scholarly journals Altered integrity of corpus callosum in generalized epilepsy in relation to seizure lateralization after corpus callosotomy

2020 ◽  
Vol 48 (4) ◽  
pp. E15 ◽  
Author(s):  
Po Ching Chen ◽  
Steven A. Messina ◽  
Eduardo Castillo ◽  
James Baumgartner ◽  
Joo Hee Seo ◽  
...  
Keyword(s):  
Corpus Callosum ◽  
Structural Damage ◽  
Structural Integrity ◽  
Diffusion Tensor ◽  
Case Series ◽  
Structural Difference ◽  
The Body ◽  
Corpus Callosotomy ◽  
Major Pathway ◽  
Generalized Epilepsy

OBJECTIVEGeneralized-onset seizures are usually conceptualized as engaging bilaterally distributed networks with no clear focus. However, the authors previously reported a case series demonstrating that in some patients with generalized-onset seizures, focal seizure onset could be discovered after corpus callosotomy. The corpus callosum is considered to be a major pathway for seizure generalization in this group of patients. The authors hypothesized that, in patients with generalized-onset seizures, the structure of the corpus callosum could be different between patients who have lateralized seizures and those who have nonlateralized seizures after corpus callosotomy. The authors aimed to evaluate the structural difference through statistical analysis of diffusion tensor imaging (DTI) scalars between these two groups of patients.METHODSThirty-two patients diagnosed with generalized-onset motor seizures and without an MRI lesion were included in this study. Among them, 16 patients developed lateralized epileptic activities after corpus callosotomy, and the remaining 16 patients continued to have nonlateralized seizures after corpus callosotomy. Presurgical DTI studies were acquired to quantify the structural integrity of the corpus callosum.RESULTSThe DTI analysis showed significant reduction of fractional anisotropy (FA) and increase in radial diffusivity (RD) in the body of the corpus callosum in the lateralized group compared with the nonlateralized group.CONCLUSIONSThe authors’ findings indicate the existence of different configurations of bilateral epileptic networks in generalized epilepsy. Generalized seizures with focal onset relying on rapid spread through the corpus callosum might cause more structural damage related to demyelination in the corpus callosum, showing reduced FA and increased RD. This study suggests that presurgical DTI analysis of the corpus callosum might predict the seizure lateralization after corpus callosotomy.

scholarly journals Structural brain signature of cognitive decline in Parkinson’s disease: DTI-based evidence from the LANDSCAPE study

2019 ◽  
Vol 12 ◽  
pp. 175628641984344 ◽  
Author(s):  
Martin Gorges ◽  
Hans-Peter Müller ◽  
Inga Liepelt-Scarfone ◽  
Alexander Storch ◽  
Richard Dodel ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
White Matter ◽  
Corpus Callosum ◽  
Cognitive Decline ◽  
Diffusion Tensor ◽  
Structural Connectivity ◽  
Structural Data ◽  
The Body ◽  
Normal Cognitive Function

Background: The nonmotor symptom spectrum of Parkinson’s disease (PD) includes progressive cognitive decline mainly in late stages of the disease. The aim of this study was to map the patterns of altered structural connectivity of patients with PD with different cognitive profiles ranging from cognitively unimpaired to PD-associated dementia. Methods: Diffusion tensor imaging and neuropsychological data from the observational multicentre LANDSCAPE study were analyzed. A total of 134 patients with PD with normal cognitive function (56 PD-N), mild cognitive impairment (67 PD-MCI), and dementia (11 PD-D) as well as 72 healthy controls were subjected to whole-brain-based fractional anisotropy mapping and covariance analysis with cognitive performance measures. Results: Structural data indicated subtle changes in the corpus callosum and thalamic radiation in PD-N, whereas severe white matter impairment was observed in both PD-MCI and PD-D patients including anterior and inferior fronto-occipital, uncinate, insular cortices, superior longitudinal fasciculi, corona radiata, and the body of the corpus callosum. These regional alterations were demonstrated for PD-MCI and were more pronounced in PD-D. The pattern of involved regions was significantly correlated with the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) total score. Conclusions: The findings in PD-N suggest impaired cross-hemispherical white matter connectivity that can apparently be compensated for. More pronounced involvement of the corpus callosum as demonstrated for PD-MCI together with affection of fronto-parieto-temporal structural connectivity seems to lead to gradual disruption of cognition-related cortico-cortical networks and to be associated with the onset of overt cognitive deficits. The increase of regional white matter damage appears to be associated with the development of PD-associated dementia.

