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White Matter Volumes (white + matter_volume)
Selected AbstractsA novel ARX phenotype: rapid neurodegeneration with Ohtahara syndrome and a dyskinetic movement disorderDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2010MICHAEL ABSOUD ARX mutations are associated with variable clinical phenotypes. We report a new neurodegenerative phenotype associated with a known ARX mutation and causing early abnormal neurodevelopment, a complex movement disorder, and early infantile epileptic encephalopathy with a suppression-burst pattern (Ohtahara syndrome). A male infant presented at age 5 months with a dyskinetic movement disorder, which was initially diagnosed as infantile spasms. Clinical deterioration was accompanied by progressive cortical atrophy with a reduction in white matter volume and resulting in death in the first year of life; such a rapidly progressive and severe phenotype has not previously been described. ARX mutation testing should be undertaken in children aged less than 1 year with Ohtahara syndrome and a movement disorder, and in infants with unexplained neurodegeneration, progressive white matter loss, and cortical atrophy. [source] Chronic effects of low to moderate alcohol consumption on structural and functional properties of the brain: beneficial or not?,HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2009Marinus N. Verbaten Abstract Objective Some studies suggest that the effects of low to moderate drinking (about 1,3 standard glasses of alcohol per day) on the brain and cognitive performance are positive. In the present study this hypothesis is investigated. Methods For this purpose studies on the effects of low to moderate drinking on brain structure (Magnetic Resonance Induction (MRI) studies) and on cognitive performance were analysed and discussed Results In MRI studies, a linear negative effect of alcohol consumption on brain volume was found. Furthermore, a linear decrease in grey matter concurring with a linear increase in white matter volumes as a function of number of drinks was reported in males, but not in females. Only in elderly low to moderate drinkers (aged,>,65 years) there appeared to be an U-shaped relationship between alcohol consumption and white matter integrity (grade) on the one hand and cognition on the other hand. Conclusions The changes reported in brain shrinkage, grey matter and white matter volume, as a result of low to moderate alcohol consumption sooner offer support for the contention that such drinking decreases brain health than for its beneficial effect. An exception might hold for elderly light and moderate drinkers where less white matter damage was found than in abstainers concurring with better cognitive performance. However, methodological problems impose limits on this conclusion. Copyright © 2009 John Wiley & Sons, Ltd. [source] Coronary heart disease is associated with regional grey matter volume loss: implications for cognitive function and behaviourINTERNAL MEDICINE JOURNAL, Issue 7 2008O. P. Almeida Abstract Coronary heart disease (CHD) has been associated with impaired cognition, but the mechanisms underlying these changes remain unclear. We designed this study to determine whether adults with CHD show regional brain losses of grey matter volume relative to controls. We used statistical parametric mapping (SPM5) to determine regional changes in grey matter volume of T1 -weighted magnetic resonance images of 11 adults with prior history of myocardial infarction relative to seven healthy controls. All analyses were adjusted for total grey and white matter volume, age, sex and handedness. CHD participants showed a loss of grey matter volume in the left medial frontal lobe (including the cingulate), precentral and postcentral cortex, right temporal lobe and left middle temporal gyrus, and left precuneus and posterior cingulate. CHD is associated with loss of grey matter in various brain regions, including some that play a significant role in cognitive function and behaviour. The underlying causes of these regional brain changes remain to be determined. [source] Voxel-Based Morphometry and Voxel-Based Relaxometry in Parkinsonian Variant of Multiple System AtrophyJOURNAL OF NEUROIMAGING, Issue 3 2010Loukia C. Tzarouchi MD ABSTRACT BACKGROUND AND PURPOSE Multiple system atrophy (MSA) is a progressive neurodegenerative disorder divided into a parkinsonian (MSA-P) and a cerebellar variant. The purpose of this study was to assess regional brain atrophy and iron content using Voxel-based morphometry (VBM) and Voxel-based relaxometry (VBR) respectively, in MSA-P. METHODS Using biological parametric mapping the effect of brain atrophy was evaluated in T2 relaxation time (T2) measurements by applying analysis of covariance (ANCOVA) and correlation analysis to the VBM and VBR data. Eleven patients with MSA-P (aged 61.9 ± 11.7 years, disease duration 5.42 ± 2.5 years) and 11 controls were studied. RESULTS In comparison to the controls the patients showed decreased gray matter in the putamen, the caudate nuclei, the thalami, the anterior cerebellar lobes, and the cerebral cortex, and white matter atrophy in the pons, midbrain, and peduncles. VBR analysis showed prolonged T2 in various cortical regions. On ANCOVA, when controlling for gray and white matter volume, these regions of prolonged T2 were shrunk. Negative correlation was demonstrated between T2 and gray and white matter volume. CONCLUSIONS