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

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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MRI substrates of sustained attention system and cognitive impairment in pediatric MS patients

Neurology ◽

10.1212/wnl.0000000000004388 ◽

2017 ◽

Vol 89 (12) ◽

pp. 1265-1273 ◽

Cited By ~ 4

Author(s):

Ermelinda De Meo ◽

Lucia Moiola ◽

Angelo Ghezzi ◽

Pierangelo Veggiotti ◽

Ruggero Capra ◽

...

Keyword(s):

Cognitive Impairment ◽

White Matter ◽

Sustained Attention ◽

Structural Damage ◽

Performance Test ◽

Diffusion Tensor ◽

Group Analysis ◽

Anterior Cingulate ◽

Attention Network ◽

Attention System

Objective:To explore the structural and functional integrity of the sustained attention system in patients with pediatric multiple sclerosis (MS) and its effect on cognitive impairment.Methods:We enrolled 57 patients with pediatric MS and 14 age- and sex-matched healthy controls (HCs). Patients with >3 abnormal tests at neuropsychological evaluation were classified as cognitively impaired (CI). Sustained attention system activity was studied with fMRI during the Conners Continuous Performance Test (CCPT). Structural integrity of attention network connections was quantified with diffusion tensor (DT) MRI.Results:Within-group analysis showed similar patterns of recruitment of the attention network in HCs and patients with pediatric MS. Diffuse network DT MRI structural abnormalities were found in patients with MS. During CCPT, with increasing task demand, patients with pediatric MS showed increased activation of the left thalamus, anterior insula, and anterior cingulate cortex (ACC) and decreased recruitment of the right precuneus compared to HCs. Thirteen patients (23%) were classified as CI. Compared to cognitively preserved patients, CI patients with pediatric MS had decreased recruitment of several areas located mainly in parietal and occipital lobes and cerebellum and increased deactivation of the ACC, combined with more severe structural damage of white matter tracts connecting these regions.Conclusions:Our results suggest that the age-expected level of sustained attention system functional competence is achieved in patients with pediatric MS. Inefficient regulation of the functional interaction between different areas of this system, due to abnormal white matter integrity, may result in global cognitive impairment in these patients.

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Anatomy and white matter connections of the orbitofrontal gyrus

Journal of Neurosurgery ◽

10.3171/2017.3.jns162070 ◽

2018 ◽

Vol 128 (6) ◽

pp. 1865-1872 ◽

Cited By ~ 17

Author(s):

Joshua D. Burks ◽

Andrew K. Conner ◽

Phillip A. Bonney ◽

Chad A. Glenn ◽

Cordell M. Baker ◽

...

Keyword(s):

White Matter ◽

Diffusion Tensor ◽

Diffusion Imaging ◽

Internal Capsule ◽

Ground Truth ◽

Outcome Evaluation ◽

Anterior Cingulate ◽

Anatomical Dissection ◽

Visual Spatial ◽

Human Connectome Project

OBJECTIVEThe orbitofrontal cortex (OFC) is understood to have a role in outcome evaluation and risk assessment and is commonly involved with infiltrative tumors. A detailed understanding of the exact location and nature of associated white matter tracts could significantly improve postoperative morbidity related to declining capacity. Through diffusion tensor imaging–based fiber tracking validated by gross anatomical dissection as ground truth, the authors have characterized these connections based on relationships to other well-known structures.METHODSDiffusion imaging from the Human Connectome Project for 10 healthy adult controls was used for tractography analysis. The OFC was evaluated as a whole based on connectivity with other regions. All OFC tracts were mapped in both hemispheres, and a lateralization index was calculated with resultant tract volumes. Ten postmortem dissections were then performed using a modified Klingler technique to demonstrate the location of major tracts.RESULTSThe authors identified 3 major connections of the OFC: a bundle to the thalamus and anterior cingulate gyrus, passing inferior to the caudate and medial to the vertical fibers of the thalamic projections; a bundle to the brainstem, traveling lateral to the caudate and medial to the internal capsule; and radiations to the parietal and occipital lobes traveling with the inferior fronto-occipital fasciculus.CONCLUSIONSThe OFC is an important center for processing visual, spatial, and emotional information. Subtle differences in executive functioning following surgery for frontal lobe tumors may be better understood in the context of the fiber-bundle anatomy highlighted by this study.

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Cognitive deficits and white matter abnormalities in never-treated first-episode schizophrenia

Translational Psychiatry ◽

10.1038/s41398-020-01049-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mi Yang ◽

Shan Gao ◽

Xiangyang Zhang

Keyword(s):