scholarly journals White matter abnormalities of corpus callosum in patients with bipolar disorder and suicidal ideation

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Ran Zhang ◽  
Xiaowei Jiang ◽  
Miao Chang ◽  
Shengnan Wei ◽  
Yanqing Tang ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
White Matter ◽  
Suicidal Ideation ◽  
Corpus Callosum ◽  
Diffusion Tensor ◽  
The Body ◽  
Pathophysiological Mechanism ◽  
The Relationship ◽  
Diffusion Tensor Imaging Dti

Abstract Objective Although many studies have shown that the corpus callosum (CC) may play an important role in bipolar disorder (BD) and suicide, the pathophysiological mechanism of BD underlying suicidal behavior is still unclear. This study aimed to explore the relationship between the CC, and BD and suicidal ideation using diffusion tensor imaging (DTI). Method A total of 203 participants (47 BD patients with suicidal ideation, 59 with BD without suicidal ideation, and 97 healthy controls [HC]) underwent DTI scanning at a single site. We examined the white matter integrity of the CC in the three groups. Results A comparison among groups showed that BD patients with suicidal ideation had significant lower fractional anisotropy (FA) values than those of BD without suicidal ideation and HCs in the body and genu of the CC, and FA values of BD without suicidal ideation were significantly lower than those of HCs. However, in the splenium of corpus callosum, no difference was found between BD without suicidal ideation and HCs. Conclusions Our findings add to the evidence suggesting that the CC plays a key role in BD with suicidal ideation, especially with respect to the role of the genu and body of the CC subserving emotion regulation.

scholarly journals Preservation of electrophysiological functional connectivity after partial corpus callosotomy: case report

2018 ◽  
Vol 22 (2) ◽  
pp. 214-219 ◽  
Author(s):  
Kaitlyn Casimo ◽  
Fabio Grassia ◽  
Sandra L. Poliachik ◽  
Edward Novotny ◽  
Andrew Poliakov ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Corpus Callosum ◽  
Seizure Activity ◽  
Diffusion Tensor ◽  
Phase Locking ◽  
Corpus Callosotomy ◽  
Left And Right ◽  
Phase Locking Value ◽  
Anatomical Mri ◽  
Electrophysiological Methods

Prior studies of functional connectivity following callosotomy have disagreed in the observed effects on interhemispheric functional connectivity. These connectivity studies, in multiple electrophysiological methods and functional MRI, have found conflicting reductions in connectivity or patterns resembling typical individuals. The authors examined a case of partial anterior corpus callosum connection, where pairs of bilateral electrocorticographic electrodes had been placed over homologous regions in the left and right hemispheres. They sorted electrode pairs by whether their direct corpus callosum connection had been disconnected or preserved using diffusion tensor imaging and native anatomical MRI, and they estimated functional connectivity between pairs of electrodes over homologous regions using phase-locking value. They found no significant differences in any frequency band between pairs of electrodes that had their corpus callosum connection disconnected and those that had an intact connection. The authors’ results may imply that the corpus callosum is not an obligatory mediator of connectivity between homologous sites in opposite hemispheres. This interhemispheric synchronization may also be linked to disruption of seizure activity.

