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White Matter Changes (white + matter_change)
Selected AbstractsWhite matter changes in Leber's hereditary optic neuropathy: MRI findingsEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2007W. Küker Leber's hereditary optic neuropathy is a mitochondrial disorder causing bilateral optic nerve degeneration. It is sometimes associated with clinical signs of multiple sclerosis. We report MRI findings in two patients with LHON-MS and comment on possible distinguishing features of this disease entity. [source] Combination of T2*W and FLAIR Abnormalities for the Prediction of Parenchymal Hematoma Following Thrombolytic Therapy in 100 Stroke PatientsJOURNAL OF NEUROIMAGING, Issue 4 2009Jens Fiehler MD ABSTRACT INTRODUCTION The objective of our study was to determine whether the combination of hypointense spots ("cerebral microbleeds," CMBs) with a leukoaraiosis is associated with the risk of parenchymal hematoma (PH) after thrombolytic therapy. PATIENTS AND METHODS We analyzed magnetic resonance imaging (MRI) scans acquired within 6 hours after symptom onset from 100 ischemic stroke patients. Multiparametric MRI including a T2*-weighted (T2*w) MRI and fluid attenuated inversion recovery (FLAIR) was performed before thrombolysis in all patients. Initial T2*w imaging was rated by two independent observers for the presence of CMBs smaller than 5 mm. White matter changes were evaluated using an adapted scale of Fazekas and Schmidt. PH was defined in follow-up imaging. FINDINGS A PH was observed in seven per 100 patients. CMBs were detected by observer 1 in 22 and observer 2 in 20 patients. We found a very low sensitivity (0.14) for prediction of PH by the presence of CMBs. We found a concordant increase in the rate of PH when the periventricular hyperintensity in FLAIR was larger than a thin lining. Sensitivity was good-to-perfect (0.86 and 1.00, observers 1 and 2) and specificity was substantial (0.65 and 0.66). Using the combination of a periventricular matter lesion (PVML)>1 and the presence of CMBs did not improve the prediction of PH. DISCUSSION A marked periventricular hyperintensity in FLAIR imaging seems to be associated with a substantially increased risk of PH. A combination of CMBs with leukoaraiosis scores did not appear to be beneficial for prognosis. [source] White matter changes in normal pressure hydrocephalus and Binswanger disease: specificity, predictive value and correlations to axonal degeneration and demyelinationACTA NEUROLOGICA SCANDINAVICA, Issue 6 2002M. Tullberg Objectives, To analyse the diagnostic and prognostic value of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) magnetic resonance imaging (MRI) changes and their relation to symptoms and cerebrospinal fluid (CSF) markers of demyelination (sulphatide) and axonal degeneration [neurofilament triplet protein (NFL)] in a large series of patients with normal pressure hydrocephalus (NPH) and Binswanger disease (BD). Materials and methods, PVH and DWMH were determined by a semi-automatic segmentation method on T2-weighted images in 29 patients with NPH and 17 patients with BD. CSF analyses, psychometric testing and quantification of balance, gait and continence were performed in all patients and also postoperatively in NPH patients. Results, No MRI variable could identify NPH or BD patients. Abundant PVH and DWMH preoperatively correlated with improvement in gait, balance and psychometric performance after shunt surgery (P < 0.05). CSF sulphatide correlated positively with the amount of DWMH (P < 0.05) while NFL was correlated to both PVH and DWMH (P < 0.05). Abundant PVH correlated with poor psychometric performance while DWMH correlated with gait disturbance (P < 0.05). Postoperative reduction in PVH correlated with improvement in gait, balance and psychometric performance. Conclusion, In spite of a refined quantification method, NPH and BD patients exhibited similar MRI changes. MRI had a predictive value in NPH patients. DWMH might relate to demyelination and PVH to neuronal axonal dysfunction. NPH and BD share the major part of symptoms and MRI changes, indicating a common pathophysiological pattern, and we raise the question of how to treat BD patients. [source] White matter changes in extremely preterm infants, a population-based diffusion tensor imaging studyACTA PAEDIATRICA, Issue 6 2010Béatrice Skiöld Abstract Aim:, To investigate cerebral white matter (WM) abnormalities (J Pediatr 2003; 143: 171) and diffuse and excessive high signal intensities (DEHSI), (J Pediatr 1999; 135: 351) in a cohort of extremely preterm infants born in Stockholm during a 3-year period, using magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Methods:, MRI at term-equivalent age was performed in 109 infants and DTI data were acquired in 54 infants. Survival rate in the entire cohort was 67%. Sixteen term-born healthy control infants were scanned for comparison. Results:, No or mild WM