References of "Gosseries, Olivia"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSwallowing in individuals with disorders of consciousness: A cohort study
MELOTTE, Evelyne ULiege; MAUDOUX, Audrey ULiege; DELHALLE, Sabrina ULiege et al

in Annals of Physical and Rehabilitation Medicine (in press)

Background. After a period of coma, a proportion of individuals with severe brain injury remain in an altered state of consciousness before regaining partial or complete recovery. Individuals with ... [more ▼]

Background. After a period of coma, a proportion of individuals with severe brain injury remain in an altered state of consciousness before regaining partial or complete recovery. Individuals with disorders of consciousness (DOC) classically receive hydration and nutrition through an enteral feeding tube. However, the real impact of the level of consciousness on an individual’s swallowing ability remains poorly investigated. Objective. We aimed to document the incidence and characteristics of dysphagia in DOC individuals and to evaluate the link between different components of swallowing and the level of consciousness. Methods. We analyzed clinical data on the respiratory status, oral feeding and otolaryngologic examination of swallowing in DOC individuals. Univariate and multivariate logistic regression was used to analyse the association of components of swallowing and participant groups (i.e., unresponsive wakefulness syndrome [UWS] and minimally conscious state [MCS]). Results. We included 92 individuals with DOC (26 UWS and 66 MCS). Overall, 99% of the participants showed deficits in the oral and/or pharyngeal phase of swallowing. As compared with the MCS group, the UWS group more frequently had a tracheostomy (69% vs 24%), with diminished cough reflex (27% vs 54%) and no effective oral phase (0% vs 21%). Conclusion. Almost all DOC participants had severe dysphagia. Some components of swallowing (i.e., tracheostomy, cough reflex and efficacy of the oral phase of swallowing) were related to consciousness. In particular, no UWS participant had an efficient oral phase, which suggests that its presence may be a sign of consciousness. In addition, no UWS participant could be fed entirely orally, whereas no MCS participant orally received ordinary food. Our study also confirms that objective swallowing assessment can be successfully completed in DOC individuals and that specific care is needed to treat severe dysphagia in DOC. [less ▲]

Detailed reference viewed: 24 (4 ULiège)
Full Text
Peer Reviewed
See detailConsciousness and communication BCIs in severe brain-injured patients
Annen, Jitka ULiege; Laureys, Steven ULiege; Gosseries, Olivia ULiege

in Handbook Brain-Computer Interfacing: Neural Devices for paralysis in neurological practise and beyond (in press)

Detailed reference viewed: 210 (17 ULiège)
Full Text
Peer Reviewed
See detailDecreased evoked slow-activity after tDCS in disorders of consciousness
Mensen, Armand; BODART, Olivier ULiege; Thibaut, Aurore ULiege et al

in Frontiers in Systems Neuroscience (2020), 14(62),

Due to life-saving medical advances, the diagnosis and treatment of disorders of consciousness (DOC) has become a more commonly occurring clinical issue. One recently developed intervention option has ... [more ▼]

Due to life-saving medical advances, the diagnosis and treatment of disorders of consciousness (DOC) has become a more commonly occurring clinical issue. One recently developed intervention option has been non-invasive transcranial direct current stimulation. This dichotomy of patient responders may be better understood by investigating the mechanism behind the transcranial direct current stimulation (tDCS) intervention. The combination of transcranial magnetic stimulation and electroencephalography (TMS-EEG) has been an important diagnostic tool in DOC patients. We therefore examined the neural response using TMS-EEG both before and after tDCS in seven DOC patients (four diagnosed as in a minimally conscious state and three with unresponsive wakefulness syndrome). tDCS was applied over the dorsolateral prefrontal cortex, while TMS pulses were applied to the premotor cortex. None of the seven patients showed relevant behavioral change after tDCS. We did, however, find that the overall evoked slow activity was reduced following tDCS intervention. We also found a positive correlation between the strength of the slow activity and the amount of high-frequency suppression. However, there was no significant pre-post tDCS difference in high frequencies. In the resting-state EEG, we observed that both the incidence of slow waves and the positive slope of the wave were affected by tDCS. Taken together, these results suggest that the tDCS intervention can reduce the slow-wave activity component of bistability, but this may not directly affect high-frequency activity. We hypothesize that while reduced slow activity may be necessary for the recovery of neural function, especially consciousness, this alone is insufficient. [less ▲]