Functional Connectivity: Integrating Behavioral, Diffusion Tensor Imaging, and Functional Magnetic Resonance Imaging Data Sets

2005 ◽  
Vol 17 (4) ◽  
pp. 687-693 ◽  
Author(s):  
Abigail A. Baird ◽  
Mary K. Colvin ◽  
John D. VanHorn ◽  
Souheil Inati ◽  
Michael S. Gazzaniga
Keyword(s):  
Diffusion Tensor Imaging ◽  
Individual Differences ◽  
Magnetic Resonance ◽  
Corpus Callosum ◽  
Information Transfer ◽  
Structural Integrity ◽  
Diffusion Tensor ◽  
Bold Response ◽  
Imaging Data ◽  
Imaging Results

In the present study, we combined 2 types of magnetic resonance technology to explore individual differences on a task that required the recognition of objects presented from unusual viewpoints. This task was chosen based on previous work that has established the necessity of information transfer from the right parietal cortex to the left inferior cortex for its successful completion. We used reaction times (RTs) to localize regions of cortical activity in the superior parietal and inferior frontal regions (blood oxygen level-dependent [BOLD] response) that were more active with longer response times. These regions were then sampled, and their signal change used to predict individual differences in structural integrity of white matter in the corpus callosum (using diffusion tensor imaging). Results show that shorter RTs (and associated increases in BOLD response) are associated with increased organization in the splenium of the corpus callosum, whereas longer RTs are associated with increased organization in the genu.

scholarly journals The ipsilateral silent period: an early diagnostic marker of callosal disconnection in ALS

2021 ◽  
Vol 12 ◽  
pp. 204062232110440
Author(s):  
Annemarie Hübers ◽  
Jan Kassubek ◽  
Hans-Peter Müller ◽  
Nicolas Broc ◽  
Jens Dreyhaupt ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Diagnostic Marker ◽  
Diffusion Tensor ◽  
Diagnostic Delay ◽  
Silent Period ◽  
The Body ◽  
Diagnostic Tools ◽  
Microstructural Alterations ◽  
Early Stages ◽  
Early Diagnostic

Introduction: Imaging studies showed affection of the corpus callosum (CC) in amyotrophic lateral sclerosis (ALS). Here, we sought to determine whether these structural alterations reflect on the functional level, using transcranial magnetic stimulation (TMS). Methods: In 31 ALS patients and 12 controls, we studied mirror movements (MM) and transcallosal inhibition (TI) using TMS. Structural integrity of transcallosal fibres was assessed using diffusion tensor imaging. Results: TI was pathologic in 25 patients (81%), 22 (71%) showed MM. Loss of TI was observed in very early stages (disease duration <4 months). No correlation was found between TI/MM and fractional anisotropy of transcallosal fibres. Discussion: These results substantiate the body of evidence towards a functional involvement of the CC in early ALS beyond microstructural alterations. Significance: TI may become a useful early diagnostic marker in ALS, even before descending tracts are affected. Diagnostic delay in ALS is high, often preventing patients from gaining access to therapeutic trials, and sensitive diagnostic tools are urgently needed. Our findings also provide insights into the pathophysiology of ALS, potentially supporting the so-called ‘top-down’ hypothesis, that is, corticoefferent (intracortical/corticospinal) propagation. Callosal affection in early stages might represent the ‘missing link’ to explain corticocortical disease-spreading.

scholarly journals Effects of BDNF Val66Met Polymorphism on White Matter Microalterations of the Corpus Callosum in Patients with Panic Disorder in Korean Populations

2020 ◽  
Vol 17 (10) ◽  
pp. 967-975
Author(s):  
Hyun-Ju Kim ◽  
Minji Bang ◽  
Kang Soo Lee ◽  
Tai Kiu Choi ◽  
Chun Il Park ◽  
...  
Keyword(s):  
White Matter ◽  
Panic Disorder ◽  
Corpus Callosum ◽  
Diffusion Tensor ◽  
The Body ◽  
Imaging Data ◽  
Symptom Scale ◽  
Val66met Polymorphism ◽  
Scale Scores ◽  
Bdnf Val66met Polymorphism

