Reorganizations of latency structure within white matter from wakefulness to sleep

AbstractPrevious studies based on resting-state fMRI (rsfMRI) data have revealed the existence of highly reproducible latency structure, reflecting the propagation of BOLD fMRI signals, in white matter (WM). Here, based on simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data collected from 35 healthy subjects who were instructed to sleep, we explored the alterations of propagations in WM across wakefulness and nonrapid eye movement (NREM) sleep stages. Lagged cross-covariance was computed among voxel-wise time series, followed by parabolic interpolation to determine the actual latency value in-between. In WM, regions including cerebellar peduncle, internal capsule, posterior thalamic radiation, genu of corpus callosum, and corona radiata, were found to change their temporal roles drastically, as revealed by applying linear mixed-effect model on voxel-wise latency projections across wakefulness and NREM sleep stages. Using these regions as seeds, further seed-based latency analysis revealed that variations of latency projections across different stages were underlain by inconsistent temporal shifts between each seed and the remaining part of WM. Finally, latency analysis on resting-state networks (RSNs), obtained by applying k-means clustering technique on group-level functional connectivity matrix, identified a path of signal propagations similar to previous findings in EEG during wakefulness, which propagated mainly from the brainstem upward to internal capsule and further to corona radiata. This path showed inter-RSN temporal reorganizations depending on the paired stages between which the brain transitioned, e.g., it changed, between internal capsule and corona radiata, from mainly unidirectional to clearly reciprocal when the brain transitioned from wakefulness to N3 stage. These findings suggested the functional role of BOLD signals in white matter as a slow process, dynamically modulated across wakefulness and NREM sleep stages, and involving in maintaining different levels of consciousness and cognitive processes.

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

International Psychogeriatrics ◽

10.1017/s1041610212000270 ◽

2012 ◽

Vol 24 (9) ◽

pp. 1483-1493 ◽

Cited By ~ 12

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.

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Consistent altered internal capsule white matter microstructure in insomnia disorder

SLEEP ◽

10.1093/sleep/zsaa031 ◽

2020 ◽

Vol 43 (8) ◽

Cited By ~ 3

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.

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Microsurgical anatomy of the central core of the brain

Journal of Neurosurgery ◽

10.3171/2017.5.jns162897 ◽

2018 ◽

Vol 129 (3) ◽

pp. 752-769 ◽

Cited By ~ 13

Author(s):

Eduardo Carvalhal Ribas ◽

Kaan Yağmurlu ◽

Evandro de Oliveira ◽

Guilherme Carvalhal Ribas ◽

Albert Rhoton

Keyword(s):

White Matter ◽

Caudate Nucleus ◽

Internal Capsule ◽

Central Core ◽

Surgical Approaches ◽

Microsurgical Anatomy ◽

Functional Importance ◽

Posterior Portion ◽

External Capsule ◽

The Brain

OBJECTIVEThe purpose of this study was to describe in detail the cortical and subcortical anatomy of the central core of the brain, defining its limits, with particular attention to the topography and relationships of the thalamus, basal ganglia, and related white matter pathways and vessels.METHODSThe authors studied 19 cerebral hemispheres. The vascular systems of all of the specimens were injected with colored silicone, and the specimens were then frozen for at least 1 month to facilitate identification of individual fiber tracts. The dissections were performed in a stepwise manner, locating each gray matter nucleus and white matter pathway at different depths inside the central core. The course of fiber pathways was also noted in relation to the insular limiting sulci.RESULTSThe insular surface is the most superficial aspect of the central core and is divided by a central sulcus into an anterior portion, usually containing 3 short gyri, and a posterior portion, with 2 long gyri. It is bounded by the anterior limiting sulcus, the superior limiting sulcus, and the inferior limiting sulcus. The extreme capsule is directly underneath the insular surface and is composed of short association fibers that extend toward all the opercula. The claustrum lies deep to the extreme capsule, and the external capsule is found medial to it. Three fiber pathways contribute to form both the extreme and external capsules, and they lie in a sequential anteroposterior disposition: the uncinate fascicle, the inferior fronto-occipital fascicle, and claustrocortical fibers. The putamen and the globus pallidus are between the external capsule, laterally, and the internal capsule, medially. The internal capsule is present medial to almost all insular limiting sulci and most of the insular surface, but not to their most anteroinferior portions. This anteroinferior portion of the central core has a more complex anatomy and is distinguished in this paper as the “anterior perforated substance region.” The caudate nucleus and thalamus lie medial to the internal capsule, as the most medial structures of the central core. While the anterior half of the central core is related to the head of the caudate nucleus, the posterior half is related to the thalamus, and hence to each associated portion of the internal capsule between these structures and the insular surface. The central core stands on top of the brainstem. The brainstem and central core are connected by several white matter pathways and are not separated from each other by any natural division. The authors propose a subdivision of the central core into quadrants and describe each in detail. The functional importance of each structure is highlighted, and surgical approaches are suggested for each quadrant of the central core.CONCLUSIONSAs a general rule, the internal capsule and its vascularization should be seen as a parasagittal barrier with great functional importance. This is of particular importance in choosing surgical approaches within this region.