Cognitive Impairment ◽

White Matter ◽

Diffusion Tensor ◽

Internal Capsule ◽

First Episode ◽

Control Group ◽

Pathophysiological Mechanism ◽

Healthy Controls ◽

Healthy Control ◽

First Episode Schizophrenia

Abstract Cognitive impairment is viewed as a core symptom of schizophrenia (SCZ), but its pathophysiological mechanism remains unclear. White matter (WM) disruption is considered to be a central abnormality that may contribute to cognitive impairment in SCZ patients. However, few studies have addressed the association between cognition and WM integrity in never-treated first-episode (NTFE) patients with SCZ. In this study, we used the MATRICS Consensus Cognitive Battery (MCCB) to evaluate cognitive function in NTFE patients (n = 39) and healthy controls (n = 30), and associated it with whole-brain fractional anisotropy (FA) values obtained via voxel-based diffusion tensor imaging. We found that FA was lower in five brain areas of SCZ patients, including the cingulate gyrus, internal capsule, corpus callosum, cerebellum, and brainstem. Compared with the healthy control group, the MCCB’s total score and 8 out of 10 subscores were significantly lower in NTFE patients (all p < 0.001). Moreover, in patients but not healthy controls, the performance in the Trail Making Test was negatively correlated with the FA value in the left cingulate. Our findings provide evidence that WM disconnection is involved in some cognitive impairment in the early course of SCZ.

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White-matter microstructure in previously drug-naive patients with schizophrenia after 6 weeks of treatment

Psychological Medicine ◽

10.1017/s0033291713000238 ◽

2013 ◽

Vol 43 (11) ◽

pp. 2301-2309 ◽

Cited By ~ 55

Author(s):

Q. Wang ◽

C. Cheung ◽

W. Deng ◽

M. Li ◽

C. Huang ◽

...

Keyword(s):

White Matter ◽

Early Phase ◽

Clinical Symptoms ◽

Diffusion Tensor ◽

Disease Process ◽

Anterior Cingulate ◽

First Episode ◽

Drug Naïve ◽

The Right ◽

First Episode Schizophrenia

BackgroundIt is not clear whether the progressive changes in brain microstructural deficits documented in previous longitudinal magnetic resonance imaging (MRI) studies might be due to the disease process or to other factors such as medication. It is important to explore the longitudinal alterations in white-matter (WM) microstructure in antipsychotic-naive patients with first-episode schizophrenia during the very early phase of treatment when relatively ‘free’ from chronicity.MethodThirty-five patients with first-episode schizophrenia and 22 healthy volunteers were recruited. High-resolution diffusion tensor imaging (DTI) was obtained from participants at baseline and after 6 weeks of treatment. A ‘difference map’ for each individual was calculated from the 6-week follow-up fractional anisotropy (FA) of DTI minus the baseline FA. Differences in Positive and Negative Syndrome Scale (PANSS) scores and Global Assessment of Functioning (GAF) scores between baseline and 6 weeks were also evaluated and expressed as a 6-week/baseline ratio.ResultsCompared to healthy controls, there was a significant decrease in absolute FA of WM around the bilateral anterior cingulate gyrus and the right anterior corona radiata of the frontal lobe in first-episode drug-naive patients with schizophrenia following 6 weeks of treatment. Clinical symptoms improved during this period but the change in FA did not correlate with the changes in clinical symptoms or the dose of antipsychotic medication.ConclusionsDuring the early phase of treatment, there is an acute reduction in WM FA that may be due to the effects of antipsychotic medications. However, it is not possible to entirely exclude the effects of underlying progression of illness.

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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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Tract-Based Spatial Statistics: Application to Mild Cognitive Impairment

BioMed Research International ◽

10.1155/2014/713079 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Yau-Yau Wai ◽

Wen-Chuin Hsu ◽

Hon-Chung Fung ◽

Jiann-Der Lee ◽

Hsiao-Lung Chan ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

White Matter ◽

Apolipoprotein E ◽

Spatial Statistics ◽

Diffusion Tensor ◽

Cerebral White Matter ◽

Brain White Matter ◽

Amnestic Mci ◽

Tract Based Spatial Statistics

Rationale and Objectives. The primary objective of the current investigation was to characterize white matter integrity in different subtypes of mild cognitive impairment (MCI) using tract-based spatial statistics of diffusion tensor imaging.Materials and Methods. The study participants were divided into 4 groups of 30 subjects each as follows: cognitively healthy controls, amnestic MCI, dysexecutive MCI, and Alzheimer’s disease (AD). All subjects underwent a comprehensive neuropsychological assessment, apolipoprotein E genotyping, and 3-tesla MRI. The diffusion tensor was reconstructed and then analyzed using tract-based spatial statistics. The changes in brain white matter tracts were also examined according to the apolipoprotein Eε4 status.Results. Compared with controls, amnestic MCI patients showed significant differences in the cerebral white matter, where changes were consistently detectable in the frontal and parietal lobes. We found a moderate impact of the apolipoprotein Eε4 status on the extent of white matter disruption in the amnestic MCI group. Patients with AD exhibited similar but more extensive alterations, while no significant changes were observed in dysexecutive MCI patients.Conclusion. The results from this study indicate that amnestic MCI is the most likely precursor to AD as both conditions share significant white matter damage. By contrast, dysexecutive MCI seems to be characterized by a distinct pathogenesis.

