Abstract T P89: Unilateral Cerebral Atrophy Secondary to Extracranial Carotid Stenosis

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Shahram Khalid ◽  
Navid Seraji-bozorgzad
Keyword(s):  
White Matter ◽  
Carotid Stenosis ◽  
Gray Matter ◽  
Statistical Significance ◽  
Cerebral Atrophy ◽  
Tissue Type ◽  
Total Brain Volume ◽  
Brain Images ◽  
Asymptomatic Patients ◽  
Bilateral Carotid

Background: Moderate to severe or bilateral carotid stenosis is associated with cerebral atrophy and cognitive decline. Prior studies have evaluated global atrophy and its correlation with the degree of stenosis. It is unclear whether carotid stenosis can lead to unilateral cerebral changes. Objective: To evaluate for unilateral cerebral atrophy in asymptomatic patients with moderated to severe extracranial unilateral carotid stenosis. Methods: Subjects were selected from patients who had undergone carotid vascular imaging and MRI of the brain, from January 2007 to January 2013 at our institution. Patients with history of TIA or ischemic stroke were excluded. Carotid stenosis (CS) group consisted of patients with unilateral moderate to severe carotid stenosis (n=9). Patients without any stenosis (n=5) were used as controls. T1-weighted brain images (FOV 256 x 256 x128, resolution 1.5 x 1.5 x 5 mm) were registered to Talairach space using FSL software. Non-brain tissue was removed using the BET module. Segmentation into gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) was done with the FAST tool. Total brain volume (TBV) was calculated as the sum of three tissue types (GM + WM + CSF). Total number of voxels in each hemisphere was calculated for GM, WM and CSF. Index of Asymmetry (IoA), was defined as the absolute value of inter-hemispheric voxel difference divided by TBV. IoA for each tissue type was compared between subjects and controls using Student’s t-test. Results: Mean age was 63.7±7.8 and 57.4 ±6.0 for the CS and control groups, respectively. Average gray matter IoA for CS was significantly increased compared to controls (1.4% v. 0.7, p < 0.02). Average white matter IoA was similar between the groups (0.6% v. 0.7%, p< 0.36). There was a trend for increased CSF IoA in the CS group compared to controls, but it did not reach statistical significance (1.8% v. 0.9%, p < 0.10). Conclusion: Moderate to severe carotid stenosis can lead to unilateral cerebral atrophy in the absence of other neurological symptoms. Further prospective studies with larger cohorts of the patients are required.

scholarly journals Stress-induced anatomical changes in white and gray matter: a review of literature

2020 ◽  
Vol 76 (06) ◽  
pp. 6400-2020
Author(s):  
IWONA ŁUSZCZEWSKA-SIERAKOWSKA ◽  
KAMIL JONAK
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Traumatic Event ◽  
Gray Matter Volume ◽  
Hippocampal Neurogenesis ◽  
Anterior Cingulate ◽  
Total Brain Volume ◽  
Extreme Stress ◽  
Mri Morphometry ◽  
The Right

Post traumatic stress disorder (PTSD) is a psychiatric abnormality caused by a drastic traumatic event or extreme stress, that exceeds the capability to adapt. There are many papers reporting anatomical brain changes induced by trauma and extreme stress, not only in white matter but in gray matter as well. Extreme stress and trauma are connected with elevation of cortisol level, which may cause damage to the hippocampus and may interfere with the anatomy of the hippocampus as well as its microstructure and cell number. Stress may inhibit the hippocampal neuroregeneration as well as hippocampal neurogenesis and even induce neuronal death within the hippocampus. Diffusor tensor imaging (DTI) is a powerful method enabling the visualization of the microstructure integrity of white matter, to evaluate the changes (rate and directionality) of water diffusion within myelin tracts and provide enhanced images of white matter tracts compared to traditional MRI morphometry images. One can evaluate the differences in white matter using fractional anisotropy (FA), which is a scalar metric of the degree of anisotropy and diffusion direction of water molecules, indicating fiber density, mylination and axon diameter. Many studies report reduced gray matter volume caused by extreme stress or trauma in people both with the diagnosis of PTSD as well as stress-exposed non PTSD in comparison to healthy controls. Studies have revealed reduced volume mostly in the hippocampus but also in regions such as anterior cingulate, corpus callosum, insula, septum pellucidum, subcallosal cortex, amygdala, prefrontal cortex and total brain volume. The right hippocampus may be prone to the effect of stress much more than the left hippocampus. Moreover, comparing trauma-exposed non-PTSD and PTSD participants, they have found volumetric abnormalities only within the right hippocampus among the PTSD group. They suggest an additional pathological process underlying PTSD, connected with the right hippocampus volume.