Diffuse brain atrophy, mainly in the motor circuitry is observed in MSA-P. Normalization for atrophy should always be performed in T2 measurements. [source] Reduced gray matter volume of dorsal cingulate cortex in patients with obsessive,compulsive disorder: A voxel-based morphometric studyPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2010Ryohei Matsumoto MD Aims:, Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive,compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel-based morphometry (VBM) method. Methods:, Sixteen patients with OCD free of comorbid major depression, and 32 sex- and age-matched healthy subjects underwent MRI using a 1.5-T MR scanner. OCD severity was assessed with the Yale,Brown Obsessive,Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7,32). MR images were spatially normalized and segmented using the VBM5 package (http://dbm.neuro.uni-jena.de/vbm/). Statistical analysis was performed using statistical parametric mapping software. Results:, Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P < 0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale,Brown Obsessive,Compulsive Scale score and regional gray matter or white matter volume was observed. Conclusions:, Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non-emotional cognitive processes, may be related to the pathophysiology in OCD. [source] Brain dysmorphology in individuals with severe prenatal alcohol exposureDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2001Sarah L Archibald MA Our previous studies revealed abnormalities on structural MRI (sMRI) in small groups of children exposed to alcohol prenatally. Microcephaly, disproportionately reduced basal ganglia volume, and abnormalities of the cerebellar vermis and corpus callosum were demonstrated. The present study used sMRI to examine in detail the regional pattern of brain hypoplasia resulting from prenatal exposure to alcohol using a higher resolution imaging protocol and larger sample sizes than reported previously. Fourteen participants (mean 11.4 years; eight females, six males) with fetal alcohol syndrome (FAS) and 12 participants (mean 14.8 years; four females, eight males) with prenatal exposure to alcohol (PEA) but without the facial features of FAS were compared to a group of 41 control participants (mean 12.8 years, 20 females, 21 males). Findings of significant microcephaly and disproportionately reduced basal ganglia volumes in the FAS group were confirmed. Novel findings were that in FAS participants, white matter volumes were more affected than gray matter volumes in the cerebrum, and parietal lobes were more affected than temporal and occipital lobes. Among subcortical structures, in contrast to the disproportionate effects on caudate nucleus, the hippocampus was relatively preserved in FAS participants. Differences between the PEA group and controls were generally non-significant; however, among a few of the structures most affected in FAS participants, there was some evidence for volume reduction in PEA participants as well, specifically in basal ganglia and the parietal lobe. There were no group differences in cerebral volume asymmetries. Severe prenatal alcohol exposure appears to produce a specific pattern of brain hypoplasia. [source] No change in the structure of the brain in migraine: a voxel-based morphometric studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2003M. S. Matharu Migraine is a common, disabling form of primary neurovascular headache. For most of the twentieth century it was regarded as a vascular headache whose primary pathophysiology lay in the cranial vasculature. Functional brain imaging using positron emission tomography has demonstrated activation of the rostral brain stem in acute migraine. Voxel-based morphometry is a new fully automated whole brain technique that is sensitive to subtle macroscopic and mesoscopic structural differences between groups of subjects. In this study 11 patients suffering from migraine with aura (10 females, one male: 23,52 years, mean 31); 11 controls (10 females, one male: 23,52, mean 31); 17 patients with migraine without aura (16 females, one male: 24,57, mean 34); 17 controls (16 females, one male: 24,57, mean 34) were imaged with high resolution volumetric magnetic resonance imaging. There was no significant difference in global grey or white matter volumes between either patients with migraine and controls, or patients with aura and without aura. This study did not show any global or regional macroscopic structural difference between patients with migraine and controls, with migraine sufferers taken as homogenous groups. If structural changes are to be found, other methods of phenotyping migraine, such as by genotype or perhaps treatment response, may be required to resolve completely whether there is some subtle structural change in the brain of patients with migraine. [source] Heritability of regional and global brain structure at the onset of puberty: A magnetic resonance imaging study in 9-year-old twin pairsHUMAN BRAIN MAPPING, Issue 7 2009Jiska S. Peper Abstract Puberty represents the phase of sexual maturity, signaling the change from childhood into adulthood. During childhood and adolescence, prominent changes take place in the brain. Recently, variation in frontal, temporal, and parietal areas was found to be under varying genetic control between 5 and 19 years of age. However, at the onset of puberty, the extent to which variation in brain structures