Detailed reference viewed: 38 (4 ULiège)
Full Text
Peer Reviewed
See detailNear-death experience as a probe to explore (disconnected) consciousness
Martial, Charlotte ULiege; Cassol, Helena ULiege; Laureys, Steven ULiege et al

in Trends in Cognitive Sciences (2020)

Forty-five years ago, the first evidence of near-death experience (NDE) during comatose state was provided, setting the stage for a new paradigm for studying the neural basis of consciousness in ... [more ▼]

Forty-five years ago, the first evidence of near-death experience (NDE) during comatose state was provided, setting the stage for a new paradigm for studying the neural basis of consciousness in unresponsive states. At present, the state of consciousness associated with NDEs remains an open question. In the common view, consciousness is said to disappear in a coma with the brain shutting down, but it is oversimplified. This article argues that the novel framework distinguishing awareness, wakefulness and connectedness is relevant to comprehend the phenomenon. Classical NDEs correspond to internal awareness experienced in unresponsive conditions, thereby corresponding to an episode of disconnected consciousness. Our proposal suggests new directions for NDE research, and more broadly, consciousness science. [less ▲]

Detailed reference viewed: 166 (15 ULiège)
Full Text
Peer Reviewed
See detailBrain metabolism but not grey matter volume underlies the presence of language function in the minimally conscious state
Aubinet, Charlène ULiege; Cassol, Helena ULiege; Gosseries, Olivia ULiege et al

in Neurorehabilitation and Neural Repair (2020), 34(2), 172-184

Background. The minimally conscious state (MCS) is subcategorized into MCS- and MCS+, depending on the absence or presence of high-level behavioral responses such as command following. Objective. We aim ... [more ▼]

Background. The minimally conscious state (MCS) is subcategorized into MCS- and MCS+, depending on the absence or presence of high-level behavioral responses such as command following. Objective. We aim to investigate the functional and structural neuroanatomy underlying the presence of these responses in MCS- and MCS+ patients. Methods. In this cross-sectional retrospective study, chronic MCS patients were diagnosed using repeated Coma Recovery Scale-Revised assessments. Fluorodeoxyglucose-positron emission tomography data were acquired on 57 patients (16 MCS-; 41 MCS+) and magnetic resonance imaging with voxel-based morphometry analysis was performed on 66 patients (17 MCS-; 49 MCS+). Brain glucose metabolism and grey matter integrity were compared between patient groups and control groups. A metabolic functional connectivity analysis testing the hypothesis of preserved language network in MCS+ compared to MCS- was also done. Results. Patients in MCS+ presented higher metabolism mainly in the left middle temporal cortex, known to be important for semantic processing, compared to the MCS- group. The left angular gyrus was also functionally disconnected from the left prefrontal cortex in MCS- compared to MCS+. No significant differences were found in grey matter volume between patient groups. Conclusions. The clinical sub-categorization of MCS is supported by differences in brain metabolism but not in grey matter structure, suggesting that brain function in the language network is the main support for recovery of command-following, intelligible verbalization and/or intentional communication in the MCS. Better characterizing the neural correlates of residual cognitive abilities of MCS patients contributes to reduce their misdiagnosis and to adapt therapeutic approaches. [less ▲]

Detailed reference viewed: 84 (29 ULiège)
Full Text
Peer Reviewed
See detailBrain Metabolism but Not Gray Matter Volume Underlies the Presence of Language Function in the Minimally Conscious State (MCS): MCS+ Versus MCS− Neuroimaging Differences
Aubinet, Charlène ULiege; Cassol, Helena ULiege; Gosseries, Olivia ULiege et al

in Neurorehabilitation and Neural Repair (2020), 34(2), 172-184

Background. The minimally conscious state (MCS) is subcategorized into MCS− and MCS+, depending on the absence or presence, respectively, of high-level behavioral responses such as command-following ... [more ▼]

