal lobe) were measured using T2-weighted MR-images. Correlations between structural differences and functional deficit were evaluated.

  18. Migraine with aura and risk of silent brain infarcts and white matter hyperintensities: an MRI study.

    Science.gov (United States)

    Gaist, David; Garde, Ellen; Blaabjerg, Morten; Nielsen, Helle H; Krøigård, Thomas; Østergaard, Kamilla; Møller, Harald S; Hjelmborg, Jacob; Madsen, Camilla G; Iversen, Pernille; Kyvik, Kirsten O; Siebner, Hartwig R; Ashina, Messoud

    2016-07-01

    A small number of population-based studies reported an association between migraine with aura and risk of silent brain infarcts and white matter hyperintensities in females. We investigated these relations in a population-based sample of female twins. We contacted female twins ages 30-60 years identified through the population-based Danish Twin Registry. Based on questionnaire responses, twins were invited to participate in a telephone-based interview conducted by physicians. Headache diagnoses were established according to the International Headache Society criteria. Cases with migraine with aura, their co-twins, and unrelated migraine-free twins (controls) were invited to a brain magnetic resonance imaging scan performed at a single centre. Brain scans were assessed for the presence of infarcts, and white matter hyperintensities (visual rating scales and volumetric analyses) blinded to headache diagnoses. Comparisons were based on 172 cases, 34 co-twins, and 139 control subjects. Compared with control subjects, cases did not differ with regard to frequency of silent brain infarcts (four cases versus one control), periventricular white matter hyperintensity scores [adjusted mean difference (95% confidence interval): -0.1 (-0.5 to 0.2)] or deep white matter hyperintensity scores [adjusted mean difference (95% confidence interval): 0.1 (-0.8 to 1.1)] assessed by Scheltens' scale. Cases had a slightly higher total white matter hyperintensity volume compared with controls [adjusted mean difference (95% confidence interval): 0.17 (-0.08 to 0.41) cm(3)] and a similar difference was present in analyses restricted to twin pairs discordant for migraine with aura [adjusted mean difference 0.21 (-0.20 to 0.63)], but these differences did not reach statistical significance. We found no evidence of an association between silent brain infarcts, white matter hyperintensities, and migraine with aura. PMID:27190013

  19. 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. PMID:22997054

  20. 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.

  1. [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.

  2. 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.

  3. 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.

  4. Cognition and brain abnormalities on MRI in pituitary patients

    International Nuclear Information System (INIS)

    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

  5. 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

  6. 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

  7. 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).

  8. 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.

  9. MRI Study on the Functional and Spatial Consistency of Resting State-Related Independent Components of the Brain Network

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Bum Seok [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Choi, Jee Wook [Daejeon St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Daejeon (Korea, Republic of); Kim, Ji Woong [College of Medical Science, Konyang University, Daejeon(Korea, Republic of)

    2012-06-15

    Resting-state networks (RSNs), including the default mode network (DMN), have been considered as markers of brain status such as consciousness, developmental change, and treatment effects. The consistency of functional connectivity among RSNs has not been fully explored, especially among resting-state-related independent components (RSICs). This resting-state fMRI study addressed the consistency of functional connectivity among RSICs as well as their spatial consistency between 'at day 1' and 'after 4 weeks' in 13 healthy volunteers. We found that most RSICs, especially the DMN, are reproducible across time, whereas some RSICs were variable in either their spatial characteristics or their functional connectivity. Relatively low spatial consistency was found in the basal ganglia, a parietal region of left frontoparietal network, and the supplementary motor area. The functional connectivity between two independent components, the bilateral angular/supramarginal gyri/intraparietal lobule and bilateral middle temporal/occipital gyri, was decreased across time regardless of the correlation analysis method employed, (Pearson's or partial correlation). RSICs showing variable consistency are different between spatial characteristics and functional connectivity. To understand the brain as a dynamic network, we recommend further investigation of both changes in the activation of specific regions and the modulation of functional connectivity in the brain network.

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

    International Nuclear Information System (INIS)

    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.

  11. 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.

  12. 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.

  13. 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

  14. 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.)

  15. Discriminative Analysis of Nonlinear Brain Connectivity in Schizophrenia: An fMRI Study

    Directory of Open Access Journals (Sweden)

    Longfei eSu

    2013-10-01

    Full Text Available Background: Dysfunctional integration of distributed brain networks is believed to be the cause of schizophrenia, and resting-state functional connectivity analyses of schizophrenia have attracted considerable attention in recent years. Unfortunately, existing functional connectivity analyses of schizophrenia have been mostly limited to linear associations.Objective: The objective of the present study is to evaluate the discriminative power of nonlinear functional connectivity and identify its changes in schizophrenia.Method: A novel measure utilizing the extended maximal information coefficient was introduced to construct nonlinear functional connectivity. In conjunction with multivariate pattern analysis, the new functional connectivity successfully discriminated schizophrenic patients from healthy controls with relative higher accuracy rate than the linear measure.Result: We found that the strength of the identified nonlinear functional connections involved in the classification increased in patients with schizophrenia, which was opposed to its linear counterpart. Further functional network analysis revealed that the changes of the nonlinear and linear connectivity have similar but not completely the same spatial distribution in human brain.Conclusion: The classification results suggest that the nonlinear functional connectivity provided useful discriminative power in diagnosis of schizophrenia, and the inverse but similar spatial distributed changes between the nonlinear and linear measure may indicate the underlying compensatory mechanism and the complex neuronal synchronization underlying the symptom of schizophrenia.

  16. MRI findings of miliary tuberculosis of the brain

    International Nuclear Information System (INIS)

    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

  17. 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.

  18. Brain networks involved in haptic and visual identification of facial expressions of emotion: an fMRI study.

    Science.gov (United States)

    Kitada, Ryo; Johnsrude, Ingrid S; Kochiyama, Takanori; Lederman, Susan J

    2010-01-15

    Previous neurophysiological and neuroimaging studies have shown that a cortical network involving the inferior frontal gyrus (IFG), inferior parietal lobe (IPL) and cortical areas in and around the posterior superior temporal sulcus (pSTS) region is employed in action understanding by vision and audition. However, the brain regions that are involved in action understanding by touch are unknown. Lederman et al. (2007) recently demonstrated that humans can haptically recognize facial expressions of emotion (FEE) surprisingly well. Here, we report a functional magnetic resonance imaging (fMRI) study in which we test the hypothesis that the IFG, IPL and pSTS regions are involved in haptic, as well as visual, FEE identification. Twenty subjects haptically or visually identified facemasks with three different FEEs (disgust, neutral and happiness) and casts of shoes (shoes) of three different types. The left posterior middle temporal gyrus, IPL, IFG and bilateral precentral gyrus were activated by FEE identification relative to that of shoes, regardless of sensory modality. By contrast, an inferomedial part of the left superior parietal lobule was activated by haptic, but not visual, FEE identification. Other brain regions, including the lingual gyrus and superior frontal gyrus, were activated by visual identification of FEEs, relative to haptic identification of FEEs. These results suggest that haptic and visual FEE identification rely on distinct but overlapping neural substrates including the IFG, IPL and pSTS region. PMID:19770059

  19. Functional MRI of food-induced brain responses

    OpenAIRE

    Smeets, P.A.M.

    2006-01-01

    The ultimate goal of this research was to find central biomarkers of satiety, i.e., physiological measures in the brain that relate to subjectively rated appetite, actual food intake, or both. This thesis describes the changes in brain activity in response to food stimuli as measured by functional MRI, with a focus on the hypothalamus. The hypothalamus is a brain area of particular interest because of its central role in the regulation of food intake. Two earlier studies showed that one long ...

  20. 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

  1. Manipulation of and sustained effects on the human brain induced by different modalities of acupuncture: an fMRI study.

    Directory of Open Access Journals (Sweden)

    Yin Jiang

    Full Text Available The javascript:void(0manipulation and sustained effects of acupuncture have been investigated in multiple studies, but several findings are inconsistent with one another. One possible explanation for these discrepancies is that different modalities of acupuncture were utilized in these studies. In the present study, we investigated both the manipulation and sustained effects of acupuncture in different modalities, including manual acupuncture (MA, electroacupuncture (EA and transcutaneous electrical acupoint stimulation (TEAS. MA, EA, TEAS and sensory control stimulation were applied to 18 healthy subjects, and combined block-designed and resting-state fMRI scans were performed. In analyzing these data, the block-designed datasets were used to assess the manipulation effect by employing a modified general linear model. The data from the resting states, before and after stimulation, were used to explore the brain networks involved in the sustained effect. The results showed that the two 1-min stimulation periods produced similar activation patterns in the sensory control with positive activation in the sensorimotor areas and negative activation in the default mode areas. Although similar patterns could be detected in the first stimulation period in MA, EA and TEAS, no positive activation result was observed in the second stimulation period, and EA showed a more extensive deactivation compared to MA and TEAS. Additionally, all three of the modalities of acupuncture stimulation could increase the instinct brain network in rest. A more secure and spatially extended connectivity of the default mode network was observed following MA and EA, and TEAS specifically increased the functional connectivity in the sensorimotor network. The present study suggested that different brain mechanisms might be recruited in different acupuncture modalities. In addition, the findings from our work could provide methodological information for further research into the

  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

    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....... A dual-echo pseudocontinuous arterial spin labeling (ASL) sequence was performed during normocapnic, hypercapnic, and hyperoxic breathing challenges. Whole brain and regional gray matter values of CBF, ASL cerebrovascular reactivity (CVR), BOLD CVR, oxygen extraction fraction (OEF), and CMRO2 were...... could potentially be explained by differences in EtCO2 . Regional CMRO2 was lower in older subjects. BOLD studies should take this into account when investigating age-related changes in neuronal activity....

  3. 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.

  4. 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.

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

    NARCIS (Netherlands)

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

    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

  6. 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.)

  7. Tracking brain arousal fluctuations with fMRI

    Science.gov (United States)

    Chang, Catie; Leopold, David A.; Schölvinck, Marieke Louise; Mandelkow, Hendrik; Picchioni, Dante; Liu, Xiao; Ye, Frank Q.; Turchi, Janita N.; Duyn, Jeff H.

    2016-01-01

    Changes in brain activity accompanying shifts in vigilance and arousal can interfere with the study of other intrinsic and task-evoked characteristics of brain function. However, the difficulty of tracking and modeling the arousal state during functional MRI (fMRI) typically precludes the assessment of arousal-dependent influences on fMRI signals. Here we combine fMRI, electrophysiology, and the monitoring of eyelid behavior to demonstrate an approach for tracking continuous variations in arousal level from fMRI data. We first characterize the spatial distribution of fMRI signal fluctuations that track a measure of behavioral arousal; taking this pattern as a template, and using the local field potential as a simultaneous and independent measure of cortical activity, we observe that the time-varying expression level of this template in fMRI data provides a close approximation of electrophysiological arousal. We discuss the potential benefit of these findings for increasing the sensitivity of fMRI as a cognitive and clinical biomarker. PMID:27051064

  8. MRI of the brain in diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Y. [Osaka Rosai Hospital (Japan). Dept. of Radiology; Nomurak, M. [Osaka Rosai Hospital (Japan). Dept. of Medicine; Tanaka, H. [Osaka Rosai Hospital (Japan). Dept. of Radiology; Yamamoto, H. [Osaka Rosai Hospital (Japan). Dept. of Radiology; Yamamoto, T. [Osaka Rosai Hospital (Japan). Dept. of Radiology; Tsukaguchi, I, [Osaka Rosai Hospital (Japan). Dept. of Radiology; Nakamura, H. [Osaka Univ. Medical School (Japan). Dept. of Radiology

    1994-02-01

    We studied the MRI appearances of the brain in 159 patients with diabetes mellitus (DM) and 2566 age-matched individuals without DM (controls). The images were reviewed for cerebral infarcts, hemorrhage, atrophy and subcortical arteriosclerotic encephalopathy. Cerebral atrophy was significantly more frequent in patients with DM than in controls (P > 0.005) from the sixth to the eighth decade. The frequency of atrophy was 41.2% in the 6th decade, 60.0 % in the 7th and 92.3 % in the 8th decade in DM, and 19.8 %, 38.9 % and 56.8 % respectively in controls. Unexpectedly, there was no statistically significant difference in the incidences of cerebrovascular diseases at any age. (orig.)

  9. MRI of the brain in diabetes mellitus

    International Nuclear Information System (INIS)

    We studied the MRI appearances of the brain in 159 patients with diabetes mellitus (DM) and 2566 age-matched individuals without DM (controls). The images were reviewed for cerebral infarcts, hemorrhage, atrophy and subcortical arteriosclerotic encephalopathy. Cerebral atrophy was significantly more frequent in patients with DM than in controls (P > 0.005) from the sixth to the eighth decade. The frequency of atrophy was 41.2% in the 6th decade, 60.0 % in the 7th and 92.3 % in the 8th decade in DM, and 19.8 %, 38.9 % and 56.8 % respectively in controls. Unexpectedly, there was no statistically significant difference in the incidences of cerebrovascular diseases at any age. (orig.)

  10. Structural and Perfusion Abnormalities of Brain on MRI and Technetium-99m-ECD SPECT in Children With Cerebral Palsy: A Comparative Study.

    Science.gov (United States)

    Rana, Kamer Singh; Narwal, Varun; Chauhan, Lokesh; Singh, Giriraj; Sharma, Monica; Chauhan, Suneel

    2016-04-01

    Cerebral palsy has traditionally been associated with hypoxic ischemic brain damage. This study was undertaken to demonstrate structural and perfusion brain abnormalities. Fifty-six children diagnosed clinically as having cerebral palsy were studied between 1 to 14 years of age and were subjected to 3 Tesla magnetic resonance imaging (MRI). Brain and Technetium-99m-ECD brain single-photon emission computed tomography (SPECT) scan. Male to female ratio was 1.8:1 with a mean age of 4.16 ± 2.274 years. Spastic cerebral palsy was the most common type, observed in 91%. Birth asphyxia was the most common etiology (69.6%). White matter changes (73.2%) such as periventricular leukomalacia and corpus callosal thinning were the most common findings on MRI. On SPECT all cases except one revealed perfusion impairments in different regions of brain. MRI is more sensitive in detecting white matter changes, whereas SPECT is better in detecting cortical and subcortical gray matter abnormalities of perfusion. PMID:26353878

  11. 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.

  12. MRI and MRS studies on acute effects of ethanol in the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Hirakawa, Keiko; Uekusa, Kyoko; Nihira, Makoto; Sato, Shigeru (Nippon Medical School, Tokyo (Japan))

    1994-04-01

    Using magnetic resonance (MR) imaging and MR spectroscopy, the effects of intoxicating doses of ethanol on the rat brain and the dynamic changes in the cerebral tissues were examined. After ethanol treatment, the cerebral hemispheres, especially the cortex, were shown as high signal intensities on T1-weighted images and low signal intensities on T2-weighted images. Four hr after ethanol treatment, the T1 values significantly decreased in the thalamus and hypothalamus, as compared with the control animals. At one hr, the T2 values significantly decreased in the cortex of the ethanol treated rats. At 4 and 24 hr, the T2 values significantly decreased in the cerebral hemispheres in the ethanol treated rats. In vivo [sup 31]P-MR spectroscopy showed a slight decrease in ATP and phosphocreatine after ethanol treatment. Intracellular pH levels decreased, but returned to normal by 4 hr. In highly sedated animals, early occurrence of acidosis was associated with heavy alkalosis. In vitro [sup 1]H-MR spectra of brain tissue and blood samples revealed many kinds of metabolites. Blood and brain levels of ethanol rose to the peak one 1 hr after ethanol treatment; and no ethanol was detected at 24 hr. Brain levels of acetate were almost unchanged. Blood levels of lactate significantly decreased at 0.5 hr; and brain levels of lactate slightly increased and rose to the peak at 2 hr. Brain N-acetylaspartic acid significantly increased at 0.5 hr and decreased at 4 hr. Electron microscopic findings were edema in both neuronal and glial cells after ethanol treatment, severe congestion, and swelling of mitochondria in capillary endothelial cells. In conclusion, high doses of ethanol may cause circulatory disorders in the rat brain and disturb water balance in the cerebral tissues, resulting in changes in the structure of intracellular water molecules. Ethanol also causes confusion without depletion of high energy phosphate metabolites. (N.K.) 44 refs.

  13. 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.

  14. Cortico-striato-thalamo-cortical circuit abnormalities in obsessive-compulsive disorder: A voxel-based morphometric and fMRI study of the whole brain.

    Science.gov (United States)

    Tang, Wenxin; Zhu, Qifeng; Gong, Xiangyang; Zhu, Cheng; Wang, Yiquan; Chen, Shulin

    2016-10-15

    The primary aim of this study was to identify structural and functional abnormalities in the brains of obsessive-compulsive disorder (OCD) patients. Another aim was to assess the effect of serotonin selective reuptake inhibitors (SSRIs) on brain structure of OCD patients. All subjects underwent brain magnetic resonance imaging (MRI) and resting functional MRI (fMRI). High-resolution three-dimensional images were processed using the voxel-based morphometry (VBM) method. The final analysis included 18 OCD patients and 16 healthy controls. In the OCD patients there was a decrease in gray matter volume in the bilateral cingulate cortex and bilateral striatum. In some cortical structures including the cerebellar anterior lobe, left orbital frontal gyrus, right middle frontal gyrus, left middle temporal gyrus, precentral gyrus, and postcentral gyrus, there was an increase in gray matter volume. On fMRI the OCD patients had overactivation of the right cerebellum and right parietal lobe and reduced activation of the left cingulate gyrus, putamen, and caudate nucleus. Eleven OCD patients who improved during 12 weeks of drug treatment with sertraline hydrochloride had a significant increase in gray matter volume in several brain structures but no significant differences were found on resting fMRI. The results indicated a consistent trend between structural and functional images. Higher cortical structures showed increased gray matter volume and increased activation as did the cerebellum whereas subcortical structures showed decreased gray matter volume and decreased activation. And brain structure improvement consisted with symptom improvement after SSRIs treatment in OCD patients. PMID:27388149

  15. 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

  16. Altered baseline brain activities before food intake in obese men: a resting state fMRI study.

    Science.gov (United States)

    Zhang, Bin; Tian, Derun; Yu, Chunshui; Zhang, Jing; Tian, Xiao; von Deneen, Karen M; Zang, Yufeng; Walter, Martin; Liu, Yijun

    2015-01-01

    Obesity as a chronic disease has become a global epidemic. However, why obese individuals eat more still remains unclear. Recent functional neuroimaging studies have found abnormal brain activations in obese people. In the present study, we used resting state functional MRI to observe spontaneous blood-oxygen-level dependent (BOLD) signal fluctuations during both hunger and satiety states in 20 lean and 20 obese men. Using a regional homogeneity (ReHo) analysis method, we measured temporal homogeneity of the regional BOLD signals. We found that, before food intake, obese men had significantly increased synchronicity of activity in the left putamen relative to lean men. Decreased synchronicity of activity was found in the orbitofrontal cortex (OFC) and medial prefrontal cortex(MPFC) in the obese subjects. And, the ratings of hunger of the obese subjects were higher than those of the lean subjects before food intake. After food intake, we did not find the significant differences between the obese men and the lean men. In all participations, synchronicity of activity increased from the fasted to the satiated state in the OFC. The results indicated that OFC plays an important role in feeding behavior, and OFC signaling may be disordered in obesity. Obese men show less inhibitory control during fasting state. This study has provided strong evidence supporting the hypothesis that there is a hypo-functioning reward circuitry in obese individuals, in which the frontal cortex may fail to inhibit the striatum, and consequently lead to overeating and obesity. PMID:25459293

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

    OpenAIRE

    Ahmad Saeed Rajab; Crane, David E.; Middleton, Laura E; Andrew eRobertson; Michelle eHampson; Bradley J MacIntosh

    2014-01-01

    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 healt...

  18. 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.

  19. 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.

  20. MRI or not to MRI! Should brain MRI be a routine investigation in children with autistic spectrum disorders?

    Science.gov (United States)

    Zeglam, Adel M; Al-Ogab, Marwa F; Al-Shaftery, Thouraya

    2015-09-01

    To evaluate the routine usage of Magnetic Resonance Imaging (MRI) of brain and estimate the prevalence of brain abnormalities in children presenting to the Neurodevelopment Clinic of Al-Khadra Hospital (NDC-KH), Tripoli, Libya with autistic spectrum disorders (ASD). The records of all children with ASD presented to NDC-KH over 4-year period (from January 2009 to December 2012) were reviewed. All MRIs were acquired with a 1.5-T Philips (3-D T1, T2, FLAIR coronal and axial sequences). MRIs were reported to be normal, abnormal or no significant abnormalities by a consultant neuroradiologist. One thousand and seventy-five children were included in the study. Seven hundred and eighty-two children (72.7 %) had an MRI brain of whom 555 (71 %) were boys. 26 children (24 males and 2 females) (3.3 %) demonstrated MRI abnormalities (8 leukodystrophic changes, 4 periventricular leukomalacia, 3 brain atrophy, 2 tuberous sclerosis, 2 vascular changes, 1 pineoblastoma, 1 cerebellar angioma, 1 cerebellar hypoplasia, 3 agenesis of corpus callosum, 1 neuro-epithelial cyst). An unexpectedly high rate of MRI abnormalities was found in the first large series of clinical MRI investigations in children with autism. These results could contribute to further research into the pathogenesis of autistic spectrum disorder. PMID:25344829

  1. 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.

  2. 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.

  3. 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.

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

    International Nuclear Information System (INIS)

    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

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    a dissociable role between these regions in the reward processing of expertise. Finally, categorical responses (irrespective of aesthetic ratings) resulted in expertise effects in memory-related areas such as hippocampus and precuneus. These results highlight the fact that expertise not only modulates cognitive...... 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...

