Home About us Contact
|
Home About us Contact | ||
|
|
||
White Matter Disease (white + matter_disease)
Selected AbstractsDecreasing myelin density reflected increasing white matter pathology in Alzheimer's disease,a neuropathological studyINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 10 2005Martin Sjöbeck Abstract Background White matter disease (WMD) is frequently seen in Alzheimer's disease (AD) at neuropathological examination. It is defined as a subtotal tissue loss with a reduction of myelin, axons and oligodendrocytes as well as astrocytosis. Studies quantitatively defining the myelin loss in AD are scarce. The aim was to develop a method that could provide numerical values of myelin density in AD. The purpose was to compare the myelin contents in increasing grades of pathology of WMD, with age and cortical AD pathology as well as in different regions of the brain in AD. Material and methods Sixteen cases with AD and concomitant WMD were investigated with an in-house developed image analysis technique to determine the myelin attenuation with optical density (OD) in frontoparietal, parietal, temporal and occipital white matter on whole brain coronal sections stained for myelin with Luxol Fast Blue (LFB). The OD values in LFB were compared grouped according to Haematoxylin/Eosin (HE) evaluated mild, moderate and severe WMD or normal tissue. The OD values were also correlated with age and cortical AD pathology and compared between the different studied white matter regions. Results Increasing severity of WMD was associated with a statistically significant OD reduction. No correlation was seen between age and OD or overall cortical AD pathology. The OD values were significantly lower in frontoparietal-compared to occipital white matter. Conclusions Myelin loss in AD with WMD is a marked morphologic component of the disease and it is possible to determine the reduction objectively in neuropathological specimens with quantitative measures. This may be of use for clinical diagnostics including brain imaging. Copyright © 2005 John Wiley & Sons, Ltd. [source] Vanishing white matter disease: A review with focus on its geneticsDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2006Jan C. Pronk Abstract Leukoencephalopathy with vanishing white matter (VWM) is an autosomal recessive brain disorder, most often with a childhood onset. Magnetic resonance imaging and spectroscopy indicate that, with time, increasing amounts of cerebral white matter vanish and are replaced by fluid. Autopsy confirms white matter rarefaction and cystic degeneration. The process of localization and identification of the first two genes related to VWM, EIF2B5 and EIF2B2, was facilitated by two founder effects in the Dutch population. EIF2B5 and EIF2B2 encode the , and , subunits of translation initiation factor eIF2B. Soon it was shown that mutations in all five eIF2B subunit genes can cause VWM. EIF2B is essential for the initiation of translation of RNA into protein and is involved in regulation of the process, especially under stress conditions, which may explain the sensitivity to stress conditions observed in VWM patients. The pathophysiology of the disease is still poorly understood. MRDD Research Reviews 2006;12:123,128. © 2006 Wiley-Liss, Inc. [source] Neuropathological correlates to clinically defined dementia with Lewy bodiesINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2001E. Londos Abstract Objectives To analyse the neuropathological changes behind clinically defined dementia with Lewy bodies (clinDLB) compared with clinically diagnosed Alzheimer's disease (clinAD). Methods The prevalence of neuropathological findings in 48 clinDLB and 45 clinAD cases was compared. Sixteen clinDLB and 10 clinAD cases were reassessed with ,-synuclein staining for Lewy bodies (LB). Results Alzheimer pathology was found in 81% of the clinDLB and 93% of the clinAD cases. The clinDLB group had a higher prevalence of frontal white matter pathology, mostly of ischemic type, and a more severe degeneration of the substantia nigra compared with the clinAD group. In hematoxylin,eosin staining, LBs were identified in seven (15%) of the clinDLB and in four (9%) of the clinAD group. In ,-synuclein staining, 38% of the clinDLB and 40% of the clinAD cases exhibited LBs. The cases without LBs, in the clinDLB group, had AD pathology in combination with frontal white matter disease. Vascular pathology of significant degree was prevalent in more than 40% of all the cases with verified LBs regardless of clinical diagnosis. Conclusion Consecutive dementia cases, fulfilling the clinical consensus criteria for DLB, may exhibit combinations of neuropathological changes which in themselves can explain the clinical picture of DLB even when LBs are absent. Copyright © 2001 John Wiley & Sons, Ltd. [source] Diffusion time dependence of the apparent diffusion tensor in healthy human brain and white matter diseaseMAGNETIC RESONANCE IN MEDICINE, Issue 6 2001Chris A. Clark Abstract The diffusion time dependence of the brain water diffusion tensor provides information regarding diffusion restriction and hindrance but has received little attention, primarily due to limitations in gradient amplitude available on clinical MRI systems, required to achieve short diffusion times. Using new, more powerful gradient hardware, the diffusion time dependence of tensor-derived metrics were studied in human brain in the range 8,80 ms, which encompasses the shortest diffusion times studied to date. There was no evidence for a change in mean diffusivity, fractional anisotropy, or in the eigenvalues with diffusion