Background. The minimally conscious state (MCS) is subcategorized into MCS− and MCS+, depending on the absence or presence, respectively, of high-level behavioral responses such as command-following. Objective. We aim to investigate the functional and structural neuroanatomy underlying the presence of these responses in MCS− and MCS+ patients. Methods. In this cross-sectional retrospective study, chronic MCS patients were diagnosed using repeated Coma Recovery Scale–Revised assessments. Fluorodeoxyglucose-positron emission tomography data were acquired on 57 patients (16 MCS−; 41 MCS+) and magnetic resonance imaging with voxel-based morphometry analysis was performed on 66 patients (17 MCS−; 49 MCS+). Brain glucose metabolism and gray matter integrity were compared between patient groups and control groups. A metabolic functional connectivity analysis testing the hypothesis of preserved language network in MCS+ compared with MCS− was also done. Results. Patients in MCS+ presented higher metabolism mainly in the left middle temporal cortex, known to be important for semantic processing, compared with the MCS− group. The left angular gyrus was also functionally disconnected from the left prefrontal cortex in MCS− compared with MCS+ group. No significant differences were found in gray matter volume between patient groups. Conclusions. The clinical subcategorization of MCS is supported by differences in brain metabolism but not in gray matter structure, suggesting that brain function in the language network is the main support for recovery of command-following, intelligible verbalization and/or intentional communication in the MCS. Better characterizing the neural correlates of residual cognitive abilities of MCS patients contributes to reduce their misdiagnosis and to adapt therapeutic approaches. © The Author(s) 2020. [less ▲]

Detailed reference viewed: 29 (4 ULiège)
Full Text
See detailBrain-computer interfaces for consciousness assessment and communication in severely brain-injured patients
Annen, Jitka ULiege; Laureys, Steven ULiege; Gosseries, Olivia ULiege

in Millán, José del R.; Ramsey, Nick F. (Eds.) Handbook of Clinical Neurology. Volume 168: Brain-Computer Interfaces (2020)

Patients with disorders of consciousness (DOC) suffer from awareness deficits. Comorbidities such as motor disabilities or visual problems hamper clinical assessments, which can lead to misdiagnosis of ... [more ▼]

Patients with disorders of consciousness (DOC) suffer from awareness deficits. Comorbidities such as motor disabilities or visual problems hamper clinical assessments, which can lead to misdiagnosis of the level of consciousness and render the patient unable to communicate. Objective measures of consciousness can reduce the risk of misdiagnosis and could enable patients to communicate by voluntarily modulating their brain activity. This chapter gives an overview of the literature regarding brain-computer interface (BCI) research in DOC patients. Different auditory, visual, and motor imagery paradigms are discussed, alongside their corresponding advantages and disadvantages. At this point, the use of BCIs for DOC patients in clinical applications is still preliminary. However, perspectives on the improvements in BCIs for DOC patients seem positive, and implementation during rehabilitation shows promise. © 2020 Elsevier B.V. [less ▲]

Detailed reference viewed: 18 (4 ULiège)
Full Text
Peer Reviewed
See detailEuropean Academy of Neurology guideline on the diagnosis of coma and other disorders of consciousness
Kondziella, Daniel; Bender, Andreas; Diserens, Karin et al

in European Journal of Neurology (2020), 27(5), 741-756

Background and purpose: Patients with acquired brain injury and acute or prolonged disorders of consciousness (DoC) are challenging. Evidence to support diagnostic decisions on coma and other DoC is ... [more ▼]