abnormalities were seen in 86% of infants and 14% had moderate or severe WM abnormalities. DEHSI were seen in infants with all grades of white matter abnormalities and were present in 56% of infants. In the WM at the level of centrum semiovale, infants with any WM abnormalities or DEHSI had lower Fractional Anisotropy and higher Apparent Diffusion Coefficient compared with control infants. No significant differences in diffusion were seen in infants without DEHSI compared with the controls in this region. Compared with controls, the preterm infants had significantly altered diffusion in the corpus callosum. Conclusion:, Only 14% of the extremely preterm infants had moderate or severe WM abnormalities on MRI. However, the incidence of DEHSI was high. In the DEHSI regions, changes in diffusion parameters were detected, indicating altered WM organization. [source] Diffusion-tensor MR imaging for evaluation of the efficacy of hyperbaric oxygen therapy in patients with delayed neuropsychiatric syndrome caused by carbon monoxide inhalationEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2007C.-P. Lo The purpose of this study is to assess the efficacy of hyperbaric oxygen therapy (HBOT) in patients with delayed neuropsychiatric syndrome (DNS) caused by carbon monoxide (CO) inhalation using diffusion tensor magnetic resonance (MR) imaging and neuropsychological test. Conventional and diffusion tensor brain MR imaging exams were performed in six patients with DNS immediately before and 3 months after the HBOT to obtain fractional anisotropy (FA) values. Six age- and sex-matched normal control subjects also received MR exams for comparison. Mini-Mental State Examination (MMSE) was also performed in patients immediately before and 3 months after the HBOT. A significantly higher mean FA value was found in control subjects as compared with the patients both before and 3 months after the HBOT (P < 0.001). The mean FA value 3 months after the HBOT was also significantly higher than that before the HBOT in the patient group (P < 0.001). All of the patients regained full scores in the MMSE 3 months after the HBOT. Diffusion tensor MR imaging can be a quantitative method for the assessment of the white matter change and monitor the treatment response in patients of CO-induced DNS with a good clinical correlation. HBO may be an effective therapy for DNS. [source] Hypertension, white matter change and response to cholinesterase inhibitors in Alzheimer's diseaseINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2005Peter J. Connelly Abstract Background Cholinesterase inhibitors are used to treat mild to moderate Alzheimer's disease. Their role in patients with concurrent cerebrovascular disease has been less well studied, and the influence of vascular risk factors on response to treatment is uncertain. We investigated the effect of hypertension and white matter lesions (WML) on response. Methods A retrospective sample of 160 consecutive out-patients who had blood pressure measured and the presence or absence of WML recorded at baseline and who completed six months treatment with a cholinesterase inhibitor was studied. Subjects scored either zero or one on the Modified Hachinski Ischaemic Scale. Subjects were assessed using the Mini-Mental State Examination (MMSE), the Digit Symbol Substitution test (DSST) and both the Instrumental Activities of Daily Living (IADL) and Social Behaviour (SB) sub-scales of the Nurses Observation Scale for Geriatric Patients (NOSGER). Results 43.9% of the total study population were classified as good responders using our criteria. Neither the presence of hypertension nor the presence of WML alone influenced outcome. However, there was a statistically significant interaction between blood pressure and WML on outcome variables on multiple analysis of variance (MANOVA) (F(4,,139),=,5.60, p,<,0.0005). Subjects with both hypertension and WML deteriorate to a significantly greater extent in IADL and SB scores than any other group (p,<,0.05 in each case). This effect could not be explained by age or by smoking status. Conclusion Our results support the hypothesis that there is an interaction between hypertension and WML that adversely influences functional change during cholinesterase inhibitor treatment. Our results are a contrast to suggestions that subjects with vascular disease show a better response to cholinesterase inhibitors. We recommend careful exploration of factors that may influence outcome. Copyright © 2005 John Wiley & Sons, Ltd. [source] Executive functioning in Alzheimer's disease and vascular dementia,INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 6 2010B. McGuinness Abstract Objective To compare performance of patients with mild-moderate Alzheimer's disease (AD) and vascular dementia (VaD) on tests of executive functioning and working memory. Methods Patients with AD (n,=,76) and VaD (n,=,46) were recruited from a memory clinic along with dementia free participants (n,=,28). They underwent specific tests of working memory from the Cognitive Drug Research (CDR) battery and pen and paper tests of executive function including CLOX 1 & 2, EXIT25 and a test of verbal fluency (COWAT). All patients had a CT brain scan which was independently scored for white matter change/ischaemia. Results The AD and VaD groups were significantly impaired on all measures of working memory and executive functioning compared to the disease free group. There were no significant differences between the AD and VaD groups on any measure. Z- scores confirmed the pattern of impairment in executive functioning and working memory was largely equivalent in both patient groups. Small to moderate correlations were seen between the MMSE and the neurocognitive scores in both patient groups and the pattern of correlations was also very similar in both patient groups. Conclusions This study demonstrates sizeable executive functioning and working memory impairments in patients with mild-moderate AD and VaD but no significant differences between the disease groups. Copyright © 2009 John Wiley & Sons, Ltd. [source] Widespread axonal damage in the brain of drug abusers as evidenced by accumulation of ,-amyloid precursor protein (,-APP): an immunohistochemical investigationADDICTION, Issue 9 2006Andreas Büttner ABSTRACT Background In drug abusers, white matter changes have been described by neuroimaging analyses in different brain regions. A specific pattern of involvement or a predominance of a specific brain region could not be drawn. Aims To examine alterations of the white matter as a possible morphological substrate of the neuroimaging findings. Methods Brain specimens of 30 polydrug abusers and 20 controls were obtained at autopsy. The white matter from 11 different brain regions was analysed by means of immunohistochemistry for ,-amyloid precursor protein (,-APP), a marker of axonal damage. Findings In the white matter of polydrug abusers, ,-APP-immunopositive accumulations were increased significantly compared to controls. They were more prominent in the brains of younger drug abusers than in those of the elderly. With the exception of five cases (four polydrug abusers and one control case), there were no significant white matter changes seen on myelin-stained sections, but there was a concomitant microglial activation. Conclusions Our results show a significant axonal damage in the brains of polydrug abusers, which might represent the morphological substrate of a chronic-progressive drug-induced toxic-metabolic process. It is yet to be established if the observed changes are responsible for the alterations seen in different neuroimaging analyses and which drugs of abuse might be of major pathogenetic significance. [source] Cerebral grey and white matter changes in mild cognitive impairment and Alzheimer's diseaseEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2009C. Luckhaus No abstract is available for this article. [source] MRI of late microstructural and metabolic alterations in radiation-induced brain injuriesJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2009Kevin C. Chan BEng Abstract Purpose To evaluate the late effects of radiation-induced damages in the rat brain by means of in vivo multiparametric MRI. Materials and Methods The right hemibrains of seven Sprague-Dawley rats were irradiated with a highly collimated 6 MV photon beam at a single dose of approximately 28 Gy. Diffusion tensor imaging (DTI), proton MR spectroscopy (1H-MRS), T2-weighted imaging, and T1-weighted imaging were performed to the same animals 12 months after radiation treatment. Results Compared with the contralateral side, a significantly higher percentage decrease in fractional anisotropy was observed in the ipsilateral fimbria of hippocampus (29%) than the external capsule (8%) in DTI, indicating the selective vulnerability of fimbria to radiation treatment. Furthermore, in 1H-MRS, significantly higher choline, glutamate, lactate, and taurine peaks by 24%, 25%, 87%, and 58%, respectively, were observed relative to creatine in the ipsilateral brain. Postmortem histology confirmed these white matter degradations as well as glial fibrillary acidic protein and glutamine synthetase immunoreactivity increase in the ipsilateral brain. Conclusion The microstructural and metabolic changes in late radiation-induced brain injuries were documented in vivo. These multiparametric MRI measurements may help understand the white matter changes and neurotoxicity upon radiation treatment in a single setting. J. Magn. Reson. Imaging 2009;29:1013,1020. © 2009 Wiley-Liss, Inc. [source] NAALADase (GCP II) inhibitors protect in models of amyotrophic lateral sclerosis (ALS)JOURNAL OF NEUROCHEMISTRY, Issue 2002A. G. Thomas Chronic glutamate toxicity is implicated in the pathogenesis of ALS. The neuropeptide N-acetyl-aspartyl glutamate (NAAG) appears to function both as a storage form for glutamate and as a neuromodulator at glutamatergic synapses. Catabolism of NAAG by N-acetylated-,-linked acidic dipeptidase (NAALADase; also termed glutamate carboxypeptidase II), yields N-acetyl aspartate (NAA) and glutamate. Since prior studies demonstrate an up-regulation of NAALADase in motor cortex and increased levels of NAA and glutamate in the CSF of ALS patients, we hypothesized that inhibition of NAALADase could protect against neuronal degeneration in ALS. Neuroprotective effects of two NAALADase inhibitors were assessed. 