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White Matter Dysconnectivity in Panic Disorder with Early Sexual Abuse History: A Preliminary Study

Klinička psihologija ◽

10.21465/2016-kp-p-0002 ◽

2016 ◽

Vol 9 (1) ◽

pp. 128-128

Author(s):

S. Yu ◽

◽

S. Lee

Keyword(s):

Sexual Abuse ◽

White Matter ◽

Panic Disorder ◽

Childhood Abuse ◽

Internal Capsule ◽

Sensitivity Index ◽

Abuse History ◽

Brain White Matter ◽

Preliminary Study ◽

The Brain

Objective: People who have experienced childhood abuse are more likely to experience frequent or generalized anxiety or panic disorder (PD). Although previous studies have used magnetic resonance imaging (MRI) to demonstrate structural abnormalities of brain in subjects with PD, there are no study about the brain white matter (WM) connectivity differences between PD with and without early sexual abuse. The objective of this study is to compare the brain WM connectivity between PD with and without early sexual abuse history. Design and Method: Twelve right-handed patients with PD [12 women; 35.91±10.29 (mean±SD) age] who met the diagnostic criteria in Structured Clinical Interview for DSM-IV were examined by means of MRI at 3 Tesla. We divided the patients with PD into two groups with and without early sexual abuse to compare the WM connectivity. Panic Disorder Severity Scale (PDSS), Beck Depression Inventory (BDI) and Anxiety Sensitivity Index-Revised (ASI-R) were administered in PD patients. Results: Tract-based spatial statistics showed that fractional anisotropy (FA) values in PD with sexual abuse history were significantly higher than PD without abuse in the right internal capsule, superior corona radiata, sagittal stratum, fornix. The scores of PDSS, BDI, ASI-R were significantly correlated in the above-mentioned WM regions. Conclusions: This preliminary study suggests that early sexual abuse could influence the connectivity among emotion related limbic structures in PD.

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Patients With Chronic Migraine Without History of Medication Overuse Are Characterized by a Peculiar White Matter Fiber Bundle Profile

10.21203/rs.3.rs-33717/v1 ◽

2020 ◽

Author(s):

Gianluca Coppola ◽

Antonio Di Renzo ◽

Emanuele Tinelli ◽

Barbara Petolicchio ◽

Cherubino Di Lorenzo ◽

...

Keyword(s):

White Matter ◽

Chronic Migraine ◽

Diffusion Tensor ◽

Internal Capsule ◽

Posterior Limb ◽

History Of ◽

The Right ◽

Normal White Matter ◽

Microstructural Integrity ◽

The Brain

Abstract Background: We investigated intracerebral fiber bundles using a tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) datato investigate microstructural integrity in patients with episodic (MO) and chronic migraine (CM).Methods: We performed DTI in 19 patients with MO within interictal periods, 18 patients with CM without any history of drug abuse, and 18 healthy controls (HCs) using a 3T magnetic resonance imaging scanner. We calculated diffusion metrics, including fractional anisotropy (FA), axial diffusion (AD), radial diffusion (RD), and mean diffusion (MD).Results: TBSS revealed no significant differences in the FA, MD, RD, and AD maps between the MO and HC groups. In comparison to the HC group, theCM group exhibited widespread increased RD (bilateral superior [SCR] and posterior corona radiata [PCR], bilateral genu of the corpus callosum [CC], bilateral posterior limb of internal capsule [IC], bilateral superior longitudinal fasciculus [LF]) and MD values (tracts of the right SCR and PCR, right superior LF, and right splenium of the CC). In comparison to theMO group, theCM group showed decreased FA (bilateral SCR and PCR, bilateral body of CC, right superior LF, right forceps minor) and increased MD values (bilateral SCR and right PCR, right body of CC, right superior LF, right splenium of CC, and right posterior limb of IC). Conclusion: Our results suggest that chronic migraine can be associated withthe widespread disruption of normal white matter integrity in the brain.

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MRI and MRV features of a patient with Heat Stroke: a case report

10.21203/rs.2.1866/v1 ◽

2019 ◽

Author(s):

Lizhi Cao ◽

Juan Wang ◽

Yaxuan Gao ◽

Yumei Liang ◽

Jinhua Yan ◽

...