Background and purpose: Patients with acquired brain injury and acute or prolonged disorders of consciousness (DoC) are challenging. Evidence to support diagnostic decisions on coma and other DoC is limited but accumulating. This guideline provides the state-of-the-art evidence regarding the diagnosis of DoC, summarizing data from bedside examination techniques, functional neuroimaging and electroencephalography (EEG). Methods: Sixteen members of the European Academy of Neurology (EAN) Scientific Panel on Coma and Chronic Disorders of Consciousness, representing 10 European countries, reviewed the scientific evidence for the evaluation of coma and other DoC using standard bibliographic measures. Recommendations followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The guideline was endorsed by the EAN. Results: Besides a comprehensive neurological examination, the following suggestions are made: probe for voluntary eye movements using a mirror; repeat clinical assessments in the subacute and chronic setting, using the Coma Recovery Scale – Revised; use the Full Outline of Unresponsiveness score instead of the Glasgow Coma Scale in the acute setting; obtain clinical standard EEG; search for sleep patterns on EEG, particularly rapid eye movement sleep and slow-wave sleep; and, whenever feasible, consider positron emission tomography, resting state functional magnetic resonance imaging (fMRI), active fMRI or EEG paradigms and quantitative analysis of high-density EEG to complement behavioral assessment in patients without command following at the bedside. Conclusions: Standardized clinical evaluation, EEG-based techniques and functional neuroimaging should be integrated for multimodal evaluation of patients with DoC. The state of consciousness should be classified according to the highest level revealed by any of these three approaches. © 2020 European Academy of Neurology [less ▲]

Detailed reference viewed: 72 (1 ULiège)
Full Text
See detailA European survey about needs and beliefs of healthcare and family caregivers regarding pain assessment and management in DOC patients.
Bonin, Estelle ULiege; schnakers, Caroline; Gosseries, Olivia ULiege et al

Poster (2020)

Due to the absence of communication, care for patients with disorders of consciousness (DOC) is an important clinical and ethical issue, especially for pain assessment and management. In this survey we ... [more ▼]

Due to the absence of communication, care for patients with disorders of consciousness (DOC) is an important clinical and ethical issue, especially for pain assessment and management. In this survey we aim to investigate the needs and beliefs of patients’ relatives and caregivers regarding pain assessment and management. By allowing a better understanding of their expectations this study could improve the management of pain in this sensitive population and decrease psychological distress of health professionals, caregivers and families.. To this end we developed an online survey that will be diffused through 40 institutions in Europe involved in the management of DOC patients. ,. The questionnaire will be divided in 2 sections: a first part to collect respondents’ socio-demographic information (e.g., age, gender, country of residence, nationality, religion, current work, year of experience with DOC patient; in compliance with the GDPR regulation) and a second part collecting data to understand the respondents’ knowledge and expectations on pain assessment and management of DOC patients (e.g., questions regarding pain perception in DOC patient, behavioural signs of pain, pain assessment tools, pain treatment). The study will last about 15 minutes and adapted according to the group (i.e., healthcare or family member). Chi-square tests will assess differences between the proportions of answers depending on the following variables: gender, profession, religion, and years of expertise or living with DOC patients. Based on the answers, we aim to develop guidelines to improve pain management and assessments for families and caregivers of DOC patients. [less ▲]

Detailed reference viewed: 53 (1 ULiège)
Full Text
Peer Reviewed
See detailPhenomenology and brain measures during cognitive trance: a case study.
Gosseries, Olivia ULiege; Sombrun, Corine; Thibaut, Aurore ULiege et al

Poster (2019, November 15)

Cognitive trance is a volitional and self-induced modified state of consciousness inherited from shamanic traditional practices that can be practiced by any individual. Little is known about its ... [more ▼]

Cognitive trance is a volitional and self-induced modified state of consciousness inherited from shamanic traditional practices that can be practiced by any individual. Little is known about its phenomenology and neural correlates. We here describe the case of an expert who underwent resting-state EEG, TMS-EEG and FDG-PET during normal wakefulness and cognitive trance. Phenomenological questionnaires were filled after each session. EEG analyses included spectral power and complexity measures. For TMS-evoked potential, diversity index and global mean field power were computed. For PET, global brain metabolism difference between rest and trance was measured. During trance, the participant felt more joy, visual imagery, body image, and an altered experience. She reported higher absorption and dissociation, with five-fold time-scale distortion. Trance was associated with increased spectral power in all frequency bands. Entropy also showed an increase, especially in posterior regions. TMS-EEG showed modifications in cortical reactivity, while PET revealed no significant difference in brain metabolism. Cognitive trance induced a modified state of consciousness characterized by changes in behavior and neurophysiological processes. [less ▲]