time in healthy human brain. The findings are consistent with a model of unrestricted, but hindered water diffusion with semipermeable membranes, likely originating from the extracellular space in which the average extracellular separation is less than 7 microns. Similar findings in two multiple sclerosis plaques indicated that the size of the water diffusion space in the lesion did not exceed this dimension. Magn Reson Med 45:1126,1129, 2001. © 2001 Wiley-Liss, Inc. [source] Rapid T1 mapping using multislice echo planar imagingMAGNETIC RESONANCE IN MEDICINE, Issue 4 2001Stuart Clare Abstract Determination of neurological pathology in white matter disease can be made in a semiquantitative way from T1 - or T2 -weighted images. A higher level of quantification based on measured T1 or T2 values has been either limited to specific regions of interest or to low-resolution maps. Higher-resolution T1 maps have proved difficult to obtain due to the excessively long scan times required using conventional techniques. In this study, clinically acceptable images are obtained by using single-shot echo planar imaging (EPI) with an acquisition scheme that maximizes signal-to-noise while minimizing the scan time. Magn Reson Med 45:630,634, 2001. © 2001 Wiley-Liss, Inc. [source] Diffusion-weighted magnetic resonance imaging of white matter in bipolar disorder: a pilot studyBIPOLAR DISORDERS, Issue 2 2006William T Regenold Objective:, Diffusion-weighted magnetic resonance imaging (MRI) has shown increased sensitivity in detecting brain white matter disease compared to traditional T2-weighted MRI. Diffusion-weighted imaging (DWI) can quantitatively assess the microstructural integrity of white matter using the average apparent diffusion coefficient (ADCav), a measure of the extent to which water molecules move freely within tissue. On the basis of numerous studies suggesting white matter disease in bipolar patients, particularly patients with more severe illness, this study aimed to test the utility of DWI in assessing the white matter integrity of bipolar patients with severe illness. Methods:, The existing MRI scans of eight bipolar patients and eight age-matched controls with neurological illness were examined retrospectively. ADCav values for pixels within white matter regions of interest (ROIs) were calculated and used to plot ADCav frequency histograms for each ROI. Mean ADCav values for the two groups were then compared by ANCOVA. Results:, The bipolar mean ADCav (0.855 ± 0.051 × 10,3 mm2/s) for combined white matter ROIs significantly exceeded that of controls (0.799 ± 0.046 × 10,3 mm2/s), while covarying for age (F = 4.47, df = 3, p = 0.025). Conclusions:, This is the first report of an elevated ADCav in the white matter of a group of patients with bipolar disorder. In this group of patients with severe illness, increased white matter ADCav suggests microstructural changes consistent with decreased white matter integrity. DWI may be an additional, useful tool to assess white matter abnormalities in bipolar disorder. [source] Stroke after initiation of interferon-beta treatment for relapsing,remitting disseminated white matter diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 6 2009Article first published online: 13 NOV 200 No abstract is available for this article. [source] Stroke after initiation of interferon-beta treatment for relapsing,remitting disseminated white matter diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 6 2006B. Bosche Background,,, Interferon-beta (INF- ,) is effective and used in reducing exacerbation frequency and disease progression in multiple sclerosis. In certain circumstances, INF- , can lead to rare side effects. Aims of the study,,, We report the case of a 34-year-old female patient satisfying the McDonald criteria of multiple sclerosis without showing typical pathologic changes in cerebrospinal fluid (CSF). After introduction of INF- , treatment, she quickly developed further progression of her disseminated neurological symptoms and finally an ischemic cerebral infarction. Methods,,, Evaluation of the patient included arterial angiography, magnetic resonance and positron emission tomography, histopathological assessment as well as a broad spectrum of serum and CSF analysis. Results,,, All diagnostic evaluations and the clinical course revealed evidences for a primary angiitis of the CNS. We discuss the possible worsening due to inappropriate INF- , treatment in cerebral angiitis promoting severe cerebrovascular insufficiency. Conclusion,,, The authors suggest that all diagnostic multiple sclerosis criteria including typical CSF findings should be ascertained before INF- , treatment is initiated. [source] Grey matter pathology in multiple sclerosisACTA NEUROLOGICA SCANDINAVICA, Issue 2006L. Bö Although multiple sclerosis (MS) has been considered a white matter disease, MS lesions are known to occur in grey matter. Recent immunohistochemical studies have demonstrated extensive grey matter demyelination in chronic MS. The most common lesion type consists of purely cortical lesions extending inward from the surface of the brain, this lesion subgroup is grossly underestimated by standard histochemical myelin staining methods. Some MS patients have subpial demyelination in all cortical areas of the brain; this pattern has been termed ,,general cortical subpial demyelination''. Extensive cortical demyelination is associated with the progressive phases of disease, as less cortical demyelination has been detected in relapsing-remitting MS. The pathology of grey matter lesions differs from that of white matter lesions; grey