  6. 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

  7. 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.

  8. Fetal MRI of pathological brain development

    International Nuclear Information System (INIS)

    Because of the superior tissue contrast, high spatial resolution, and multiplanar capabilities, fetal magnetic resonance imaging (MRI) can depict fetal brain pathologies with high accuracy. Pathological fetal brain development may result from malformations or acquired conditions. Differentiation of these etiologies is important with respect to managing the actual pregnancy or counseling future pregnancies. As a widened ventricular system is a common hallmark of both maldevelopment and acquired conditions, it may cause problems in the differential diagnosis. Fetal MRI can provide detailed morphological information, which allows refinement of the diagnosis of ventricular enlargement in a large number of cases. Systematic work-up of morphological details that may be recognized on MR images provides an approach for achieving a correct diagnosis in cases of ventricle enlargement. (orig.)

  9. 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.

  10. Brain MRI findings of neuropsychiatric lupus

    International Nuclear Information System (INIS)

    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

  11. 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.

  12. Changes in Alcohol-Related Brain Networks Across the First Year of College: A Prospective Pilot Study Using fMRI Effective Connectivity Mapping

    OpenAIRE

    Adriene M. Beltz; Gates, Kathleen M.; Engels, Anna S.; Molenaar, Peter C. M.; Pulido, Carmen; Turrisi, Robert; Sheri A. Berenbaum; Gilmore, Rick O.; Wilson, Stephen J.

    2013-01-01

    The upsurge in alcohol use that often occurs during the first year of college has been convincingly linked to a number of negative psychosocial consequences and may negatively affect brain development. In this longitudinal functional magnetic resonance imaging (fMRI) pilot study, we examined changes in neural responses to alcohol cues across the first year of college in a normative sample of late adolescents. Participants (N=11) were scanned three times across their first year of college (sum...

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

    OpenAIRE

    Rajab, Ahmad S.; Crane, David E.; Middleton, Laura E; Robertson, Andrew D.; Hampson, Michelle; Bradley J MacIntosh

    2014-01-01

    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 functional magnetic resonance imaging (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 func...

  14. Brain perfusion in dementia with Lewy bodies and Alzheimer’s disease: an arterial spin labeling MRI study on prodromal and mild dementia stages

    OpenAIRE

    Roquet, Daniel; Sourty, Marion; Botzung, Anne; Armspach, Jean-Paul; Blanc, Frédéric

    2016-01-01

    Background We aimed to describe specific changes in brain perfusion in patients with dementia with Lewy bodies (DLB) at both the prodromal (also called mild cognitive impairment) and mild dementia stages, relative to patients with Alzheimer’s disease (AD) and controls. Methods Altogether, 96 participants in five groups (prodromal DLB, prodromal AD, DLB with mild dementia, AD with mild dementia, and healthy elderly controls) took part in an arterial spin labeling MRI study. Three analyses were...

  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. Sex differences in the risk profile and male predominance in silent brain infarction in community-dwelling elderly subjects. The Sefuri brain MRI study

    International Nuclear Information System (INIS)

    Although brain infarction is more common in men, the male predominance of silent brain infarction (SBI) was inconsistent in the earlier studies. This study was to examine the relationship between sex differences in the risk profile and SBI. We conducted a population-based, cross-sectional analysis of cardiovascular risk factors and SBI on MRI. We asked all the female participants about the age at natural menopause and parity. SBI was detected in 77 (11.3%) of 680 participants (266 men and 414 women) with a mean age of 64.5 (range 40-93) years. In the logistic analysis, age (odds ratio (OR)=2.760/10 years, 95% confidence interval (CI)=2.037-3.738), hypertension (OR=3.465, 95% CI=1.991-6.031), alcohol intake (OR=2.494, 95% CI=1.392-4.466) and smoking (OR=2.302, 95% CI=1.161-4.565) were significant factors concerning SBI. Although SBI was more prevalent among men, this sex difference disappeared on the multivariate model after adjustment for other confounders. In 215 women aged 60 years or older, age at natural menopause, early menopause, duration of menopause, number of children and age at the last parity were not significantly associated with SBI after adjustment for age. Hypertension and age were considered to be the major risk factors for SBI in community-dwelling people. Male predominance in SBI was largely due to higher prevalence of alcohol habit and smoking in men than in women in our population. (author)

  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. 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.

  19. Lateralization of Brain Networks and Clinical Severity in Toddlers with Autism Spectrum Disorder: A HARDI Diffusion MRI Study.

    Science.gov (United States)

    Conti, Eugenia; Calderoni, Sara; Gaglianese, Anna; Pannek, Kerstin; Mazzotti, Sara; Rose, Stephen; Scelfo, Danilo; Tosetti, Michela; Muratori, Filippo; Cioni, Giovanni; Guzzetta, Andrea

    2016-03-01

    Recent diffusion tensor imaging studies in adolescents and children with Autism Spectrum Disorder (ASD) have reported a loss or an inversion of the typical left-right lateralization in fronto-temporal regions crucial for sociocommunicative skills. No studies explored atypical lateralization in toddlers and its correlation with clinical severity of ASD. We recruited a cohort of 20 subjects aged 36 months or younger receiving a first clinical diagnosis of ASD (15 males; age range 20-36 months). Patients underwent diffusion MRI (High-Angular-Resolution Diffusion Imaging protocol). Data from cortical parcellation were combined with tractography to obtain a connection matrix and diffusion indexes (DI ) including mean fractional anisotropy (DFA ), number of tracts (DNUM ), and total tract length (DTTL ). A laterality index was generated for each measure, and then correlated with the Autism Diagnostic Observation Schedule-Generic (ADOS-G) total score. Laterality indexes of DFA were significantly correlated with ADOS-G total scores only in two intrafrontal connected areas (correlation was positive in one case and negative in the other). Laterality indexes of DTTL and DNUM showed significant negative correlations (P < 0.05) in six connected areas, mainly fronto-temporal. This study provides first evidence of a significant correlation between brain lateralization of diffusion indexes and clinical severity in toddlers with a first diagnosis of ASD. Significant correlations mainly involved regions within the fronto-temporal circuits, known to be crucial for sociocommunicative skills. It is of interest that all correlations but one were negative, suggesting an inversion of the typical left-right asymmetry in subjects with most severe clinical impairment. PMID:26280255

  20. Indices of adrenal deficiency involved in brain plasticity and functional control reorganization in hemodialysis patients with polysulfone membrane: BOLD-fMRI study.

    Science.gov (United States)

    Belaïch, Rachida; Boujraf, Saïd; Benzagmout, Mohammed; Maaroufi, Mustapha; Housni, Abdelkhalek; Batta, Fatima; Tizniti, Siham; Magoul, Rabia; Sqalli, Tarik

    2016-06-01

    This work purpose was to estimate the implication of suspected adrenal function deficiencies, which was influenced by oxidative stress (OS) that are generating brain plasticity, and reorganization of the functional control. This phenomenon was revealed in two-hemodialysis patients described in this paper. Blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) revealed a significant activation of the motor cortex. Hemodialysis seems to originate an inflammatory state of the cerebral tissue reflected by increased OS, while expected to decrease since hemodialysis eliminates free radicals responsible for OS. Considering adrenal function deficiencies, sensitivity to OS and assessed hyponatremia and hypercalcemia, adrenal function deficiencies is strongly suspected in both patients. This probably contributes to amplify brain plasticity and a reorganization of functional control after hemodialysis that is compared to earlier reported studies. Brain plasticity and functional control reorganization was revealed by BOLD-fMRI with a remarkable sensitivity. Brain plastic changes are originated by elevated OS associating indices of adrenal function deficiencies. These results raise important issues about adrenal functional deficiencies impact on brain plasticity in chronic hemodialysis-patients. This motivates more global studies of plasticity induced factors in this category of patients including adrenal functional deficiencies and OS. PMID:27301905

  1. 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.)

  2. 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

    2016-11-01

    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.

  3. Intraoperative MRI in pediatric brain tumors

    International Nuclear Information System (INIS)

    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. 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.)

  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. A functional MRI study of the brain in stroke patients with upper-limb paralysis treated with constraint-induced movement therapy

    International Nuclear Information System (INIS)

    Objective: To investigate and compare the activation patterns of stroke patients with upper-limb paralysis using functional MRI before and after treatment with constraint-induced movement therapy (CIMT) so as to explore the mechanism of CIMT. Methods: Six patients in chronic stage of brain infarction who have functional disturbance in right upper-limb and 9 normal controls were entered into the study. All of the patients were asked to perform the thumb-to-index finger tapping task and underwent functional MRI before and two weeks after CIMT. The controls underwent fMRI of same protocol once. The patients' upper-limb function scores before and after CIMT were analyzed with SPSS 11.5 by paired t test. The fMRI data were analyzed with analysis of functional neurolmages (AFNI) software. The percentage of blood oxygenation level dependent (BOLD) signal change for the normal control was analyzed by one-sample t test to indentify the activated brain regions. The percentage change of BOLD signal for the patients before and after CIMT was compared to control's data by independent-samples t test. The percentage change of BOLD signal for the patients before and after CIMT was analyzed by paired-samples t test. The significant difference level was set P<0.05. Results: The fMRI showed the patients' activated brain regions before CIMT were similar to that of the controls', while the activation level was lower. There were wide areas activated to compensate the impaired function especially for the fight upper-limb. Before CIMT, the patients' score for fight upper-limb on the action research arm test was 27±4. After CIMT, the patients' score was 40±3, and the difference was significant (t=14.626, P<0.05), which indicated the improved function. These subjects also displayed cortical reorganization after CIMT on fMRI. The areas responsible for the right hand movement showed increased activation and the activation level at bilateral corpora striata thalami, and cerebella increased

  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. False recognition of emotional stimuli is lateralised in the brain: An fMRI study.

    Science.gov (United States)

    Marchewka, A; Brechmann, A; Nowicka, A; Jednoróg, K; Scheich, H; Grabowska, A

    2008-07-01

    We have investigated whether the left (LH) and right (RH) hemisphere play a different role in eliciting false recognition (FR) and whether their involvement in this memory illusion depends on the emotional content of stimuli. Negative and neutral pictures (taken from IAPS) were presented in the divided-visual field paradigm. Subjects task was to indicate whether the pictures had already been presented or not during the preceding study phase. FR rate was much higher for the RH than the LH presentations. In line, FR resulted in activations mainly in the right prefrontal cortex (PFC) for either RH or LH presentations. Emotional content of stimuli facilitated the formation of false memories and strengthened the involvement of the right PFC in FR induction. PMID:18329298

  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. 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 < 0.001). Even after adjustment for age, in the patients, being younger than the controls (p < 0.05), every offender type group displayed a higher proportion of subjects with brain regions categorized as definitely abnormal than the non-criminal controls. Within the forensic inpatients, offense type groups did not significantly differ in brain 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

  14. Review of methods for functional brain connectivity detection using fMRI

    OpenAIRE

    Li, Kaiming; Guo, Lei; Nie, Jingxin; Li, Gang; Liu, Tianming

    2008-01-01

    Since the mid of 1990s, functional connectivity study using fMRI (fcMRI) has drawn increasing attention of neuroscientists and computer scientists, since it opens a new window to explore functional network of human brain with relatively high resolution. A variety of methods for fcMRI study have been proposed. This paper intends to provide a technical review on computational methodologies developed for fcMRI analysis. From our perspective, these computational methods are classified into two ge...

  15. The effect of alcohol consumption on the adolescent brain: A systematic review of MRI and fMRI studies of alcohol-using youth

    Directory of Open Access Journals (Sweden)

    Sarah W. Feldstein Ewing

    2014-01-01

    Conclusions: Alcohol consumption during adolescence was associated with significant differences in structure and function in the developing human brain. However, this is a nascent field, with several limiting factors (including small sample sizes, cross-sectional designs, presence of confounding factors within many of the reviewed studies, meaning that results should be interpreted in light of the preliminary state of the field. Future longitudinal and large-scale studies are critical to replicate the existing findings, and to provide a more comprehensive and conclusive picture of the effect of alcohol consumption on the developing brain.

  16. 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.

  17. 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.)

  18. Neuropsychological deficits and morphological MRI brain scan abnormalities in apparently health non-encephalopathic patients with cirrhosis; A controlled Study

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.W.; De Lacey, G.; Dunk, A.A.; Sinclair, T.S.; Mowat, M.A.G.; Brunt, P.W. (Royal Infirmary, Aberdeen (United Kingdom)); Deans, H. (Aberdeen Univ. (UK). Dept. of Medical Physics (United Kingdom)); Crawford, J.R. (Aberdeen University Medical School (United Kingdom). Department of Psychology (United Kingdom)); Besson, J.A.O. (Aberdeen University Medical School (United Kingdom). Department of Mental Health (United Kingdom))

    1989-11-01

    By means of psychometric testing, we have determined the frequency of latent hepatic encephalopathy in a group of 19 cirrhotics with no clinical evidence of encephalopathy. Magnetic resonance imaging (MRI) of the brain was performed in order to determine whether morphological cerebral abnormalities were associated with latent encephalopathy. Nineteen age and educationally matched patient with normal liver function acted as controls. Significant differences (P < 0.05) between cirrhotics and controls were found in tests of short-term visual memory and speed of reaction to light (cirrhotics 326 ( 132 ms vs. controls 225 ) 36 ms), sound (cirrhotics 361 ( 152 ms vs. controls 236 ) 52 ms) and choice (cirrhotics 651 ( 190 ms vs. controls 406 ) 101 ms) stimuli (all values mean S.D.). Reitan trail test performance, however, was similar in both groups. ( Trail A: cirrhotics 43 ( 19 s vs. controls 35 ) 13 s; Trail B: cirrhotics 105 ( 66 s vs. controls 93 ) 36 s.) In patients with cirrhosis, MRI revealed statistically significant increases in the maximum fissure width of right frontal sulci, light and left parietal sulci, inter-hemispheric fissure width and in bicaudafe index. These changes, indicating cerebral atrophy, were largely confined to alcoholics. There was poor correlation between measurements of cerebral morphology and neuropsychological performance, only 10% of associations achieving statistical significance. (author). 2 refs.; 3 figs.; 5 tabs.

  19. 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.

  20. 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

    MRI and PET provide complementary information for studying brain function. While the potential use of simultaneous MRI/PET for clinical diagnostic and disease staging has been demonstrated recently; the biological relevance of concurrent functional MRI-PET brain imaging to dissect neurochemically...... and striatum related to pain processing, while modality specific brain networks were also found. Co-localized fMRI and PET signal changes in the thalamus were positively correlated suggesting that pain-induced changes in opioid neurotransmission contribute a significant component of the fMRI signal...... change 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....

  1. 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...

  2. 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.

  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. 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.

  6. 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

  7. 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.

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

    OpenAIRE

    Kristian Tylen; Andreas Roepstorff

    2012-01-01

    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 m...

  9. Interaction vs. observation:distinctive modes of social cognition in human brain and behavior? A combined fMRI and eye-tracking study

    OpenAIRE

    Tylén, Kristian; Allen, Micah; Hunter, Bjørk K.; Roepstorff, Andreas

    2012-01-01

    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 m...

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

    Science.gov (United States)

    Rajab, Ahmad S; Crane, David E; Middleton, Laura E; Robertson, Andrew D; Hampson, Michelle; MacIntosh, Bradley J

    2014-01-01

    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 functional magnetic resonance imaging (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 min of moderate intensity aerobic exercise and compared this with a no-exercise control group (N = 15). Data were analyzed using independent component analysis, denoising and dual regression procedures. Regions of interest-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 effect of session in these three RSNs (pexercise 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. PMID:25177284

  11. A correlation of clinical, MRI and brain SPECT in dementia

    International Nuclear Information System (INIS)

    Background: Dementia is a clinical syndrome characterised by acquired impairment in multiple neuropsycologic and behavior domains including memory, language, speech, visuospatial ability, cognition and mood/personality. Dementia produces deficits in perfusion reflecting decreased metabolic needs. Neuroimaging techniques help in determining whether the cognitive symptoms are organic and in which pattern of cognitive loss the patient may evolve. AIM: To differentiate various types of Dementia, based on the regional perfusion abnormalities seen in Brain SPECT and correlate this with Clinical and MRI findings. Material and methods: Patients suffering from memory impairment and memory loss were referred to our department for Brain SPECT as a part of work up for Dementia. They had undergone a detailed clinical examination, psychometry, mini mental status examination (MMSE), memory/cognitive testing and an MRI. Brain SPECT was done after injecting Tc 99m ECD (Ethylene Cysteinate Dimer ) and imaging after 45 minutes. The images obtained were reconstructed in a conventional way. The various patterns of perfusion abnormalities seen in the SPECT images was studied and correlated with MRI and clinical findings. The patients were thus classified as having Multi Infarct Dementia, Alzheimer's disease, Fronto-Temporal Dementia and Mixed variety. Results: Twenty One Patients were included in our study from February 2003 to February 2004. The mean age of the patients was 73 years ( 37 to 81). 15 were males and 6 were females. Out of 21 patients, 12 had Multi Infarct Dementia, 4 had Alzheimer's disease, 1 had Fronto- Temporal Dementia and 4 had Mixed variety. Conclusion: Brain SPECT aids in substantiating the clinical findings and in correlation with MRI helps in distinguishing various types of Dementia and thus has prognostic implications and helps in instituting early appropriate treatment to the patient. In our study, the majority of the patients have Multi Infarct Dementia

  12. CT and MRI imaging of the brain in MELAS syndrome

    International Nuclear Information System (INIS)

    MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes) is a rare, multisystem disorder which belongs to a group of mitochondrial metabolic diseases. As other diseases in this group, it is inherited in the maternal line. In this report, we discussed a case of a 10-year-old girl with clinical and radiological picture of MELAS syndrome. We would like to describe characteristic radiological features of MELAS syndrome in CT, MRI and MR spectroscopy of the brain and differential diagnosis. The rarity of this disorder and the complexity of its clinical presentation make MELAS patients among the most difficult to diagnose. Brain imaging studies require a wide differential diagnosis, primarily to distinguish between MELAS and ischemic stroke. Particularly helpful are the MRI and MR spectroscopy techniques

  13. 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.

  14. 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.

  15. 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

  16. 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.)

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

    International Nuclear Information System (INIS)

    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.)

  18. Value of brain MRI in infective endocarditis: a narrative literature review.

    Science.gov (United States)

    Champey, J; Pavese, P; Bouvaist, H; Kastler, A; Krainik, A; Francois, P

    2016-02-01

    The nervous system is frequently involved in patients with infective endocarditis (IE). A systematic review of the literature was realized in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). This study sought to systematically evaluate the published evidence of the contribution of brain magnetic resonance imaging (MRI) in IE. The aim was to identify studies presenting the incidence and type of MRI brain lesions in IE. Fifteen relevant studies were isolated using the Medline, Embase, and Cochrane databases. Most of them were observational studies with a small number of patients. MRI studies demonstrated a wide variety and high frequency of cerebral lesions, around 80 % of which were mostly clinically occult. This review shows MRI's superiority compared to brain computed tomography (CT) for the diagnosis of neurologic complications. Recent developments of sensitive MRI sequences can detect microinfarction and cerebral microhemorrhages. However, the clinical significance of these microhemorrhages, also called cerebral microbleeds (CMBs), remains uncertain. Because some MRI neurological lesions are a distinctive IE feature, they can have a broader involvement in diagnosis and therapeutic decisions. Even if cerebral MRI offers new perspectives for better IE management, there is not enough scientific proof to recommend it in current guidelines. The literature remains incomplete regarding the impact of MRI on concerted decision-making. The long-term prognosis of CMBs has not been evaluated to date and requires further studies. Today, brain MRI can be used on a case-by-case basis based on a clinician's appraisal. PMID:26585337

  19. 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.)

  20. 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

  1. Brain microstructure mapping using quantitative and diffusion MRI

    International Nuclear Information System (INIS)

    This thesis is focused on the human brain microstructure mapping using quantitative and diffusion MRI. The T1/T2 quantitative imaging relies on sequences dedicated to the mapping of T1 and T2 relaxation times. Their variations within the tissue are linked to the presence of different water compartments defined by a specific organization of the tissue at the cell scale. Measuring these parameters can help, therefore, to better characterize the brain microstructure. The dMRI, on the other hand, explores the brownian motion of water molecules in the brain tissue, where the water molecules' movement is constrained by natural barriers, such as cell membranes. Thus, the information on their displacement carried by the dMRI signal gives access to the underlying cyto-architecture. Combination of these two modalities is, therefore, a promising way to probe the brain tissue microstructure. The main goal of the present thesis is to set up the methodology to study the microstructure of the white matter of the human brain in vivo. The first part includes the acquisition of a unique MRI database of 79 healthy subjects (the Archi/CONNECT), which includes anatomical high resolution data, relaxometry data, diffusion-weighted data at high spatio-angular resolution and functional data. This database has allowed us to build the first atlas of the anatomical connectivity of the healthy brain through the automatic segmentation of the major white matter bundles, providing an appropriate anatomical reference for the white matter to study individually the quantitative parameters along each fascicle, characterizing its microstructure organization. Emphasis was placed on the construction of the first atlas of the T1/T2 profiles along the major white matter pathways. The profiles of the T1 and T2 relaxation times were then correlated to the quantitative profiles computed from the diffusion MRI data (fractional anisotropy, radial and longitudinal diffusivities, apparent diffusion coefficient

  2. Multidimensional Brain MRI segmentation using graph cuts

    International Nuclear Information System (INIS)

    This thesis deals with the segmentation of multimodal brain MRIs by graph cuts method. First, we propose a method that utilizes three MRI modalities by merging them. The border information given by the spectral gradient is then challenged by a region information, given by the seeds selected by the user, using a graph cut algorithm. Then, we propose three enhancements of this method. The first consists in finding an optimal spectral space because the spectral gradient is based on natural images and then inadequate for multimodal medical images. This results in a learning based segmentation method. We then explore the automation of the graph cut method. Here, the various pieces of information usually given by the user are inferred from a robust expectation-maximization algorithm. We show the performance of these two enhanced versions on multiple sclerosis lesions. Finally, we integrate atlases for the automatic segmentation of deep brain structures. These three new techniques show the adaptability of our method to various problems. Our different segmentation methods are better than most of nowadays techniques, speaking of computation time or segmentation accuracy. (authors)

  3. 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.

