scholarly journals Combining Electrostimulation With Fiber Tracking to Stratify the Inferior Fronto-Occipital Fasciculus

2021 ◽  
Vol 15 ◽  
Author(s):  
Alexandre Roux ◽  
Anne-Laure Lemaitre ◽  
Jeremy Deverdun ◽  
Sam Ng ◽  
Hugues Duffau ◽  
...  
Keyword(s):  
Awake Surgery ◽  
Low Grade ◽  
Network Organization ◽  
Hemispheric Differences ◽  
Interindividual Variations ◽  
Fiber Tracts ◽  
The Right ◽  
Subcortical Mapping ◽  
High Degree

The inferior fronto-occipital fasciculus (IFOF) is one of the longest association fiber tracts of the brain. According to the most recent anatomical studies, it may be formed by several layers, suggesting a role in multiple cognitive functions. However, to date, no attempt has been made to dissociate the functional contribution of the IFOF subpathways. In this study, real-time, cortico-subcortical mapping with direct electrostimulation was performed in 111 patients operated on in wide-awake surgery for a right low-grade glioma. Patients performed two behavioral tasks during stimulation, tapping, respectively, mentalizing and visual semantic cognition—two functions supposed to be partly mediated by the IFOF. Responsive white matter sites were first subjected to a clustering analysis to assess potential topological differences in network organization. Then they were used as seeds to generate streamline tractograms based on the HC1021 diffusion dataset (template-based approach). The tractograms obtained for each function were overlapped and contrasted to determine whether some fiber pathways were more frequently involved in one or the other function. The obtained results not only provided strong evidence for a role of the right IFOF in both functions, but also revealed that the tract is dissociable into two functional strata according to a ventral (semantic) and dorsal (mentalizing) compartmentalization. Besides, they showed a high degree of anatomo-functionnal variability across patients in the functional implication of the IFOF, possibly related to symmetrical/hemispheric differences in network organization. Collectively, these findings support the view that the right IFOF is a functionally multi-layered structure, with nevertheless interindividual variations.

Disrupting the right pars opercularis with electrical stimulation frees the song: case report

2015 ◽  
Vol 123 (6) ◽  
pp. 1401-1404 ◽  
Author(s):  
Guillaume Herbet ◽  
Gilles Lafargue ◽  
Fabien Almairac ◽  
Sylvie Moritz-Gasser ◽  
François Bonnetblanc ◽  
...  
Keyword(s):  
Language Production ◽  
Inferior Frontal Gyrus ◽  
Awake Surgery ◽  
Low Grade ◽  
Speech Impairment ◽  
First Case ◽  
Pars Opercularis ◽  
The Right

The authors report the first case of a strikingly unusual speech impairment evoked by intraoperative electrostimulation in a 36-year-old right-handed patient, a well-trained singer, who underwent awake surgery for a right fronto-temporo-insular low-grade glioma. Functionally disrupting the pars opercularis of the right inferior frontal gyrus led the patient to automatically switch from a speaking to a singing mode of language production. Given the central role of the right pars opercularis in the inhibitory control network, the authors propose that this finding may be interpreted as possible evidence for a competitive and independent neurocognitive subnetwork devoted to the melodically intoned articulation of words (normal language-based vs singing-based) in subjects with high expertise. From a more clinical perspective, such data may have implications for awake neurosurgery, especially to preserve the quality of life for singers.

Involvement of the right inferior longitudinal fascicle in visual hemiagnosia: a brain stimulation mapping study

2013 ◽  
Vol 118 (1) ◽  
pp. 202-205 ◽  
Author(s):  
Alejandro Fernández Coello ◽  
Sophie Duvaux ◽  
Alessandro De Benedictis ◽  
Ryosuke Matsuda ◽  
Hugues Duffau
Keyword(s):  
Brain Stimulation ◽  
Brain Mapping ◽  
Visual Recognition ◽  
Awake Surgery ◽  
Low Grade ◽  
Mapping Study ◽  
Visual Agnosia ◽  
The Right ◽  
Tractography Data

Neural foundations underlying visual agnosia are poorly understood. The authors present the case of a patient who underwent awake surgery for a right basal temporooccipital low-grade glioma in which direct electrostimulation was used both at the cortical and subcortical level. Brain mapping over the inferior longitudinal fascicle generated contralateral visual hemiagnosia. These original findings are in agreement with recent tractography data that have confirmed the existence of an occipitotemporal pathway connecting occipital visual input to higher-level processing in temporal lobe structures. This is the first report of a true transient visual hemiagnosia elicited through electrostimulation, supporting the crucial role of inferior longitudinal fascicle in visual recognition.

