scholarly journals In vivo Magnetization Transfer MRI Shows Dysmyelination in an Ischemic Mouse Model of Periventricular Leukomalacia

2011 ◽  
Vol 31 (10) ◽  
pp. 2009-2018 ◽  
Author(s):  
Ali Fatemi ◽  
Mary Ann Wilson ◽  
Andre W Phillips ◽  
Michael T McMahon ◽  
Jiangyang Zhang ◽  
...  
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Mouse Model ◽  
Magnetization Transfer ◽  
Periventricular Leukomalacia ◽  
Internal Capsule ◽  
Artery Ligation ◽  
Magnetization Transfer Mri ◽  
The Right

Periventricular leukomalacia, PVL, is the leading cause of cerebral palsy in prematurely born infants, and therefore more effective interventions are required. The objective of this study was to develop an ischemic injury model of PVL in mice and to determine the feasibility of in vivo magnetization transfer (MT) magnetic resonance imaging (MRI) as a potential monitoring tool for the evaluation of disease severity and experimental therapeutics. Neonatal CD-1 mice underwent unilateral carotid artery ligation on postnatal day 5 (P5); at P60, in vivo T2-weighted (T2w) and MT-MRI were performed and correlated with postmortem histopathology. In vivo T2w MRI showed thinning of the right corpus callosum, but no significant changes in hippocampal and hemispheric volumes. Magnetization transfer MRI revealed significant white matter abnormalities in the bilateral corpus callosum and internal capsule. These quantitative MT-MRI changes correlated highly with postmortem findings of reduced myelin basic protein in bilateral white matter tracts. Ventriculomegaly and persistent astrogliosis were observed on the ligated side, along with evidence of axonopathy and fewer oligodendrocytes in the corpus callosum. We present an ischemia-induced mouse model of PVL, which has pathologic abnormalities resembling autopsy reports in infants with PVL. We further validate in vivo MRI techniques as quantitative monitoring tools that highly correlate with postmortem histopathology.

scholarly journals HOW ARE CARDIAC FUNCTIONS ALTERED IN PEDIATRIC PATIENTS RECEIVING ORAL IRON SUPPLEMENTATION DUE TO ANEMIA?

2021 ◽  
pp. 81-92
Author(s):  
Merve HİÇYILMAZ ◽  
Ayhan PEKTAŞ ◽  
Selçuk GÜREL ◽  
Mehmet Bilgehan PEKTAŞ
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Structural Difference ◽  
Internal Capsule ◽  
Control Group ◽  
Posterior Limb ◽  
Brain Functions ◽  
Significant Difference ◽  
Strongly Connected ◽  
The Right

Migraine is a multifactorial neurovascular syndrome characterized by typical headache attacks that occur with internal and external triggering factors in individuals with genetic susceptibility. It affects more than 12% of the general population. The aim of the present study is to compare the morphometric measurements of the determined white matter structures with the control group to investigate whether there is a structural difference in white matter structures in female patients with migraine. The width of the internal capsule parts (anterior limb, posterior limb and genu) and genu angle was evaluated through MRI. Corpus callosum related measurements were determined in the sagittal section. It was manually traced following its edge on the midsagittal slice of T1 images, where its structure appeared most remarkable. The right and left internal capsule related measurements were compared with migraine and control groups. Except the genu angle, there were statistically significant difference between all measurements and widths in the migraine group were greater than controls. No significant difference was found between the corpus callosum related measurements in the comparison of both groups. Internal capsule consists of several essential white matter fiber bundles of the brain, and is strongly connected between a range of cortical and subcortical anatomical structures. It has a crucial importance for brain functions and it can be affected by a variety of pathologies. The corpus callosum is the main fiber tract connecting two hemispheres with extensive connections and is topographically organized. It has been investigated in several neurodegenerative diseases as a marker for cortical pathology. Knowing the white matter structure in migraine patients, determining its prevalence, and its correlation with the severity, type and duration of migraine can give an idea to clinicians.

scholarly journals More Highly Myelinated White Matter Tracts are Associated with Faster Processing Speed in Healthy Adults

2017 ◽  
Author(s):  
Sidhant Chopra ◽  
Marnie Shaw ◽  
Thomas Shaw ◽  
Perminder S Sachdev ◽  
Kaarin J Anstey ◽  
...  
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Processing Speed ◽  
Middle Age ◽  
Principal Component ◽  
Internal Capsule ◽  
White Matter Tracts ◽  
Healthy Older Adults ◽  
Corona Radiata