2-(Phosphonomethyl)pentanedioic acid (2-PMPA) decreased motor neuron loss and prevented loss of choline acetyltransferase (ChAT) activity in an in vitro model of ALS wherein chronic glutamate toxicity was induced by blocking glutamate transport. Gross morphology was preserved in 2-PMPA-treated cultures. In a SOD-1 transgenic mouse model of ALS, oral administration of a structurally different NAALADase inhibitor (GPI 5693) increased survival by 29 days and delayed onset of clinical symptoms by 17 days. Preliminary analysis of spinal cord pathology revealed severe neuronal depletion and astrocytosis with white matter changes in control mice. In mice treated with GPI 5693, normal neuronal populations with modest vacuolar changes were observed. These data suggest that NAALADase inhibition may provide an exciting therapeutic approach to the devastating disease, ALS. [source] Neuroimaging Determinants of Cognitive Performances in Stroke Associated With Small Vessel DiseaseJOURNAL OF NEUROIMAGING, Issue 2 2005V. Mok MD ABSTRACT Background and Purpose. Controversies still exist as to the neuroimaging determinants of cognitive impairment in cerebral small vessel disease (SVD). The authors studied the neuroimaging correlates of cognitive performances among patients with stroke associated with SVD. Methods. The authors per formed cerebral computed tomography, magnetic resonance imaging, and diffusion-weighted imaging among 74 consecu tive patients admitted to the acute stroke unit because of stroke associated with SVD. They examined the association between cognitive performances and the following neuroimaging features: volume of white matter changes (WMC), multiplicity of lacunae, location of lacunae, total cerebral atrophy, and frontal and medial temporal lobe atrophy. Results. Apart from age and education, univariate linear regression analyses revealed that WMC volume, presence of thalamic lacunae, cerebral atrophy, and left frontal lobe atrophy predicted performance on the Mini-Mental State Examination while WMC volume, presence of thalamic infarcts, cerebral atrophy, and frontal lobe atrophy of both sides predicted performance on the Mattis Dementia Rat ing Scale-Initiation/Preservation subscale. In the multivariate analyses, education (R2= 0.22, P < .001), left frontal lobe atrophy (R2= 0.10, P= .004), and presence of thalamic lacunae (R2= 0.04, P= .049) were found to predict performance on the Mini-Mental State Examination while age (R2= 0.23, P < .001) and presence of thalamic lacunae (R2= 0.08, P= .011) were found to predict performance on the Mattis Dementia Rating Scale-Initiation/Preservation. Conclusions. Among patients with stroke associated with SVD, thalamic lacunae and frontal lobe atrophy are key determinants of cognitive performances. [source] Water Apparent Diffusion Coefficient and T2 Changes in the Acute Stage of Maple Syrup Urine Disease: Evidence of Intramyelinic and Vasogenic-Interstitial EdemaJOURNAL OF NEUROIMAGING, Issue 2 2003Andrea Righini MD ABSTRACT Background. The acute phase of the neonatal classical form of maple syrup urine disease (MSUD) is usually associated with generalized brain edema. Methods and Results. The authors present the case of a newborn infant in the acute stage of the classical form of MSUD in whom a remarkable decrease in the water apparent diffusion coefficient (ADC) in advanced myelinating white matter areas was associated with an increase in the T2 signal. This diffusion magnetic resonance imaging (MRI) pattern appears to be compatible with a rare kind of cytotoxic edema, the so-called intramyelinic edema. At the same time, an increase in the ADC was seen in unmyelinated areas together with an increase in the T2 signal, a sign of a coexistent vasogenic-interstitial edema. Conclusions. ADC measurements in MSUD provide more specific information than conventional MRI about the pathophysiology of white matter changes. [source] Microstructural white matter changes in primary torsion dystoniaMOVEMENT DISORDERS, Issue 2 2008Maren Carbon MD Abstract Primary torsion dystonia (PTD) has been conceptualized as a disorder of the basal ganglia. However, recent data suggest a widespread pathology involving motor control pathways. In this report, we explored whether PTD is associated with abnormal anatomical connectivity within motor control pathways. We used diffusion tensor magnetic resonance imaging (DT-MRI) to assess the microstructure of white matter. We found that fractional anisotropy, a