scholarly journals THERMOREGULATION IN THE HEART AND THE BIOPHYSICS OF CORONARY ARTERIAL FLOW

2013 ◽  
Vol 03 (02) ◽  
pp. 058-062
Author(s):  
Arunachalam Kumar
Keyword(s):  
Systolic Pressure ◽  
Physical Force ◽  
Rapid Action ◽  
Number Of Factors ◽  
Flow Through ◽  
The Right ◽  
Muscular Pump ◽  
Physical Laws ◽  
High Degree

AbstractThe right and left coronary arteries are the principal sources of supply of oxygenated blood to the heart. Arising from the proximal rim of the ascending aorta, these arteries course along and over the surface of the organ, sending out branches that penetrate axial blood flow through arteries is governed or maintained by multifarious physical laws.The heart, an electrically stimulated muscular pump, squirts and receives circulating blood through its systolic and diastolic exertions. The non-stop life-long rapid action of the organ not just expends enormous energy but also generates considerable heat. While there are a number of factors that help the heart dissipate and reduce heat, a few other biophysical factors contribute hugely to maintain a thermostatic milieu.Circulation through vessels is maintained with a high degree of efficiency through combined actions of ejection systolic pressure, elasticity of the conducting arterial channels, and the proximo-distal decrease in diameters of arteries.This brief write-up discusses some of physics regulatng fluid flow dynamics and attempts to exemplify the significant role of 'centrifugal force' as a hitherto overlooked physical force in coronary haemodynamics. The application of biophysical postulates to cardiac cycle may help in furthering our understanding of coronary blood circulation and the multi-factorial influences on its functional integrity. It is inferenced that, the finding may have a number of applications and result in a better understanding of cardiac circulatory dynamics.

scholarly journals Relation Between Reading Performance and White-Matter Alteration and Reorganization in Neurosurgical Patients

2020 ◽  
Vol 11 ◽  
Author(s):  
Elisa Cargnelutti ◽  
Marta Maieron ◽  
Tamara Ius ◽  
Miran Skrap ◽  
Barbara Tomasino
Keyword(s):  
White Matter ◽  
Diffusion Tensor ◽  
Clinical Importance ◽  
Reading Performance ◽  
Low Grade ◽  
Reading Impairment ◽  
Reading Abilities ◽  
Neurosurgical Patients ◽  
The Right

Reading abilities and diffusion tensor imaging (DTI) parameters were retrospectively analyzed in a group of neurosurgical patients to investigate (Study 1) the role of white matter—in particular the arcuate fasciculus (AF)—in preserved vs. impaired reading; 4 months after surgery, we explored the plasticity processes (Study 2). Study 1 involved 40 patients with brain glioma (23 low-grade and 17 high-grade gliomas). We compared preoperative DTI parameters of language-related fascicles between patients who developed a reading impairment after surgery (n = 23) and patients with preserved reading (n = 17). Besides lower fractional anisotropy (FA), patients with impaired reading also displayed lower number and density of streamlines of a direct (i.e., directly connecting temporal and frontal lobes) AF segment. In Study 2, we longitudinally tested at follow-up-when reading performance had generally improved-13 patients diagnosed with low-grade glioma. The most relevant finding was a significant increase in length of streamlines of the direct AF segments in both hemispheres. From a neurosurgical perspective, our preliminary findings suggest the clinical importance of sparing direct AF segments for the involvement they showed in reading; however, the results also suggest the reorganization potential of these segments, possibly compensating of the right homologs as well.

HOW OPEN LIST PROPORTIONAL REPRESENTATION WORKS IN THE 2020 LOCAL ELECTIONS AT KHARKIV REGION?