is influenced by genetic factors (heritability) is not known. Moreover, whether a direct link between human pubertal development and brain structure exists has not been studied. Here, we studied the heritability of brain structures at 9 years of age in 107 monozygotic and dizygotic twin pairs (N = 210 individuals) using volumetric MRI and voxel-based morphometry. Children showing the first signs of secondary sexual characteristics (N = 47 individuals) were compared with children without these signs, based on Tanner-stages. High heritabilities of intracranial, total brain, cerebellum, and gray and white matter volumes (up to 91%) were found. Regionally, the posterior fronto-occipital, corpus callosum, and superior longitudinal fascicles (up to 93%), and the amygdala, superior frontal and middle temporal cortices (up to 83%) were significantly heritable. The onset of secondary sexual characteristics of puberty was associated with decreased frontal and parietal gray matter densities. Thus, in 9-year-old children, global brain volumes, white matter density in fronto-occipital and superior longitudinal fascicles, and gray matter density of (pre-)frontal and temporal areas are highly heritable. Pubertal development may be directly involved in the decreases in gray matter areas that accompany the transition of our brains from childhood into adulthood. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] Evaluation of automated brain MR image segmentation and volumetry methodsHUMAN BRAIN MAPPING, Issue 4 2009Frederick Klauschen Abstract We compare three widely used brain volumetry methods available in the software packages FSL, SPM5, and FreeSurfer and evaluate their performance using simulated and real MR brain data sets. We analyze the accuracy of gray and white matter volume measurements and their robustness against changes of image quality using the BrainWeb MRI database. These images are based on "gold-standard" reference brain templates. This allows us to assess between- (same data set, different method) and also within-segmenter (same method, variation of image quality) comparability, for both of which we find pronounced variations in segmentation results for gray and white matter volumes. The calculated volumes deviate up to >10% from the reference values for gray and white matter depending on method and image quality. Sensitivity is best for SPM5, volumetric accuracy for gray and white matter was similar in SPM5 and FSL and better than in FreeSurfer. FSL showed the highest stability for white (<5%), FreeSurfer (6.2%) for gray matter for constant image quality BrainWeb data. Between-segmenter comparisons show discrepancies of up to >20% for the simulated data and 24% on average for the real data sets, whereas within-method performance analysis uncovered volume differences of up to >15%. Since the discrepancies between results reach the same order of magnitude as volume changes observed in disease, these effects limit the usability of the segmentation methods for following volume changes in individual patients over time and should be taken into account during the planning and analysis of brain volume studies. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [source] Chronic effects of low to moderate alcohol consumption on structural and functional properties of the brain: beneficial or not?,HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2009Marinus N. Verbaten Abstract Objective Some studies suggest that the effects of low to moderate drinking (about 1,3 standard glasses of alcohol per day) on the brain and cognitive performance are positive. In the present study this hypothesis is investigated. Methods For this purpose studies on the effects of low to moderate drinking on brain structure (Magnetic Resonance Induction (MRI) studies) and on cognitive performance were analysed and discussed Results In MRI studies, a linear negative effect of alcohol consumption on brain volume was found. Furthermore, a linear decrease in grey matter concurring with a linear increase in white matter volumes as a function of number of drinks was reported in males, but not in females. Only in elderly low to moderate drinkers (aged,>,65 years) there appeared to be an U-shaped relationship between alcohol consumption and white matter integrity (grade) on the one hand and cognition on the other hand. Conclusions The changes reported in brain shrinkage, grey matter and white matter volume, as a result of low to moderate alcohol consumption sooner offer support for the contention that such drinking decreases brain health than for its beneficial effect. An exception might hold for elderly light and moderate drinkers where less white matter damage was found than in abstainers concurring with better cognitive performance. However, methodological problems impose limits on this conclusion. Copyright © 2009 John Wiley & Sons, Ltd. [source] The functional neuroanatomy of geriatric depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2009Gwenn S. Smith Abstract Objective Positron Emission Tomography (PET) studies of cerebral glucose metabolism have demonstrated sensitivity in evaluating the functional neuroanatomy of treatment response variability in depression, as well as in the early detection of functional changes associated with incipient cognitive decline. The evaluation of cerebral glucose metabolism in late life depression may have implications for understanding treatment response variability, as well as evaluating the