References of "Vanhaudenhuyse, Audrey"
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See detailCorrelation between resting state fMRI total neuronal activity and PET metabolism in healthy controls and patients with disorders of consciousness
Soddu, Andrea ULiege; Gomez, Francisco; Heine, Lizette ULiege et al

in Brain and Behavior (2016), 6(1), 1-15

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made ... [more ▼]

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made it possible to assess changes in metabolic activity in clinical applications, such as the study of severe brain injury and disorders of consciousness. Objective: We assessed the possi- bility of creating functional MRI activity maps, which could estimate the rela- tive levels of activity in FDG-PET cerebral metabolic maps. If no metabolic absolute measures can be extracted, our approach may still be of clinical use in centers without access to FDG-PET. It also overcomes the problem of recogniz- ing individual networks of independent component selection in functional mag- netic resonance imaging (fMRI) resting state analysis. Methods: We extracted resting state fMRI functional connectivity maps using independent component analysis and combined only components of neuronal origin. To assess neu- ronality of components a classification based on support vector machine (SVM) was used. We compared the generated maps with the FDG-PET maps in 16 healthy controls, 11 vegetative state/unresponsive wakefulness syndrome patients and four locked-in patients. Results: The results show a significant similarity with q = 0.75  0.05 for healthy controls and q = 0.58  0.09 for vegetative state/unresponsive wakefulness syndrome patients between the FDG- PET and the fMRI based maps. FDG-PET, fMRI neuronal maps, and the conjunction analysis show decreases in frontoparietal and medial regions in vegetative patients with respect to controls. Subsequent analysis in locked-in syndrome patients produced also consistent maps with healthy controls. Conclusions: The constructed resting state fMRI functional connectivity map points toward the possibility for fMRI resting state to estimate relative levels of activity in a metabolic map. [less ▲]

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See detailEvaluation clinique des états de conscience altérée
VANHAUDENHUYSE, Audrey ULiege

Conference (2015, November 26)

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See detailCerebral functional connectivity periodically (de)synchronizes with anatomical constraints
Liegeois, Raphaël ULiege; Ziegler, Erik; Bahri, Mohamed Ali ULiege et al

in Brain Structure and Function (2015)

This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber ... [more ▼]

This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of the fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber tractography. Instead of a static analysis based on the correlation between SC and the FC averaged over the entire fMRI time series, we propose a dynamic analysis, based on the time evolution of the correlation between SC and a suitably windowed FC. Assessing the statistical significance of the time series against random phase permutations, our data show a pronounced peak of significance for time window widths around 20-30 TR (40-60 sec). Using the appropriate window width, we show that FC patterns oscillate between phases of high modularity, primarily shaped by anatomy, and phases of low modularity, primarily shaped by inter-network connectivity. Building upon recent results in dynamic FC, this emphasizes the potential role of SC as a transitory architecture between different highly connected resting state FC patterns. Finally, we show that networks implied in consciousness-related processes, such as the default mode network (DMN), contribute more to these brain-level fluctuations compared to other networks, such as the motor or somatosensory networks. This suggests that the fluctuations between FC and SC are capturing mind-wandering effects. [less ▲]

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See detailHypnose et recherche
VANHAUDENHUYSE, Audrey ULiege

Conference (2015, May 13)

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See detailIntrinsic fMRI functional architecture differentiates single patients after severe brain injury
Demertzi, Athina ULiege; Antonopoulos, Georgios ULiege; Heine, Lizette ULiege et al

Poster (2015)

Background: Resting state acquisitions are by definition appropriate to assess non-communicating subjects. We here assessed the clinical relevance of systems-level resting state fMRI in patients with ... [more ▼]

Background: Resting state acquisitions are by definition appropriate to assess non-communicating subjects. We here assessed the clinical relevance of systems-level resting state fMRI in patients with disorders of consciousness with the aim to promote single-patient diagnostics. Methods: Seventy three patients in minimally conscious state (MCS), vegetative state/unresponsive wakefulness syndrome (VS/UWS) and coma were scanned in 3 different centers. The main analysis was performed on the dataset coming from one centre (Liège, 51 patients; 26 MCS, 19 VS/UWS, 6 coma; 16 traumatic, 32 non-traumatic, 3 mixed; 35 patients assessed >1 month post-insult) for whom the clinical diagnosis with the Coma Recovery Scale-Revised (CRS-R) was congruent with positron emission tomography scanning. Using a multiple-seed correlation approach, group-level functional connectivity was investigated for the default mode, frontoparietal, salience, auditory, sensorimotor and visual networks. Between-group inferential statistics and machine learning were used to identify each network’s capacity to discriminate between patients in MCS and VS/UWS. Data from 22 patients independently scanned in two other centres (Salzburg: 10 MCS, 5 VS/UWS; New York: 5 MCS, 1 VS/UWS, 1 emerged from MCS) were used to validate the classification with the indetified features. Results: CRS-R total scores correlated with key regions of each network reflecting their involvement in consciousness-related processes. Although all networks had a high discriminative capacity (>80%) for separating patients in MCS and VS/UWS, the auditory network was ranked the most highly. Specifically, bilateral auditory and visual cortices of the auditory network were more functionally connected in patients in MCS compared to VS/UWS. Connectivity values in these three regions discriminated congruently 20 out of 22 independently assessed patients. Conclusions: These findings highlight the significance of preserved multisensory integration and top-down processing in minimal consciousness which are seemingly supported by auditory-visual crossmodal connectivity, and promote the clinical utility of the resting paradigm for single-patient diagnostics. [less ▲]