  4. 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…

  5. 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.

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

    OpenAIRE

    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.

    2012-01-01

    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 ...

  7. Motor Network Plasticity and Low-Frequency Oscillations Abnormalities in Patients with Brain Gliomas: A Functional MRI Study

    Science.gov (United States)

    Niu, Chen; Zhang, Ming; Min, Zhigang; Rana, Netra; Zhang, Qiuli; Liu, Xin; Li, Min; Lin, Pan

    2014-01-01

    Brain plasticity is often associated with the process of slow-growing tumor formation, which remodels neural organization and optimizes brain network function. In this study, we aimed to investigate whether motor function plasticity would display deficits in patients with slow-growing brain tumors located in or near motor areas, but who were without motor neurological deficits. We used resting-state functional magnetic resonance imaging to probe motor networks in 15 patients with histopathologically confirmed brain gliomas and 15 age-matched healthy controls. All subjects performed a motor task to help identify individual motor activity in the bilateral primary motor cortex (PMC) and supplementary motor area (SMA). Frequency-based analysis at three different frequencies was then used to investigate possible alterations in the power spectral density (PSD) of low-frequency oscillations. For each group, the average PSD was determined for each brain region and a nonparametric test was performed to determine the difference in power between the two groups. Significantly reduced inter-hemispheric functional connectivity between the left and right PMC was observed in patients compared with controls (P<0.05). We also found significantly decreased PSD in patients compared to that in controls, in all three frequency bands (low: 0.01–0.02 Hz; middle: 0.02–0.06 Hz; and high: 0.06–0.1 Hz), at three key motor regions. These findings suggest that in asymptomatic patients with brain tumors located in eloquent regions, inter-hemispheric connection may be more vulnerable. A comparison of the two approaches indicated that power spectral analysis is more sensitive than functional connectivity analysis for identifying the neurological abnormalities underlying motor function plasticity induced by slow-growing tumors. PMID:24806463

  8. Motor network plasticity and low-frequency oscillations abnormalities in patients with brain gliomas: a functional MRI study.

    Directory of Open Access Journals (Sweden)

    Chen Niu

    Full Text Available Brain plasticity is often associated with the process of slow-growing tumor formation, which remodels neural organization and optimizes brain network function. In this study, we aimed to investigate whether motor function plasticity would display deficits in patients with slow-growing brain tumors located in or near motor areas, but who were without motor neurological deficits. We used resting-state functional magnetic resonance imaging to probe motor networks in 15 patients with histopathologically confirmed brain gliomas and 15 age-matched healthy controls. All subjects performed a motor task to help identify individual motor activity in the bilateral primary motor cortex (PMC and supplementary motor area (SMA. Frequency-based analysis at three different frequencies was then used to investigate possible alterations in the power spectral density (PSD of low-frequency oscillations. For each group, the average PSD was determined for each brain region and a nonparametric test was performed to determine the difference in power between the two groups. Significantly reduced inter-hemispheric functional connectivity between the left and right PMC was observed in patients compared with controls (P<0.05. We also found significantly decreased PSD in patients compared to that in controls, in all three frequency bands (low: 0.01-0.02 Hz; middle: 0.02-0.06 Hz; and high: 0.06-0.1 Hz, at three key motor regions. These findings suggest that in asymptomatic patients with brain tumors located in eloquent regions, inter-hemispheric connection may be more vulnerable. A comparison of the two approaches indicated that power spectral analysis is more sensitive than functional connectivity analysis for identifying the neurological abnormalities underlying motor function plasticity induced by slow-growing tumors.

  9. [An fMRI Study of the Brain Activation Related to Intensive Positive Emotions During Viweing Erotic Pictures in 49-74 Old Men].

    Science.gov (United States)

    Martynova, O; Portnova, G; Orlov, I

    2016-01-01

    According to psychological research erotic images are evaluated in the context of positive emotions as the most intense, most associated with emotional arousal, among the variety of pleasant and unpleasant stimuli. However it is difficult to separate areas of the brain that are related to the general emotional process from the activity of the brain areas involved in neuronal representations of reward system. The purpose of this study was to determine differences in the brain activity using functional magnetic resonance imaging (fMRI) in male subjects in evaluating an intensity of pleasant images, including erotic, or unpleasant and neutral pictures. When comparing the condition with evaluation of the pleasant erotic images with conditions containing neutral or unpleasant stimuli, a significant activation was observed in the posterior cingulate cortex; the prefrontal cortex and the right globus pallidus. An increased activity of the right anterior central gyrus was observed in the conditions related to evaluation of pleasant and neutral stimuli. Thus, in the process of evaluating the intensity of emotional images of an erotic nature the active brain areas were related not only to neuronal representations of emotions, but also to motivations and control system of emotional arousal, which should be taken into account while using erotic pictures as intensive positive emotional stimuli. PMID:27263273

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. Disrupted brain network topology in pediatric posttraumatic stress disorder: A resting-state fMRI study.

    Science.gov (United States)

    Suo, Xueling; Lei, Du; Li, Kaiming; Chen, Fuqin; Li, Fei; Li, Lei; Huang, Xiaoqi; Lui, Su; Li, Lingjiang; Kemp, Graham J; Gong, Qiyong

    2015-09-01

    Children exposed to natural disasters are vulnerable to the development of posttraumatic stress disorder (PTSD). Recent studies of other neuropsychiatric disorders have used graph-based theoretical analysis to investigate the topological properties of the functional brain connectome. However, little is known about this connectome in pediatric PTSD. Twenty-eight pediatric PTSD patients and 26 trauma-exposed non-PTSD patients were recruited from 4,200 screened subjects after the 2008 Sichuan earthquake to undergo a resting-state functional magnetic resonance imaging scan. Functional connectivity between 90 brain regions from the automated anatomical labeling atlas was established using partial correlation coefficients, and the whole-brain functional connectome was constructed by applying a threshold to the resultant 90 * 90 partial correlation matrix. Graph theory analysis was then used to examine the group-specific topological properties of the two functional connectomes. Both the PTSD and non-PTSD control groups exhibited "small-world" brain network topology. However, the functional connectome of the PTSD group showed a significant increase in the clustering coefficient and a normalized characteristic path length and local efficiency, suggesting a shift toward regular networks. Furthermore, the PTSD connectomes showed both enhanced nodal centralities, mainly in the default mode- and salience-related regions, and reduced nodal centralities, mainly in the central-executive network regions. The clustering coefficient and nodal efficiency of the left superior frontal gyrus were positively correlated with the Clinician-Administered PTSD Scale. These disrupted topological properties of the functional connectome help to clarify the pathogenesis of pediatric PTSD and could be potential biomarkers of brain abnormalities. PMID:26096541

  15. 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.

  16. 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

  17. Advanced Structural and Functional Brain MRI in Multiple Sclerosis.

    Science.gov (United States)

    Giorgio, Antonio; De Stefano, Nicola

    2016-04-01

    Conventional magnetic resonance imaging (MRI) of the central nervous system is crucial for an early and reliable diagnosis and monitoring of patients with multiple sclerosis (MS). Focal white matter (WM) lesions, as detected by MRI, are the pathological hallmark of the disease and show some relation to clinical disability, especially in the long run. Gray matter (GM) involvement is evident from disease onset and includes focal (i.e., cortical lesions) and diffuse pathology (i.e., atrophy). Both accumulate over time and show close relation to physical disability and cognitive impairment. Using advanced quantitative MRI techniques such as magnetization transfer imaging (MTI), diffusion tensor imaging (DTI), proton MR spectroscopy ((1)H-MRS), and iron imaging, subtle MS pathology has been demonstrated from early stages outside focal WM lesions in the form of widespread abnormalities of the normal appearing WM and GM. In addition, studies using functional MRI have demonstrated that brain plasticity is driven by MS pathology, playing adaptive or maladaptive roles to neurologic and cognitive status and explaining, at least in part, the clinicoradiological paradox of MS. PMID:27116723

  18. 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.

  19. The role of diffusion-weighted MRI on the study of brain complications related to heroin abuse

    Directory of Open Access Journals (Sweden)

    Yasamin Daoudi

    2015-06-01

    Full Text Available Heroin has physical effects on many parts of the body, for example, respiratory and digestive system, muscles, and nervous system. Neurologic complications include brain abscess, neuropathy, transverse myelitis, and leukoencephalopathy.Magnetic resonance image is more sensitive in detecting lesions with low signal on T1W and high signal on T2W, and FLAIR images in the white matter and other areas of brain. Imaging findings are similar to other leukoencephalopathies (hereditary diseases, abnormal metabolic diseases, and intoxications.In the course of finding ways to differentiate heroin-induced spongiform leukoencephalopathy from other leukoencephalopathies, attention has been changed to diffusion magnetic resonance imaging in recent years.Nevertheless, studies do not verify that diffusion-weighted image is a valuable tool in establishing the diagnosis.

  20. 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.

  1. Decreased Regional Homogeneity in Patients With Acute Mild Traumatic Brain Injury: A Resting-State fMRI Study.

    Science.gov (United States)

    Zhan, Jie; Gao, Lei; Zhou, Fuqing; Kuang, Hongmei; Zhao, Jing; Wang, Siyong; He, Laichang; Zeng, Xianjun; Gong, Honghan

    2015-10-01

    Mild traumatic brain injury (mTBI) is characterized by structural disconnection and large-scale neural network dysfunction in the resting state. However, little is known concerning the intrinsic changes in local spontaneous brain activity in patients with mTBI. The aim of the current study was to assess regional synchronization in acute mTBI patients. Fifteen acute mTBI patients and 15 sex-, age-, and education-matched healthy controls (HCs) were studied. We used the regional homogeneity (ReHo) method to map local connectivity across the whole brain and performed a two-sample t-test between the two groups. Compared with HCs, patients with acute mTBI showed significantly decreased ReHo in the left insula, left precentral/postcentral gyrus, and left supramarginal gyrus (p Mental State Examination (MMSE) scores across all acute mTBI patients (p < 0.05, uncorrected). The ReHo method may provide an objective biomarker for evaluating the functional abnormity of mTBI in the acute setting. PMID:26348589

  2. 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.)

  3. Atlas of regional anatomy of the brain using MRI. With functional correlations

    International Nuclear Information System (INIS)

    The volume provides a unique review of the essential topographical anatomy of the brain from an MRI perspective, correlating high-quality anatomical plates with the corresponding high-resolution MRI images. The book includes a historical review of brain mapping and an analysis of the essential reference planes used for the study of the human brain. Subsequent chapters provide a detailed review of the sulcal and the gyral anatomy of the human cortex, guiding the reader through an interpretation of the individual brain atlas provided by high-resolution MRI. The relationship between brain structure and function is approached in a topographical fashion with analysis of the necessary imaging methodology and displayed anatomy. The central, perisylvian, mesial temporal and occipital areas receive special attention. Imaging of the core brain structures is included. An extensive coronal atlas concludes the book. (orig.)

  4. 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.

  5. Brain Activity in Response to Trauma-specific, Negative, and Neutral Stimuli. A fMRI Study of Recent Road Traffic Accident Survivors

    Science.gov (United States)

    Nilsen, Andre S.; Blix, Ines; Leknes, Siri; Ekeberg, Øivind; Skogstad, Laila; Endestad, Tor; Østberg, Bjørn C.; Heir, Trond

    2016-01-01

    Most studies of neuro-functional patterns in trauma-exposed individuals have been conducted considerable time after the traumatic event. Hence little is known about neuro-functional processing shortly after trauma-exposure. We investigated brain activity patterns in response to trauma reminders as well as neutral and negative stimuli in individuals who had recently (within 3 weeks) been involved in a road traffic accident (RTA). Twenty-three RTA survivors and 17 non-trauma-exposed healthy controls (HCs) underwent functional MRI while viewing Trauma-specific, Negative, and Neutral pictures. Data were analyzed from four a priori regions of interest, including bilateral amygdala, subcallosal cortex, and medial prefrontal cortex. In addition, we performed a whole brain analysis and functional connectivity analysis during stimulus presentation. For both groups, Negative stimuli elicited more activity in the amygdala bilaterally than did Neutral and Trauma-specific stimuli. The whole brain analysis revealed higher activation in sensory processing related areas (bilateral occipital and temporal cortices and thalamus) as well as frontal and superior parietal areas, for the RTA group compared to HC, for Trauma-specific stimuli contrasted with Neutral stimuli. We also observed higher functional connectivity for Trauma-specific stimuli, between bilateral amygdala and somatosensory areas, for the RTA group compared to controls, when contrasted with Neutral stimuli. We argue that these results might indicate an attentional sensory processing bias toward Trauma-specific stimuli for trauma exposed individuals, a result in line with findings from the post-traumatic stress disorder literature.

  6. ASSESSING THE FUNCTIONAL ARCHITECTURE OF THE BRAIN WITH DIFFUSION MRI IN PAEDIATRIC PATIENTS

    OpenAIRE

    AMINOV KHABIBULLA

    2015-01-01

    The paper presents the results of the evaluation with MRI diffusion in the diagnosis of structural brain damage in children with symptomatic epilepsy in the background of developmental abnormalities of the brain and comparison of changes detected with routine MRI parameters. We studied parameters of MR diffusion weighted imaging in symptomatic epilepsy paediatric patients and determined the quantitative standards of numerical values of diffusion of white matter in children with symptomatic ep...

  7. Differential MRI Diagnosis Between Brain Abscess and Necrotic or Cystic Brain Tumors Using Diffusion Weighted Images

    Directory of Open Access Journals (Sweden)

    Zinat Miabi

    2009-01-01

    Full Text Available "nIntroduction: Differentiating brain abscesses from cystic or necrotic tumors by CT or MR imaging can be difficult. Difficulties in the diagnosis of intracranial abscess are mainly due to the combination of often unspecified clinical findings and similarities in the morphologic appearance of some intracranial mass lesions, such as cystic gliomas, metastases, and brain abscesses. Diffusion-weighted imaging provides a way to evaluate the diffusion properties of water molecules in tissue and has been used for diseases such as ischemia, tumors, epilepsy, and white matter disorders. The goal of this study was to evaluate the diagnostic utility of diffusion MRI to differentiate between brain abscesses and necrotic or cystic brain tumors. "nMaterials and Methods: MRI was performed in 17 patients (12 men and five women; age range, 19–74 years [mean, 55 years] with necrotic lesions and MR imaging evidence of ring-shaped enhancement after the injection of contrast material .In addition to standard MR sequences diffusion weighted MRI with apparent coefficient (ADC maps. "nResults: Eleven patients had tumors, and six had pyogenic abscesses. The tumors were glioblastomas (five patients, anaplastic astrocytoma (three patients, metastases (three patients, and primary malignancy, including lung (2 and breast (1 cancer. Surgical or stereotactic biopsies were obtained, and histologic studies were performed in all except one case (case 5. In the cases of abscess, bacteriologic analysis was also conducted. None of these lesions appeared hemorrhagic on T1-weighted images. "nConclusion: Diffusion-weighted imaging is useful for differentiating brain abscess from cystic or necrotic brain tumor, which is often difficult with conventional MR imaging. Diffusion-weighted imaging is useful as an additional imaging technique for establishing the differential diagnosis between brain abscesses and cystic or necrotic brain tumors. It requires less imaging time and is more

  8. 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

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

    International Nuclear Information System (INIS)

    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). 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. 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. 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. 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

  10. 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.

  11. 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. PMID:26481678

  12. 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.

  13. 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.

  14. 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. PMID:26791226

  15. 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. PMID:26827656

  16. Test-retest reliability of fMRI brain activity during memory-encoding

    Directory of Open Access Journals (Sweden)

    David J Brandt

    2013-12-01

    Full Text Available The mechanisms underlying hemispheric specialization of memory are not completely understood. Functional magnetic resonance imaging (fMRI can be used to develop and test models of hemispheric specialization. In particular for memory tasks however, the interpretation of fMRI results is often hampered by the low reliability of the data. In the present study we therefore analyzed the test-retest reliability of fMRI brain activation related to an implicit memory encoding task, with a particular focus on brain activity of the medial temporal lobe (MTL. Fifteen healthy subjects were scanned with fMRI on two sessions (average retest interval 35 days using a commonly applied novelty encoding paradigm contrasting known and unknown stimuli. To assess brain lateralization, we used three different stimuli classes that differed in their verbalizability (words, scenes, fractals. Test-retest reliability of fMRI brain activation was assessed by an intraclass-correlation coefficient (ICC, describing the stability of inter-individual differences in the brain activation magnitude over time. We found as expected a left-lateralized brain activation network for the words paradigm, a bilateral network for the scenes paradigm, and predominantly right-hemispheric brain activation for the fractals paradigm. Although these networks were consistently activated in both sessions on the group level, across-subject reliabilities were only poor to fair (ICCs ≤ 0.45. Overall, the highest ICC values were obtained for the scenes paradigm, but only in strongly activated brain regions. In particular the reliability of brain activity of the MTL was poor for all paradigms. In conclusion, for novelty encoding paradigms the interpretation of fMRI results on a single subject level is hampered by its low reliability. More studies are needed to optimize the retest reliability of fMRI activation for memory tasks.

  17. 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…

  18. Hypernatraemic dehydration in a neonate: brain MRI findings.

    Science.gov (United States)

    Musapasaoglu, H; Agildere, A Muhtesem; Teksam, M; Tarcan, A; Gurakan, B

    2008-02-01

    Severe hypernatremic dehydration can cause serious neurological complications in neonates. The most significant problems include brain oedema, intracranial haemorrhage, sinus thrombosis, haemorrhagic infarcts and permanent brain damage. The symptoms of many of these complications are similar. With respect to brain MRI findings in hypernatremic neonates, this is a report that describes linear lesions that represent intracranial haemorrhage at the grey-white matter junction. These MRI findings may be helpful for diagnosing hypernatremic dehydration, and for ruling out differential diagnoses for complications of this disorder.

  19. Functional connectivity analysis of the brain network using resting-state fMRI

    International Nuclear Information System (INIS)

    Spatial patterns of spontaneous fluctuations in blood oxygenation level-dependent (BOLD) signals reflect the underlying neural architecture. The study of the brain network based on these self-organized patterns is termed resting-state functional MRI (fMRI). This review article aims at briefly reviewing a basic concept of this technology and discussing its implications for neuropsychological studies. First, the technical aspects of resting-state fMRI, including signal sources, physiological artifacts, image acquisition, and analytical methods such as seed-based correlation analysis and independent component analysis, are explained, followed by a discussion on the major resting-state networks, including the default mode network. In addition, the structure-function correlation studied using diffuse tensor imaging and resting-state fMRI is briefly discussed. Second, I have discussed the reservations and potential pitfalls of 2 major imaging methods: voxel-based lesion-symptom mapping and task fMRI. Problems encountered with voxel-based lesion-symptom mapping can be overcome by using resting-state fMRI and evaluating undamaged brain networks in patients. Regarding task fMRI in patients, I have also emphasized the importance of evaluating the baseline brain activity because the amplitude of activation in BOLD fMRI is hard to interpret as the same baseline cannot be assumed for both patient and normal groups. (author)

  20. 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.

  1. 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.

  2. 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.

  3. Interaction vs. observation: distinctive modes of social cognition in human brain and behavior? A combined fMRI and eye-tracking study.

    Science.gov (United States)

    Tylén, Kristian; Allen, Micah; Hunter, Bjørk K; Roepstorff, Andreas

    2012-01-01

    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. PMID:23267322

  4. 99mTc-HMPAO Brain SPECT in Seizure Disorder: Comparison Brain SPECT, MRI / CT and EEG

    International Nuclear Information System (INIS)

    We studied 115 patients with seizure who had been performed brain SPECT brain MRI of CT and EEG. To evaluate the pattern of brain SPECT in seizure patients 28 of them had secondary epilepsies, 87 had primary epilepsies. In primary epilepsies, 42 were generalized seizure and 45 were partial seizure. The causes of secondary epilepsies were congenital malformation, cerebromalacia, cerebral infarction ultiple sclerosis, AV-malformation. granuloma and etc, in order. In 28 secondary epilepsies, 25 of them, brain SPECT lesions was concordant with MRI or CT lesions. 3 were disconcordant. The brain SPECT findings of generalized seizure were normal in 22 patients, diffuse irregular decreased perfusion in 8, decreased in frontal cortex in 4. temporal in 5 and frontotemporal in 3. In 45 partial seizure, 19 brain SPECT were concordant with EEG (42.4%).

  5. Repeated BOLD-fMRI imaging of deep brain stimulation responses in rats.

    Science.gov (United States)

    Chao, Tzu-Hao Harry; Chen, Jyh-Horng; Yen, Chen-Tung

    2014-01-01

    Functional magnetic resonance imaging (fMRI) provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol) with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP) thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1). The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91), and location (overlap ratio from 0.61 to 0.67). The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI. PMID:24825464

  6. Repeated BOLD-fMRI imaging of deep brain stimulation responses in rats.

    Directory of Open Access Journals (Sweden)

    Tzu-Hao Harry Chao

    Full Text Available Functional magnetic resonance imaging (fMRI provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1. The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91, and location (overlap ratio from 0.61 to 0.67. The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI.

