• Gang Guo; Yonggui Yang; Weiqun Yang 2012-01-01 We performed a retrospective analysis of non-contrast computed tomography (CT) scans, immediately subsequent magnetic resonance imaging (MRI), and cerebral angiography data from 30 consecutive patients with acute ischemic stroke within 6 hours after symptom onset. Results showed that eleven patients developed subsequent hemorrhagic transformation at follow-up. A hyperintense middle cerebral artery sign on MRI was found in six hemorrhagic patients, all of who had acute thrombosis formation on magnetic resonance angiography and digital subtraction angiography. No patients in the non-hemorrhagic group had hyperintense middle cerebral artery sign on MRI. The sensitivity, specificity, and positive predictive values of the hyperintense middle cerebral artery sign on MRI T1-weighted image for subsequent hemorrhagic transformation were 54.5%, 100%, and 100% respectively. Hyperdense middle cerebral artery sign on non-contrast CT was observed in nine patients, five of who developed hemorrhagic transformation. These data suggest that hyperintense middle cerebral artery sign on MRI T1-weighted image is a highly specific and moderately sensitive indicator of subsequent hemorrhagic transformation in patients after acute ischemic stroke, and its specificity is superior to CT. • Marstrand, J.R.; Garde, E; Rostrup, Egill 2002-01-01 BACKGROUND AND PURPOSE: There is growing evidence that white matter hyperintensities (WMH) should not be considered as benign age-dependent changes on MR images but indicate pathological changes with clinical consequences. • Besuchen Sie den BMI-Rechner Webseite und geben Sie. Und erreichbares Ziel Gewichtsverlust. Von Cholesterin und andere feste. Previous studies comparing subjects with WMH to normal controls have repor. • Samuel N Lockhart Full Text Available The mechanisms by which aging and other processes can affect the structure and function of brain networks are important to understanding normal age-related cognitive decline. Advancing age is known to be associated with various disease processes, including clinically asymptomatic vascular and inflammation processes that contribute to white matter structural alteration and potential injury. The effects of these processes on the function of distributed cognitive networks, however, are poorly understood. We hypothesized that the extent of magnetic resonance imaging white matter hyperintensities would be associated with visual attentional control in healthy aging, measured using a functional magnetic resonance imaging search task. We assessed cognitively healthy older adults with search tasks indexing processing speed and attentional control. Expanding upon previous research, older adults demonstrate activation across a frontal-parietal attentional control network. Further, greater white matter hyperintensity volume was associated with increased activation of a frontal network node independent of chronological age. Also consistent with previous research, greater white matter hyperintensity volume was associated with anatomically specific reductions in functional magnetic resonance imaging functional connectivity during search among attentional control regions. White matter hyperintensities may lead to subtle attentional network dysfunction, potentially through impaired frontal-parietal and frontal interhemispheric connectivity, suggesting that clinically silent white matter biomarkers of vascular and inflammatory injury can contribute to differences in search performance and brain function in aging, and likely contribute to advanced age-related impairments in cognitive control. • Lockhart, Samuel N.; Luck, Steven J.; Geng, Joy; Beckett, Laurel; Disbrow, Elizabeth A.; Carmichael, Owen; DeCarli, Charles 2015-01-01 The mechanisms by which aging and other processes can affect the structure and function of brain networks are important to understanding normal age-related cognitive decline. Advancing age is known to be associated with various disease processes, including clinically asymptomatic vascular and inflammation processes that contribute to white matter structural alteration and potential injury. The effects of these processes on the function of distributed cognitive networks, however, are poorly understood. We hypothesized that the extent of magnetic resonance imaging white matter hyperintensities would be associated with visual attentional control in healthy aging, measured using a functional magnetic resonance imaging search task. We assessed cognitively healthy older adults with search tasks indexing processing speed and attentional control. Expanding upon previous research, older adults demonstrate activation across a frontal-parietal attentional control network. Further, greater white matter hyperintensity volume was associated with increased activation of a frontal network node independent of chronological age. Also consistent with previous research, greater white matter hyperintensity volume was associated with anatomically specific reductions in functional magnetic resonance imaging functional connectivity during search among attentional control regions. White matter hyperintensities may lead to subtle attentional network dysfunction, potentially through impaired frontal-parietal and frontal interhemispheric connectivity, suggesting that clinically silent white matter biomarkers of vascular and inflammatory injury can contribute to differences in search performance and brain function in aging, and likely contribute to advanced age-related impairments in cognitive control. PMID:25793922 • Overdorp, E.J.; Kessels, R.P.C.; Claassen, J.A.H.R.; Oosterman, J.M. 