measure of axonal integrity and coherence, was significantly reduced in PTD patients in the pontine brainstem in the vicinity of the left superior cerebellar peduncle and bilaterally in the white matter of the sensorimotor region. Our data thus support the possibility of a disturbance in cerebello-thalamo-cortical pathways as a cause of the clinical manifestations of PTD. © 2007 Movement Disorder Society [source] In vivo proton MR spectroscopy findings specific for adenylosuccinate lyase deficiencyNMR IN BIOMEDICINE, Issue 5 2010M. Henneke Abstract Adenylosuccinate lyase (ADSL) deficiency is an inherited metabolic disorder affecting predominantly the central nervous system. The disease is characterized by the accumulation of succinylaminoimidazolecarboxamide riboside and succinyladenosine (S-Ado) in tissue and body fluids. Three children presented with muscular hypotonia, psychomotor delay, behavioral abnormalities, and white matter changes on brain MRI. Two of them were affected by seizures. Screening for inborn errors of metabolism including in vitro high resolution proton MRS revealed an ADSL deficiency that was confirmed genetically in all cases. All patients were studied by in vivo proton MRS. In vitro high resolution proton MRS of patient cerebrospinal fluid showed singlet resonances at 8.27 and 8.29,ppm that correspond to accumulated S-Ado. In vivo proton MRS measurements also revealed a prominent signal at 8.3,ppm in gray and white matter brain regions of all patients. The resonance was undetectable in healthy human brain. In vivo proton MRS provides a conclusive finding in ADSL deficiency and represents a reliable noninvasive diagnostic tool for this neurometabolic disorder. Copyright © 2010 John Wiley & Sons, Ltd. [source] Histological and Ultrastructural Analysis of White Matter Damage after Naturally-occurring Spinal Cord InjuryBRAIN PATHOLOGY, Issue 2 2006Peter M. Smith Detailed analysis of the structural changes that follow human clinical spinal cord injury is limited by difficulties in achieving adequate tissue fixation. This study bypasses this obstacle by examining the spinal cord from paraplegic domestic animals, enabling us to document the ultrastructural changes at different times following injury. In all but one case, injury resulted from a combination of contusion and compression. There was infarction and hemorrhage, followed by gray matter destruction and the rapid development of a variety of white matter changes including axon swelling and myelin degeneration. Axons greater than 5 µm in diameter were more susceptible to degenerative changes, whereas smaller axons, particularly those in the subpial region, were relatively well preserved. Demyelinated axons were seen within 2 weeks after injury and, at later time points, both Schwann cell and oligodendrocyte remyelination was common. More subtle white matter abnormalities were identified by examining sagittal sections, including focal accumulation of organelles in the axoplasm and partial and paranodal myelin abnormalities. These observations serve to validate observations from experimental models of spinal contusion but also highlight the complexity of naturally occurring (ie, clinical) spinal injury. They also raise the possibility that focal abnormalities such as paranodal demyelination may contribute to early axonal dysfunction and possibly to progressive tissue damage. [source] Progressive brain changes in schizophrenia: a 1-year follow-up study of diffusion tensor imagingACTA NEUROPSYCHIATRICA, Issue 6 2009Miho Ota Objective: Recent cross-sectional studies suggest that brain changes in schizophrenia are progressive during the course of the disorder. However, it remains unknown whether this is a global process or whether some brain areas are affected to a greater degree. The aim of this study was to examine the longitudinal brain changes in patients with chronic older schizophrenia by magnetic resonance imaging (MRI). Methods: Three-dimensional (3D) T1-weighted and diffusion tensor (DT) MRI were performed twice on each of 16 chronic older schizophrenia patients (mean age = 58.1 ± 6.7 years ) with an interval of 1 year between imaging sessions. To clarify the longitudinal morphological and white matter changes, volume data and normalised diffusion tensor imaging (DTI) metrics were compared between the first and follow-up studies using a paired t -test. Results: Focal cortical volume loss was observed in the left prefrontal lobe and anterior cingulate on volumetric study. In addition, DTI metrics changed significantly at the bilateral posterior superior temporal lobes, left insula, genu of the corpus callosum and anterior cingulate. Conclusion: There are ongoing changes in the brains of schizophrenic patients during the course of the illness. Discrepancies between volume data and DTI metrics may indicate that the pattern of progressive brain changes varies according to brain region. 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