  7. 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

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

    International Nuclear Information System (INIS)

    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

  9. Comparison of Hybrid Codes for MRI Brain Image Compression

    Directory of Open Access Journals (Sweden)

    G. Soundarya

    2012-12-01

    Full Text Available In general, medical images are compressed in a lossless manner in order to preserve details and to avoid wrong diagnosis. But this leads to a lower compression rate. Therefore, our aim is to improve the compression ratio by means of hybrid coding the MRI brain (tumor images. Hence we consider Region of Interest (ROI normally the abnormal region in the image and compress it without loss to achieve high compression ratio in par with maintaining high image quality and the Non-Region of Interest (Non-ROI of the image is compressed in a lossy manner. This study discusses two simple hybrid coding techniques (Hybrid A and Hybrid B on MRI human brain tumor image datasets. Also we evaluate their performance by comparing them with the standard lossless technique JPEG 2000 in terms of Compression Ratio (CR and Peak to Signal Noise Ratio (PSNR. Both hybrid codes have resulted in computationally economical scheme producing higher compression ratio than existing JPEG2000 and also meets the legal requirement of medical image archiving. The results obtained prove that our proposed hybrid schemes outperform existing schemes.

  10. 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).

  11. 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

  12. 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

  13. Synthetic MRI of the brain in a clinical setting

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    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.

  14. 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.

  15. 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.

  16. 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,…

  17. MRI evaluation and safety in the developing brain.

    Science.gov (United States)

    Tocchio, Shannon; Kline-Fath, Beth; Kanal, Emanuel; Schmithorst, Vincent J; Panigrahy, Ashok

    2015-03-01

    Magnetic resonance imaging (MRI) evaluation of the developing brain has dramatically increased over the last decade. Faster acquisitions and the development of advanced MRI sequences, such as magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI), perfusion imaging, functional MR imaging (fMRI), and susceptibility-weighted imaging (SWI), as well as the use of higher magnetic field strengths has made MRI an invaluable tool for detailed evaluation of the developing brain. This article will provide an overview of the use and challenges associated with 1.5-T and 3-T static magnetic fields for evaluation of the developing brain. This review will also summarize the advantages, clinical challenges, and safety concerns specifically related to MRI in the fetus and newborn, including the implications of increased magnetic field strength, logistics related to transporting and monitoring of neonates during scanning, and sedation considerations, and a discussion of current technologies such as MRI conditional neonatal incubators and dedicated small-foot print neonatal intensive care unit (NICU) scanners. PMID:25743582

  18. 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

  19. 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.)

  20. Imaging the premature brain: ultrasound or MRI?

    International Nuclear Information System (INIS)

    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.)

  1. Evaluation of the limits of visual detection of image misregistration in a brain fluorine-18 fluorodeoxyglucose PET-MRI study

    International Nuclear Information System (INIS)

    In routine clinical work, registration accuracy is assessed by visual inspection. However, the accuracy of visual assessment of registration has not been evaluated. This study establishes the limits of visual detection of misregistration in a registered brain fluorine-18 fluorodeoxyglucose positron emission tomography to magnetic resonance image volume. The ''best'' registered image volume was obtained by automatic registration using mutual information optimization. Translational movements by 1 mm, 2 mm, 3 mm and 4 mm, and rotational movements by 1 , 2 , 3 and 4 in the positive and negative directions in the x- (lateral), y- (anterior-posterior) and z- (axial) axes were introduced to this standard. These 48 images plus six ''best'' registered images were presented in random sequence to five observers for visual categorization of registration accuracy. No observer detected a definite misregistration in the ''best'' registered image. Evaluation for inter-observer variation using observer pairings showed a high percentage of agreement in assigned categories for both translational and rotational misregistrations. Assessment of the limits of detection of misregistration showed that a 2-mm translational misregistration was detectable by all observers in the x- and y-axes and 3-mm translational misregistration in the z-axis. With rotational misregistrations, rotation around the z-axis was detectable by all at 2 rotation whereas rotation around the y-axis was detected at 3-4 . Rotation around the x-axis was not symmetric with a positive rotation being identified at 2 whereas negative rotation was detected by all only at 4 . Therefore, visual analysis appears to be a sensitive and practical means to assess image misregistration accuracy. The awareness of the limits of visual detection of misregistration will lead to increase care when evaluating registration quality in both research and clinical settings. (orig.). With 6 figs., 3 tabs

  2. 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

  3. Brain MRI in Type 2 Diabetes

    OpenAIRE

    Tiehuis, A.M.

    2009-01-01

    In recent years is has become clear that type 2 diabetes affects the central nervous system. These long-term complications manifest as structural changes on brain imaging, cognitive decrements and a 1.5-2 fold increased risk for the development of dementia, in particular in the elderly. The pathogenesis of diabetes-induced brain damage is not completely understood. Both vascular and metabolic disturbances may play an important role in the impact of diabetes on the brain. The course of develop...

  4. Experience of brain checkup by MRI

    International Nuclear Information System (INIS)

    We performed head MRI and MR angiography (MRA) to find asymptomatic central nervous system (CNS) diseases and to prevent their development as a group health care. We performed 583 head MRI and MRAs since on March 1991 for the staff lived in Self Defence Force (SDF) Maizuru guard area whose age was 40 years, who reached the retirement age and had the risk factor of the cerebral vascular disease. We found 119 subcortical lesions, 26 asymptomatic cerebral infarctions, 6 unruptured cerebral aneurysm, 2 pituitary adenomas, 4 venous angiomas. For 5 cases of asymptomatic cerebral infarction, we prescribed anti-platelet agglutination drugs, there was no people whose disease became symptomatic. For unruptured cerebral aneurysms and pituitary adenomas, we did operation, everyone attained social rehabilitation. Before equipment of the MRI in SDF Maizuru hospital, 2 ruptured cerebral aneurysms occurs. There were no subarachnoid hemorrhage patient since our challenge started in SDF Maizuru guard area. It is useful to clarify the etiology of CNS disease and for group health care, using head MRI as medical checkup. (author)

  5. 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。

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.)

  11. 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.

  12. MRI of fetal acquired brain lesions

    International Nuclear Information System (INIS)

    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

  13. 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.)

  14. MRI brain findings in ephedrone encephalopathy associated with manganese abuse: Single-center perspective

    International Nuclear Information System (INIS)

    Manganese (Mn) is a well-known toxic agent causing symptoms of parkinsonism in employees of certain branches of industry. Home production of a psychostimulant ephedrone (methcathinone), involving the use of potassium permanganate, became a new cause of intoxications in Poland. This article presents clinical symptoms, initial brain MRI findings and characteristics of changes observed in follow-up examinations in 4 patients with manganese intoxication associated with intravenous administration of ephedrone. All patients in our case series presented symptoms of parkinsonism. T1-WI MRI revealed high intensity signal in globi pallidi in all patients; hyperintense lesions in midbrain were observed in three patients, while lesions located in cerebellar hemispheres and pituitary gland in just one patient. The reduction of signal intensity in the affected brain structures was observed in follow-up studies, with no significant improvement in clinical symptoms. Brain MRI is helpful in the assessment of distribution as well as dynamics of changes in ephedrone encephalopathy. Regression of signal intensity changes visible in brain MRI is not associated with clinical condition improvement. Although brain MRI findings are not characteristic for ephedrone encephalopathy, they may contribute to diagnosing this condition

  15. 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 AND...... METHODS: All the 28 Finnish patients participating in the Nordic multicentre trial on the clinical efficacy of weekly IFN-beta-1a (Rebif) 22 microg in SPMS were studied neurologically and by volumetric MRI during a 3-year follow-up. The levels of MMP-9 in serum were measured over the 3-year study. RESULTS......: There was no obvious effect on the number of contrast medium-enhancing lesions, the volume of T1 or T2 lesions or level of serum MMP-9, nor was any effect detected on the relapse rate and the Expanded Disability Status Scale (EDSS). Brain atrophy progression was not affected by the treatment. CONCLUSION...

  16. 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.

  17. Pre Operative Brain Mapping with Functional MRI in Patient with Brain Tumors: Preliminary Report

    Directory of Open Access Journals (Sweden)

    Sina Hooshmand

    2010-05-01

    Full Text Available Background/Objective: Functional Magnetic Resonance Imaging (fMRI plays a significant role in pre-neurosurgical planning at present. FMRI is a possible candidate to replace invasive methods for determination of the language dominant hemisphere and cortical areas associated with language and memory. We used this method to explore language and motor functions in healthy volunteers before creating standard paradigms for Persian language. In this study, we used the standard protocol of language and motor brain mapping in patients harboring brain tumors."nPatients and Methods: Ten patients with brain tumor were included in this study. Each subject performed three to five language related tasks during fMRI scan and also one motor related task. These tasks included; "Word Generation" (WG, "Object Naming" (ON, and "Word Reading" (WR, "Word Production" (WP and "Reverse Word Reading" (RWR. They also performed the thumb apposition task for activating primary sensory-motor areas. Fifteen continuous slices were acquired, and data analysis was carried out using FSL 4.1. After evaluating the individual results, the lateralization index (LI for each subject-task was calculated and the dominant hemisphere for language production was reported. Also localization of critical language areas in the cerebral cortex was performed and the coordinates of epicenter for language production in Broca's area was calculated."nResults: We found that WP, RWR, and WG activate language related areas in the dominant hemisphere robustly in patients with brain tumors and can predict the dominant hemisphere along with eloquent language cortices. However, ON and WR fail to delineate these activation areas optimally. In addition, the results reveal that higher activation intensities are obtained by WP in the frontal lobe including Broca's area, whereas RWR leads to the highest LI among all examined tasks. In patients harboring brain tumors, precise lateralization and

  18. 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.

  19. 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.

  20. 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

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

    International Nuclear Information System (INIS)

    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

  2. Local activity determines functional connectivity in the resting human brain: a simultaneous FDG-PET/fMRI study.

    Science.gov (United States)

    Riedl, Valentin; Bienkowska, Katarzyna; Strobel, Carola; Tahmasian, Masoud; Grimmer, Timo; Förster, Stefan; Friston, Karl J; Sorg, Christian; Drzezga, Alexander

    2014-04-30

    Over the last decade, synchronized resting-state fluctuations of blood oxygenation level-dependent (BOLD) signals between remote brain areas [so-called BOLD resting-state functional connectivity (rs-FC)] have gained enormous relevance in systems and clinical neuroscience. However, the neural underpinnings of rs-FC are still incompletely understood. Using simultaneous positron emission tomography/magnetic resonance imaging we here directly investigated the relationship between rs-FC and local neuronal activity in humans. Computational models suggest a mechanistic link between the dynamics of local neuronal activity and the functional coupling among distributed brain regions. Therefore, we hypothesized that the local activity (LA) of a region at rest determines its rs-FC. To test this hypothesis, we simultaneously measured both LA (glucose metabolism) and rs-FC (via synchronized BOLD fluctuations) during conditions of eyes closed or eyes open. During eyes open, LA increased in the visual system, and the salience network (i.e., cingulate and insular cortices) and the pattern of elevated LA coincided almost exactly with the spatial pattern of increased rs-FC. Specifically, the voxelwise regional profile of LA in these areas strongly correlated with the regional pattern of rs-FC among the same regions (e.g., LA in primary visual cortex accounts for ∼ 50%, and LA in anterior cingulate accounts for ∼ 20% of rs-FC with the visual system). These data provide the first direct evidence in humans that local neuronal activity determines BOLD FC at rest. Beyond its relevance for the neuronal basis of coherent BOLD signal fluctuations, our procedure may translate into clinical research particularly to investigate potentially aberrant links between local dynamics and remote functional coupling in patients with neuropsychiatric disorders. PMID:24790196

  3. 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)

  4. Brain CT and MRI findings of a long-term case of subacute sclerosing panencephalitis

    International Nuclear Information System (INIS)

    Our study involved a long-term case (ten years) of subacute sclerosing panencephalitis. The case began with a 23 year-old experiencing visual deterioration. During the course of his illness, amnesia, autism and abnormal behavior were observed without any myoclonus. On the electroencephalogram, periodic synclonous discharge was shown in the early stage of his illness and subsequently disappeared. The brain CT and the MRI disclosed diffuse lesions in both cortical and subcortical areas of the cerebral hemispheres. The location and spread of lesions were more clearly revealed by the MRI than the brain CT. These findings suggest that the MRI is more useful than the brain CT in the diagnosis of subacute sclerosing panencephalitis. (author)

  5. Brain CT and MRI findings of a long-term case of subacute sclerosing panencephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Aoshiba, Kazunori; Ota, Kohei; Komatsuzaki, Satoshi; Kobayashi, Itsuro; Maruyama, Shoichi

    1987-11-01

    Our study involved a long-term case (ten years) of subacute sclerosing panencephalitis. The case began with a 23 year-old experiencing visual deterioration. During the course of his illness, amnesia, autism and abnormal behavior were observed without any myoclonus. On the electroencephalogram, periodic synclonous discharge was shown in the early stage of his illness and subsequently disappeared. The brain CT and the MRI disclosed diffuse lesions in both cortical and subcortical areas of the cerebral hemispheres. The location and spread of lesions were more clearly revealed by the MRI than the brain CT. These findings suggest that the MRI is more useful than the brain CT in the diagnosis of subacute sclerosing panencephalitis.

  6. 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.

  7. 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.

  8. Functional MRI in human motor control studies and clinical applications

    International Nuclear Information System (INIS)

    Functional magnetic resonance imaging (fMRI) has been a useful tool for the noninvasive mapping of brain function associated with various motor and cognitive tasks. Because fMRI is based on the blood oxygenation level dependent (BOLD) effect, it does not directly record neural activity. With the fMRI technique, distinguishing BOLD signals creased by cortical projection neurons from those created by intracortical neurons appears to be difficult. Two major experimental designs are used in fMRI studies: block designs and event-related designs. Block-designed fMRI presupposes the steady state of regional cerebral blood flow and has been applied to examinations of brain activation caused by tasks requiring sustained or repetitive movements. By contrast, the more recently developed event-related fMRI with time resolution of a few seconds allows the mapping of brain activation associated with a single movement according to the transient aspects of the hemodynamic response. Increasing evidence suggests that multiple motor areas are engaged in a networked manner to execute various motor acts. In order to understand functional brain maps, it is important that one understands sequential and parallel organizations of anatomical connections between multiple motor areas. In fMRI studies of complex motor tasks, elementary parameters such as movement length, force, velocity, acceleration and frequency should be controlled, because inconsistency in those parameters may alter the extent and intensity of motor cortical activation, confounding interpretation of the findings obtained. In addition to initiation of movements, termination of movements plays an important role in the successful achievement of complex movements. Brain areas exclusively related to the termination of movements have been, for the first time, uncovered with an event-related fMRI technique. We propose the application of fMRI to the elucidation of the pathophysiology of movement disorders, particularly dystonia

  9. 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.

  10. 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

  11. Early studies of instant-fMRI for routine examination

    International Nuclear Information System (INIS)

    Authors are developing a low-burden, short-time acquisition method of functional magnetic resonance imaging (fMRI) with 3T machine, named ''Instant-fMRI'', aiming for its application to routine examinations, of which results of early studies on identification of the language hemisphere are reported. Subjects were 10 healthy volunteers (8 males, 2 females, mean age 34.2 y, 8 right-handers) and 5 right-hander patients with brain tumor (4 males, 1 female, mean age 50 y). The machine was GE Signa HDx 3.0T ver. 14, using 8 channel head coil. For Instant-fMRI, T1-weighted imaging sequence for mapping was in fast spoiled gradient recalled acquisition in the steady state (fSPGR) mode (scan time: 1 min 44 sec) and fMRI sequence, in GRE-EPI (scan time: 1 min), which thus required only about 3 min in total. Reference was defined to be the anterior-posterior commissure line, to which parallel sections involving centriciput and cerebellum were acquired. Rest (30 sec)-task (shiritori language game, 30 sec) cycle was to be one in instant-fMRI in contrast to three in the conventional fMRI. Volunteers received both instant-fMRI and conventional fMRI and patients, the former alone. Data were analyzed by GE Brain Wave PA. Right and left hemisphere of the left and right hander, respectively, was identified to be activated by instant-fMRI in 9 of 10 volunteers and in all patients, and by the conventional fMRI, in all volunteers. The instant-fMRI can be a useful examination of other brain functions as well as identifying the language field when acquisition parameters for desired diagnostic purpose are optimized. (T.T.)

  12. MRI findings of brain damage due to neonatal hypoglycemia

    International Nuclear Information System (INIS)

    Objective: To report the MRI findings of brain damage observed in neonatal patients who suffered from isolated hypoglycemia and to explore the value of diffusion-weighted imaging(DWI) in early detection of neonatal hypoglycemic brain injury. Methods: Twelve neonates with isolated hypoglycemia (10 of the 12 were diagnosed to suffer from hypoglycemic encephalopathy) were enrolled in this study. They were first scanned at age from 3 days to 10 days with T1WI, T2WI and DWI(b is 0 s/mm2, 1000 s/mm2), and 4 of them were then scanned from 7 days to 10 days following the initial scan. All acquired MR images were retrospectively analysed. Results: First series of DWI images showed distinct hyperintense signal in 11 cases in several areas including bilateral occipital cortex (2 cases), right occipital cortex (1 case), left occipital cortex and subcortical white matter(1 case), bilateral occipital cortex and subcortical white matter (2 cases), bilateral parieto-occipital cortex (2 cases), bilateral parieto-occipital cortex and subcortical white matter(2 cases), the splenium of corpus callosum (4 cases), bilateral corona radiata( 2 cases), left caudate nucleus and globus pallidus (1 case), bilateral thalamus (1 case), bilaterally posterior limb of internal capsule (1 case). In the initial T1WI and T2WI images, there were subtle hypointensity in the damaged cortical areas (3 cases), hyperintensity in the bilaterally affected occipital cortex( 1 case) on T1 weighted images, and hyperintensity in the affected cortex and subcortical white matter with poor differentiation on T2 weighted images. The followed-up MRI of 4 cases showed regional encephalomalacia in the affected occipital lobes(4 cases), slightly hyperintensity on T2 weighted images in the damaged occipital cortex (2 cases), extensive demyelination (1 case), disappearance of hyperintensity of the splenium of corpus callosum (1 case), and persistent hyperintensity in the splenium of corpus callosum (1 case) on T2 weighted

  13. 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.

  14. The highly sensitive brain: an fMRI study of sensory processing sensitivity and response to others' emotions

    OpenAIRE

    Acevedo, Bianca P.; Aron, Elaine N.; Aron, Arthur; Sangster, Matthew-Donald; Collins, Nancy; Brown, Lucy L.

    2014-01-01

    Background Theory and research suggest that sensory processing sensitivity (SPS), found in roughly 20% of humans and over 100 other species, is a trait associated with greater sensitivity and responsiveness to the environment and to social stimuli. Self-report studies have shown that high-SPS individuals are strongly affected by others' moods, but no previous study has examined neural systems engaged in response to others' emotions. Methods This study examined the neural correlates of SPS (me...

  15. Morphological asymmetries of mouse brain assessed by geometric morphometric analysis of MRI data.

    Science.gov (United States)

    Barbeito-Andrés, Jimena; Bernal, Valeria; Gonzalez, Paula N

    2016-09-01

    Mammalian brain has repeated structures at both sides of the median plane, although some asymmetries have been described even under normal conditions. Characterizing normal patterns of asymmetry in mouse brain is important to recognize features that depart from expected ranges in the most widely used mammalian model. Analyses on brain morphology based on magnetic resonance image (MRI) have largely focused on volumes while less is known about shape asymmetry. We introduce a flexible protocol based on geometric morphometrics to assess patterns of asymmetry in shape and size of mouse brain from microMRI scans. After systematic digitization of landmarks and semilandmarks, we combine multivariate methods for statistical analyses with visualization tools to display the results. No preliminary treatment of the images (e.g. space normalization) is needed to collect data on MRI slices and visual representations improve the interpretation of the results. Results indicated that the protocol is highly repeatable. Asymmetry was more evident for shape than for size. Particularly, fluctuating asymmetry accounted for more variation than directional asymmetry in all brain regions. Since this approach can detect subtle shape variation between sides, it is a promising methodology to explore morphological changes in the brain of model organisms and can be applied in future studies addressing the effect of genetic and environmental factors on brain morphology. PMID:27108357

  16. Brain MRI Anatomical and Attention and Behavior Disorders With 22qll.2 Deletion Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-05-01

    Full Text Available The brain anatomy of 39 children and adolescents with 22qDS (mean age 11 years; IQ 67 and 26 sibling controls (mean age 11 years; IQ 102 was compared using MRI and automated voxel-based morphometry, and behavioral differences were correlated with affected brain regions in a study at King’s College, Institute of Psychiatry, London, UK; Royal College of Surgeons, Dublin, Ireland; and Academic Medical Center, Amsterdam, Holland.

  17. Clinical evaluation of 3D/3D MRI-CBCT automatching on brain tumors for online patient setup verification - A step towards MRI-based treatment planning

    DEFF Research Database (Denmark)

    Buhl, Sune K.; Duun-Christensen, Anne Katrine; Kristensen, Brian H.;

    2010-01-01

    Background. Magnetic Resonance Imaging (MRI) is often used in modern day radiotherapy (RT) due to superior soft tissue contrast. However, treatment planning based solely on MRI is restricted due to e. g. the limitations of conducting online patient setup verification using MRI as reference....... In this study 3D/3D MRI-Cone Beam CT (CBCT) automatching for online patient setup verification was investigated. Material and methods. Initially, a multi-modality phantom was constructed and used for a quantitative comparison of CT-CBCT and MRI-CBCT automatching. Following the phantom experiment three patients...... undergoing postoperative radiotherapy for malignant brain tumors received a weekly CBCT. In total 18 scans was matched with both CT and MRI as reference. The CBCT scans were acquired using a Clinac iX 2300 linear accelerator (Varian Medical Systems) with an On-Board Imager (OBI). Results. For the phantom...