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See detailThalamic volume as a biomarker for Disorders Of Consciousness. Progress in Biomedical Optics and Imaging
Rubeaux, M; Mahalingam, J; Gomez, F et al

in Proceedings of SPIE (2015)

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See detailHypnosis modulates behavioural measures and subjective ratings about external and internal awareness
Demertzi, Athina ULiege; VANHAUDENHUYSE, Audrey ULiege; Noirhomme, Quentin ULiege et al

in Journal of Physiology - Paris (2015), 109(4), 173-179

In altered subjective states, the behavioural quantification of external and internal awareness remains challenging due to the need for reports on the subjects’ behalf. With the aim to characterize the ... [more ▼]

In altered subjective states, the behavioural quantification of external and internal awareness remains challenging due to the need for reports on the subjects’ behalf. With the aim to characterize the behavioural counterpart of external and internal awareness in a modified subjective condition, we used hypnosis during which subjects remain fully responsive. Eleven right-handed subjects reached a satisfactory level of hypnotisability as evidenced by subjective reports on arousal, absorption and dissociation. Compared to normal wakefulness, in hypnosis (a) participants’ self-ratings for internal awareness increased and self-ratings for external awareness decreased, (b) the two awareness components tended to anticorrelate less and the switches between external and internal awareness self-ratings were less frequent, and (c) participants’ reaction times were higher and lapses in key presses were more frequent. The identified imbalance between the two components of awareness is considered as of functional relevance to subjective (meta)cognition, possibly mediated by allocated attentional properties brought about by hypnosis. Our results highlight the presence of a cognitive counterpart in resting state, indicate that the modified contents of awareness are measurable behaviourally, and provide leverage for investigations of more challenging altered conscious states, such as anaesthesia, sleep and disorders of consciousness. [less ▲]

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See detailThe use of hypnosis in healthcare
VANHAUDENHUYSE, Audrey ULiege; FAYMONVILLE, Marie-Elisabeth ULiege

in Revue du Praticien (La) (2015), 65(4), 457-459

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See detailHypnosis and pain modulation.
VANHAUDENHUYSE, Audrey ULiege; Gillet, Aline ULiege; NYSSEN, Anne-Sophie ULiege et al

in Garcia-Larrea, Luis; Jackson, PL (Eds.) Pain in the Conscious Brain (2015)

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See detailEfficacy and cost-effectiveness: A study of different treatment approaches in a tertiary pain centre
VANHAUDENHUYSE, Audrey ULiege; Gillet, Aline ULiege; MALAISE, Nicole ULiege et al

in European Journal of Pain (London, England) (2015)

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See detailSwallowing in disorders of consciousness
Bicego, Aminata; Lejoly, Kelly ULiege; Maudoux, Audrey et al

in Revue Neurologique (2014), 170(10),

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See detailNeurophysiology of hypnosis
VANHAUDENHUYSE, Audrey ULiege; Laureys, Steven ULiege; Faymonville, Marie-Elisabeth ULiege

in Clinical Neurophysiology (2014), 44

We here review behavioral, neuroimaging and electrophysiological studies of hypnosis as a state, as well as hypnosis as a tool to modulate brain responses to painful stimulations. Studies have shown that ... [more ▼]

We here review behavioral, neuroimaging and electrophysiological studies of hypnosis as a state, as well as hypnosis as a tool to modulate brain responses to painful stimulations. Studies have shown that hypnotic processes modify internal (self awareness) as well as external (environmental awareness) brain networks. Brain mechanisms underlying the modulation of pain perception under hypnotic conditions involve cortical as well as subcortical areas including anterior cingulate and prefrontal cortices, basal ganglia and thalami. Combined with local anesthesia and conscious sedation in patients undergoing surgery, hypnosis is associated with improved peri- and postoperative comfort of patients and surgeons. Finally, hypnosis can be considered as a useful analogue for simulating conversion and dissociation symptoms in healthy subjects, permitting better characterization of these challenging disorders by producing clinically similar experiences. [less ▲]