Detailed reference viewed: 141 (10 ULiège)
Full Text
Peer Reviewed
See detailMultimodal improvements after apomorphine treatment for chronic disorders of consciousness: preliminary results
Sanz, Leandro ULiege; Lejeune, Nicolas ULiege; Blandiaux, Séverine ULiege et al

Conference (2019, October 24)

Aims: Treatment with apomorphine, a dopamine agonist, has exhibited behavioral effects on the recovery of patients with disorders of consciousness (DOC)[1,2], but its action on brain activity remains ... [more ▼]

Aims: Treatment with apomorphine, a dopamine agonist, has exhibited behavioral effects on the recovery of patients with disorders of consciousness (DOC)[1,2], but its action on brain activity remains unknown. We report the preliminary results of a prospective open-label study using multimodal assessment methods, which aims to confirm the efficacy and investigate the mechanism of apomorphine treatment among post-coma patients. Methods: Three patients with chronic DOC (1 female, 2 males; 47, 34 and 23 years old; 1 hemorrhage, 2 traumatic; 3.5, 4.5 and 3 months since onset) were administered subcutaneous apomorphine for 30 days. They were followed 30 days before initiation, during treatment and 30 days after withdrawal. Outcome measures included Coma Recovery Scale – Revised (CRS-R)[3], positron emission tomography (PET)[4,5] and electroencephalography-based (EEG) measures such as functional connectivity[6] and multivariate machine-learning classification[7,8]. Results: At baseline, patients 1 and 2 were diagnosed with the CRS-R as minimally conscious state (MCS) minus[9,10] (language-independent signs of consciousness), and patient 3 as MCS plus (language-related signs of consciousness). After the initiation of apomorphine, patient 1 improved to MCS plus, patient 2 remained in MCS minus but showed a new sign of consciousness and more consistent behaviors, and patient 3 emerged from the MCS. PET revealed an improvement of global brain metabolism after compared to before apomorphine treatment for all three patients (difference of +43%, +26%, and +4% for patient 1, 2 and 3 respectively). Functional connectivity measured by EEG network centrality also increased after treatment for all patients in the alpha frequency bands. EEG multivariate classifier improved after treatment for two patients (difference of +25%, +20%, -1% for patient 1, 2, and 3 respectively) with significant increase in most individual EEG markers. Conclusion: After treatment, patients showed multimodal improvements with more frequent conscious behaviors and increased brain activity measures compared to baseline observations. These results suggest that the action of apomorphine on the recovery of DOC patients may be associated with measurable neuroimaging changes. Additional results from the subsequent placebo-controlled randomized controlled trial[11] will be necessary to confirm the efficacy and further define the neural effects of apomorphine treatment in severely brain-injured patients. [less ▲]

Detailed reference viewed: 68 (8 ULiège)
Full Text
Peer Reviewed
See detailNeurophenomenology of near-death experience memory in hypnotic recall: a within-subject EEG study
Martial, Charlotte ULiege; Mensen, Armand ULiege; CHARLAND-VERVILLE, Vanessa ULiege et al

in Scientific Reports (2019)

The neurobiological basis of near-death experiences (NDEs) is unknown, but a few studies attempted to investigate it by reproducing in laboratory settings phenomenological experiences that seem to closely ... [more ▼]

The neurobiological basis of near-death experiences (NDEs) is unknown, but a few studies attempted to investigate it by reproducing in laboratory settings phenomenological experiences that seem to closely resemble NDEs. So far, no study has induced NDE-like features via hypnotic modulation while simultaneously measuring changes in brain activity using high-density EEG. Five volunteers who previously had experienced a pleasant NDE were invited to re-experience the NDE memory and another pleasant autobiographical memory (dating to the same time period), in normal consciousness and with hypnosis. We compared the hypnosis-induced subjective experience with the one of the genuine experience memory. Continuous high-density EEG was recorded throughout. At a phenomenological level, we succeeded in recreating NDE-like features without any adverse effects. Absorption and dissociation levels were reported as higher during all hypnosis conditions as compared to normal consciousness conditions, suggesting that our hypnosis-based protocol increased the felt subjective experience in the recall of both memories. The recall of a NDE phenomenology was related to an increase of alpha activity in frontal and posterior regions. This study provides a proof-of-concept methodology for studying the phenomenon, enabling to prospectively explore the NDE-like features and associated EEG changes in controlled settings. [less ▲]

