Home About us Contact
|
Home About us Contact | ||
|
|
||
Magnetic Resonance Imaging Brain (magnetic + resonance_imaging_brain)
Selected AbstractsEffects of brain-derived neurotrophic factor Val66Met polymorphism on hippocampal volume change in schizophreniaHIPPOCAMPUS, Issue 9 2010P. Cédric M.P. Koolschijn Abstract A functional polymorphism of the brain-derived neurotrophic factor (BDNF) gene (Val66Met) has been associated with the risk for schizophrenia and volume differences in the hippocampus. However, little is known about the association between progressive brain volume change in schizophrenia and BDNF genotype. The aim of this study was to investigate the relationship between hippocampal volume change in patients with schizophrenia and healthy control subjects and BDNF genotype. Two structural magnetic resonance imaging brain scans were acquired of 68 patients with schizophrenia and 83 healthy subjects with an interval of approximately 5 yrs. Hippocampal volume change was measured and related to BDNF genotype in patients and healthy controls. BDNF genotype was not associated with hippocampal volume change over time in patients or healthy controls, nor could we replicate earlier findings on smaller hippocampal volume in Met-carriers. However, we did find a genotype-by-diagnosis interaction at baseline demonstrating smaller hippocampal volumes in patients homozygous for the Val-allele relative to healthy Val-homozygotes. In addition, irrespective of genotype, patients showed smaller hippocampal volumes compared with healthy controls at baseline. In summary, our results suggest that the BDNF Val66Met polymorphism is not associated with hippocampal volume change over time. Nevertheless, our findings may support the possibility that BDNF affects brain morphology differently in schizophrenia patients and healthy subjects. © 2009 Wiley-Liss, Inc. [source] Functional and Cognitive Consequences of Silent Stroke Discovered Using Brain Magnetic Resonance Imaging in an Elderly PopulationJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 7 2004Wolf-Peter Schmidt MD Objectives: To evaluate the prevalence of silent stroke and its associated consequences on physical, cognitive, and emotional functioning in an elderly population. Design: Population-based cross-sectional survey. Setting: The Memory and Morbidity in Augsburg Elderly project in the Augsburg region of southern Germany. Participants: Two hundred sixty-seven community-dwelling persons aged 65 to 83. Measurements: The presence of silent stroke was determined using magnetic resonance imaging brain scan and a single question asking for physician-diagnosed stroke in each participant. The health effect of silent stroke was assessed using rating scales for self-perceived health status (36-item short-form health survey), activities of daily living (ADLs) and instrumental ADLs, cognitive function, and depression (Center for Epidemiologic Studies Depression scale). Results: Just fewer than 13% (12.7%) of participants were affected by silent stroke. Silent stroke was associated with a history of hypertension, heart surgery, and elevated C-reactive protein. Individuals with silent stroke showed impairments on the Mini-Mental State Examination test and in the cognitive domains of memory, procedural speed, and motor performance. Conclusion: The presence of silent stroke has a considerable effect on cognitive performance in those affected. Determining the presence of silent stroke using brain imaging may contribute to identifying individuals at risk for developing gradual neurological deficits. [source] Brain involvement in muscular dystrophies with defective dystroglycan glycosylation,ANNALS OF NEUROLOGY, Issue 5 2008Emma Clement MBChB Objective To assess the range and severity of brain involvement, as assessed by magnetic resonance imaging, in 27 patients with mutations in POMT1 (4), POMT2 (9), POMGnT1 (7), Fukutin (4), or LARGE (3), responsible for muscular dystrophies with abnormal glycosylation of dystroglycan (dystroglycanopathies). Methods Blinded review of magnetic resonance imaging brain scans from 27 patients with mutations in 1 of these 5 genes. Results Brain magnetic resonance images were normal in 3 of 27 patients; in another 5, only nonspecific abnormalities (ventricular dilatation, periventricular white matter abnormalities, or both) were seen. The remaining 19 patients had a spectrum of structural defects, ranging from complete lissencephaly in patients with Walker,Warburg syndrome to isolated cerebellar involvement. Cerebellar cysts and/or dysplasia and hypoplasia were the predominant features in four patients. Polymicrogyria (11/27) was more severe in the frontoparietal regions in 6, and had an occipitofrontal gradient in 2. Pontine clefts, with an unusual appearance to the corticospinal tracts, were seen in five patients with a muscle-eye-brain,like phenotype, three patients with POMGnT1, one with LARGE, and one with POMT2 mutations. Prominent cerebellar cysts were always seen with POMGnT1 mutations, but rarely seen in POMT1 and POMT2. Brainstem and pontine abnormalities were common in patients with POMT2, POMGnT1, and LARGE mutations. Interpretation Our results expand the spectrum of brain involvement associated with mutations in LARGE, POMGnT1, POMT1, and POMT2. Pontine clefts were visible in some dystroglycanopathy patients. Infratentorial structures were often affected in isolation, highlighting their susceptibility to involvement in these conditions. Ann Neurol 2008;64:573,582 [source] Structural abnormalities of ventrolateral and orbitofrontal cortex in patients with familial bipolar disorderBIPOLAR DISORDERS, Issue 2 2009Andrew C Stanfield Objectives:, Abnormalities of ventral prefrontal function have been widely reported in bipolar disorder, but reports of structural abnormalities in the same region are less consistent. We examined the presence and location of ventral prefrontal abnormalities in a large sample of individuals with bipolar disorder and their relationship to gender, psychotic symptoms, and age. Methods:, Structural magnetic resonance imaging brain scans were carried out on 66 individuals with bipolar disorder, type I, and 66 controls. Voxel-based morphometry was used to examine differences in grey and white matter density between the groups and their relationship with a lifetime occurrence of psychotic symptoms and age. Results:, Reductions in grey matter density were seen in the left and right lateral orbital gyri and the right inferior frontal gyrus, while white matter density reductions were seen in the corona radiata and the left temporal stem. In contrast, hallucinations and positive symptoms were associated with grey matter reduction in the left middle temporal gyrus. Age was more strongly associated with the right inferior frontal gyrus grey matter reductions in the bipolar group than in the controls, but not with any other finding. Conclusion:, Abnormalities of the ventral prefrontal cortex are likely to be involved in the aetiopathology of bipolar disorder, while hallucinations appear to be more closely associated with temporal lobe abnormality, extending earlier work in schizophrenia. Further prospective studies are required to comprehensively address the trajectory of these findings. [source] | ||||||||||