  18. Clinical evaluation of 3D/3D MRI-CBCT automatching on brain tumors for online patient setup verification - A step towards MRI-based treatment planning

    DEFF Research Database (Denmark)

    Buhl, S.K.; Duun-Christensen, Anne Katrine; Kristensen, B.H.;

    2010-01-01

    undergoing postoperative radiotherapy for malignant brain tumors received a weekly CBCT. In total 18 scans was matched with both CT and MRI as reference. The CBCT scans were acquired using a Clinac iX 2300 linear accelerator (Varian Medical Systems) with an On-Board Imager (OBI). Results. For the phantom......Background. Magnetic Resonance Imaging (MRI) is often used in modern day radiotherapy (RT) due to superior soft tissue contrast. However, treatment planning based solely on MRI is restricted due to e. g. the limitations of conducting online patient setup verification using MRI as reference....... In this study 3D/3D MRI-Cone Beam CT (CBCT) automatching for online patient setup verification was investigated. Material and methods. Initially, a multi-modality phantom was constructed and used for a quantitative comparison of CT-CBCT and MRI-CBCT automatching. Following the phantom experiment three patients...

  19. Emotional valence modulates brain functional abnormalities in depression : Evidence from a meta-analysis of fMRI studies

    NARCIS (Netherlands)

    Groenewold, Nynke A.; Opmeer, Esther M.; de Jonge, Peter; Aleman, Andre; Costafreda, Sergi G.

    2013-01-01

    Models describing the neural correlates of biased emotion processing in depression have focused on increased activation of anterior cingulate and amygdala and decreased activation of striatum and dorsolateral prefrontal cortex. However, neuroimaging studies investigating emotion processing in depres

  20. Cognitive functioning and brain MRI in patients with type 1 and type 2 diabetes mellitus : A comparative study

    NARCIS (Netherlands)

    Brands, Augustina M. A.; Biessels, Geert Jan; Kappelle, L. Jaap; de Haan, Edward H. F.; de Valk, Harold W.; Algra, Ale; Kessels, Roy P. C.

    2007-01-01

    Background/Aims: Diabetes mellitus (DM) may affect the central nervous system, resulting in cognitive impairments. It has been suggested that cognitive impairments are more pronounced in DM2 than in DM1, but studies that directly compare the effects of these 2 types of DM on cognition are lacking. M

  1. 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

  2. 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 Emil Borch Laurs; 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...

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

    OpenAIRE

    Liu, Hua; Song, Luping; Zhang, Tong

    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 practic...

  4. The brain MRI classification problem from wavelets perspective

    Science.gov (United States)

    Bendib, Mohamed M.; Merouani, Hayet F.; Diaba, Fatma

    2015-02-01

    Haar and Daubechies 4 (DB4) are the most used wavelets for brain MRI (Magnetic Resonance Imaging) classification. The former is simple and fast to compute while the latter is more complex and offers a better resolution. This paper explores the potential of both of them in performing Normal versus Pathological discrimination on the one hand, and Multiclassification on the other hand. The Whole Brain Atlas is used as a validation database, and the Random Forest (RF) algorithm is employed as a learning approach. The achieved results are discussed and statistically compared.

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

    International Nuclear Information System (INIS)

    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.

  6. 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.

  7. 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.

  8. An exploratory intervention study suggests clinical benefits of training in chronic stroke to be paralleled by changes in brain activity using repeated fMRI

    Directory of Open Access Journals (Sweden)

    Landsmann B

    2016-01-01

    Full Text Available Barbara Landsmann,1,2 Daniela Pinter,2 Eva Pirker,1,2 Gerald Pichler,3 Walter Schippinger,3 Elisabeth M Weiss,1 Gabriel Mathie,2 Thomas Gattringer,2 Franz Fazekas,2 Christian Enzinger2,4 1Institute of Psychology, University of Graz, Graz, Austria; 2Department of Neurology, Medical University of Graz, Graz, Austria; 3Albert Schweitzer Clinic Graz, Graz, Austria; 4Division of Neuroradiology, Department of Radiology, Medical University of Graz, Graz, Austria Purpose: Previous studies demonstrated changes in sensorimotor network activation over time after stroke that have been interpreted as partly compensatory. Locomotor and balance trainings may improve both mobility and cognition even in chronic stroke and thereby impact on cerebral activation patterns. We here aimed at testing these assumptions in an exploratory study to inform subsequent larger intervention studies. Patients and methods: Eight patients (73.3±4.4 years with a chronic lacunar stroke (mean interval 3.7 years after the acute event with a range from 2 to 4 years and residual leg paresis leading to gait disturbance received a guided 5-week training focusing on mobility, endurance, and coordination. Before and afterward, they underwent clinical, neuropsychological, and gait assessments and brain MRI at 3 T including a functional ankle movement paradigm. Sixteen healthy controls (HCs; 68.8±5.4 years followed the same protocol without intervention. Results: After training, patients had improved in mobility, memory, and delayed recall of memory. While cerebral activations in HC remained completely unaltered, patients showed increased activations in the right precentral gyrus, the right and left superior frontal gyri, and the right frontal lobe, with bipedal ankle movements after training. Conclusion: In this exploratory study of chronic stroke, we found not only significant effects of physical training on mobility but also distinct aspects of cognition already with a small number of

  9. 脑脉络膜裂MRI解剖研究及脉络膜裂囊肿影像分析%MRI anatomic study of choroidal fissure and imaging analysis of choroidal fissure cyst of brain

    Institute of Scientific and Technical Information of China (English)

    邹子仪; 高振华; 胡晓书

    2011-01-01

    Objective To study MRI anatomic characteristics of choroidal fissure of brain in vivo and the clinical significance and CT and MRI findings of choroidal fissure cyst.Methods MR images of choroidal fissures in 90 normal brains aged between 20 and 50 were retrospectively analyzed, combining with the anatomical observation of one cadaveric head.At the same time, MRI findings of 20 patients with choroidal fissure cyst in brain were observed.Results Gross dissection showed C- shaped choroid fissure of brain accompanied with lateral ventricle.Choroid fissures could be clearly shown on MRI, demonstrating the linear fissure full of cerebrospinal fluid and nearly the same width in adult before 50 years old.Choroid fissure cyst was displayed as round or oval foci of cerebrospinal fluid- like density or signal intensity in choroid fissure on CT or MR imaging.Conclusion The understanding of the anatomical characteristics of brain choroid fissure and normal MRI findings may be very significant for the diagnosis of choroidal fissure cyst.%目的 探讨脑脉络膜裂的MRI解剖学特点及脉络膜裂囊肿的CT和MRI表现.方法 结合1例颅脑标本的解剖观察,分析90例20~50岁正常脑脉络膜裂的MRI表现并测量其宽度,同时分析20例脑脉络膜裂囊肿的CT和MRI表现.结果 经颅脑标本解剖观察脑脉络膜裂呈"C"形裂隙,深处由室管膜封闭,侧脑室内的脉络丛附着于此裂隙并与之走行一致.脉络膜裂在MRI上为含脑脊液的线状裂隙,50岁前成人裂隙的宽度相差不大.脑脉络膜裂囊肿CT和MRI表现为脑脉络膜裂内类圆形或椭圆形的脑脊液密度或信号.结论 了解脑脉络膜裂的解剖学特征及其正常MRI表现,对于脉络膜裂囊肿诊断具有重要意义.

  10. volBrain: An Online MRI Brain Volumetry System.

    Science.gov (United States)

    Manjón, José V; Coupé, Pierrick

    2016-01-01

    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. PMID:27512372

  11. volBrain: An Online MRI Brain Volumetry System

    Science.gov (United States)

    Manjón, José V.; Coupé, Pierrick

    2016-01-01

    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.

  12. 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.

  13. 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.)

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

    Science.gov (United States)

    Pannek, Kerstin; Guzzetta, Andrea; Colditz, Paul B; Rose, Stephen E

    2012-10-01

    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. PMID:22903761

  15. MRI findings of radiation encephalopathy of brain stem after radiotherapy for nasopharyngeal cancer

    International Nuclear Information System (INIS)

    Purpose: To study MRI findings and clinical manifestation of radiation encephalopathy (RE) of brain stem. Methods: MRI findings and clinical symptoms in 51 patients with RE of brain stem after radiotherapy for nasopharyngeal cancer were reviewed. Results: Clinical symptoms included number weakness or paralysis in the limbs and symptoms of damaged cranial nerves. All lesions appeared hypo- or iso-intense on spin echo(SE) T1-weighted images and inhomogeneous and mixed hyper- and iso-intense on Turbo spin echo (TSE) T2-weighted images. The lesions were located in mesencephalon, pons, medulla, basilar part of pons, basilar part of pons and medulla oblongata in 2,7,3,9 and 30 patients respectively. The enhancement patterns included irregular rings in 39 patients, spotty in 3 and no enhancement in 9 patients. Mass effect was minimal in all patients. On follow-up MRI, the lesions disappeared in 4 patients, did not change in size and shape in 8 patients and enlarged in 2 patients. Conclusion: MRI could demonstrate the characteristic findings of RE of brain stem. MRI findings sometimes are not consistent with the clinical symptoms

  16. MRI quantitative assessment of brain maturation and prognosis in premature infants using total maturation score

    International Nuclear Information System (INIS)

    Objective: To quantitatively assess brain maturation and prognosis in premature infants on conventional MRI using total maturation score (TMS). Methods: Nineteen cases of sequelae of white matter damage (WMD group )and 21 cases of matched controls (control group) in premature infants confirmed by MRI examinations were included in the study. All cases underwent conventional MR imaging approximately during the perinatal period after birth. Brain development was quantitatively assessed using Childs AM's validated scoring system of TMS by two sophisticated radiology physicians. Interobserver agreement and reliability was evaluated by using intraclass correlation (ICC). Linear regression analysis between TMS and postmenstrual age (PMA) was made(Y: TMS, X: PMA). Independent-sample t test of the two groups' TMS was made. Results: Sixteen of 19 cases revealed MRI abnormalities. Lesions showing T1 and T2 shortening tended to occur in clusters or a linear pattern in the deep white matter of the centrum semiovale, periventricular white matter. Diffusion-weighted MR image (DWI) showed 3 cases with greater lesions and 4 cases with new lesions in corpus callosum. There was no abnormality in control group on MRI and DWI. The average numbers of TMS between the two observers were 7.13±2.27, 7.13±2.21. Interobservcer agreement was found to be high (ICC=0.990, P2=0.6401,0.5156 respectively, P0.05). Conclusion: Conventional MRI is able to quantify the brain maturation and prognosis of premature infants using TMS. (authors)

  17. Longitudinal brain MRI analysis with uncertain registration.

    Science.gov (United States)

    Simpson, Ivor J A; Woolrich, Mark W; Groves, Adrian R; Schnabel, Julia A

    2011-01-01

    In this paper we propose a novel approach for incorporating measures of spatial uncertainty, which are derived from non-rigid registration, into spatially normalised statistics. Current approaches to spatially normalised statistical analysis use point-estimates of the registration parameters. This is limiting as the registration will rarely be completely accurate, and therefore data smoothing is often used to compensate for the uncertainty of the mapping. We derive localised measurements of spatial uncertainty from a probabilistic registration framework, which provides a principled approach to image smoothing. We evaluate our method using longitudinal deformation features from a set of MR brain images acquired from the Alzheimer's Disease Neuroimaging Initiative. These images are spatially normalised using our probabilistic registration algorithm. The spatially normalised longitudinal features are adaptively smoothed according to the registration uncertainty. The proposed adaptive smoothing shows improved classification results, (84% correct Alzheimer's Disease vs. controls), over either not smoothing (79.6%), or using a Gaussian filter with sigma = 2mm (78.8%). PMID:21995084

  18. 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.

  19. 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).

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

    International Nuclear Information System (INIS)

    Single photon emission computed tomography (SPECT) using N-isopropyl-p-[123I]-iodoamphetamine (123I-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)

  1. Development and Application of Tools for MRI Analysis - A Study on the Effects of Exercise in Patients with Alzheimer's Disease and Generative Models for Bias Field Correction in MR Brain Imaging

    DEFF Research Database (Denmark)

    Larsen, Christian Thode

    Magnetic resonance imaging (MRI) is the de facto modality in neuroimaging studies, due to its superior image contrast in soft tissue. These studies often employ automated software pipelines that segments the image into structures and tissue. This reduces the time needed for analysis as well...... in several cognitive performance measures, including mental speed, attention and verbal uency. MRI suffers from an image artifact often referred to as the "bias field”. This effect complicates automatized analysis of the images. For this reason, bias field correction is typical an early preprocessing step...... for longitudinal correction of the bias field, as well as a model that does not require brain masking or probabilistic, anatomical atlases in order to perform well. Finally, the thesis presents the realization of these models in the software package "Intensity Inhomogeneity Correction”, which will be made publicly...

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

    International Nuclear Information System (INIS)

    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.)

  3. 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.).

  4. 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.)

  5. 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.

  6. Statistical shape model-based segmentation of brain MRI images.

    Science.gov (United States)

    Bailleul, Jonathan; Ruan, Su; Constans, Jean-Marc

    2007-01-01

    We propose a segmentation method that automatically delineates structures contours from 3D brain MRI images using a statistical shape model. We automatically build this 3D Point Distribution Model (PDM) in applying a Minimum Description Length (MDL) annotation to a training set of shapes, obtained by registration of a 3D anatomical atlas over a set of patients brain MRIs. Delineation of any structure from a new MRI image is first initialized by such registration. Then, delineation is achieved in iterating two consecutive steps until the 3D contour reaches idempotence. The first step consists in applying an intensity model to the latest shape position so as to formulate a closer guess: our model requires far less priors than standard model in aiming at direct interpretation rather than compliance to learned contexts. The second step consists in enforcing shape constraints onto previous guess so as to remove all bias induced by artifacts or low contrast on current MRI. For this, we infer the closest shape instance from the PDM shape space using a new estimation method which accuracy is significantly improved by a huge increase in the model resolution and by a depth-search in the parameter space. The delineation results we obtained are very encouraging and show the interest of the proposed framework. PMID:18003193

  7. 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.

  8. 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.

  9. 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.

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

    International Nuclear Information System (INIS)

    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 T1-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 T1-weighted MRI sequences and without deformable registrations. In our evaluations, the method performed better than existing voxel-based and atlas

  11. 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

  12. 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.)

  13. Brain 18F-FDG PET-MRI co registration: iconographic essay

    International Nuclear Information System (INIS)

    The combination of positron emission tomography (PET) with magnetic resonance imaging (MRI) has been the subject of several studies in recent years. Positron emission tomography is the most sensitive and specific imaging modality in the detection of metabolic changes, but presents limited spatial resolution. On the other hand, MRI presents a significant spatial resolution, besides evaluating soft tissues signal intensity with excellent contrast resolution. The present iconographic essay is aimed at demonstrating the potential clinical application of PET/MRI co registration. The studies were performed in a dedicated PET unit with 18F-fluorodeoxyglucose (FDG) as radiopharmaceutical and co registered with 1.5 T or 3 T brain MRI. The brain images fusion software presents an already well-established accuracy, so a significant synergy between a functional PET study and an excellent MRI anatomical detail is achieved. The most attractive clinical applications of this approach are the following: epileptogenic zone assessment in patients refractory to drug therapy, identification of patients with cognitive impairment at higher risk for progression to dementia and differentiation of dementias and Parkinsonian syndromes. (author)

  14. An fMRI Study on Right Brain Activity Characteristics for Chinese Phonological Processing in Literate Subjects%汉字读音判断时非文盲右脑活动特征的fMRI研究

    Institute of Scientific and Technical Information of China (English)

    李修军; 李奇; 郭启勇; 吴景龙

    2013-01-01

    Using functional magnetic resonance imaging (fMRI),much knowledge has been gained in understanding how the brain is activated during controlling experiments of language tasks in educated healthy subjects and in uneducated healthy subjects. While previous studies have compared performance between alphabetic subjects, few data were about Chinese-speaking individuals. In this study, fMRI was used to investigate brain activations in processing characters and pure tone in 26 Chinese subjects (13 illiterates and 13 literates) .Different activation patterns were observed in not only Chinese character voice judgment task, but also pure tone judgment task between literates and illiterates. The result show that constellation of neural substrates was different for literates and illiterates;educatee may enhance this brain plasticity.%利用功能性磁共振成像(fMRI)技术探讨汉字语音判断时非文盲的大脑活动特征。实验使用汉字语音和纯音比较了中国人文盲和非文盲语音加工过程脑机制的差异。结果表明文盲与非文盲汉字语音加工脑机制不同,且非文盲的脑活动强,尤其是右脑。

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

    International Nuclear Information System (INIS)

    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.)

  16. 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.

  17. 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.)

  18. MRI-guided brain PET image filtering and partial volume correction.

    Science.gov (United States)

    Yan, Jianhua; Lim, Jason Chu-Shern; Townsend, David W

    2015-02-01

    Positron emission tomography (PET) image quantification is a challenging problem due to limited spatial resolution of acquired data and the resulting partial volume effects (PVE), which depend on the size of the structure studied in relation to the spatial resolution and which may lead to over or underestimation of the true tissue tracer concentration. In addition, it is usually necessary to perform image smoothing either during image reconstruction or afterwards to achieve a reasonable signal-to-noise ratio. Typically, an isotropic Gaussian filtering (GF) is used for this purpose. However, the noise suppression is at the cost of deteriorating spatial resolution. As hybrid imaging devices such as PET/MRI have become available, the complementary information derived from high definition morphologic images could be used to improve the quality of PET images. In this study, first of all, we propose an MRI-guided PET filtering method by adapting a recently proposed local linear model and then incorporate PVE into the model to get a new partial volume correction (PVC) method without parcellation of MRI. In addition, both the new filtering and PVC are voxel-wise non-iterative methods. The performance of the proposed methods were investigated with simulated dynamic FDG brain dataset and (18)F-FDG brain data of a cervical cancer patient acquired with a simultaneous hybrid PET/MR scanner. The initial simulation results demonstrated that MRI-guided PET image filtering can produce less noisy images than traditional GF and bias and coefficient of variation can be further reduced by MRI-guided PET PVC. Moreover, structures can be much better delineated in MRI-guided PET PVC for real brain data. PMID:25575248

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

    International Nuclear Information System (INIS)

    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. Tracking of magnetite labeled nanoparticles in the rat brain using MRI.

    Directory of Open Access Journals (Sweden)

    Naira P Martínez Vera

    Full Text Available This study was performed to explore the feasibility of tracing nanoparticles for drug transport in the healthy rat brain with a clinical MRI scanner. Phantom studies were performed to assess the R1 ( =  1/T1 relaxivity of different magnetically labeled nanoparticle (MLNP formulations that were based on biodegradable human serum albumin and that were labeled with magnetite of different size. In vivo MRI measurements in 26 rats were done at 3T to study the effect and dynamics of MLNP uptake in the rat brain and body. In the brain, MLNPs induced T1 changes were quantitatively assessed by T1 relaxation time mapping in vivo and compared to post-mortem results from fluorescence imaging. Following intravenous injection of MLNPs, a visible MLNP uptake was seen in the liver and spleen while no visual effect was seen in the brain. However a histogram analysis of T1 changes in the brain demonstrated global and diffuse presence of MLNPs. The magnitude of these T1 changes scaled with post-mortem fluorescence intensity. This study demonstrates the feasibility of tracking even small amounts of magnetite labeled NPs with a sensitive histogram technique in the brain of a living rodent.

  1. 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.

  2. 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.

  3. 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

  4. Technological advances in MRI measurement of brain perfusion.

    Science.gov (United States)

    Duyn, Jeff H; van Gelderen, Peter; Talagala, Lalith; Koretsky, Alan; de Zwart, Jacco A

    2005-12-01

    Measurement of brain perfusion using arterial spin labeling (ASL) or dynamic susceptibility contrast (DSC) based MRI has many potential important clinical applications. However, the clinical application of perfusion MRI has been limited by a number of factors, including a relatively poor spatial resolution, limited volume coverage, and low signal-to-noise ratio (SNR). It is difficult to improve any of these aspects because both ASL and DSC methods require rapid image acquisition. In this report, recent methodological developments are discussed that alleviate some of these limitations and make perfusion MRI more suitable for clinical application. In particular, the availability of high magnetic field strength systems, increased gradient performance, the use of RF coil arrays and parallel imaging, and increasing pulse sequence efficiency allow for increased image acquisition speed and improved SNR. The use of parallel imaging facilitates the trade-off of SNR for increases in spatial resolution. As a demonstration, we obtained DSC and ASL perfusion images at 3.0 T and 7.0 T with multichannel RF coils and parallel imaging, which allowed us to obtain high-quality images with in-plane voxel sizes of 1.5 x 1.5 mm(2). PMID:16267852

  5. Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs

    OpenAIRE

    Klemen Jane; Vollstädt-Klein Sabine; Bühler Mira; Smolka Michael N

    2008-01-01

    Abstract Background Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. Methods To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. Results Brain activation differed...