2020 ◽  
Keyword(s):  
Electoral System ◽  
Proportional Representation ◽  
Local Elections ◽  
Party Leadership ◽  
Regional Council ◽  
City Councils ◽  
Election Results ◽  
The Right ◽  
High Degree

The article examines the first approbation of the Electoral Code on the material of the 2020 local elections in the Kharkiv region. The authors pay special attention to the effects of open lists systems and the degree of influence of preferential votes on the personal distribution of seats in local councils. The article calculates the percentage of voters who used the right of preferential votes in all 14 constituencies and main party lists. We argue that according to the indicators of the use of the preferential vote right and the percentage of invalid ballots, the voters of the Kharkiv region demonstrated a high degree of adaptive readiness for the new electoral system. The article analyzes the effects of blocking mechanisms incorporated in the electoral system, which reduced the influence of preferential votes of voters and retained the control of the party leadership over the personal distribution of mandates in the councils. The ratio between the seats from the district lists and the unified closed party lists was quantified (based on election results for the regional council and 17 city councils of the region). The article analyzes the intensity of changes in the ballot position of candidates in the district lists on regional council elections. We demonstrate that only 20% of seats were received by candidates placed by the party leadership in a “no-pass” ballot position. The article argues that the electoral formula introduced in the 2020 local elections did not work as a system with open lists proportional representation. According to the statistics of the personal allocation of seats in the newly elected councils, this model seems to be something in between the systems of flexible and closed lists. In this regard, the article develops new arguments in the debate on how the norms of electoral legislation reduce the role of preferential votes of voters and proposes recommendations for amending the Electoral Code.

scholarly journals Neuropsychological Outcomes After Awake Resections of Right Frontal IDH-Mutated Glioma: Insights From a Consecutive Series of 20 Cases.

2021 ◽  
Author(s):  
Marion Barberis ◽  
Isabelle Poisson ◽  
Valentine Facque ◽  
Sophie Letrange ◽  
Cécile Prévost-Tarabon ◽  
...  
Keyword(s):  
Frontal Lobe ◽  
Cognitive Deficits ◽  
Spatial Neglect ◽  
Awake Surgery ◽  
Consecutive Series ◽  
Low Grade ◽  
Worth Living ◽  
Behavioral Impairment ◽  
Dysexecutive Syndrome ◽  
The Right

Abstract Background Awake surgery for low-grade gliomas is currently considered the best procedure to improve the extent of resection and guarantee a "worth living life" for patients, meaning avoiding not only motor but also cognitive deficits. However, tumors located in the right hemisphere, especially in the right frontal lobe, are still rarely operated on in awake condition; one of the reasons possibly being that there is little information in the literature describing the rates and nature of long-lasting neuropsychological deficits following resection of right frontal glioma. Objective To investigate long-term cognitive deficits after awake surgery in right frontal IDH-mutated glioma. Methods We retrospectively analyzed a consecutive series of awake surgical resections between 2012 and 2020 for right frontal IDH-mutated glioma. We studied the patients' subjective complaints and objective neuropsychological evaluations, both before and after surgery. Our results were then put in perspective with the literature. Results Twenty surgical cases (including 5 cases of redo surgery) in eighteen patients (medium age: 42.5 [range 26–58]) were included in the study. The median preoperative volume was 37 cc; WHO grading was II, III and IV in 70%, 20%, and 10% of cases, respectively. Preoperatively, few patients had related subjective cognitive or behavioral impairment, while evaluations revealed mild deficits in 45% of cases, most often concerning executive functions, attention, working memory and speed processing. Immediate postoperative evaluations showed severe dysexecutive syndrome in 75% of cases but also attentional deficits (65%), spatial neglect (60%) and behavioral disturbances (apathy, aprosodia/amimia, emotional sensitivity, anosognosia). Four months after surgery, although psychometric z-scores were unchanged at the group level, individual evaluations showed a slight decrease in performance in 9/20 cases (dysexecutive syndrome, speed processing, attention, semantic cognition, social cognition). Conclusion Our results are generally consistent with those of the literature, confirming that the right frontal lobe is a highly eloquent area and highlighting the importance of operating these patients in awake conditions.

scholarly journals A Proposed Educational Vision For Activating The Role of The Jordanian Universities Students Families In Enhancing Students Intellectual Security From The Students Perspectives

2016 ◽  
Vol 12 (16) ◽  
pp. 105
Author(s):  
Khloud Falah Ahmad Rahamneh ◽  
Mohammed Amin Hamed Al- Qudah
Keyword(s):  
Analytical Approach ◽  
Basic Function ◽  
Early Age ◽  
Educational Vision ◽  
The Social ◽  
Cultural Domain ◽  
The Right ◽  
The University ◽  
High Degree