Detailed reference viewed: 76 (13 ULiège)
Peer Reviewed
See detailAutomated Machine Learning-based diagnosis of impaired consciousness: cross-center and protocol generalization of EEG biomarkers.
Raimondo, Federico ULiege; Engemann, Denis; King, Jean-Remi et al

Conference (2019, September 24)

Detailed reference viewed: 51 (3 ULiège)
Full Text
Peer Reviewed
See detailGeneral Anesthesia: A Probe to Explore Consciousness
BONHOMME, Vincent ULiege; STAQUET, Cécile ULiege; Montupil, Javier ULiege et al

in Frontiers in Systems Neuroscience (2019)

Detailed reference viewed: 99 (30 ULiège)
Full Text
Peer Reviewed
See detailDiagnostic accuracy of the CRS-R index in patients with disorders of consciousness
Annen, Jitka ULiege; Filippini, Maria Maddalena; Bonin, Estelle ULiege et al

in Brain Injury (2019), 33(11), 1409-1412

Objective: To obtain a CRS-R index suitable for diagnosis of patients with disorders of consciousness (DOC) and compare it to other CRS-R based scores to evaluate its potential for clinics and research ... [more ▼]

Objective: To obtain a CRS-R index suitable for diagnosis of patients with disorders of consciousness (DOC) and compare it to other CRS-R based scores to evaluate its potential for clinics and research. Design: We evaluated the diagnostic accuracy of several CRS-R-based scores in 124 patients with DOC. ROC analysis of the CRS-R total score, the Rasch-based CRS-R score, CRS-R-MS and the CRS-R index evaluated the diagnostic accuracy for patients with the Unresponsive Wakefulness Syndrome (UWS) and Minimally Conscious State (MCS). Correlations were computed between the CRS-R-MS, CRS-R index, the Rasch-based score and the CRS-R total score. Results: Both the CRS-R-MS and CRS-R index ranged from 0 to 100, with a cut-off of 8.315 that perfectly distinguishes between patients with UWS and MCS. The CRS-R total score and Rasch-based score did not provide a cut-off score for patients with UWS and MCS. The proposed CRS-R index correlated with the CRS-R total score, Rasch-based score and the CRS-R-MS. Conclusion: The CRS-R index is reliable to diagnose patients with UWS and MCS and can be used in compliance with the CRS-R scoring guidelines. The obtained index offers the opportunity to improve the interpretation of clinical assessment and can be used in (longitudinal) research protocols. [less ▲]

Detailed reference viewed: 147 (16 ULiège)
Full Text
Peer Reviewed
See detailGreater preserved baseline functional MRI connectivity in zolpidem responders compared to non-responders in patients with disorders of consciousness.
Ippoliti, Camilla ULiege; Larroque, Stephen Karl ULiege; Sanz, Leandro ULiege et al

Conference (2019, June 30)

Introduction Zolpidem is commonly used as sleep inducer but is one of the few available pharmacological treatments for patients with disorders of consciousness (DOC). Some DOC patients have exhibited ... [more ▼]