  6. Brain region and activity-dependent properties of M for calibrated fMRI.

    Science.gov (United States)

    Shu, Christina Y; Herman, Peter; Coman, Daniel; Sanganahalli, Basavaraju G; Wang, Helen; Juchem, Christoph; Rothman, Douglas L; de Graaf, Robin A; Hyder, Fahmeed

    2016-01-15

    Calibrated fMRI extracts changes in oxidative energy demanded by neural activity based on hemodynamic and metabolic dependencies of the blood oxygenation level-dependent (BOLD) response. This procedure requires the parameter M, which is determined from the dynamic range of the BOLD signal between deoxyhemoglobin (paramagnetic) and oxyhemoglobin (diamagnetic). Since it is unclear if the range of M-values in human calibrated fMRI is due to regional/state differences, we conducted a 9.4T study to measure M-values across brain regions in deep (α-chloralose) and light (medetomidine) anesthetized rats, as verified by electrophysiology. Because BOLD signal is captured differentially by gradient-echo (R2*) and spin-echo (R2) relaxation rates, we measured M-values by the product of the fMRI echo time and R2' (i.e., the reversible magnetic susceptibility component), which is given by the absolute difference between R2* and R2. While R2' mapping was shown to be dependent on the k-space sampling method used, at nominal spatial resolutions achieved at high magnetic field of 9.4T the M-values were quite homogenous across cortical gray matter. However cortical M-values varied in relation to neural activity between brain states. The findings from this study could improve precision of future calibrated fMRI studies by focusing on the global uniformity of M-values in gray matter across different resting activity levels. PMID:26529646

  7. 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.)

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

    International Nuclear Information System (INIS)

    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.)

  9. INFARCT DETECTION IN BRAIN MRI USING IMPROVED SEGMENTATION ALGORITHM AND VOLUME VISUALIZATION

    OpenAIRE

    Praveen Kumar E; Sumithra M G; Sunil Kumar P

    2013-01-01

    In the present days, for the human body anatomical study and for the treatment planning medicalscience very much depend on the medical imaging technology and medical images. Specifically for thehuman brain, MRI widely prefers and using for the imaging. But by nature medical images are complex andnoisy.This leads to the necessity of processes that reduces difficulties in analysis and improves quality ofoutput.This paper discuss about an improved segmentation algorithm for infarct detection in ...

  10. Segmentation of Tumor Region in MRI Images of Brain using Mathematical Morphology

    OpenAIRE

    Ashwini Gade; Rekha Vig; Vaishali Kulkarni

    2014-01-01

    This paper introduces an efficient detection of brain tumor from cerebral MRI images. The methodology consists of two steps: enhancement and segmentation. To improve the quality of images and limit the risk of distinct regions fusion in the segmentation phase an enhancement process is applied. We applied mathematical morphology to increase the contrast in MRI images and to segment MRI images. Some of experimental results on brain images show the feasibility and the performance of the proposed...

  11. Segmentation of Tumor Region in MRI Images of Brain using Mathematical Morphology

    Directory of Open Access Journals (Sweden)

    Ashwini Gade

    2014-06-01

    Full Text Available This paper introduces an efficient detection of brain tumor from cerebral MRI images. The methodology consists of two steps: enhancement and segmentation. To improve the quality of images and limit the risk of distinct regions fusion in the segmentation phase an enhancement process is applied. We applied mathematical morphology to increase the contrast in MRI images and to segment MRI images. Some of experimental results on brain images show the feasibility and the performance of the proposed approach.

  12. 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.)

  13. 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.

  14. 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.

  15. Evaluation of image quality of MRI data for brain tumor surgery

    Science.gov (United States)

    Heckel, Frank; Arlt, Felix; Geisler, Benjamin; Zidowitz, Stephan; Neumuth, Thomas

    2016-03-01

    3D medical images are important components of modern medicine. Their usefulness for the physician depends on their quality, though. Only high-quality images allow accurate and reproducible diagnosis and appropriate support during treatment. We have analyzed 202 MRI images for brain tumor surgery in a retrospective study. Both an experienced neurosurgeon and an experienced neuroradiologist rated each available image with respect to its role in the clinical workflow, its suitability for this specific role, various image quality characteristics, and imaging artifacts. Our results show that MRI data acquired for brain tumor surgery does not always fulfill the required quality standards and that there is a significant disagreement between the surgeon and the radiologist, with the surgeon being more critical. Noise, resolution, as well as the coverage of anatomical structures were the most important criteria for the surgeon, while the radiologist was mainly disturbed by motion artifacts.

  16. 实验性癫癎大鼠脑MRI与病理学对照研究%Comparative Study of MRI and Pathology of Epilepsy Caused Brain Injury in Rat

    Institute of Scientific and Technical Information of China (English)

    叶静; 张文波; 祁吉; 韩悦; 廉宗澄

    2000-01-01

    目的:观察1.5TMRI检出大鼠性脑损伤的能力。材料和方法:Wistar大鼠30只,毛果云香碱350mg/kg腹腔注射,诱发反复强直-痉挛全面大发作持续状态,HE染色,光镜下观察癫癎持续不同时间脑组织损害程度,并与1.5TMR成像对比(MRI参数:SE序列T1加权像:重复时间=500ms,回波时间=15ms;FSE序列T2加权像:重复时间=400ms,回波时间=100ms;用表面线圈,层厚2.2mm,无间隔)。结果:癫癎持续时间与脑损伤呈相关性改变。癫癎持续3h后,可见颞叶、海马区严重神经元脱失、胶质增生和脑水肿;MR扫描除在1只发作持续18h的大鼠左颞区检出长T1、长T2异常信号外(光镜提示为出血灶),未发现其余动物脑的结构异常和信号变化。结论:随着动物大发作持续时间延长,性脑损害加重,大鼠癫癎持续3h以上,有明显的海马神经元坏死及胶质增生,形成典型的海马硬化;1.5TMR常规序列扫描尚不能检出癫癎大鼠早期脑改变。%Purpose: To observe the ability of demonstration of epilepsy caused brain injury with MRI in epileptogenic rats. Materials and Methods: Thirty Wistar rats were injected with 10% pilocarpine intraperitoneally to induce a generalized tonic - clonic seizure(GTCS) . The degrees of brain injury with different duration of epilepsy were observed with light microscope and compared with 1.5 T MRI findings(SE: T1 WI, FSE: T2 WI, Coil: surface coil, Thickness: 2.2mm without gap). Results: The duration of GTCS and the degree of brain injury in pathological study correlated fairly. After3 hours continuous GTCS, severe neuronal loss, gliosis and edema in the temporal lobe and hippocampal region were found by pathology, and no abnormlity was revealed with MRI, MRI showed low signal intensity on T1 WI and high signal intensity on T2WI images in the left temporal lobe in one rat with GTCS lasting 18 hours. These abnormal signals were from hemorrhage

  17. Change in brain network topology as a function of treatment response in schizophrenia: a longitudinal resting-state fMRI study using graph theory.

    Science.gov (United States)

    Hadley, Jennifer Ann; Kraguljac, Nina Vanessa; White, David Matthew; Ver Hoef, Lawrence; Tabora, Janell; Lahti, Adrienne Carol

    2016-01-01

    A number of neuroimaging studies have provided evidence in support of the hypothesis that faulty interactions between spatially disparate brain regions underlie the pathophysiology of schizophrenia, but it remains unclear to what degree antipsychotic medications affect these. We hypothesized that the balance between functional integration and segregation of brain networks is impaired in unmedicated patients with schizophrenia, but that it can be partially restored by antipsychotic medications. We included 32 unmedicated patients with schizophrenia (SZ) and 32 matched healthy controls (HC) in this study. We obtained resting-state scans while unmedicated, and again after 6 weeks of treatment with risperidone to assess functional integration and functional segregation of brain networks using graph theoretical measures. Compared with HC, unmedicated SZ showed reduced global efficiency and increased clustering coefficients. This pattern of aberrant functional network integration and segregation was modulated with antipsychotic medications, but only in those who responded to treatment. Our work lends support to the concept of schizophrenia as a dysconnectivity syndrome, and suggests that faulty brain network topology in schizophrenia is modulated by antipsychotic medication as a function of treatment response. PMID:27336056

  18. High Field MRI Study on the Development of Fetal Brain Stem of 14-40 Weeks Gestational Age%14~40周胎儿脑干发育的高场强MRI研究

    Institute of Scientific and Technical Information of China (English)

    张英; 张忠和; 刘树伟; 田路; 樊慧丽; 刘群星; 来洪建

    2011-01-01

    long diameter of the pons; line G: length of long diameter of the medulla. Results : Each diameter linearly increased with gestational age. The slopes of lines suggested that the internal structures of the brain stem grew at different rates. Line F grew fastest, and line D grew slowest. Line A and line E almost had the same growth rate, line B and line F also had the same growth rate.Conclusions:High field MRI can clearly show the anatomy of fetal brain stem. The results of this study can provide a morphological reference for the assessment of normal fetal brain stem development in clinical settings.

  19. Biophysical modeling of high field diffusion MRI demonstrates micro-structural aberration in chronic mild stress rat brain

    DEFF Research Database (Denmark)

    Khan, Ahmad Raza; Chuhutin, Andrey; Wiborg, Ove;

    2016-01-01

    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...

  20. 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.

  1. 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.

  2. 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

  3. MRI brain in monohalomethane toxic encephalopathy: A case report

    Directory of Open Access Journals (Sweden)

    Yogeshwari S Deshmukh

    2013-01-01

    Full Text Available Monohalomethanes are alkylating agents that have been used as methylating agents, laboratory reagents, refrigerants, aerosol propellants, pesticides, fumigants, fire-extinguishing agents, anesthetics, degreasers, blowing agents for plastic foams, and chemical intermediates. Compounds in this group are methyl chloride, methyl bromide, methyl iodide (MI, and methyl fluoride. MI is a colorless volatile liquid used as a methylating agent to manufacture a few pharmaceuticals and is also used as a fumigative insecticide. It is a rare intoxicant. Neurotoxicity is known with both acute and chronic exposure to MI. We present the characteristic magnetic resonance imaging (MRI brain findings in a patient who developed neuropsychiatric symptoms weeks after occupational exposure to excessive doses of MI.

  4. 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.

  5. Men fear other men most: Gender specific brain activations in perceiving threat from dynamic faces and bodies. An fMRI study.

    Directory of Open Access Journals (Sweden)

    Mariska Esther Kret

    2011-01-01

    Full Text Available Gender differences are an important factor regulating daily interactions. Using functional magnetic resonance imaging (fMRI we show that areas involved in processing social signals are activated differently by threatening signals send from male or female facial and bodily expressions and these activity patterns are different for male and female participants. Male participants pay more attention to the female face as shown by increased amygdala activity. But a host of other areas indicate a selective sensitivity for male observers attending to male bodily expressions (extrastriate body area, superior temporal sulcus, fusiform gyrus, pre-supplementary motor area and premotor cortex. This is the first study investigating gender differences in processing dynamic female and male facial and bodily expressions and it illustrates the importance of gender differences in affective communication.

  6. O7.02RADIOSURGERY AND BRAIN METASTASES: ADEQUATE SEQUENCE OF BRAIN MRI CAN SIGNIFICANTLY CHANGE THE INTRACRANIAL DISEASE STAGING

    Science.gov (United States)

    Scoccianti, S.; Greto, D.; Bordi, L.; Bono, P.; Pecchioli, G.; Casati, M.; Vanzi, E.; Compagnucci, A.; Gadda, D.; Livi, L.

    2014-01-01

    INTRODUCTION: Accurate assessment of the exact number of brain metastases is of utmost importance in the decision-making process for the appropriate treatment. The diagnostic efficacy in the detection of additional brain metastases of a double dose contrast three-dimensional, T1-Weighted Gradient-Echo Imaging was evaluated. METHODS: Before undergoing radiosurgical treatment, patients underwent a brain magnetic resonance imaging (MRI) scan to be used during the treatment planning in order to contour the targets and to locate the brain lesions as they relate to the stereotactic frame. All the patients underwent a post-contrast study with T1-weighted, 3D Magnetization-Prepared Rapid Acquisition Gradient Echo (MP RAGE) sequence. We used a double dose of gadobenate dimeglumine and slice thickness of 0.9 mm. RESULTS: Starting from October 2012 to February 2014, we treated with Gamma Knife radiosurgery (GKRS) 62 patients with brain metastases. On the diagnostic MRI, all the patients had a number of lesions ≤4. Median time interval between diagnostic MRI scan and the day of GKRS was 11 days (range 5-20) A total of 54 additional lesions were detected on MR imaging performed in the same day of the GKRS in twenty-two patients out of 62 (35.5%). A median number of 2 additional lesions were detected (range 1-8). Among these 22 patients only 14 patients had a number of lesions ≤4 on the day of treatment. Patients with a total number of lesions ≤10 were treated with GKRS. Two patients with a total number of lesions > 10 were treated with whole brain radiotherapy (WBRT). CONCLUSIONS: A double-contrast study with T1-weighted, volumetric MPRAGE sequence may offer better staging for patients with brain metastases. In our opinion, it should be recommended in all the patients with newly diagnosed brain metastases because the detection of the real number of lesions is crucial for an adequate treatment and it also may lead to choose different therapeutic strategies.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Stacking denoising auto-encoders in a deep network to segment the brainstem on MRI in brain cancer patients: A clinical study.

    Science.gov (United States)

    Dolz, Jose; Betrouni, Nacim; Quidet, Mathilde; Kharroubi, Dris; Leroy, Henri A; Reyns, Nicolas; Massoptier, Laurent; Vermandel, Maximilien

    2016-09-01

    Delineation of organs at risk (OARs) is a crucial step in surgical and treatment planning in brain cancer, where precise OARs volume delineation is required. However, this task is still often manually performed, which is time-consuming and prone to observer variability. To tackle these issues a deep learning approach based on stacking denoising auto-encoders has been proposed to segment the brainstem on magnetic resonance images in brain cancer context. Additionally to classical features used in machine learning to segment brain structures, two new features are suggested. Four experts participated in this study by segmenting the brainstem on 9 patients who underwent radiosurgery. Analysis of variance on shape and volume similarity metrics indicated that there were significant differences (p<0.05) between the groups of manual annotations and automatic segmentations. Experimental evaluation also showed an overlapping higher than 90% with respect to the ground truth. These results are comparable, and often higher, to those of the state of the art segmentation methods but with a considerably reduction of the segmentation time. PMID:27236370

  12. 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.

  13. 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.)

  14. 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)

  15. Incidental brain lesions on MRI in the depressive elderly

    Energy Technology Data Exchange (ETDEWEB)

    Iidaka, Tetsuya (Kanto-Teishin Hospital, Tokyo (Japan))

    1994-07-01

    The study was designed to determine the correlation between parenchymal lesions on MRI and depression. Thirty patients with depression satisfying the following criteria were selected: (1) 60 years or over at the time of MRI scanning, (2) no evidence of cerebrovascular disorder or dementia, and (3) no evidence of neurological findings such as extremity palsy. Seventy six patients with no history of psychiatric visits to a clinic served as controls. There was no significant difference in risk factors for cerebrovascular disorders, such as hypertension, diabetes mellitus, and ischemic heart disease, between the depressive group and the control group. MRI manifestations were semiquantitatively scored according to the periventricular hyperintensity (PVH), white matter hyperintensity (WMH), and pons hyperintensity (PH). All of the PVH score, WMH score, and cerebral enlargement index correlated with age. Although there was no significant difference in the incidence of various findings between the depressive group and the control group, the incidence of PVH was significantly higher in the depressive group than the control group. Both the incidence of PVH and the transverse diameter of the third ventricle were significantly higher in the degressive group than the control group, even considering the age, sex, and risk factors. An enlargement of cerebral ventricle was noticeable especially in patients given antidepressant agents. In conclusion, depression seen in elderly people seemed to be attributable to parenchymal lesions. (N.K.).

  16. Incidental brain lesions on MRI in the depressive elderly

    International Nuclear Information System (INIS)

    The study was designed to determine the correlation between parenchymal lesions on MRI and depression. Thirty patients with depression satisfying the following criteria were selected: (1) 60 years or over at the time of MRI scanning, (2) no evidence of cerebrovascular disorder or dementia, and (3) no evidence of neurological findings such as extremity palsy. Seventy six patients with no history of psychiatric visits to a clinic served as controls. There was no significant difference in risk factors for cerebrovascular disorders, such as hypertension, diabetes mellitus, and ischemic heart disease, between the depressive group and the control group. MRI manifestations were semiquantitatively scored according to the periventricular hyperintensity (PVH), white matter hyperintensity (WMH), and pons hyperintensity (PH). All of the PVH score, WMH score, and cerebral enlargement index correlated with age. Although there was no significant difference in the incidence of various findings between the depressive group and the control group, the incidence of PVH was significantly higher in the depressive group than the control group. Both the incidence of PVH and the transverse diameter of the third ventricle were significantly higher in the degressive group than the control group, even considering the age, sex, and risk factors. An enlargement of cerebral ventricle was noticeable especially in patients given antidepressant agents. In conclusion, depression seen in elderly people seemed to be attributable to parenchymal lesions. (N.K.)

  17. 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

  18. 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.)

  19. Tl-201 and Tc-99m-Sestamibi SPECT for brain tumor detection: Comparison using MRI coregistration

    Energy Technology Data Exchange (ETDEWEB)

    Darcourt, J.; Itti, L.; Chang, L. [UCLA Medical Center, Torrance, CA (United States)] [and others

    1994-05-01

    Tl-201 (Tl) brain SPECT has been validated for the differential diagnosis of high versus low grade gliomas and recurrence versus radiation necrosis. We compared this technique to Tc-99m-Sestamibi (MIBI) SPECT in 9 patients (pts) with brain tumors using MRI coregistration. Pts were injected with 4 mCi of Tl and brain SPECT was performed using a dedicated brain system. This was immediately following by an injection of 20 mCi of MIBI and a brain SPECT using the same camera and with the pt in the same position. Four pts were studied for the diagnosis of radiation necrosis vs. tumor recurrence (2 had biopsy proven recurrence); 5 pts were studied for primary tumor evaluation: 2 meningiomas, 1 oligodendroglioma, 1 low-grade astrocytoma, 1 cysticercosis. Coregistration was performed for every pt by 3D surface fitting of the inner skull MIBI contour to the MRI brain surface extracted automatically. ROIs were drawn on the MRI and applied to the coregistered MIBI and Tl images for tumor to non-tumor ratios T/NT calculations. There was a tight correlation between MIBI and Tl T/NT (r-0.96) and a 1.5 threshold separated radiation necrosis from recurrence and low from high grade primary tumors. Therefore, the data already available on Tl brain tumor imaging can be used with MIBI SPECT with the advantage of a better image quality (2.5 to 4 times more counts).

  20. 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.

  1. Using concurrent EEG and fMRI to probe the state of the brain in schizophrenia.

    Science.gov (United States)

    Ford, Judith M; Roach, Brian J; Palzes, Vanessa A; Mathalon, Daniel H

    2016-01-01

    Perceptional abnormalities in schizophrenia are associated with hallucinations and delusions, but also with negative symptoms and poor functional outcome. Perception can be studied using EEG-derived event related potentials (ERPs). Because of their excellent temporal resolution, ERPs have been used to ask when perception is affected by schizophrenia. Because of its excellent spatial resolution, functional magnetic resonance imaging (fMRI) has been used to ask where in the brain these effects are seen. We acquired EEG and fMRI data simultaneously to explore when and where auditory perception is affected by schizophrenia. Thirty schizophrenia (SZ) patients and 23 healthy comparison subjects (HC) listened to 1000 Hz tones occurring about every second. We used joint independent components analysis (jICA) to combine EEG-based event-related potential (ERP) and fMRI responses to tones. Five ERP-fMRI joint independent components (JIC) were extracted. The "N100" JIC had temporal weights during N100 (peaking at 100 ms post-tone onset) and fMRI spatial weights in superior and middle temporal gyri (STG/MTG); however, it did not differ between groups. The "P200" JIC had temporal weights during P200 and positive fMRI spatial weights in STG/MTG and frontal areas, and negative spatial weights in the nodes of the default mode network (DMN) and visual cortex. Groups differed on the "P200" JIC: SZ had smaller "P200" JIC, especially those with more severe avolition/apathy. This is consistent with negative symptoms being related to perceptual deficits, and suggests patients with avolition/apathy may allocate too few resources to processing external auditory events and too many to processing internal events. PMID:27622140

  2. 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...

  3. 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...

  4. 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.

  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. Can Musical Training Influence Brain Connectivity? Evidence from Diffusion Tensor MRI

    Directory of Open Access Journals (Sweden)

    Emma Moore

    2014-06-01

    Full Text Available In recent years, musicians have been increasingly recruited to investigate grey and white matter neuroplasticity induced by skill acquisition. The development of Diffusion Tensor Magnetic Resonance Imaging (DT-MRI has allowed more detailed investigation of white matter connections within the brain, addressing questions about the effect of musical training on connectivity between specific brain regions. Here, current DT-MRI analysis techniques are discussed and the available evidence from DT-MRI studies into differences in white matter architecture between musicians and non-musicians is reviewed. Collectively, the existing literature tends to support the hypothesis that musical training can induce changes in cross-hemispheric connections, with significant differences frequently reported in various regions of the corpus callosum of musicians compared with non-musicians. However, differences found in intra-hemispheric fibres have not always been replicated, while findings regarding the internal capsule and corticospinal tracts appear to be contradictory. There is also recent evidence to suggest that variances in white matter structure in non-musicians may correlate with their ability to learn musical skills, offering an alternative explanation for the structural differences observed between musicians and non-musicians. Considering the inconsistencies in the current literature, possible reasons for conflicting results are offered, along with suggestions for future research in this area.