This study aimed to find out the role of the Jordanian families in establishing intellectual security in their children from the perspective of the Jordanian students enrolled in Jordanian universities. For this purpose, a questionnaire of 36 paragraphs was created. The questionnaire was divided into three domains: the social, the cultural and the religious domains. The study was conducted on a random sample of (2700) students from three public universities (the University of Jordan, Yarmouk University, Moa'ta University and Al-Balqa' Applied University) and three private universities (Amman Al-Ahliah, Azzaytouna al-Ordiniah and Jerash). The study was conducted during the second university term of 2015/2016 CE. The descriptive analytical approach was used. The study showed that the three domains (social, cultural and religious) were of high degree. The highest of them was the cultural domain. The two paragraphs which state (the family's quest to build a cultural system emerging from our religion, values, traditions and customs, consolidating the values of the theoretical and practical dimensions of moderation among children) occupied the first rank, followed by the social domain. The paragraph which states that (The family's doing its basic function of education and socialization) occupied the first rank, whereas the religious domain occupied the last one. The paragraph which states (The family's seeking to form the right belief at an early age) occupied the first rank.

scholarly journals Possible Role of Leptin in Atopic Dermatitis: A Literature Review

Biomolecules ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1642
Author(s):  
Carlos Jiménez-Cortegana ◽  
Germán Ortiz-García ◽  
Amalia Serrano ◽  
David Moreno-Ramírez ◽  
Víctor Sánchez-Margalet
Keyword(s):  
Atopic Dermatitis ◽  
Skin Disease ◽  
Skin Diseases ◽  
Allergic Diseases ◽  
Developed Countries ◽  
Low Grade ◽  
New Biomarkers ◽  
Age Range ◽  
High Degree

Atopic dermatitis (AD) is the most frequent chronic inflammatory skin disease, and its incidence has been rapidly increasing in developed countries in the last years. AD presents a high degree of heterogeneity due to biases and confounding factors such as age range, sex, or ethnicity. For those reasons, the search for new biomarkers is crucial. At the same time, obesity, which is a global health problem, has also increased over the years. It has been associated with many pathophysiological states, including skin diseases such as AD, mostly in childhood. Obesity promotes a low grade inflammation driven by many different cytokines and adipokines, including leptin, which has a key role in many other diseases due to its pleiotropic effects. Leptin also has a role in both skin and allergic diseases very related to AD. Thus, this adipokine could have an important role in the pathogenesis of AD, especially in its chronicity. Despite the limited literature available, there is some evidence that leads us to consider leptin as an important adipokine in this skin disease. For this reason, here we have reviewed the role of leptin in the pathophysiology of AD.

scholarly journals Impaired Set-Shifting from Dorsal Stream Disconnection: Insights from a European Series of Right Parietal Lower-Grade Glioma Resection

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3337
Author(s):  
Suzanne L. Hartung ◽  
Emmanuel Mandonnet ◽  
Philip de Witt Hamer ◽  
Martin Klein ◽  
Michel Wager ◽  
...  
Keyword(s):  
Stroop Task ◽  
Right Hemisphere ◽  
Parietal Lobe ◽  
Dorsal Stream ◽  
Awake Surgery ◽  
Lateral Part ◽  
Low Grade ◽  
Lower Grade ◽  
Set Shifting ◽  
The Right

Awake surgery with cognitive monitoring has increasingly been implemented to preserve brain networks and functionality. More recently, not only surgery in the left but also in the right hemisphere, i.c., the parietal lobe, was associated with potential risk for deficits in cognitive functions, such as cognitive flexibility. In this explorative pilot study, we compare cognitive performance more than three months after surgery with baseline measurements and explore the association between cognitive decline and subcortical tracts that may have been severed during surgery in the right hemisphere. Twenty-two patients who underwent surgery for a right parietal low-grade glioma were assessed pre- and postoperatively using the Trail Making Test and the Stroop task to administer set-shifting abilities and inhibition. Volume measurements and lesion–symptom mapping analyses were performed on postoperative MRI scans. Careful interpretation of the results shows a change in TMT performance and not on the Stroop Task when the lateral part of the arcuate fasciculus is damaged, indicating that disconnection of the lateral part of the dorsal stream might be correlated specifically with impaired set-shifting and not with inhibition. More importantly, this study underlines the need for international concertation to allow larger studies to increase power and perform more detailed analyses.

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