Keyword(s):

White Matter ◽

Magnetic Resonance ◽

Venous Thrombosis ◽

Cerebral Venous Thrombosis ◽

Heat Stroke ◽

Internal Capsule ◽

Subcortical White Matter ◽

Posterior Limb ◽

External Capsule ◽

The Brain

Abstract Background Heat stroke (HS) is a critical illness that can cause multiple organ dysfunction including damage to the central nervous system (CNS), which can be life-threatening in severe cases. The brain image lesions of HS patient with CNS damage has been rarely reported before and usually variable in different cases, causing confusing to doctors when encounter these patients in the clinic. Cerebral venous thrombosis (CVT) is a rare cause of stroke that mostly affects young people and children. The pathogenesis of brain damage caused by HS is complex, CVT may be involved in the pathogenesis of HS with CNS damage. In this manuscript, we report a case of HS with CVT with symmetrical lesions in the bilateral putamen,posterior limb of internal capsule,external capsule, insula lobe, and subcortical white matter inside the brain. Case presentation We introduced a 48-year-old man who suffered from HS in the hot summer. At the time of admission, he showed high body temperature, coma and shock. Later, he had laboratory evidence of rhabdomyolysis syndrome, acute kidney and liver damage, electrolyte imbalance, acid-base balance disorders, and high D-dimer levels. After several days of anti-shock treatment, his level of consciousness has improved but his vision has declined. The cerebral magnetic resonance imaging (MRI) showed symmetrical lesions of the bilateral posterior limb of internal capsule,putamen,external capsule and insula, and subcortical white matter, and cerebral magnetic resonance venography (MRV) showed the formation of deep cerebral venous thrombosis (DCVT). Therefore, the anti-coagulation treatment was given to patient. After timely clinical intervention, the symptom of the patient was gradually improved. Conclusions The case shows that HS can cause CVT. Therefore, we believe that when we need to identify the cerebral MRI findings of HS, early MRV can greatly help the diagnosis of the disease, and can effectively improve the prognosis.

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Functional connectivity and microstructural changes of the brain in primary Sjögren syndrome: the relationship with depression

Acta Radiologica ◽

10.1177/0284185120909982 ◽

2020 ◽

Vol 61 (12) ◽

pp. 1684-1694

Author(s):

Artemis Andrianopoulou ◽

Anastasia K Zikou ◽

Loukas G Astrakas ◽

Nafsika Gerolymatou ◽

Vasileios Xydis ◽

...

Keyword(s):

White Matter ◽

Functional Connectivity ◽

Resting State ◽

Pulse Sequence ◽

Sjogren Syndrome ◽

White Matter Tracts ◽

Microstructural Changes ◽

Primary Sjögren Syndrome ◽

The Relationship ◽

The Brain

Background Fatigue and depression are among the most common manifestations of primary Sjögren syndrome (pSS), but information is lacking on the relationship with brain function and microstructural changes. Purpose To investigate microstructural changes and brain connectivity in pSS, and to evaluate their relationship with fatigue and depression. Material and Methods The study included 29 patients with pSS (mean age 61.2 ± 12.1 years; disease duration 10.5 ± 5.9 years) and 28 controls (mean age 58.4 ± 9.2 years). All the patients completed the Beck’s depression and Fatigue Assessment Scale questionnaires. The imaging protocol consisted of: (i) standard magnetic resonance imaging (MRI) pulse sequences (FLAIR, 3D T1W); (ii) a diffusion tensor imaging pulse sequence; and (iii) a resting state functional MRI pulse sequence. Resting state brain networks and maps of diffusion metrics were calculated and compared between patients and controls. Results Compared with the controls, the patients with pSS and depression showed increased axial, radial, and mean diffusivity and decreased fractional anisotropy; those without depression showed decreased axial diffusivity in major white matter tracts (superior longitudinal fasciculus, inferior longitudinal fasciculus, corticospinal tract, anterior thalamic radiation, inferior fronto-occipital fasciculus, cingulum, uncinate fasciculus, and forceps minor-major). Decreased brain activation in the sensorimotor network was observed in the patients with pSS compared with the controls. No correlation was found between fatigue and structural or functional changes of the brain. Conclusion pSS is associated with functional connectivity abnormalities of the somatosensory cortex and microstructural abnormalities in major white matter tracts, which are more pronounced in depression.

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White Matter-Governed Superior Frontal Sulcus Surgical Paradigm: A Radioanatomic Microsurgical Study—Part I

Operative Neurosurgery ◽

10.1093/ons/opaa065 ◽

2020 ◽

Vol 19 (4) ◽

pp. E343-E356 ◽

Cited By ~ 2

Author(s):

Alejandro Monroy-Sosa ◽

Srikant S Chakravarthi ◽

Melanie B Fukui ◽

Bhavani Kura ◽

Jonathan E Jennings ◽

...