scholarly journals Uncommon Etiology for Seizure: Cerebral Hyperperfusion Syndrome

2017 ◽  
Vol 2017 ◽  
pp. 1-3 ◽  
Author(s):  
Mohankumar Kurukumbi ◽  
Ahn Truong ◽  
Naghemeh Pirsaharkhiz
Keyword(s):  
White Matter ◽  
Carotid Artery ◽  
Carotid Stenosis ◽  
Rare Complication ◽  
Subcortical White Matter ◽  
Cerebral Hyperperfusion Syndrome ◽  
Hyperperfusion Syndrome ◽  
Cerebral Hyperperfusion ◽  
Bilateral Carotid ◽  
The Right

Cerebral hyperperfusion syndrome (CHS) is a rare life-threatening complication of carotid endarterectomy (CEA) and carotid artery stenting (CAS) for carotid artery stenosis. The incidence varies between 0 and 3%, depending on the severity of the stenosis, perioperative hypertension, and contralateral carotid stenosis. This case report reports a 53-year-old female patient presenting with decreased alertness and multiple tonic-clonic seizures, in the background of bilateral CEA. She was found to have bilateral carotid stenosis. Her left CEA was performed three months prior and right CEA was four days prior to her current presentation with seizures. After bilateral CEA, the imaging showed extensive pathologic process involving primarily the subcortical white matter and overlying cortex, more on the right cerebral hemisphere. On follow-up six weeks later, she reported no recurrent seizures and imaging showed decrease in abnormal signal intensity of the grey and white matter. This was indicative of near complete resolution of hyperperfusion damage. CHS is a rare complication due to the loss of autoregulation of the cerebrovascular system and increased blood flow status after bilateral CEA. This case is reported because of a rare and unique presentation of seizures in the background of bilateral CEA.

Analysis of risk factors and diseases associated with atherosclerosis in the progression of carotid artery stenosis

Vascular ◽  
2015 ◽  
Vol 24 (1) ◽  
pp. 59-63 ◽  
Author(s):  
Nayara Cioffi Batagini ◽  
Erasmo Simão da Silva ◽  
Carlos AV Pinto ◽  
Pedro Puech-Leão ◽  
Nelson de Luccia
Keyword(s):  
Risk Factors ◽  
Carotid Stenosis ◽  
Statistical Significance ◽  
Carotid Bifurcation ◽  
Inflammatory Factors ◽  
Plasma Urea ◽  
Atherosclerotic Stenosis ◽  
Asymptomatic Patients ◽  
Group I ◽  
Group Ii

Objective The objective of this study was to analyze the roles of demographic, clinical, and laboratory factors on the progression of atherosclerotic stenosis in carotid bifurcation. It was based on prospective information from records entered on a specific application form for follow-up outpatients at a tertiary university service. Methods Consecutive symptomatic and asymptomatic patients ( n = 210) who had undergone more than one carotid duplex scan but no surgical intervention were selected for the analysis. The patients were divided into two groups: patients whose duplex scans did not show bilateral progression of carotid stenosis and patients with carotid stenosis progression of <50%, 50%–69%, or >70%. Clinical and demographic parameters were compared between groups. Results Group II levels of plasma urea (51.6 ± 27.8 mg/dl) and fibrinogen (493.2 ± 113.3 mg/dl) were higher than the Group I levels (43.0 ± 14.9 mg/dl and 441.3 ± 106.7 mg/dl, respectively) with statistical significance (p urea = 0.013 and p fibrinogen = 0.018). Paradoxically, the mean body mass index was higher in Group I (26.4 ± 4.6 kg/m2) than in Group II (24.6 ± 3.9 kg/m2; p = 0.02). Conclusions Traditional risk factors for the development of atherosclerosis in a carotid bifurcation are important but not unique. Metabolic and inflammatory factors can contribute to disease progression.

scholarly journals Brainstem volumetric alterations in children with autism

2008 ◽  
Vol 39 (8) ◽  
pp. 1347-1354 ◽  
Author(s):  
R. J. Jou ◽  
N. J. Minshew ◽  
N. M. Melhem ◽  
M. S. Keshavan ◽  
A. Y. Hardan
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Gray Matter Volume ◽  
Children With Autism ◽  
Sensory Profile ◽  
Sensory Sensitivity ◽  
Total Brain Volume ◽  
Matter Volume ◽  
Before And After ◽  
Mri Scans