  7. Classification of First-Episode Schizophrenia Patients and Healthy Subjects by Automated MRI Measures of Regional Brain Volume and Cortical Thickness

    OpenAIRE

    Yoichiro Takayanagi; Tsutomu Takahashi; Lina Orikabe; Yuriko Mozue; Yasuhiro Kawasaki; Kazue Nakamura; Yoko Sato; Masanari Itokawa; Hidenori Yamasue; Kiyoto Kasai; Masayoshi Kurachi; Yuji Okazaki; Michio Suzuki

    2011-01-01

    BACKGROUND: Although structural magnetic resonance imaging (MRI) studies have repeatedly demonstrated regional brain structural abnormalities in patients with schizophrenia, relatively few MRI-based studies have attempted to distinguish between patients with first-episode schizophrenia and healthy controls. METHOD: Three-dimensional MR images were acquired from 52 (29 males, 23 females) first-episode schizophrenia patients and 40 (22 males, 18 females) healthy subjects. Multiple brain measure...

  8. 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.)

  9. Basilar artery fenestration - correlative MRI and neurosonographic study

    International Nuclear Information System (INIS)

    The aim of the study is to demonstrate a rare case of congenital basilar artery fenestration using neuroimaging methods. A 58-year-old man with an isolated lesion of the right n. oculomotorius was examined with brain MRI/MRA and multimodal neurosonography. A typical fenestration was detected on MRA in the proximal portion of the basilar artery immediately after the fusion of the vertebral arteries, it was correlated with ultrasound pattern - a parallel blood flow image and retrograde flow velocity curves were obtained from the fenestrated segments of a. basilaris. Imaging (MRI/MPA and ultrasonic) methods are useful for non-invasive diagnosis of basilar artery fenestration, which in the past was proved only by conventional cerebral angiography or autopsy. (authors) Key words: Fenestration. Basilar Artery. MRI. NEUROSONOGRAPHY

  10. Outcome Classification of Preschool Children with Autism Spectrum Disorders Using Mri Brain Measures.

    Science.gov (United States)

    Akshoomoff, Natacha; Lord, Catherine; Lincoln, Alan J.; Courchesne, Rachel Y.; Carper, Ruth A.; Townsend, Jeanne; Courchesne, Eric

    2004-01-01

    Objective: To test the hypothesis that a combination of magnetic resonance imaging (MRI) brain measures obtained during early childhood distinguish children with autism spectrum disorders (ASD) from typically developing children and is associated with functional outcome. Method: Quantitative MRI technology was used to measure gray and white matter…

  11. Brain Decoding-Classification of Hand Written Digits from fMRI Data Employing Bayesian Networks

    Science.gov (United States)

    Yargholi, Elahe'; Hossein-Zadeh, Gholam-Ali

    2016-01-01

    We are frequently exposed to hand written digits 0–9 in today's modern life. Success in decoding-classification of hand written digits helps us understand the corresponding brain mechanisms and processes and assists seriously in designing more efficient brain–computer interfaces. However, all digits belong to the same semantic category and similarity in appearance of hand written digits makes this decoding-classification a challenging problem. In present study, for the first time, augmented naïve Bayes classifier is used for classification of functional Magnetic Resonance Imaging (fMRI) measurements to decode the hand written digits which took advantage of brain connectivity information in decoding-classification. fMRI was recorded from three healthy participants, with an age range of 25–30. Results in different brain lobes (frontal, occipital, parietal, and temporal) show that utilizing connectivity information significantly improves decoding-classification and capability of different brain lobes in decoding-classification of hand written digits were compared to each other. In addition, in each lobe the most contributing areas and brain connectivities were determined and connectivities with short distances between their endpoints were recognized to be more efficient. Moreover, data driven method was applied to investigate the similarity of brain areas in responding to stimuli and this revealed both similarly active areas and active mechanisms during this experiment. Interesting finding was that during the experiment of watching hand written digits, there were some active networks (visual, working memory, motor, and language processing), but the most relevant one to the task was language processing network according to the voxel selection. PMID:27468261

  12. 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.)

  13. Walking and periventricular leukomalacia: locomotor characteristics and brain imaging (MRI).

    NARCIS (Netherlands)

    Ledebt, A.; Savelsbergh, G.J.; Sie, L.T.L.; Knaap, M.S. van der

    2008-01-01

    The aim of the present study was to compare the walking abilities in infants with and without periventricular leukomalacia and to see whether the severity of the brain damage was related to locomotor outcome of the infants at 12 and 18 months. 47 newborns were included in the study based on white ma

  14. Quantitative evaluation of brain development using anatomical MRI and diffusion tensor imaging☆

    OpenAIRE

    Oishi, Kenichi; Faria, Andreia V.; Yoshida, Shoko; Chang, Linda; Mori, Susumu

    2013-01-01

    The development of the brain is structure-specific, and the growth rate of each structure differs depending on the age of the subject. Magnetic resonance imaging (MRI) is often used to evaluate brain development because of the high spatial resolution and contrast that enable the observation of structure-specific developmental status. Currently, most clinical MRIs are evaluated qualitatively to assist in the clinical decision-making and diagnosis. The clinical MRI report usually does not provi...

  15. Neural Changes following Behavioral Activation for a Depressed Breast Cancer Patient: A Functional MRI Case Study

    OpenAIRE

    Gawrysiak, Michael J.; John P. Carvalho; Rogers, Baxter P.; Nicholas, Christopher R. N.; Dougherty, John H.; Hopko, Derek R.

    2012-01-01

    Functional neuroimaging is an innovative but at this stage underutilized method to assess the efficacy of psychotherapy for depression. Functional magnetic resonance imaging (fMRI) was used in this case study to examine changes in brain activity in a depressed breast cancer patient receiving an 8-session Behavioral Activation Treatment for Depression (BATD), based on the work of Hopko and Lejuez (2007). A music listening paradigm was used during fMRI brain scans to assess reward responsivenes...

  16. 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

  17. 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 .

  18. Study of brain activation during the complicated hand motor task (Luria's fist-edge-palm test) by functional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Umetsu, Atsushi; Takahashi, Shoki; Higano, Shuichi [Tohoku Univ., Sendai, Miyagi (Japan). Graduate School of Medicine] (and others)

    2000-11-01

    The fist-edge-palm test (FEP) was introduced by Luria to detect dynamic apraxia. Luria believed its impairment was closely related to contralateral frontal lobe damage. However, this presumption still remains controversial. In this study, we applied this test to normal subjects and confirmed the activation in the whole brain. The subjects were instructed to perform the FEP, fist-palm, palm-edge, and fist-edge tasks with their right hand, and control state with no voluntary movement during the scan. The contralateral precentral, postcentral, premotor, supplementary motor, and parietal association areas and bilateral cerebellum were activated commonly in each task. The percentage of change in signal intensity was greater in the contralateral premotor and parietal association areas and bilateral cerebellum during the FEP than the other tasks. We suspected that these areas played an important role for executing the FEP with right hand. (author)

  19. 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 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 T1-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...

  20. A COMPARATIVE STUDY ON THE CT AND MRI IN THE DIAGNOSIS OF ACUTE BRAIN INJURY%CT与MRI在急性颅脑损伤诊断中的比较研究

    Institute of Scientific and Technical Information of China (English)

    付振杰; 付瑜莹

    2011-01-01

    [Objective] To compare CT and MRI in the diagnosis of acute brain injury clinical value. [Methods] In our hospital from July 2008 to July 2010, 60 patients with acute brain injury were collected. 30 patients were treated with CT, 30 cases were tested with MRI examination. We compared the positive rate and abnormal prognosis and abnormal parts of the two methods. [Results] The positive rate of abnormal part detected by MRI examination was significantly higher than that of CT examination, and the sites of brain injury detected by MRI examination was significantly higher than that of CT examination (P < 0.05). [Conclusion] Application of MRI examination has good advantage in diagnosis of brain injury detected by CT.%[目的]比较CT与MRI在急性颅脑损伤诊断中的临床价值.[方法]选择我院2008年7月~2010年7月收治的60例急性颅脑损伤患者作为观察对象,其中30例应用CT检查,30例应用MRI检查,比较两组检查方法发现异常的阳性率及预后以及两种检查方法发现异常的部位.[结果]应用MRI检查发现异常的阳性率明显高于CT检查,且发现颅脑损伤的部位也多于CT检查(P< 0.05).[结论]应用MRI检查颅脑损伤具有较好的诊断优势,明显优于应用CT检查.

  1. 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.

  2. Leptomeningeal metastasis: a CT and MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Oschmann, P. [Dept. of Neurology, Univ. of Giessen (Germany); Bauer, T. [Dept. of Radiology, Univ. of Giessen (Germany); Kaps, M. [Dept. of Neurology, Univ. of Giessen (Germany); Trittmacher, S. [Dept. of Radiology, Univ. of Giessen (Germany); Dorndorf, W. [Dept. of Neurology, Univ. of Giessen (Germany)

    1994-08-01

    We evaluated 35 patients with leptomeningeal metastasis (LM) that was proved by repeated positive cytology (33 patients) and/or autopsy (10 patients) with T1-weighted Gadolinium-DTPA-enhanced MRI and contrast-enhanced CT. The patients (20 women and 15 men) ranged in age from 5-77 years (mean 56 years). Tumour histology included 26 carcinomas, 1 sarcoma, 6 leucaemias, 1 medulloblastoma and 1 primary CNS lymphoma. Intracranial abnormalities were noted in 58% of cases by CT and 88% by MRI, and included hydrocephalus, meningeal or ependymal enhancement, subarachnoidal or intraparenchymal nodules. Leptomeningeal metastasis was detected by MRI in 13 of 17 examined patients, including the three cases with a positive CT. It was proved that MRI is equal or superior to CT in demonstrating meningeal or ependymal enhancement and quantifying enhanced subarachnoidal or parenchymal nodules. However, in the evaluation of leptomeningeal metastasis both modalities had a high incidence of false-negative studies, 89% (31 of 35) by CT and 24% (4 of 17) by MRI. In contrast, two patients with initially negative cytology had pathological MRI findings. Our data indicate that Gadolinium-enhanced MRI is the preferred imaging modality in leptomeningeal metastasis, and suggest that CT does not add significant additional information. However, LM is primarily a histological diagnosis by detecting tumour cells in the cerebrospinal fluid. (orig.)

  3. MRI diagnosis of brain metastases%脑转移瘤的MRI诊断

    Institute of Scientific and Technical Information of China (English)

    贾福艳; 宋伟兴; 白振武

    2012-01-01

    目的 研究脑转移瘤的MRI表现,探讨其对脑转移瘤的诊断价值.方法 回顾分析经临床及病理证实的脑转移瘤50例,所有的病例均行颅脑MRI平扫及增强扫描,都包括T1WI、T2WI、FLAIR及DWI.结果 50例脑转移瘤中单发12例,多发38例;其中MRI平扫T1WI发现病灶95个,平扫FLAIR发现病灶120个,增强T1WI发现病灶156个,增强FLAIR发现病灶192个.结论 MRI增强扫描比平扫能发现更多的脑转移瘤病灶,尤其是增强FLAIR序列;脑转移瘤MRI表现具有一定的特征性,结合临床病史大部分能做出正确诊断.%Objective To study the MRI manifestation of brain metastasis, and to discuss the diagnostic value of brain metastasis. Methods The clinical data of fifty patients with clinically and pathologically proved brain metastasis was retrospectively analyzed. Plain MRI scan and enhanced MRI scan were performed in all the cases, including T1WI、T2WI、FLAIR and DWI. Results There were 12 cases of single focus and 38 cases of multiple foci, a total of 192 foci. Non-enhanced T1WI images, non-enhanced FLAIR images, enhanced T1W images and enhanced FLAIR images showed 95 foci, 120 foci, 156 foci, and 192 foci, respectively. Conclusion Enhanced MR images are significantly more efficient than non-enhanced MR images in the diagnosis of brain metastatic foci, especially enhanced FLAIR images. Brain metastases can be diagnosed correctly according to the MRI characteristic findings combined with disease history of the patients.

  4. Altered intrinsic regional brain spontaneous activity and subjective sleep quality in patients with chronic primary insomnia: a resting-state fMRI study

    Directory of Open Access Journals (Sweden)

    Dai XJ

    2014-11-01

    Full Text Available Xi-Jian Dai,1,2 De-Chang Peng,1 Hong-Han Gong,1 Ai-Lan Wan,3 Xiao Nie,1 Hai-Jun Li,1 Yi-Xiang J Wang2 1Department of Radiology, The First Affiliated Hospital of Nanchang University, Nangchang, Jiangxi, People’s Republic of China; 2Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong; 3Department of Psychosomatic Medicine, the First Affiliated Hospital of Nangchang University, Nangchang, Jiangxi, People’s Republic of China Study objective: To prospectively explore the underlying regional homogeneity (ReHo brain-activity deficit in patients with chronic primary insomnia (PCPIs and its relationship with clinical features.Design: The ReHo method and Statistical Parametric Mapping 8 software were used to evaluate whether resting-state localized brain activity was modulated between PCPIs and good sleepers (GSs, and correlation analysis between altered regional brain areas and clinical features was calculated. Patients and participants: Twenty-four PCPIs (17 females, seven males and 24 (12 females, 12 males age-, sex-, and education-matched GSs.Measurements and results: PCPIs disturbed subjective sleep quality, split positive mood, and exacerbated negative moods. Compared with GSs, PCPIs showed higher ReHo in left fusiform gyrus, and lower ReHo in bilateral cingulate gyrus and right cerebellum anterior lobe. Compared with female GSs, female PCPIs showed higher ReHo in the left fusiform gyrus and right posterior cingulate, and lower ReHo in the left cerebellum anterior lobe and left superior frontal gyrus. Compared with male GSs, male PCPIs showed higher ReHo in the right temporal lobe and lower ReHo in the bilateral frontal lobe. The fusiform gyrus showed strong positive correlations and the frontal lobe showed negative correlations with the clinical measurements.Conclusion: The ReHo analysis is a useful noninvasive imaging tool for the detection of cerebral changes and

  5. Transient enlargement of contrast uptake on MRI after linear accelerator (linac) stereotactic radiosurgery for brain metastases

    International Nuclear Information System (INIS)

    Purpose/Objective: With the increasing number of patients successfully treated with stereotactic radiosurgery for brain metastases, decision making after therapy based on follow-up imaging findings becomes more and more important. Magnetic resonance imaging (MRI) is the most sensitive means for follow-up studies. The objective of this study was to investigate the treatment outcome of our radiosurgery program and to describe the response of brain metastases to contrast-enhanced MRI after linear accelerator (linac) stereotactic radiosurgery and identify factors to distinguish among local control and local failure. Methods and Materials: Using serial MRI, we followed the course of 87 brain metastases in 48 consecutive patients treated between September 1996 and November 1997 with linac-based radiosurgery with 15-MV photons. Treatment planning was performed on an MR data cube. For spherical metastases, radiosurgery was delivered using a 9 noncoplanar arc technique with circular-shaped collimators. For irregularly shaped targets, radiosurgery was delivered using a manually driven multi-leaf collimator with a leaf width of 1.5 mm projected to the isocenter. Median radiosurgery dose was 20 Gy prescribed to the 80% isodose. Together with whole brain radiotherapy (20x2 Gy, 5/w), a median radiosurgical dose of 15 Gy was delivered. Median follow-up was 8 (range 2-36) months. Factors influencing local control and survival rates were analyzed with respect to MRI response, and Kaplan-Meier curves were calculated. Results: Actuarial local tumor control was 91% at one and two years. Patient survival at one and two years was 30% and 18%. Median survival was 9 months. During follow-up in 70 (81%) of the 87 treated metastases, the contrast-enhancing volumes on T1W images were stable or disappeared partly or completely. A transient enlargement of contrast-enhancing volumes was observed in 11 (12%) of the 87 lesions treated, while a progressive enlargement due to local treatment

  6. O7.02RADIOSURGERY AND BRAIN METASTASES: ADEQUATE SEQUENCE OF BRAIN MRI CAN SIGNIFICANTLY CHANGE THE INTRACRANIAL DISEASE STAGING

    OpenAIRE

    Scoccianti, S.; Greto, D.; L. Bordi; Bono, P.; Pecchioli, G.; Casati, M; E. Vanzi; Compagnucci, A; Gadda, D.; Livi, L.

    2014-01-01

    INTRODUCTION: Accurate assessment of the exact number of brain metastases is of utmost importance in the decision-making process for the appropriate treatment. The diagnostic efficacy in the detection of additional brain metastases of a double dose contrast three-dimensional, T1-Weighted Gradient-Echo Imaging was evaluated. METHODS: Before undergoing radiosurgical treatment, patients underwent a brain magnetic resonance imaging (MRI) scan to be used during the treatment planning in order to c...

  7. 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.

  8. Longitudinal morphometric MRI study of Alzheimer's disease

    International Nuclear Information System (INIS)

    A longitudinal morphometric MRI study of Alzheimer's disease (AD) was conducted to determine the relationship between the progression of the symptoms and the progression of the brain atrophy. The Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD), developed by Matsuda et al. was used as a method of morphometry to perform the statistical MR image analysis. Thirty-eight patients of AD patients were investigated with VSRAD. These patients were divided into two groups according to the progression of symptoms based on a clinical evaluation. One group was the progress group (20 patients), while the other group was the stable group (18 patients) for comparison. The relationship was investigated between the speed of the symptomatic progression and the change in each VSRAD indicator. Consequently, the entorhinal Z-score and the entorhinal atrophy rate showed a correlation with the speed of the symptomatic progression. The increase of the entorhinal Z-score in the follow-up was larger in the progress group than that in the stable group (0.65/1.28 years in the progress group and 0.05/1.26 years in the stable group.). These results suggest that a rapid symptomatic progression in an AD patient accompanies the rapid progression of atrophy in the entorhinal cortex. (author)

  9. 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

  10. 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

  11. 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

  12. Diagnostic value of low-field MRI for acute poisoning brain injury

    International Nuclear Information System (INIS)

    Objective: To investigate the value of low-field MIR in diagnosis of acute CO poisoning brain injury. Methods: The brain MIR and clinical data of 110 patients with acute CO poisoning brain injury confirmed by clinical examination were retrospectively analyzed. Results: Long T1 and T2 signal intensity was showed on MRI in cerebral hemispheres and globus pallidus symmetrically. There were three basic types of MIR manifestations, white matter of brain type, globus pallidus type and brain mixed type. Conclusions: MRI could be used for confirming the degree and range of acute CO poisoning brain injury. It has important clinical value in the diagnosis, staging and prognosis of patients with acute CO poisoning brain injury. (authors)

  13. Diffusion-weighted MRI and proton MR spectroscopy in adult hypoxic brain injury

    International Nuclear Information System (INIS)

    Full text: The clinical and imaging assessment of patients with severe hypoxic brain injury is difficult, especially in the first few days after the insult. Proton spectroscopy has shown promise in the assessment of neonatal hypoxic brain injury, but there has been little experience with it in adults with such injury. The high sensitivity of diffusion-weighted imaging (DWI) for early stroke suggests that it may be more sensitive to hypoxic injury than conventional sequences. Patients with documented acute hypoxic episodes (cardiac arrest, hanging, measured severe arterial hypotension) and clinical evidence of hypoxic brain injury were included. MRI was not performed until sedation had been ceased for at least 24 hours. In addition to conventional T2-weighted and FLAIR imaging, six patients underwent DWI. A further ten patients underwent conventional imaging plus DWI and proton spectroscopy (PRESS TE 135, 2 x 2 x 2 cm voxel in parasagittal occipital cortex antero-inferiorly). Three of these patients were examined twice because of ongoing radiological and clinical uncertainty. In acute hypoxic insults, a negative diffusion-weighted study does not exclude significant brain injury. Proton spectroscopy is more sensitive to hypoxic brain injury, at least from 48 hours post-ictus, and may provide an index of severity. The findings suggest that acute hypoxia can trigger ongoing neuronal loss (over at least a week) without evidence of macroscopic infarction. Copyright (2002) Blackwell Science Pty Ltd

  14. 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

  15. Which fMRI clustering gives good brain parcellations?

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    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.

  16. 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.)

  17. 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

  18. 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.

  19. 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.