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T48. DEVIATIONS IN MICRO AND MACRO WHITE MATTER STRUCTURES IN PSYCHOSIS PRONENESS

Schizophrenia Bulletin ◽

10.1093/schbul/sbaa029.608 ◽

2020 ◽

Vol 46 (Supplement_1) ◽

pp. S249-S250

Author(s):

Seda Arslan ◽

Tuba Şahin ◽

Didenur Şahin ◽

Timothea Toulopoulou

Keyword(s):

White Matter ◽

High Risk ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Structured Interview ◽

Anterior Cingulate ◽

White Matter Integrity ◽

Psychosis Proneness ◽

Brodmann Areas ◽

The Right

Abstract Background Psychotic disorders are characterized by neurobiological deviations, including in the macro and microstructure of white matter. White matter alterations are also seen in psychosis-proneness and in individuals who have a high risk of psychosis. For example, studies have indicated decreases in white matter integrity in the genu/forceps minor of corpus callosum (CC) in the latter populations. Anterior corona radiata (ACR) is one crucial white-matter tract connecting the anterior cingulate cortex to the striatum. Indeed, reductions in the white matter structure of anterior genu of CC significantly predict the transition from ultra-high risk to psychosis. However, there is a gap in the literature related to observing the psychosis-proneness by applying both micro and macrostructural brain analyses, and most of the microstructural white matter studies in psychosis focus on fractional anisotropy (FA) and not include mean diffusivity (MD). Thus, the current study aims to assess whether white matter deviations in CG, ACR, and CC, are associated with psychosis proneness by combining both tract-based spatial statistics (TBSS) and voxel-based morphometry (VBM) analyses in a sample of participants with psychosis proneness (PP) and without psychosis proneness (NPP). Methods The study included 53 participants (29 PP vs. 24 NPP) whose ages were between 17 and 24 years. Participants were split into two groups based on their scores on Structured Interview for Schizotypy assessment, a well-validated instrument of psychosis proneness. White matter integrity was analyzed via diffusion tensor imaging (DTI) and white matter volume (WMV) via VBM. Two sample t-test was used in GLM for both DTI and VBM analyses. FA, MD, and VMV were compared between two groups to observe micro and macro white matter structure alterations in the region of interest. Results DTI analysis revealed decreased FA values in the right ACR and right genu of the CC in the psychosis-proneness group (F(1,52)= 7.37, p= 0.009). Moreover, VBM showed a significant WMV decreases in the right CG, Brodmann areas 8, 9, and 32 in the PP group (F(1,52)= 50.85, uncorrected p<0.01). However, MD did not differ between the two groups (F(1,51)= 3.65, p=0.06) Discussion These findings suggest that PP associated with decreased white matter integrity in ACR, genu of CC, and also reduced white matter volumes in the right CG, Brodmann areas 8, 9, and 32. Significant FA decreases might result from alterations in radial or axial diffusivity since we did not observe significant MD differences between two groups. The current findings suggested that participants with PP had both macro and micro white matter structure disruptions, mostly in frontal parts of the right cerebrum, compared to no PP group.

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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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Hockey Concussion Education Project, Part 3. White matter microstructure in ice hockey players with a history of concussion: a diffusion tensor imaging study

Journal of Neurosurgery ◽

10.3171/2013.12.jns132092 ◽

2014 ◽

Vol 120 (4) ◽

pp. 882-890 ◽

Cited By ~ 53

Author(s):

Takeshi Sasaki ◽

Ofer Pasternak ◽

Michael Mayinger ◽

Marc Muehlmann ◽

Peter Savadjiev ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Diffusion Tensor ◽

Ice Hockey ◽

Cognitive Test ◽

Corona Radiata ◽

White Matter Microstructure ◽

Hockey Players ◽

History Of ◽

The Right

Object The aim of this study was to examine the brain's white matter microstructure by using MR diffusion tensor imaging (DTI) in ice hockey players with a history of clinically symptomatic concussion compared with players without a history of concussion. Methods Sixteen players with a history of concussion (concussed group; mean age 21.7 ± 1.5 years; 6 female) and 18 players without a history of concussion (nonconcussed group; mean age 21.3 ± 1.8 years, 10 female) underwent 3-T DTI at the end of the 2011–2012 Canadian Interuniversity Sports ice hockey season. Tract-based spatial statistics (TBSS) was used to test for group differences in fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and the measure “trace,” or mean diffusivity. Cognitive evaluation was performed using the Immediate Postconcussion Assessment and Cognitive Test (ImPACT) and the Sport Concussion Assessment Tool–2 (SCAT2). Results TBSS revealed a significant increase in FA and AD, and a significant decrease in RD and trace in several brain regions in the concussed group, compared with the nonconcussed group (p < 0.05). The regions with increased FA and decreased RD and trace included the right posterior limb of the internal capsule, the right corona radiata, and the right temporal lobe. Increased AD was observed in a small area in the left corona radiata. The DTI measures correlated with neither the ImPACT nor the SCAT2 scores. Conclusions The results of the current study indicate that a history of concussion may result in alterations of the brain's white matter microstructure in ice hockey players. Increased FA based on decreased RD may reflect neuroinflammatory or neuroplastic processes of the brain responding to brain trauma. Future studies are needed that include a longitudinal analysis of the brain's structure and function following a concussion to elucidate further the complex time course of DTI changes and their clinical meaning.

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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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