Introduction Zolpidem is commonly used as sleep inducer but is one of the few available pharmacological treatments for patients with disorders of consciousness (DOC). Some DOC patients have exhibited paradoxical improvements with zolpidem treatment but the neurological profile of responders remains unclear. No fMRI study has ever been conducted in a group of DOC patients. We investigated the baseline functional brain connectivity in DOC patients responding to zolpidem compared to non-responding patients. Methods Eleven patients in minimally conscious state and 5 who emerged received a 10 mg single dose of zolpidem. Patients were considered responders if a new behaviour was observed using the Coma Recovery Scale-Revised after zolpidem administration. All patients underwent resting-state fMRI (without zolpidem). Hypothesis-free and seed-based region (thalamus) analyses were conducted with age and gender covariates regressed out, comparing patients with 36 healthy volunteers. Results Seven patients qualified as responders (5 sedated, 2 non-sedated) and 9 as non-responders (6 sedated, 3 non-sedated). Hypothesis-free analyses in the sedated group revealed significantly increased intrinsic connectivity among responders in the occipital, occipito-temporal and parieto-occipital areas compared to non-responders. Seed-based analyses showed significantly more preserved positive connectivity of the fronto-insular network in responders compared to non-responders. No significant differences were found between responders and non-responders in the non-sedated condition, possibly due to smaller sample size. Conclusion Our findings suggest a greater preservation of global and local connectivity in zolpidem responders at baseline. Targeting more accurately potential responders to zolpidem can improve the clinical management of DOC patients. [less ▲]

Detailed reference viewed: 92 (9 ULiège)
Full Text
Peer Reviewed
See detailTreating chronic disorders of consciousness with apomorphine: preliminary results of a multimodal clinical trial
Sanz, Leandro ULiege; Lejeune, Nicolas ULiege; Blandiaux, Séverine ULiege et al

Poster (2019, June 29)

Background and aims: Treatment with apomorphine, a dopamine agonist, has exhibited promising effects on the recovery of patients with disorders of consciousness (DOC) due to traumatic brain injury. This ... [more ▼]

Background and aims: Treatment with apomorphine, a dopamine agonist, has exhibited promising effects on the recovery of patients with disorders of consciousness (DOC) due to traumatic brain injury. This prospective open-label clinical trial aims to confirm its efficacy and investigate its action on brain activity. Methods: Patients with chronic DOC were administered subcutaneous apomorphine for 30 days. They were monitored 30 days before initiation, during treatment and 30 days after withdrawal. Outcome measures included Coma Recovery Scale – Revised (CRS-R), actigraphy, positron emission tomography (PET) and electroencephalography-based (EEG) metrics such as network centrality and a multivariate machine-learning classifier. Results: A 47-year-old woman in an unresponsive wakefulness state (UWS) due to a ruptured aneurysm underwent apomorphine treatment. CRS-R indicated a minimally conscious state (MCS) diagnosis in 1/9 assessment before treatment, increasing to 6/8 during treatment, and 4/5 after withdrawal (Fig.1). Actigraphy showed higher mean activity and normalised power after treatment. Compared to healthy controls, PET whole-brain metabolism revealed a 59% metabolic decrease before treatment and 51% after, with significant increases in right cortical areas. (Fig.2) EEG multivariate classifier corresponded to UWS before treatment and MCS after, with significant increase in most individual markers. Functional connectivity measured by network centrality increased predominantly in alpha frequency after treatment. (Fig.3) Conclusion: After treatment, this patient showed multimodal improvements with more frequent conscious behaviours and increased brain activity measures. These results suggest that the action of apomorphine on the recovery of DOC patients may be associated with measurable neuroimaging changes. Results of two subsequently treated patients will be reported. Clinical trial identifiers: EudraCT 2018-003144-23; Clinicaltrials.gov NCT03623828 [less ▲]

Detailed reference viewed: 71 (17 ULiège)
Full Text
Peer Reviewed
See detailBrain functional network segregation and integration in patients with disorders of consciousness
Panda, Rajanikant ULiege; Annen, Jitka ULiege; Gosseries, Olivia ULiege et al

Conference (2019, June 10)

Introduction: The brain regulates information flow by balancing integration and segregation of networks to facilitate flexible cognition and behavior. However, it is unclear how this mechanism manifests ... [more ▼]