matter lesions are less inflammatory, with less macrophage and lymphocyte infiltration. In purely cortical lesions there is no significant increase in lymphocytes compared with non-demyelinated adjacent cortical areas in MS patients or cerebral cortex in control patients. Significant axonal transection and neuronal loss have been demonstrated in grey matter MS lesions. Current magnetic resonance imaging (MRI) methods are not sensitive for purely cortical MS lesions. The clinical significance of cortical MS lesions may not be characterised until more sensitive MRI methods are developed. [source] Sonographic detection of the optic radiationACTA PAEDIATRICA, Issue 10 2005Annemieke Boxma Abstract Objective: To describe a region of hyperechoic white matter adjacent to the atrium of the lateral ventricle of preterms, and to speculate on the relevance of detecting preterm white matter injury. Patients and methods: Cranial ultrasound images of 92 preterms of gestational age (GA) 32 wk or less were reviewed. For each infant, one first week standard coronal image was used for measurement of grey values around the para-atrial region of interest (PAROI) relative to the choroid plexus. For verification of the sonographic anatomy, MR images of an adult brain were used. For reference, neuro-anatomical images were compared in several atlases. In a group of nine preterms of similar GA with cystic periventricular leukomalacia (PVL) or MR-confirmed white matter disease, the disappearance of the PAROI was examined. Results: The hyperechoic para-atrial area, subjectively detected in 84% of the patients, was situated bilaterally between the inner end of the lateral fissure and the upper third of the choroid plexus. In white matter caudal to the atrium, the hyperechoic band could be pursued towards the calcarine area. The average ratio of grey value around the PAROI to the choroid plexus was 0.787 (SD=0.072, median 0.791). There was no correlation between PAROI grey value and gestational age. At 26 wk gestational age, the average ratio was 0.781 (n=14), and 0.789 (n=17) at 31 wk. Location of the PAROI agrees with the angle of the upper loop of the optic radiation. None of the nine infants with white matter damage had PAROIs clearly distinguishable from flaring. Conclusion: The symmetrical and unchanged acoustic character between 26 and 31 wk of gestational age argues in favour of the hypothesis that the PAROI is an anatomical structure. The localization of the hyperechoic band supports the hypothesis that it represents part of the optic radiation. Further study is needed to examine the absence of a hyperechoic para-atrial band as a prognostic marker of the extension and severity of white matter injury. [source] Applications of diffusion-weighted and diffusion tensor MRI to white matter diseases , a reviewNMR IN BIOMEDICINE, Issue 7-8 2002Mark A. Horsfield Abstract This paper reviews the current applications of diffusion-weighted and diffusion tensor MRI in diseases of the brain white matter. The contribution that diffusion-weighted imaging has made to our understanding of white matter diseases is critically appraised. The quantitative nature of diffusion MRI is one of its major attractions; however, this is offset by the more advanced hardware required to collect diffusion-weighted images reliably, and the more complex processing to produce quantitative parametric diffusion images. With the now common availability of scanners equipped to perform echo-planar imaging, the acquisition of diffusion tensor images is sure to become more widespread and routine. Copyright © 2002 John Wiley & Sons, Ltd. [source] Immunoglobulins and complement in postmortem multiple sclerosis tissue,ANNALS OF NEUROLOGY, Issue 1 2009Michael H. Barnett MBBS Objective To identify evidence of a discrete, specific immune response in multiple sclerosis (MS) by analyzing the distribution of immunoglobulins and complement in tissue derived from cases of MS, and from control inflammatory white matter diseases known to express viral and autoantigens in the brain and spinal cord. Methods Autopsy tissue from 25 MS patients and 24 patients with other neurological diseases was examined immunohistochemically for immunoglobulins and activated complement (C3d and C9neo). Results In tissue remote from focal lesions in MS and other neurological diseases, IgG was detected in many normal structures but not in myelin or ramified microglia. Disrupted myelin in areas of active myelin breakdown and in phagocytes stained positively for C3d and C9neo, and equivocally for IgG in MS and all other neurological diseases examined, including ischemic infarcts. Disease-specific deposits of IgG or complement were detected in virus-infected cells in progressive multifocal leukoencephalopathy, subacute sclerosing panencephalitis, and cytomegalovirus encephalitis; in glial-limiting membranes in neuromyelitis optica; and in senile plaques in Alzheimer's dementia. Specific to MS were unusual microglial nodules containing short, linear deposits of activated complement (C3d) on partly demyelinated axons located in normal-appearing periplaque white matter. Interpretation IgG and complement immunostaining of disrupted myelin in MS lesions, frequently cited as an indication of pathogenic anti-myelin antibodies, is a nonspecific feature that cannot be interpreted as evidence of a distinct pathogenesis or serve to define particular variants of the disease. The unusual microglial nodules described in this study may constitute a specific biomarker with pathogenetic significance in MS. Ann Neurol 2009;65:32,46 [source] | |||||||||||||||||||