  20. Miliary brain metastases from papillary adenocarcinoma of the lung – unusual MRI pattern with histopathologic correlation

    International Nuclear Information System (INIS)

    Miliary brain metastases are very rarely described in the literature but if they are, they are quite obvious on magnetic resonance imaging (MRI) and enhance after intravenous administration of the contrast medium. The authors presented a case of miliary metastatic spread to the brain which was invisible on computed tomography and hardly visible on MRI, i.e. as countless, tiny, slightly T1-hyperintense foci that did not enhance. The authors discussed a few T1-hyperintense brain lesions which did not include metastases (except for metastatic melanoma which was a radiological suggestion after brain MRI). Autopsy revealed papillary adenocarcinoma of the lung with numerous metastatic lesions in both cerebral and cerebellar hemispheres and the meninges

  1. Segmentation and Classification of Brain MRI Images Using Improved Logismos-B Algorithm

    Directory of Open Access Journals (Sweden)

    S. Dilip kumar

    2014-12-01

    Full Text Available Automated reconstruction and diagnosis of brain MRI images is one of the most challenging problems in medical imaging. Accurate segmentation of MRI images is a key step in contouring during radiotherapy analysis. Computed tomography (CT and Magnetic resonance (MR imaging are the most widely used radiographic techniques in diagnosis and treatment planning. Segmentation techniques used for the brain Magnetic Resonance Imaging (MRI is one of the methods used by the radiographer to detect any abnormality specifically in brain. The method also identifies important regions in brain such as white matter (WM, gray matter (GM and cerebrospinal fluid spaces (CSF. These regions are significant for physician or radiographer to analyze and diagnose the disease. We propose a novel clustering algorithm, improved LOGISMOS-B to classify tissue regions based on probabilistic tissue classification, generalized gradient vector flows with cost and distance function. The LOGISMOS graph segmentation framework. Expand the framework to allow regionally-aware graph construction and segmentation

  2. Test-retest reliability of graph metrics of resting state MRI functional brain networks: A review.

    Science.gov (United States)

    Andellini, Martina; Cannatà, Vittorio; Gazzellini, Simone; Bernardi, Bruno; Napolitano, Antonio

    2015-09-30

    The employment of graph theory to analyze spontaneous fluctuations in resting state BOLD fMRI data has become a dominant theme in brain imaging studies and neuroscience. Analysis of resting state functional brain networks based on graph theory has proven to be a powerful tool to quantitatively characterize functional architecture of the brain and it has provided a new platform to explore the overall structure of local and global functional connectivity in the brain. Due to its increased use and possible expansion to clinical use, it is essential that the reliability of such a technique is very strongly assessed. In this review, we explore the outcome of recent studies in network reliability which apply graph theory to analyze connectome resting state networks. Therefore, we investigate which preprocessing steps may affect reproducibility the most. In order to investigate network reliability, we compared the test-retest (TRT) reliability of functional data of published neuroimaging studies with different preprocessing steps. In particular we tested influence of global signal regression, correlation metric choice, binary versus weighted link definition, frequency band selection and length of time-series. Statistical analysis shows that only frequency band selection and length of time-series seem to affect TRT reliability. Our results highlight the importance of the choice of the preprocessing steps to achieve more reproducible measurements. PMID:26072249

  3. Neuroimaging of language processes: fMRI of silent and overt lexical processing and the promise of multiple process imaging in single brain studies

    International Nuclear Information System (INIS)

    To implement and evaluate a multiple-process functional magnetic resonance imaging (fMRI) paradigm designed to effectively and efficiently activate several language-related regions for use with neurosurgical patients. Both overt and covert response conditions were examined. The fMRI experiments compared the traditional silent word-generation condition versus an overt one as they engage frontal language regions (Experiment 1) and silent versus overt semantic association conditions as they engage multiple language processing regions (Experiment 2). In Experiment 1 the overt condition yielded greater magnitude of activation, but not volume of activation, in the left inferior frontal and insular cortices than did the silent condition for most, but not all, participants. Experiment 2 demonstrated that the activation of multiple established language processing regions (ie, orthographic, phonological and semantic) can be achieved in a significant number of participants, particularly under overt semantic association conditions and that such activation varies in predictable ways. The traditional silent response condition cannot be considered as equivalent to the overt response condition during word generation or semantic association. The multiple-process imaging method introduced here was sensitive to processing robust orthographic, phonological, and semantic regions, particularly under the overt response condition. (author)

  4. MRI and pathological examination of post-mortem brains: the problem of white matter high signal areas

    Energy Technology Data Exchange (ETDEWEB)

    Scarpelli, M. (Inst. of Pathological Anatomy and Histopathology, Ancona Univ. (Italy)); Salvolini, U. (Magnetic Resonance Research Unit, Ancona Univ. (Italy)); Diamanti, L. (Inst. of Pathological Anatomy and Histopathology, Ancona Univ. (Italy)); Montironi, R. (Inst. of Pathological Anatomy and Histopathology, Ancona Univ. (Italy)); Chiaromoni, L. (Magnetic Resonance Research Unit, Ancona Univ. (Italy)); Maricotti, M. (Magnetic Resonance Research Unit, Ancona Univ. (Italy))

    1994-07-01

    We examined 21 brains from individuals more than 65 years of age by MRI and neuropathological methods to study the frequency and morphology of white matter changes. There were 16 brains from neurologically normal subjects (Group 1) while the remaining 5 (Group 2) had neurological disturbances. In Group 1 MRI showed high signal areas in the periventricular white matter in 12 brains and in the deep white matter in 9. All had focal areas, with confluent zones in 4; 3 cystic infarcts were also detected. Neuropathology in this Group showed periventricular changes of variable extent in all cases, vacuolated myelin around the perivascular spaces in 14 and degenerate myelin in 4. Macroscopic inspection showed 3 cystic lacunar infarcts, while areas of recent infarction were present on histology in 2. Four of the Group 2 brains had periventricular MRI changes; high signal areas in deep white matter were focal in 2 and confluent in 1. Cystic infarcts were detected in 3 cases. Neuropathology showed periventricular changes in all the brains; in 4 myelin around the perivascular spaces was vacuolated while degenerate myelin was demonstrated in 1. There were also old (1) and recent (2) lacunar infarcts. (orig.)

  5. 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.

  6. 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

  7. Evaluation of MRI and cannabinoid type 1 receptor PET templates constructed using DARTEL for spatial normalization of rat brains

    International Nuclear Information System (INIS)

    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 [18F]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 templates

  8. Challenges in Identifying the Foot Motor Region in Patients with Brain Tumor on Routine MRI: Advantages of fMRI

    Science.gov (United States)

    Fisicaro, R.A.; Jiao, R.X.; Stathopoulos, C.; Brennan, N.M. Petrovich; Peck, K.K.; Holodny, A.I.

    2016-01-01

    BACKGROUND AND PURPOSE Accurate localization of the foot/leg motor homunculus is essential because iatrogenic damage can render a patient wheelchair- or bed-bound. We hypothesized the following: 1) Readers would identify the foot motor homunculus <100% of the time on routine MR imaging, 2) neuroradiologists would perform better than nonradiologists, and 3) those with fMRI experience would perform better than those without it. MATERIALSANDMETHODS Thirty-five attending-level raters (24 neuroradiologists, 11 nonradiologists) evaluated 14 brain tumors involving the frontoparietal convexity. Raters were asked to identify the location of the foot motor homunculus and determine whether the tumor involved the foot motor area and/or motor cortex by using anatomic MR imaging. Results were compared on the basis of prior fMRI experience and medical specialty by using Mann-Whitney U test statistics. RESULTS No rater was 100% correct. Raters correctly identified whether the tumor was in the foot motor cortex 77% of the time. Raters with fMRI experience were significantly better than raters without experience at foot motor fMRI centroid predictions (13 ± 6 mm versus 20 ± 13 mm from the foot motor cortex center, P = 2 × 10−6) and arrow placement in the motor gyrus (67% versus 47%, P = 7 × 10−5). Neuroradiologists were significantly better than nonradiologists at foot motor fMRI centroid predictions (15 ± 8 mm versus 20 ± 14 mm, P = .005) and arrow placement in the motor gyrus (61% versus 46%, P = .008). CONCLUSIONS The inability of experienced readers to consistently identify the location of the foot motor homunculus on routine MR imaging argues for using fMRI in the preoperative setting. Experience with fMRI leads to improved accuracy in identifying anatomic structures, even on routine MR imaging. PMID:25882288

  9. Diffuse pachymeningeal enhancement on brain MRI: spontaneous intracranial hypotension and head trauma

    International Nuclear Information System (INIS)

    We evaluated the MRI finding of pachymeningeal enhancement in patients with intracranial hypotension and head trauma with particular attention to differential findings and change in follow-up study, and in order to support the knowledge about the pathophysiology of dural enhancement. The findings of enhanced brain MRI of fifteen patients who showed diffuse pachymeningeal enhancement were retrospectively examined. Seven of fifteen patients were finally diagnosed as spontaneous intracranial hypotension (SIH). Eight of fifteen patients had a recent history of head trauma. We analyzed the shape, thickness, continuity and extent of dural enhancement, and the others concerned with positive MR findings. We also analyzed findings suggested displacement of brain parenchyma-displacement of the iter and cerebellar tonsil, and flattening of the anterior aspect of the pons-. Four of seven patients with SIH and four of eight patients with head trauma, underwent follow-up MRI. In the follow-up study, the presence of resolving pachymeningeal enhancement and symptom improvement was investigated. In all cases of SIH, the dura showed diffuse, even 3(1mm thick, global and contiguous enhancement along both cerebral convexities, both tentoria, and the falx. Displacement of the iter was noted in six cases and flattening of the anterior aspect of the pons in five. Displacement of the cerebellar tonsil was noted in one case. Five of seven cases showed small amount of subdural fluid collection. In all cases of head trauma, the dura was enhanced diffusely and asymmetrically, and showed no contiguity. Its distribution was consistent with the locations of traumatic lesions. Displacement of the iter was noted in one case. In four cases of SIH, clinical symptoms had improved, and three showed complete resolution of dural enhancement, in one patient continuously showed partial dural enhancement. Four cases of head trauma showed complete resolution of dural enhancement. Reversible diffuse

  10. Novel MRI methodology to detect human whole-brain connectivity changes after ingestion of fructose or glucose

    Science.gov (United States)

    Tsao, Sinchai; Wilkins, Bryce; Page, Kathleen A.; Singh, Manbir

    2012-03-01

    A novel MRI protocol has been developed to investigate the differential effects of glucose or fructose consumption on whole-brain functional brain connectivity. A previous study has reported a decrease in the fMRI blood oxygen level dependent (BOLD) signal of the hypothalamus following glucose ingestion, but due to technical limitations, was restricted to a single slice covering the hypothalamus, and thus unable to detect whole-brain connectivity. In another previous study, a protocol was devised to acquire whole-brain fMRI data following food intake, but only after restricting image acquisition to an MR sampling or repetition time (TR) of 20s, making the protocol unsuitable to detect functional connectivity above 0.025Hz. We have successfully implemented a continuous 36-min, 40 contiguous slices, whole-brain BOLD acquisition protocol on a 3T scanner with TR=4.5s to ensure detection of up to 0.1Hz frequencies for whole-brain functional connectivity analysis. Human data were acquired first with ingestion of water only, followed by a glucose or fructose drink within the scanner, without interrupting the scanning. Whole-brain connectivity was analyzed using standard correlation methodology in the 0.01-0.1 Hz range. The correlation coefficient differences between fructose and glucose ingestion among targeted regions were converted to t-scores using the water-only correlation coefficients as a null condition. Results show a dramatic increase in the hypothalamic connectivity to the hippocampus, amygdala, insula, caudate and the nucleus accumben for fructose over glucose. As these regions are known to be key components of the feeding and reward brain circuits, these results suggest a preference for fructose ingestion.

  11. 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.

  12. 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.)

  13. Combined 3 Tesla MRI Biomarkers Improve the Differentiation between Benign vs Malignant Single Ring Enhancing Brain Masses

    Science.gov (United States)

    Salice, Simone; Esposito, Roberto; Ciavardelli, Domenico; delli Pizzi, Stefano; di Bastiano, Rossella; Tartaro, Armando

    2016-01-01

    Purpose To evaluate whether the combination of imaging biomarkers obtained by means of different 3 Tesla (3T) Magnetic Resonance Imaging (MRI) advanced techniques can improve the diagnostic accuracy in the differentiation between benign and malignant single ring-enhancing brain masses. Materials and Methods 14 patients presenting at conventional 3T MRI single brain mass with similar appearance as regard ring enhancement, presence of peri-lesional edema and absence of hemorrhage signs were included in the study. All lesions were histologically proven: 5 pyogenic abscesses, 6 glioblastomas, and 3 metastases. MRI was performed at 3 Tesla and included Diffusion Weighted Imaging (DWI), Dynamic Susceptibility Contrast -Perfusion Weighted Imaging (DSC-PWI), Magnetic Resonance Spectroscopy (MRS), and Diffusion Tensor Imaging (DTI). Imaging biomarkers derived by those advanced techniques [Cerebral Blood Flow (CBF), relative Cerebral Blood Volume (rCBV), relative Main Transit Time (rMTT), Choline (Cho), Creatine (Cr), Succinate, N-Acetyl Aspartate (NAA), Lactate (Lac), Lipids, relative Apparent Diffusion Coefficient (rADC), and Fractional Anisotropy (FA)] were detected by two experienced neuroradiologists in joint session in 4 areas: Internal Cavity (IC), Ring Enhancement (RE), Peri-Lesional edema (PL), and Contralateral Normal Appearing White Matter (CNAWM). Significant differences between benign (n = 5) and malignant (n = 9) ring enhancing lesions were tested with Mann-Withney U test. The diagnostic accuracy of MRI biomarkers taken alone and MRI biomarkers ratios were tested with Receiver Operating Characteristic (ROC) analysis with an Area Under the Curve (AUC) ≥ 0.9 indicating a very good diagnostic accuracy of the variable. Results Five MRI biomarker ratios achieved excellent accuracy: IC-rADC/PL-NAA (AUC = 1), IC-rADC/IC-FA (AUC = 0.978), RE-rCBV/RE-FA (AUC = 0.933), IC-rADC/RE-FA (AUC = 0.911), and IC-rADC/PL-FA (AUC = 0.911). Only IC-rADC achieved a very good

  14. Close relationship between fMRI signals and transient heart rate changes accompanying K-complex. Simultaneous EEG/fMRI study

    International Nuclear Information System (INIS)

    Combining functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) allows the investigation of spontaneous activities in the human brain. Recently, by using this technique, increases in fMRI signal accompanying transient EEG activities such as sleep spindles and slow waves were reported. Although these fMRI signal increases appear to arise as a result of the neural activities being reflected in the EEG, when the influence of physiological activities upon fMRI signals are taken into consideration, it is highly controversial that fMRI signal increases accompanying transient EEG activities reflect actual neural activities. In the present study, we conducted simultaneous fMRI and polysomnograph recording of 18 normal adults, to study the effect of transient heart rate changes after a K-complex on fMRI signals. Significant fMRI signal increase was observed in the cerebellum, the ventral thalamus, the dorsal part of the brainstem, the periventricular white matter and the ventricle (quadrigeminal cistern). On the other hand, significant fMRI signal decrease was observed only in the right insula. Moreover, intensities of fMRI signal increase that was accompanied by a K-complex correlated positively with the magnitude of heart rate changes after a K-complex. Previous studies have reported that K-complex is closely related with sympathetic nervous activity and that the attributes of perfusion regulation in the brain differ during wakefulness and sleep. By taking these findings into consideration, our present results indicate that a close relationship exists between a K-complex and the changes in cardio- and neurovascular regulations that are mediated by the autonomic nervous system during sleep; further, these results indicate that transient heart rate changes after a K-complex can affect the fMRI signal generated in certain brain regions. (author)

  15. 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.

  16. 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

  17. The Whole-Brain "Global" Signal from Resting State fMRI as a Potential Biomarker of Quantitative State Changes in Glucose Metabolism.

    Science.gov (United States)

    Thompson, Garth J; Riedl, Valentin; Grimmer, Timo; Drzezga, Alexander; Herman, Peter; Hyder, Fahmeed

    2016-07-01

    The evolution of functional magnetic resonance imaging to resting state (R-fMRI) allows measurement of changes in brain networks attributed to state changes, such as in neuropsychiatric diseases versus healthy controls. Since these networks are observed by comparing normalized R-fMRI signals, it is difficult to determine the metabolic basis of such group differences. To investigate the metabolic basis of R-fMRI network differences within a normal range, eyes open versus eyes closed in healthy human subjects was used. R-fMRI was recorded simultaneously with fluoro-deoxyglucose positron emission tomography (FDG-PET). Higher baseline FDG was observed in the eyes open state. Variance-based metrics calculated from R-fMRI did not match the baseline shift in FDG. Functional connectivity density (FCD)-based metrics showed a shift similar to the baseline shift of FDG, however, this was lost if R-fMRI "nuisance signals" were regressed before FCD calculation. Average correlation with the mean R-fMRI signal across the whole brain, generally regarded as a "nuisance signal," also showed a shift similar to the baseline of FDG. Thus, despite lacking a baseline itself, changes in whole-brain correlation may reflect changes in baseline brain metabolism. Conversely, variance-based metrics may remain similar between states due to inherent region-to-region differences overwhelming the differences between normal physiological states. As most previous studies have excluded the spatial means of R-fMRI metrics from their analysis, this work presents the first evidence of a potential R-fMRI biomarker for baseline shifts in quantifiable metabolism between brain states. PMID:27029438

  18. Potential brain language reorganization in a boy with refractory epilepsy; an fNIRS–EEG and fMRI comparison

    OpenAIRE

    Phetsamone Vannasing; Isotta Cornaggia; Catherine Vanasse; Julie Tremblay; Paola Diadori; Sébastien Perreault; Maryse Lassonde; Anne Gallagher

    2016-01-01

    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 N...

  19. Neonatal brain MRI: how reliable is the radiologist's eye?

    International Nuclear Information System (INIS)

    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.)

  20. 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.)

  1. Brain MRI findings of welders : high signal intensity in T1WI secondary to manganese exposure

    International Nuclear Information System (INIS)

    To evaluate the clinical and brain MRI findings of welders and to determine the utility of MRI in the assessment of occupational manganese exposure. All welders complained of fatigue, headache, anorexia, and decreased libido. The palmomental reflex was positive in five (28%), Myerson's sign in four (22%), and intention tremor in three (17%). Mean blood Mn was 5.18 (range, 1.77-9.34) μg/dl, mean urine Mn was 5.84 (range, 1.07 -22) μg/l, serum Fe was elevated in one welder, and serum Cd in two. T1WI of brain MRI revealed high signal intensities in the globus pallidus, the putamen, the substantia nigra, the tectum, the caudate nucleus, the subthalamic nucleus, the hypothalamus and the pituitary gland. These intensities correlated closely with blood Mn levels, suggesting their potential role in estimating the accumulation of Mn in the brain. (author). 25 refs., 2 tabs., 5 figs

  2. Brain MRI findings of welders : high signal intensity in T1WI secondary to manganese exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. W.; Lim, M. A.; Shon, M. Y.; Lee, S. H.; Ha, D. G.; Kwon, K. R.; Kim, S. S.; Hong, Y. S.; Lee, Y. H. [Sunlin Presbyterian Hospital, Pohang (Korea, Republic of); Cheong, H. K. [Dongguk University, Seoul (Korea, Republic of)

    1998-03-01

    To evaluate the clinical and brain MRI findings of welders and to determine the utility of MRI in the assessment of occupational manganese exposure. All welders complained of fatigue, headache, anorexia, and decreased libido. The palmomental reflex was positive in five (28%), Myerson`s sign in four (22%), and intention tremor in three (17%). Mean blood Mn was 5.18 (range, 1.77-9.34) {mu}g/dl, mean urine Mn was 5.84 (range, 1.07 -22) {mu}g/l, serum Fe was elevated in one welder, and serum Cd in two. T1WI of brain MRI revealed high signal intensities in the globus pallidus, the putamen, the substantia nigra, the tectum, the caudate nucleus, the subthalamic nucleus, the hypothalamus and the pituitary gland. These intensities correlated closely with blood Mn levels, suggesting their potential role in estimating the accumulation of Mn in the brain. (author). 25 refs., 2 tabs., 5 figs.

  3. [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).

  4. 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.

  5. 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.

  6. The Safety of Using Body-Transmit MRI in Patients with Implanted Deep Brain Stimulation Devices

    OpenAIRE

    Joshua Kahan; Anastasia Papadaki; Mark White; Laura Mancini; Tarek Yousry; Ludvic Zrinzo; Patricia Limousin; Marwan Hariz; Tom Foltynie; John Thornton

    2015-01-01

    Background Deep brain stimulation (DBS) is an established treatment for patients with movement disorders. Patients receiving chronic DBS provide a unique opportunity to explore the underlying mechanisms of DBS using functional MRI. It has been shown that the main safety concern with MRI in these patients is heating at the electrode tips – which can be minimised with strict adherence to a supervised acquisition protocol using a head-transmit/receive coil at 1.5T. MRI using the body-transmit co...

  7. 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.

  8. 我国正常成人脑灰质的MRI及1H MRS定量研究%Quantitative Study of MRI and 1H MRS in Normal Adult Brain

    Institute of Scientific and Technical Information of China (English)

    范国光; 吴振华; 张伟; 段阳; 潘诗农; 郭启勇

    2001-01-01

    Objective:To evaluate magnetic resonance imaging(MRI) and 1Hmagnetic resonance spectroscopy(1H MRS)in the study of normal biochemical process of the brain as well as differentiation of normal senile brain from cerebral diseases related to senility.Methods:180 cases of healthy adults were selected to perform MR examination,in which,none of the subjects had the history of neurological and psychotic diseases according to MRI and clinical results.Meanwhile,60 healthy subjects were selected to perform 1H MRS examination.The ages ranged from 18 to 80 years.They were divided into six age groups purposely.Point resolved spectroscopy sequence was required for 1H MRS.The metabolites in the spectra included:N-acetylaspartate(NAA),choline compounds(CHO),creatine compounds(CR),myo-inosito(MI),glutamate and glutamine(Glu-n).Results:(1)In 180 cases of MRI,T2 relation time was lowest in the deep gray matter in the same age group;T1 relation time was in low-high order,while T2 relation time was decreased with the increase of age in the different age group.(2)The amplitudes in high-to-low order were as follows in 60 cases of 1H MRS:NAA、CR、CHO、MI、Glu-n.No prominent difference of shape and peak arrangement was seen at the different ipsilateral site in the same age groups;while slight difference at the same site in the different age groups was present.The ratio of NAA/Cr and Glu-n CR was higher in senile age group;while that of MI/Cr was lower.The ratio of CHO/CR was in low-to high order with the difference of age.The ratio of NAA/CR and MI/CR was gradually lower from anterior to posterior part of the brain;the ratio of CHO/CR was highest in occipital cortex however,no definite changing rule was observed in the ration of Glu-n/CR.Correlation of T1 relation time and partial metabolite ratio with age was present in gray matter.Conclusion:Quantitative study of MRI and 1H MRS is essential for determination of normal myelinization and neuronal integrity and age

  9. 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 i