neurobiological basis of depression in late life as a risk factor for dementia. Methods Sixteen patients with geriatric depression and 13 comparison subjects underwent resting PET studies of cerebral glucose metabolism, as well as magnetic resonance (MR) imaging scans to evaluate brain structure. Results Cerebral glucose metabolism was elevated in geriatric depressed patients relative to comparison subjects in anterior (right and left superior frontal gyrus) and posterior (precuneus, inferior parietal lobule) cortical regions. Cerebral atrophy (increased cerebrospinal fluid [CSF] and decreased grey and white matter volumes) were observed in some of these regions, as well. Regional cerebral metabolism was positively correlated with severity of depression and anxiety symptoms. Conclusions In contrast to decreased metabolism observed in normal aging and neurodegenerative conditions such as Alzheimer's disease, cortical glucose metabolism was increased in geriatric depressed patients relative to demographically matched controls, particularly in brain regions in which cerebral atrophy was observed, which may represent a compensatory response. Copyright © 2009 John Wiley & Sons, Ltd. [source] In vivo quantitative proton MRSI study of brain development from childhood to adolescence,JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2002Alena Horská PhD Abstract Purpose To quantify regional variations in metabolite levels in the developing brain using quantitative proton MR spectroscopic imaging (MRSI). Materials and Methods Fifteen healthy subjects three to 19 years old were examined by in vivo multislice proton MRSI. Concentrations of N-acetyl aspartate (NAA), total choline (Cho), total creatine (Cr), and peak area ratios were determined in selected frontal and parietal gray and white matter regions, basal ganglia, and thalamus. Results In cortical gray matter regions, the ratio of NAA/Cho increased to a maximum at 10 years and decreased thereafter (P = 0.010). In contrast, in white matter, average ratios NAA/Cho increased linearly with age (P = 0.045). In individual brain regions, age-related changes in NAA/Cho were found in the putamen (P = 0.044). No significant age-related changes in NAA, Cho, Cr, or other metabolite ratios could be determined. Conclusion Consistent with recent studies using other structural and functional neuroimaging techniques, our data suggest that small but significant changes occur in regional cerebral metabolism during childhood and adolescence. Non-linear age related changes of NAA/Cho in frontal and parietal areas, resembling previously reported age related changes in rates of glucose utilization and cortical volumes, may be associated with dendritic and synaptic development and regression. Linear age-related changes of NAA/Cho in white matter are also in agreement with age-related increases in white matter volumes, and may reflect progressive increases in axonal diameter and myelination. J. Magn. Reson. Imaging 2002;15:137,143. Published 2002 Wiley-Liss, Inc. [source] Reduced gray matter volume of dorsal cingulate cortex in patients with obsessive,compulsive disorder: A voxel-based morphometric studyPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2010Ryohei Matsumoto MD Aims:, Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive,compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel-based morphometry (VBM) method. Methods:, Sixteen patients with OCD free of comorbid major depression, and 32 sex- and age-matched healthy subjects underwent MRI using a 1.5-T MR scanner. OCD severity was assessed with the Yale,Brown Obsessive,Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7,32). MR images were spatially normalized and segmented using the VBM5 package (http://dbm.neuro.uni-jena.de/vbm/). Statistical analysis was performed using statistical parametric mapping software. Results:, Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P < 0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale,Brown Obsessive,Compulsive Scale score and regional gray matter or white matter volume was observed. Conclusions:, Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non-emotional cognitive processes, may be related to the pathophysiology in OCD. [source] Gray matter, white matter, brain, and intracranial volumes in first-episode bipolar disorder: a meta-analysis of magnetic resonance imaging studiesBIPOLAR DISORDERS, Issue 8 2009Antonio Vita Objectives:, To perform a comprehensive quantitative analysis of the existing magnetic resonance imaging (MRI) studies of the brain conducted on patients with first-episode bipolar disorder (BD). Methods:, A systematic search was performed of MRI studies that reported quantitative measurements of brain volumes of first-episode bipolar patients and healthy controls. Four meta-analyses were performed for four cerebral regions. Results:, Significant overall effect sizes were demonstrated, with a reduction detected in patients with BD for total intracranial and white matter volumes, but not for gray matter and whole brain volumes. Conclusions:, The available MRI literature indicates that specific structural brain abnormalities are already present in first-episode bipolar patients. These do not overlap with those emerging from previous meta-analyses performed in patients with chronic BD. These findings support the hypothesis of different patterns of changes in brain morphology over the time course of bipolar disorder. [source] | ||||||||||||||||||||||