2014-01-01 In this retrospective study, we investigated the independent effects of white matter hyperintensities (VVMH) and hippocampal atrophy on cognitive functions in a broad sample of patients seen in a memory clinic. To ensure generalizability, these associations were examined irrespective of diagnosis an • Overdorp, E.J.; Kessels, R.P.C.; Claassen, J.A.H.R.; Oosterman, J.M. 2014-01-01 In this retrospective study, we investigated the independent effects of white matter hyperintensities (WMH) and hippocampal atrophy on cognitive functions in a broad sample of patients seen in a memory clinic. To ensure generalizability, these associations were examined irrespective of diagnosis and • Miyazaki, Masahito; Hashimoto, Toshiaki; Tayama, Masanobu; Kuroda, Yasuhiro (Tokushima Univ. School of Medicine) 1992-05-01 Magnetic resonance imaging was performed in 270 patients with various neurologic complaints (1-15Y) with a 0.5 tesla superconducting imaging system using a field echo T1-weighted sequence and spin echo T2-weighted and PD-weighted sequences. Twenty-seven of them had deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images. The frequency of mild DWMH differed in different age groups, suggesting that mild DWMH may result from delayed myelination in the central nervous system. However, the frequency of severe DWMH, which was revealed as isointense relative to cerebrospinal fluid, did not differ in different age groups and it was significantly more common in severely retarded patients. Classification of DWMH based on the signal intensity is valuable to distinguish white matter abnormalities in the occipital lobe from delayed myelination in the same site. • Maya Thomas 2012-01-01 Full Text Available Subacute sclerosing panencephalitis (SSPE is chronic encephalitis occurring after infection with measles virus. An 8-year-old boy presented with progressive behavioral changes, cognitive decline and myoclonic jerks, progressing to a bed bound state over 2 months. Magnetic resonance imaging (MRI brain showed T2-weighted hyperintensities in the subcortical areas of the left occipital lobe and brachium of the inferior colliculus on both sides. EEG showed bilateral, synchronous periodic discharges. Serum/cerebrospinal fluid measles IgG titer was significantly positive. The overall features were suggestive of SSPE. MRI finding of bilateral inferior colliculus changes on MRI without significant involvement of other commonly involved areas suggests an uncommon/rare imaging pattern of SSPE. • Arimura, Hidetaka; Kawata, Yasuo; Yamashita, Yasuo; Magome, Taiki; Ohki, Masafumi; Toyofuku, Fukai; Higashida, Yoshiharu; Tsuchiya, Kazuhiro 2010-03-01 We have developed a computerized evaluation method of white matter hyperintensity (WMH) regions for the diagnosis of vascular dementia (VaD) based on magnetic resonance (MR) images, and implemented the proposed method as a graphical interface program. The WMH regions were segmented using either a region growing technique or a level set method, one of which was selected by using a support vector machine. We applied the proposed method to MR images acquired from 10 patients with a diagnosis of VaD. The mean similarity index between WMH regions determined by a manual method and the proposed method was 78.2+/-11.0%. The proposed method could effectively assist neuroradiologists in evaluating WMH regions. • Salem, Lise C; Hejl, Anne-Mette; Garde, Ellen; 2011-01-01 Prepulse inhibition (PPI) of the startle response, a measure for sensorimotor gating, exhibits a relatively high inter-individual variability in elderly subjects. The aim of this study was to investigate whether white matter hyperintensities (WMH), frequently identified on cranial magnetic. Resonance imaging (MRI) in elderly subjects with and without cognitive impairment, may contribute to variations in PPI. A passive acoustic PPI paradigm was applied in 92 human subjects (53 healthy and 39 patients with Alzheimer's disease or mild cognitive impairment) between 60 and 85years of age. Rated visually on craniel MRI FLAIR images using the Fazekas scale. WMH were identified in 70% of all subjects. The latency to peak of the startle response increased significantly with increasing WMH load, whereas the inhibition of the startle response (PPI) was neither significantly related. • Marstrand, J.R.; Garde, E; Rostrup, Egill; 2002-01-01 BACKGROUND AND PURPOSE: There is growing evidence that white matter hyperintensities (WMH) should not be considered as benign age-dependent changes on MR images but indicate pathological changes with clinical consequences. Previous studies comparing subjects with WMH to normal controls have. Reported global reductions in cerebral blood flow (CBF) and cerebral vascular reactivity. In this study, we examined localized hemodynamic status to compare WMH to normal appearing white matter (NAWM). METHODS: A group of 21 normal 85-year-old subjects were studied using dynamic contrast-enhanced MRI. Together with administration of acetazolamide. From a combination of anatomic images with different signal weighting, regions of interest were generated corresponding to gray and white matter and WMH. Localized measurements of CBF and cerebral blood volume (CBV) and mean transit time were obtained directly. • Yoon-Sang Oh 2013-10-01 Full Text Available Background and Purpose: Several reports on the elderly population have suggested that orthostatic hypotension is associated with white matter hyperintensities (WMH; however, little information is available on patients with Parkinson’s disease (PD. Methods: We analyzed the association blood pressure profiles during