Keyword(s):

White Matter ◽

Diffusion Tensor ◽

Internal Capsule ◽

Entry Point ◽

Coronal Suture ◽

Corona Radiata ◽

Cingulum Bundle ◽

Sagittal Sinus ◽

Precentral Sulcus ◽

Superior Frontal Sulcus

Abstract BACKGROUND Frontal subcortical and intraventricular pathologies are traditionally accessed via transcortical or interhemispheric-transcallosal corridors. OBJECTIVE To describe the microsurgical subcortical anatomy of the superior frontal sulcus (SFS) corridor. METHODS Cadaveric dissections were undertaken and correlated with magnetic resonance imaging/diffusion-tensor imaging-Tractography. Surgical cases demonstrated clinical applicability. RESULTS SFS was divided into the following divisions: proximal, precentral sulcus to coronal suture; middle, 3-cm anterior to coronal suture; and distal, middle division to the orbital crest. Anatomy was organized as layered circumferential rings projecting radially towards the ventricles: (1) outer ring: at the level of the SFS, the following lengths were measured: (A) precentral sulcus to coronal suture = 2.29 cm, (B) frontal bone projection of superior sagittal sinus (SSS) to SFS = 2.37 cm, (C) superior temporal line to SFS = 3.0 cm, and (D) orbital crest to distal part of SFS = 2.32 cm; and (2) inner ring: (a) medial to SFS, U-fibers, frontal aslant tract (FAT), superior longitudinal fasciculus I (SLF-I), and cingulum bundle, (b) lateral to SFS, U-fibers, (SLF-II), claustrocortical fibers (CCF), and inferior fronto-occipital fasciculus, and (c) intervening fibers, FAT, corona radiata, and CCF. The preferred SFS parafascicular entry point (SFSP-EP) also referred to as the Kassam-Monroy entry point (KM-EP) bisects the distance between the midpupillary line and the SSS and has the following coordinates: x = 2.3 cm (lateral to SSS), y ≥ 3.5 cm (anterior to CS), and z = parallel corona radiata and anterior limb of the internal capsule. CONCLUSION SFS corridor can be divided into lateral, medial, and intervening white matter tract segments. Based on morphometric assessment, the optimal SFSP-EP is y ≥ 3.5 cm, x = 2.3 cm, and z = parallel to corona radiata and anterior limb of the internal capsule.

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MRI and MRV features of a patient with Heat Stroke: a case report

10.21203/rs.2.1866/v2 ◽

2019 ◽

Author(s):

Lizhi Cao ◽

Juan Wang ◽

Yaxuan Gao ◽

Yumei Liang ◽

Jinhua Yan ◽

...

Keyword(s):

White Matter ◽

Magnetic Resonance ◽

Venous Thrombosis ◽

Cerebral Venous Thrombosis ◽

Heat Stroke ◽

Internal Capsule ◽

Subcortical White Matter ◽

Posterior Limb ◽

External Capsule ◽

The Brain

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Patients with chronic migraine without history of medication overuse are characterized by a peculiar white matter fiber bundle profile

10.21203/rs.3.rs-33717/v2 ◽

2020 ◽

Author(s):

Gianluca Coppola ◽

Antonio Di Renzo ◽

Emanuele Tinelli ◽

Barbara Petolicchio ◽

Cherubino Di Lorenzo ◽

...

Keyword(s):

White Matter ◽

Chronic Migraine ◽

Diffusion Tensor ◽

Internal Capsule ◽

Posterior Limb ◽

History Of ◽

The Right ◽

Normal White Matter ◽

Microstructural Integrity ◽

The Brain

Abstract Background: We investigated intracerebral fiber bundles using a tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) data to investigate microstructural integrity in patients with episodic (MO) and chronic migraine (CM).Methods: We performed DTI in 19 patients with MO within interictal periods, 18 patients with CM without any history of drug abuse, and 18 healthy controls (HCs) using a 3T magnetic resonance imaging scanner. We calculated diffusion metrics, including fractional anisotropy (FA), axial diffusion (AD), radial diffusion (RD), and mean diffusion (MD).Results: TBSS revealed no significant differences in the FA, MD, RD, and AD maps between the MO and HC groups. In comparison to the HC group, the CM group exhibited widespread increased RD (bilateral superior [SCR] and posterior corona radiata [PCR], bilateral genu of the corpus callosum [CC], bilateral posterior limb of internal capsule [IC], bilateral superior longitudinal fasciculus [LF]) and MD values (tracts of the right SCR and PCR, right superior LF, and right splenium of the CC). In comparison to the MO group, the CM group showed decreased FA (bilateral SCR and PCR, bilateral body of CC, right superior LF, right forceps minor) and increased MD values (bilateral SCR and right PCR, right body of CC, right superior LF, right splenium of CC, and right posterior limb of IC). Conclusion: Our results suggest that chronic migraine can be associated with the widespread disruption of normal white matter integrity in the brain.

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