AbstractThe objective of this study was to investigate whether the myelin content of white matter tracts is predictive of cogni–tive processing speed and whether such associations are modulated by age. Associations between myelin content and processing speed was assessed in 570 community-living individuals (277 middle-age, 293 older-age). Myelin content was measured using the mean T1w/T2w magnetic resonance ratio, in six white matter tracts (anterior corona radiata, superior corona radiata, pontine crossing tract, anterior limb of the internal capsule, genu of the corpus callosum, and splenium of the corpus callosum). Processing speed was estimated by extracting a principal component from 5 sep–arate tests of processing speed. It was found that myelin content of the bilateral anterior limb of the internal capsule and left splenium of the corpus callosum were significant predictors of processing speed, even after controlling for socio-demographic, health and genetic variables and correcting for multiple comparisons. A 1 SD increase in the myelin content of the anterior limb of the internal capsule was associated with 2.53% increase in processing speed and within the left splenium of the corpus callosum with a 2.20% increase in processing speed. In addition, significant differences in myelin content between middle-age and older participants were found in all six white matter tracts. The present results indicate that myelin content, estimated in vivo using a neuroimaging approach in healthy older adults is sufficiently precise to predict variability in processing speed in behavioural measures.

P02 - 361 White matter microstructural abnormalities in antisocial personality disorder: A pilot diffusion tensor imaging study

2011 ◽  
Vol 26 (S2) ◽  
pp. 957-957
Author(s):  
F. Sundram ◽  
Q. Deeley ◽  
S. Sarkar ◽  
E. Daly ◽  
R. Latham ◽  
...  
Keyword(s):  
Diffusion Tensor Imaging ◽  
White Matter ◽  
Personality Disorder ◽  
Corpus Callosum ◽  
Antisocial Personality Disorder ◽  
Diffusion Tensor ◽  
Internal Capsule ◽  
Uncinate Fasciculus ◽  
Antisocial Personality ◽  
The Right

IntroductionAntisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about white matter (WM) abnormalities in tracts linking grey matter regions. A previous diffusion tensor imaging (DT-MRI) tractography study in ASPD and psychopathy revealed abnormalities in the right uncinate fasciculus, indicating fronto-limbic disconnectivity.ObjectivesIt is not clear whether WM abnormalities are restricted to only this tract or are more widespread. Therefore, we planned to use whole brain DT-MRI voxel-based analyses.AimsTo clarify if WM abnormalities extend beyond the frontal lobe.MethodsWe used whole brain DT-MRI to compare WM fractional anisotropy (FA) of 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects, we related differences in FA to severity of psychopathy measures.ResultsSignificant WM FA reductions were found in ASPD subjects relative to controls. These were found bilaterally in the anterior corpus callosum. Right hemisphere FA reduction was found in the anterior corona radiata, uncinate fasciculus, inferior fronto-occipital fasciculus and internal capsule. Left hemisphere, FA deficits encompassed the inferior longitudinal fasciculus, inferior fronto-occipital fasciculus and internal capsule. There was a significant negative correlation between WM FA in the right uncinate fasciculus and corpus callosum and measures of psychopathy.ConclusionsWe report FA reduction in the uncinate fasciculus and anterior corpus callosum which may be associated with frontal and inter-hemispheric disconnectivity in ASPD, in addition to abnormalities in other tracts which directly or indirectly connect to prefrontal regions.

scholarly journals MORPHOMETRIC ANALYSIS OF THE WHITE MATTER STRUCTURES IN FEMALE MIGRAINE PATIENTS

2021 ◽  
pp. 71-79
Author(s):  
Ozan TURAMANLAR ◽  
Hilal GÜZEL ◽  
Hayri DEMİRBAŞ ◽  
Furkan KAYA ◽  
Abdülkadir BİLİR ◽  
...  
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Structural Difference ◽  
Internal Capsule ◽  
Control Group ◽  
Posterior Limb ◽  
Brain Functions ◽  
Significant Difference ◽  
Strongly Connected ◽  
The Right

Migraine is a multifactorial neurovascular syndrome characterized by typical headache attacks that occur with internal and external triggering factors in individuals with genetic susceptibility. It affects more than 12% of the general population. The aim of the present study is to compare the morphometric measurements of the determined white matter structures with the control group to investigate whether there is a structural difference in white matter structures in female patients with migraine. The width of the internal capsule parts (anterior limb, posterior limb and genu) and genu angle was evaluated through MRI. Corpus callosum related measurements were determined in the sagittal section. It was manually traced following its edge on the midsagittal slice of T1 images, where its structure appeared most remarkable. The right and left internal capsule related measurements were compared with migraine and control groups. Except the genu angle, there were statistically significant difference between all measurements and widths in the migraine group were greater than controls. No significant difference was found between the corpus callosum related measurements in the comparison of both groups. Internal capsule consists of several essential white matter fiber bundles of the brain, and is strongly connected between a range of cortical and subcortical anatomical structures. It has a crucial importance for brain functions and it can be affected by a variety of pathologies. The corpus callosum is the main fiber tract connecting two hemispheres with extensive connections and is topographically organized. It has been investigated in several neurodegenerative diseases as a marker for cortical pathology. Knowing the white matter structure in migraine patients, determining its prevalence, and its correlation with the severity, type and duration of migraine can give an idea to clinicians.