BackgroundAlthough several studies have examined brainstem volume in autism, results have been mixed and no investigation has specifically measured gray- and white-matter structures. The aim of this investigation was to assess gray- and white-matter volumes in children with autism.MethodSubjects included 22 right-handed, non-mentally retarded boys with autism and 22 gender- and age-matched controls. Magnetic resonance imaging (MRI) scans were obtained using a 1.5-T scanner and volumetric measurements were performed using the BRAINS2 software package. Gray- and white-matter volumes were measured using a semi-automated segmentation process.ResultsThere were no significant differences in age and total brain volume (TBV) between the two groups but full-scale IQ was higher in controls. A decrease in brainstem gray-matter volume was observed in the autism group before and after controlling for TBV. No significant differences were observed in white-matter volume. A significant relationship was observed between brainstem gray-matter volume and oral sensory sensitivity as measured by the Sensory Profile Questionnaire (SPQ).ConclusionsFindings from this study are suggestive of brainstem abnormalities in autism involving gray-matter structures with evidence supporting the existence of a relationship between these alterations and sensory deficits. These results are consistent with previous investigations and support the existence of disturbances in brainstem circuitry thought to be implicated in the sensory dysfunction observed in autism.

scholarly journals MAP–Based Framework for Segmentation of MR Brain Images Based on Visual Appearance and Prior Shape

2013 ◽  
Author(s):  
Amir Alansary ◽  
Ahmed Soliman ◽  
Fahmi Khalifa ◽  
Ahmed Elnakib ◽  
Mahmoud Mostapha ◽  
...  
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Empirical Distribution ◽  
Brain Structures ◽  
Shape Prior ◽  
Unsupervised Segmentation ◽  
Brain Images ◽  
Visual Appearance ◽  
Mr Brain Images ◽  
Mr Brain

We propose a new MAP-based technique for the unsupervised segmentation of different brain structures (white matter, gray matter, etc.) from T1-weighted MR brain images. In this paper, we follow a procedure like most conventional approaches, in which T1-weighted MR brain images and desired maps of regions (white matter, gray matter, etc.) are modeled by a joint Markov-Gibbs Random Field model (MGRF) of independent image signals and interdependent region labels. However, we specifically focus on the most accurate model identification that can be achieved. The proposed joint MGRF model accounts for the following three descriptors: i) a 1st-order visual appearance descriptor(empirical distribution of signal intensity), ii) a 3D probabilistic shape prior, and iii) a 3D spatially invariant 2nd-order homogeneity descriptor. To better specify the 1st-order visual appearance descriptor, each empirical distribution of signals is precisely approximated by a Linear Combination of Discrete Gaussians (LCDG) having both positive and negative components. The 3D probabilistic shape prior is learned using a subset of 3D co-aligned training T1-weighted MR brain images. The 2nd-order homogeneity descriptor is modeled by a 2nd-order translation and rotation invariant MGRF of 3D T1-weighted MR brain region labels with analytically estimated potentials. The initial segmentation, based on a 1st-order visual appearance and 3D probabilistic shape, is then iteratively refined using a 3D MGRF model with analytically estimated potentials. Experiments on twelve 3D T1-weighted MR brain images confirm the high accuracy of the proposed approach.

scholarly journals Cerebral Blood Flow, Brain Volume, and Age Predicts Executive Function in Sickle Cell Anemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 976-976
Author(s):  
Kemar V. Prussien ◽  
Bruce E. Compas ◽  
Rachel Siciliano ◽  
R. Sky Jones ◽  
Abagail E. Ciriegio ◽  
...  
Keyword(s):  
Working Memory ◽  
Executive Function ◽  
White Matter ◽  
Children And Adolescents ◽  
Gray Matter ◽  
Brain Volume ◽  
Gray Matter Volume ◽  
Total Brain Volume ◽  
Matter Volume ◽  
Total Brain