tilt table testing with WMH scores in 117 patients with PD. WMH were rated using the semiquantitative visual rating system proposed by Scheltens et al. Results: The presence of orthostatic hypotension was associated with increasing tendency of WMH score and the blood pressure changes during tilting and supine blood pressure were positively correlated with increasing WMH score. Conclusions: This finding indicates that hemodynamic changes associated with orthostatic hypotension may be associated with white matter changes in patients with PD. • van Straaten, EC; Fazekas, F; Rostrup, Egill; 2006-01-01 between groups with and without symptoms. METHODS: We used data of 618 independently living elderly with WMH collected in the Leukoaraiosis And DISability (LADIS) study. Subjects with and without symptoms of depression, gait disturbances, urinary incontinence, and memory decline were compared with respect.BACKGROUND AND PURPOSE: White matter hyperintensities (WMH) are associated with decline in cognition, gait, mood, and urinary continence. Associations may depend on the method used for measuring WMH. We investigated the ability of different WMH scoring methods to detect differences in WMH load. And Mann-Whitney tests. In addition, the punctate and confluent lesion type with comparable WMH volume were compared with respect to the clinical data using Student t test and chi2 test. Direct comparison of visual ratings with volumetry was done using curve fitting. RESULTS: Visual and volumetric. • Lockhart, Samuel N.; Roach, Alexandra E.; Luck, Steven J.; Geng, Joy; Beckett, Laurel; Carmichael, Owen; DeCarli, Charles 2014-01-01 A fundamental controversy is whether cognitive decline with advancing age can be entirely explained by decreased processing speed, or whether specific neural changes can elicit cognitive decline, independent of slowing. These hypotheses are anchored by studies of healthy older individuals where age is presumed the sole influence. Unfortunately, advancing age is also associated with asymptomatic brain white matter injury. We hypothesized that differences in white matter injury extent, manifest by MRI white matter hyperintensities (WMH), mediate differences in visual attentional control in healthy aging, beyond processing speed differences. We tested young and cognitively healthy older adults on search tasks indexing speed and attentional control. Increasing age was associated with generally slowed performance. WMH was also associated with slowed search times independent of processing speed differences. Consistent with evidence attributing reduced network connectivity to WMH, these results conclusively demonstrate that clinically silent white matter injury contributes to slower search performance indicative of compromised cognitive control, independent of generalized slowing of processing speed. PMID:24183716 • Gaist, David; Garde, Ellen; Blaabjerg, Morten 2016-01-01 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.% 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. • Jayalakshmi Sita 2006-01-01 Full Text Available Abnormal high signal in the globus pallidus on T1 weighted magnetic resonance imaging (MRI of the brain has been well described in patients with chronic liver disease. It may be related to liver dysfunction or portal-systemic shunting. We report a case of extra hepatic portal vein obstruction with portal hypertension and esophageal varices that presented with extra pyramidal features. T1 weighted MRI brain scans showed increased symmetrical signal intensities in the basal ganglia. Normal hepatic function in this patient emphasizes the role of portal- systemic communications in the development of these hyperintensities, which may be due to deposition of paramagnetic substances like manganese in the basal ganglia. • Thomas Samaille Full Text Available White matter hyperintensities (WMH on T2 or FLAIR sequences have been commonly observed on MR images of elderly people. They have been associated with various disorders and have been shown to be a strong risk factor for stroke and dementia. WMH studies usually required visual evaluation of WMH load or time-consuming manual delineation. This paper introduced WHASA (White matter Hyperintensities Automated Segmentation Algorithm, a new method for automatically segmenting WMH from FLAIR and T1 images in multicentre studies. Contrary to previous approaches that were based on intensities, this method relied on contrast: non linear diffusion filtering alternated with watershed segmentation to obtain piecewise constant images with increased contrast between WMH and surroundings tissues. WMH were then selected based on subject dependant automatically computed threshold and anatomical information. WHASA was evaluated on 67 patients from two studies, acquired on six different MRI scanners and displaying a wide range of lesion load. Accuracy of the segmentation was assessed through volume and spatial agreement measures with respect to manual segmentation; an intraclass correlation coefficient (ICC of 0.96 and a mean similarity index (SI of 0.72 were obtained. WHASA was compared to four other approaches: Freesurfer and a thresholding approach as unsupervised methods; k-nearest neighbours (kNN and support vector machines (SVM as supervised ones. For these latter, influence of the training set was also investigated. WHASA clearly outperformed both unsupervised methods, while performing at least as good as supervised approaches (ICC range: 0.87-0.91 for kNN; 0.89-0.94 for SVM. Mean SI: 0.63-0.71 for kNN, 0.67-0.72 for SVM, and did not need any training set.
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