Objective The brain-derived neurotrophic factor (<i>BDNF</i>) Val66Met (rs6265) polymorphism is suggested to be associated with the pathophysiology of anxiety disorders, including panic disorder (PD). Although the fronto-limbic white matter (WM) microstructures have been investigated, the corpus callosum (CC) has not yet been studied regarding its relationship with <i>BDNF</i> Val66Met polymorphism in PD.Methods Ninety-five PD patients were enrolled. The Neuroticism, the Anxiety Sensitivity Inventory-Revised, Panic Disorder Severity Scale, and Beck Depression Inventory-II (BDI-II) were administered. Voxel-wise statistical analysis of diffusion tensor imaging data was performed within the CC regions using Tract-Based Spatial Statistics.Results The GG genotype in <i>BDNF</i> Val66Met polymorphism has significantly higher fractional anisotropy (FA) values of the body and splenium of the CC, neuroticism and depressive symptom scale scores than the non-GG genotype in PD. The FA values of the body of the CC in the two groups were significantly different independent of age, sex, neuroticism, and BDI-II.Conclusion Our findings demonstrate that the <i>BDNF</i> Val66Met polymorphism is associated with WM connectivity of the body and splenium of the CC, and may be related to neuroticism and depressive symptoms in PD. Additionally, the CC connectivity according to BDNF polymorphism may play a role in the pathophysiology of PD.

scholarly journals Diffusion tensor MR imaging evaluation of the corpus callosum of patients with multiple sclerosis

2008 ◽  
Vol 66 (3a) ◽  
pp. 449-453 ◽  
Author(s):  
Fernanda Rueda ◽  
Luiz Celso Hygino Jr ◽  
Romeu Cortês Domingues ◽  
Cláudia C. Vasconcelos ◽  
Regina M. Papais-Alvarenga ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Corpus Callosum ◽  
Mr Imaging ◽  
Diffusion Tensor ◽  
The Body ◽  
Imaging Evaluation ◽  
Imaging Protocol ◽  
Posterior Portion ◽  
Normal Appearing White Matter ◽  
Relapsing Remitting

OBJECTIVE: To evaluate the fractional anisotropy (FA) values of the normal-appearing white matter of the corpus callosum (CC) in patients with relapsing-remitting multiple sclerosis (MS). METHOD: Fifty-seven patients with diagnosis of relapsing-remitting MS and 47 age- and gender-matched controls were studied. A conventional MR imaging protocol and a DTI sequence were performed. One neuroradiologist placed the regions of interest (ROIs) in the FA maps in five different portions of the normal-apearing CC (rostrum, genu, anterior and posterior portion of the body and splenium) in all cases. The statistical analysis was performed with the Mann-Whitney U test and p<0.05 was considered statistically significant. RESULTS: The FA values were lower in the MS patients compared with the controls (p<0.05) in the following CC regions: rostrum (0.720 vs 0.819), anterior body (0.698 vs 0.752), posterior body (0.711 vs 0.759) and splenium (0.720 vs 0.880). CONCLUSION: In this series, there was a robust decrease in the FA in all regions of the normal-appearing CC, being significant in the rostrum, body and splenium. This finding suggests that there is a subtle and diffuse abnormality in the CC, which could be probably related to myelin content loss, axonal damage and gliosis.