Changes in mild cognitive impairment and its subtypes as seen on diffusion tensor imaging

2012 ◽  
Vol 24 (9) ◽  
pp. 1483-1493 ◽  
Author(s):  
Senthil Thillainadesan ◽  
Wei Wen ◽  
Lin Zhuang ◽  
John Crawford ◽  
Nicole Kochan ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
White Matter ◽  
Multiple Testing ◽  
Diffusion Tensor ◽  
Internal Capsule ◽  
Anterior Cingulate ◽  
Corona Radiata ◽  
Amnestic Mci ◽  
Subcortical Regions ◽  
The Right

ABSTRACTBackground: Previous studies using diffusion tensor imaging (DTI) have observed microstructural abnormalities in white matter regions in both Alzheimer's disease and mild cognitive impairment (MCI). The aim of this work was to examine the abnormalities in white matter and subcortical regions of MCI and its subtypes in a large, community-dwelling older aged cohortMethods: A community-based sample of 396 individuals without dementia underwent medical assessment, neuropsychiatric testing, and neuroimaging. Of these, 158 subjects were classified as MCI and 238 as cognitively normal (controls) based on international MCI consensus criteria. Regional fractional anisotropy (FA) and mean diffusivity (MD) measures were calculated from the DTI and compared between groups. The false discovery rate correction was applied for multiple testing.Results: Subjects with MCI did not have significant differences in FA compared with controls after correction for multiple testing, but had increased MD in the right putamen, right anterior limb of the internal capsule, genu and splenium of the corpus callosum, right posterior cingulate gyrus, left superior frontal gyrus, and right and left corona radiata. When compared with controls, changes in left anterior cingulate, left superior frontal gyrus, and right corona radiata were associated with amnestic MCI (aMCI), whereas changes in the right putamen, right anterior limb of the internal capsule, and the right corona radiata were associated with non-amnestic MCI (naMCI). On logistic regression, the FA values in the left superior gyrus and MD values in the anterior cingulate distinguished aMCI from naMCI.Conclusions: MCI is associated with changes in white matter and subcortical regions as seen on DTI. Changes in some anterior brain regions distinguish aMCI from naMCI.

scholarly journals A higher proportion of ermin-immunopositive oligodendrocytes in areas of remyelination

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256155
Author(s):  
Intakhar Ahmad ◽  
Stig Wergeland ◽  
Eystein Oveland ◽  
Lars Bø
Keyword(s):  
Multiple Sclerosis ◽  
White Matter ◽  
Corpus Callosum ◽  
Mouse Model ◽  
Grey Matter ◽  
Early Stage ◽  
Relative Proportion ◽  
Normal Appearing White Matter ◽  
The Brain

Incomplete remyelination is frequent in multiple sclerosis (MS)-lesions, but there is no established marker for recent remyelination. We investigated the role of the oligodendrocyte/myelin protein ermin in de- and remyelination in the cuprizone (CPZ) mouse model, and in MS. The density of ermin+ oligodendrocytes in the brain was significantly decreased after one week of CPZ exposure (p < 0.02). The relative proportion of ermin+ cells compared to cells positive for the late-stage oligodendrocyte marker Nogo-A increased at the onset of remyelination in the corpus callosum (p < 0.02). The density of ermin-positive cells increased in the corpus callosum during the CPZ-phase of extensive remyelination (p < 0.0001). In MS, the density of ermin+ cells was higher in remyelinated lesion areas compared to non-remyelinated areas both in white- (p < 0.0001) and grey matter (p < 0.0001) and compared to normal-appearing white matter (p < 0.001). Ermin immunopositive cells in MS-lesions were not immunopositive for the early-stage oligodendrocyte markers O4 and O1, but a subpopulation was immunopositive for Nogo-A. The data suggest a relatively higher proportion of ermin immunopositivity in oligodendrocytes compared to Nogo-A indicates recent or ongoing remyelination.

scholarly journals Consistent altered internal capsule white matter microstructure in insomnia disorder

SLEEP ◽  
2020 ◽  
Vol 43 (8) ◽  
Author(s):  
Tom Bresser ◽  
Jessica C Foster-Dingley ◽  
Rick Wassing ◽  
Jeanne Leerssen ◽  
Jennifer R Ramautar ◽  
...  
Keyword(s):  
White Matter ◽  
Internal Capsule ◽  
Mixed Effect ◽  
Significant Group ◽  
Consistent Finding ◽  
White Matter Microstructure ◽  
Insomnia Disorder ◽  
Underlying Mechanisms ◽  
The Right ◽  
Insomnia Severity