Abstract Introduction: Individuals with sickle cell anemia (SCA) are at increased risk for deficits in multiple domains of neurocognitive functioning, including executive functions. In addition to assessing the effects of silent cerebral infarcts (SCI) and stroke on cognition, prior research has focused on hemoglobin and transcranial Doppler velocity as hemodynamic correlates. Recent studies have begun to use more precise measures of blood delivery to the brain (e.g., cerebral blood flow; CBF) to determine more sensitive indicators of cognitive risk prior to neurological injury. Nevertheless, empirical and meta-analytic findings suggest that these deficits increase with age, which can have broad impact on psychosocial functioning, including self-management and navigation through the transition from pediatric to adult medical care. This study aimed to assess brain volume as a mediator of the association between CBF and executive functioning in a sample of individuals with SCA. The secondary aim was to assess age as a moderator of hemodynamic and structural correlates of executive function. Methods: Children, adolescents, and young adults with SCA were enrolled prospectively. Each participant received a 3-Tesla non-contrast magnetic resonance imaging and magnetic resonance angiography of the brain, and a neurological examination by the study neurologist. Gray matter CBF was calculated from pseudo-continuous arterial spin labeling using the solution to the flow-modified Bloch equation after correcting for individual hematocrit. Three measures of brain volume were also computed from 3D-T1 images using Freesurfer version 7.1.1: total brain volume, gray matter volume, and white matter volume was calculated as the difference between the two. At a separate study visit, participants completed an age-appropriate Wechsler Working Memory Index (WMI). Pearson correlations assessed bivariate associations among variables, SPSS PROCESS macro was used to test gray matter volume as a mediator in the relation between CBF and working memory, and multiple linear regression analyses tested age as a moderator of the impact of CBF and brain volume on working memory. Results: Twenty-nine children and adolescents (ages 6 to 17 years) and 25 adults (ages 18 to 31 years) were enrolled. Five participants were excluded from analyses due to history of overt stroke that resulted in significant brain volume loss. Of 49 included participants, 20 had SCIs. Working memory was inversely correlated with age (r = -.30, p = .037) and CBF (r = -.36, p = .013), such that WMI decreased cross-sectionally with older age and higher CBF. Working memory was positively correlated with gray matter volume (r = .42, p = .002); however, it was not related to white matter volume (r = -.05, p = .715) or total brain volume (r = -.07, p = .642). Finally, patient age was positively correlated with CBF (r = .36, p = .014), but the association of age with gray matter volume did not reach statistical significance (r = -.27, p = .065). Analyses in Figure 1 show that although CBF and gray matter were directly related to working memory (path c and path b, respectively), gray matter volume did not mediate the association between CBF and working memory (path a*b). However, regression analyses (Table 1) showed that age moderated the association between gray matter volume and working memory, such that there was only a significant relation in children and adolescents. This association did not exist for young adults (Figure 2). Conclusions: Neurocognitive assessments has been cited as an important standard of care for children and adolescents with SCA. Given the increase in deficits with age, and the increase in mortality after transferring from pediatric to adult care, monitoring executive function abilities and potential impact on self-management should continue into adulthood. Findings from the current study provide preliminary evidence that cerebral hemodynamic compensation with elevated CBF may be insufficient to prevent gray matter volume loss in children and adolescents and decline in working memory ability. Some limitations of the current study include small sample size and whole brain gray and white matter volumes as opposed to specific regions relevant to executive functions (e.g., prefrontal cortex); however, findings from global measures provide promising evidence for future research on hemodynamic and structural predictors of executive function in SCA. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

scholarly journals Optimizing the fitting initial condition for the parallel intrinsic diffusivity in NODDI: An extensive empirical evaluation

2019 ◽  
Author(s):  
Jose M. Guerrero ◽  
Nagesh Adluru ◽  
Barbara B. Bendlin ◽  
H. Hill Goldsmith ◽  
Stacey M. Schaefer ◽  
...  
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Empirical Evaluation ◽  
Free Water ◽  
B Value ◽  
Tissue Type ◽  
Estimated Parameters ◽  
Diffusion Weighting ◽  
Model Residuals ◽  
And Diffusion

AbstractPurposeNODDI is widely used in parameterizing microstructural brain properties. The model includes three signal compartments: intracellular, extracellular, and free water. The neurite compartment intrinsic parallel diffusivity (d‖) is set to 1.7 µm2⋅ms−1, though the effects of this assumption have not been extensively explored. This work seeks to optimize d‖ by minimizing the model residuals.MethodsThe model residuals were evaluated in function of d‖ over the range from 0.5 to 3.0 µm2⋅ms−1. This was done with respect to tissue type (i.e., white matter versus gray matter), sex, age (infancy to late adulthood), and diffusion-weighting protocol (maximum b-value). Variation in the estimated parameters with respect to d‖ was also explored.ResultsResults show the optimum d‖ is significantly lower for gray matter relative to 1.7 µm2⋅ms−1 and to white matter. Infants showed significantly decreased optimum d‖ in gray and white matter. Minor optimum d‖ differences were observed versus diffusion protocol. No significant sex effects were observed. Additionally, changes in d‖ resulted in significant changes to the estimated NODDI parameters.ConclusionFuture implementations of NODDI would benefit from d‖ optimization, particularly when investigating young populations and/or gray matter.

FT-IR microspectroscopic analysis of diseased white matter brain tissues

1995 ◽  
Vol 53 ◽  
pp. 968-969
Author(s):  
Steven M. Le Vine ◽  
David L. Wetzel
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Twitcher Mouse ◽  
Grid Pattern ◽  
Marked Contrast ◽  
Spatially Resolved ◽  
Ft Ir ◽  
Ir Microspectroscopy ◽  
Chemical Evidence

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.

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