Introduction: The brain regulates information flow by balancing integration and segregation of networks to facilitate flexible cognition and behavior. However, it is unclear how this mechanism manifests during loss of consciousness [1-3]. In this study, we studied brain network segregation and integration using resting state functional magnetic resonance imaging (fMRI) data to assess brain networks in patients with disorders of consciousness. Methods: Fifty-four patients with disorders of consciousness (24 unresponsive wakefulness syndrome (UWS) (M:F=16:8; mean age= 45±13), 30 minimally conscious state (MCS) (M:F=23:7; mean age= 36±14) and 30 age- and gender-matched healthy controls underwent fMRI. The resting-state MRI data were acquired during wakefulness with eyes closed using a 3 Tesla MRI scanner. Additionally a T1-weighted, structural imaging was performed for anatomical coregistration. First, the fMRI data were pre-processed for realignment, co-registration, segmentation, normalization, head motion regressed out and 0.01-0.1Hz band pass filtered. Data were then parcellated in 256 brain regions (ROIs) using Shen functional atlas from [4]. The connectivity matrix was computed using Pearson correlation. Graph theory connectivity was carried out to measure brain network topological properties in terms of network segregation and integration by computing binarized undirected connectivity matrix. Normalized clustering coefficients were computed as measures of network segregation while normalized participation coefficients were computed as measures of network integration [3]. Through integrated nodal graph measures, individual networks (such as default mode, frontoparietal, auditory, salience, subcortical and cerebellum networks) were also computed to study which networks were predominantly affected [3]. To enable comparison of network properties across groups, we used sparsity-based threshold (S) to avoid spurious results. To prevent biases associated with a single threshold, we determined a range of sparsity (0.06 ≤ S ≤ 0.5, with an increment of 0.025), which avoids excess network fragmentation at sparser thresholds. The between group differences for global (i.e., whole brain) and individual networks were computed with unpaired t-test with FDR correction for multiple comparison [5-6]. Finally the network segregation and integration mean values were correlated with Coma Recovery Scale-Revised (CRS-R) modified score [7]. Results: Patients in UWS had decreased participation coefficients (network integration) compared to those in MCS (effect size= -0.44, p<0.0001) and controls (effect size= -0.63, p<0.0001). Patients in MCS had significant decreased participation coefficients compared to controls (effect size= -0.37, p<0.001). On the other hand, patients in UWS had significant increased clustering coefficient (network segregation) compared to those in MCS (effect size= 0.39, p= <0.001) and controls (effect size= 0.63, p<0.0001). Patients in MCS had significant increased clustering coefficients compared to controls (effect size= 0.03, p<0.01). This decreased participation coefficient and increased clustering coefficient were noted predominantly observed in the frontoparietal and subcortical networks. Conclusions: Patients with disorders of consciousness present decreased in network integration and increased in network segregation. Notably, fragmentation of network integration is observed in patients in unaware patients (UWS), which indicates impaired information flow in the brain modules, especially in the frontoparietal and subcortical networks. This introduces a potential measure to classify patients with disorders of consciousness, which could ultimately be used for clinical diagnosis. Reference: 1. Fukushima, M., (2018). Structure–function relationships during segregated and integrated network states of human brain functional connectivity. Brain Structure and Function, 223(3), 1091-1106. 2. Deco, G., (2015). Rethinking segregation and integration: contributions of whole-brain modelling. Nature Reviews Neuroscience, 16(7), 430. 3. Keerativittayayut, R., (2018). Large-scale network integration in the human brain tracks temporal uctuations in memory encoding performance. eLife, 7, e32696. 4. Finn, E. S., (2015). Functional connectome ngerprinting: identifying individuals using patterns of brain connectivity. Nature neuroscience, 18(11), 1664. 5. Holla, B., (2017). Disrupted resting brain graph measures in individuals at high risk for alcoholism. Psychiatry Research: Neuroimaging, 265, 54-64. 6. Chennu, S., (2017). Brain networks predict metabolism, diagnosis and prognosis at the bedside in disorders of consciousness. Brain, 140(8), 2120-2132. 7. Demertzi, A., (2015). Intrinsic functional connectivity differentiates minimally conscious from unresponsive patients. Brain, 138(9), 2619-2631. [less ▲]

Detailed reference viewed: 134 (14 ULiège)