Postshunting corpus callosum swelling with depiction on tractography

2013 ◽  
Vol 11 (2) ◽  
pp. 178-180 ◽  
Author(s):  
Daniel T. Ginat ◽  
Sanjay P. Prabhu ◽  
Joseph R. Madsen
Keyword(s):  
Diffusion Tensor Imaging ◽  
White Matter ◽  
Corpus Callosum ◽  
Posterior Margin ◽  
Diffusion Tensor ◽  
The Body ◽  
Transverse Orientation ◽  
Chronic Hydrocephalus ◽  
Fiber Tracts ◽  
White Matter Fiber Tracts

Alterations in the appearance of the corpus callosum occasionally occur following successful ventricular decompression in patients with chronic hydrocephalus. There are certain features on imaging that suggest the diagnosis of what the authors propose be termed “postshunting corpus callosum swelling,” including diffuse high T2 signal predominantly affecting the body of the corpus callosum, with transverse orientation along the crossing white matter tracts and scalloping along the posterior margin of the structure. In this report, the authors demonstrate preservation of the corpus callosum white matter fiber tracts by using diffusion tensor imaging with tractography.

scholarly journals Structural network topology and microstructural alterations of the anterior insula associate with cognitive and affective impairment in Parkinson’s disease

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
L. E. Jonkman ◽  
Y. Y. Fathy ◽  
H. W. Berendse ◽  
M. M. Schoonheim ◽  
W. D. J. van de Berg
Keyword(s):  
Structural Damage ◽  
Structural Integrity ◽  
Diffusion Tensor ◽  
Mean Diffusivity ◽  
Insular Cortex ◽  
Anterior Cingulate ◽  
Salience Network ◽  
Semantic Fluency ◽  
Eigenvector Centrality ◽  
Microstructural Alterations

AbstractThe aim of the current study was to assess the structural centrality and microstructural integrity of the cortical hubs of the salience network, the anterior insular cortex (AIC) subregions and anterior cingulate cortex (ACC), and their relationship to cognitive and affective impairment in PD. MRI of 53 PD patients and 15 age-matched controls included 3D-T1 for anatomical registration, and diffusion tensor imaging for probabilistic tractography. Network topological measures of eigenvector and betweenness centrality were calculated for ventral (vAI) and dorsal (dAI) AIC. Microstructural tract integrity between vAI, dAI and the ACC was quantified with fractional anisotrophy (FA) and mean diffusivity (MD). Structural integrity and connectivity were related to cognitive and affective scores. The dAI had significantly higher eigenvector centrality in PD than controls (p < 0.01), associated with higher depression scores (left dAI only, rs = 0.28, p < 0.05). Tracts between dAI and ACC showed lower FA and higher MD in PD (p < 0.05), and associated with lower semantic fluency, working memory and executive functioning, and higher anxiety scores (range 0.002 < p < 0.05). This study provides evidence for clinically relevant structural damage to the cortical hubs of the salience network in PD, possibly due to extensive local neuropathology and loss of interconnecting AIC-ACC tracts.

Extraventricular corpus callosotomy

2011 ◽  
Vol 114 (6) ◽  
pp. 1698-1700 ◽  
Author(s):  
Jacob R. Joseph ◽  
Ashwin Viswanathan ◽  
Daniel Yoshor
Keyword(s):  
Corpus Callosum ◽  
Mr Imaging ◽  
Septum Pellucidum ◽  
The Body ◽  
Corpus Callosotomy ◽  
Cavum Septum Pellucidum ◽  
Drop Attacks ◽  
Lateral Ventricles ◽  
Intractable Seizures ◽  
Anatomical Basis

Corpus callosotomy offers useful palliation for selected patients with medically intractable seizures, particularly those with uncontrolled and disabling drop attacks. Here the authors present their technique for performing a corpus callosotomy that allows for complete sectioning of the callosum while avoiding entry into the lateral ventricles. The anatomical basis for the technique is the presence of a definable cleft just ventral to the corpus callosum in the midline, formed by the fusion of the two laminae of the septum pellucidum. This small cleft is typically present even in the absence of a cavum septum pellucidum on MR imaging. The authors have found that dividing the body of the corpus callosum by exploiting the cleft of the septum pellucidum in the absolute midline is a simple and expeditious way to perform a callosotomy without entering the lateral ventricles.

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