Abstract Study Objectives Suggested neural correlates of insomnia disorder have been hard to replicate. Even the most consistent finding, altered white matter microstructure in the anterior limb of the internal capsule, is based on handful studies. The urge for replicable targets to understand the underlying mechanisms of insomnia made us study white matter fractional anisotropy (FA) across three samples of cases and controls. Methods 3-Tesla MRI diffusion tensor imaging data of three independent samples were combined for analysis, resulting in n = 137 participants, of whom 73 were diagnosed with insomnia disorder and 64 were matched controls without sleep complaints. Insomnia severity was measured with the Insomnia Severity Index (ISI). White matter microstructure was assessed with FA. White matter tracts were skeletonized and analyzed using tract-based spatial statistics. We performed a region-of-interest analysis using linear mixed-effect models to evaluate case–control differences in internal capsule FA as well as associations between internal capsule FA and insomnia severity. Results FA in the right limb of the anterior internal capsule was lower in insomnia disorder than in controls (β = −9.76e−3; SE = 4.17e−3, p = .034). In the entire sample, a higher ISI score was associated with a lower FA value of the right internal capsule (β = −8.05e− 4 FA/ISI point, SE = 2.60e− 4, p = .008). Ancillary whole brain voxel-wise analyses showed no significant group difference or association with insomnia severity after correction for multiple comparisons. Conclusions The internal capsule shows small but consistent insomnia-related alterations. The findings support a circuit-based approach to underlying mechanisms since this tract connects many brain areas previously implicated in insomnia.

scholarly journals Combining Hypothermia and Oleuropein Subacutely Protects Subcortical White Matter in a Swine Model of Neonatal Hypoxic-Ischemic Encephalopathy

2020 ◽  
Author(s):  
Jennifer K Lee ◽  
Polan T Santos ◽  
May W Chen ◽  
Caitlin E O’Brien ◽  
Ewa Kulikowicz ◽  
...  
Keyword(s):  
White Matter ◽  
Motor Cortex ◽  
Corpus Callosum ◽  
Internal Capsule ◽  
Subcortical White Matter ◽  
White Matter Injury ◽  
Swine Model ◽  
Cortex Neuron ◽  
Motor Cortex Neuron ◽  
Ischemic Encephalopathy

Abstract Neonatal hypoxia-ischemia (HI) causes white matter injury that is not fully prevented by therapeutic hypothermia. Adjuvant treatments are needed. We compared myelination in different piglet white matter regions. We then tested whether oleuropein (OLE) improves neuroprotection in 2- to 4-day-old piglets randomized to undergo HI or sham procedure and OLE or vehicle administration beginning at 15 minutes. All groups received overnight hypothermia and rewarming. Injury in the subcortical white matter, corpus callosum, internal capsule, putamen, and motor cortex gray matter was assessed 1 day later. At baseline, piglets had greater subcortical myelination than in corpus callosum. Hypothermic HI piglets had scant injury in putamen and cerebral cortex. However, hypothermia alone did not prevent the loss of subcortical myelinating oligodendrocytes or the reduction in subcortical myelin density after HI. Combining OLE with hypothermia improved post-HI subcortical white matter protection by preserving myelinating oligodendrocytes, myelin density, and oligodendrocyte markers. Corpus callosum and internal capsule showed little HI injury after hypothermia, and OLE accordingly had minimal effect. OLE did not affect putamen or motor cortex neuron counts. Thus, OLE combined with hypothermia protected subcortical white matter after HI. As an adjuvant to hypothermia, OLE may subacutely improve regional white matter protection after HI.

scholarly journals High-resolution in vivo imaging of human locus coeruleus by magnetization transfer MRI at 3T and 7T

NeuroImage ◽  
2018 ◽  
Vol 168 ◽  
pp. 427-436 ◽  
Author(s):  
Nikos Priovoulos ◽  
Heidi I.L. Jacobs ◽  
Dimo Ivanov ◽  
Kâmil Uludağ ◽  
Frans R.J. Verhey ◽  
...  
Keyword(s):  
High Resolution ◽  
Locus Coeruleus ◽  
In Vivo Imaging ◽  
Magnetization Transfer ◽  
Magnetization Transfer Mri

Corpus Callosum Measurement as an in Vivo Indicator for Neocortical Neuronal Integrity, but not White Matter Pathology, in Alzheimer's Disease

2000 ◽  
Vol 903 (1 VASCULAR FACT) ◽  
pp. 470-476 ◽  
Author(s):  
HARALD HAMPEL ◽  
STEFAN J. TEIPEL ◽  
GENE E. ALEXANDER ◽  
BARRY HORWITZ ◽  
PIETRO PIETRINI ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
White Matter ◽  
Corpus Callosum ◽  
White Matter Pathology
Sign in / Sign up

Export Citation Format

Share Document