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See detailPosterior Cingulate Cortex-Related Co-Activation Patterns: A Resting State fMRI Study in Propofol-Induced Loss of Consciousness
Amico, Enrico ULiege; Gomez, Francisco; Di Perri, Carol et al

in PLoS ONE (2014), 9

Background: Recent studies have been shown that functional connectivity of cerebral areas is not a static phenomenon, but exhibits spontaneous fluctuations over time. There is evidence that fluctuating ... [more ▼]

Background: Recent studies have been shown that functional connectivity of cerebral areas is not a static phenomenon, but exhibits spontaneous fluctuations over time. There is evidence that fluctuating connectivity is an intrinsic phenomenon of brain dynamics that persists during anesthesia. Lately, point process analysis applied on functional data has revealed that much of the information regarding brain connectivity is contained in a fraction of critical time points of a resting state dataset. In the present study we want to extend this methodology for the investigation of resting state fMRI spatial pattern changes during propofol-induced modulation of consciousness, with the aim of extracting new insights on brain networks consciousness-dependent fluctuations. Methods: Resting-state fMRI volumes on 18 healthy subjects were acquired in four clinical states during propofol injection: wakefulness, sedation, unconsciousness, and recovery. The dataset was reduced to a spatio-temporal point process by selecting time points in the Posterior Cingulate Cortex (PCC) at which the signal is higher than a given threshold (i.e., BOLD intensity above 1 standard deviation). Spatial clustering on the PCC time frames extracted was then performed (number of clusters = 8), to obtain 8 different PCC co-activation patterns (CAPs) for each level of consciousness. Results: The current analysis shows that the core of the PCC-CAPs throughout consciousness modulation seems to be preserved. Nonetheless, this methodology enables to differentiate region-specific propofol-induced reductions in PCC-CAPs, some of them already present in the functional connectivity literature (e.g., disconnections of the prefrontal cortex, thalamus, auditory cortex), some others new (e.g., reduced co-activation in motor cortex and visual area). Conclusion: In conclusion, our results indicate that the employed methodology can help in improving and refining the characterization of local functional changes in the brain associated to propofol-induced modulation of consciousness. [less ▲]

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See detailWhite Matter Changes in Comatose Survivors of Anoxic Ischemic Encephalopathy and Traumatic Brain Injury: Comparative Diffusion-Tensor Imaging Study
Van Der Eerden, Anke; Khalilzadeh, Omid; Perlbarg, Vincent et al

in Radiology (2014), 270

Purpose:To analyze white matter pathologic abnormalities by using diffusion-tensor (DT) imaging in a multicenter prospective cohort of comatose patients following cardiac arrest or traumatic brain injury ... [more ▼]

Purpose:To analyze white matter pathologic abnormalities by using diffusion-tensor (DT) imaging in a multicenter prospective cohort of comatose patients following cardiac arrest or traumatic brain injury (TBI). Materials and Methods: Institutional review board approval and informed consent from proxies and control subjects were obtained. DT imaging was performed 5–57 days after insult in 49 cardiac arrest and 40 TBI patients. To control for DT imaging–processing variability, patients’ values were normalized to those of 111 control subjects. Automated segmentation software calculated normalized axial diffusivity (λ1) and radial diffusivity (λ) in 19 predefined white matter regions of interest (ROIs). DT imaging variables were compared by using general linear modeling, and side-to-side Pearson correlation coefficients were calculated. P values were corrected for multiple testing (Bonferroni). Results:In central white matter, λ1 differed from that in control subjects in six of seven TBI ROIs and five of seven cardiac arrest ROIs (all P < .01). The λ differed from that in control subjects in all ROIs in both patient groups (P < .01). In hemispheres, λ1 was decreased compared with that in control subjects in three of 12 TBI ROIs (P < .05) and nine of 12 cardiac arrest ROIs (P < .01). The λ was increased in all TBI ROIs (P < .01) and in seven of 12 cardiac arrest ROIs (P < .05). Cerebral hemisphere λ1 was lower in cardiac arrest than in TBI in six of 12 ROIs (P < .01), while λ was higher in TBI than in cardiac arrest in eight of 12 ROIs (P < .01). Diffusivity values were symmetrically distributed in cardiac arrest (P < .001 for side-to-side correlation) but not in TBI patients. Conclusion:DT imaging findings are consistent with the known predominance of cerebral hemisphere axonal injury in cardiac arrest and chiefly central myelin injury in TBI. This consistency supports the validity of DT imaging for differentiating axon and myelin damage in vivo in humans. [less ▲]

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See detailEffect of zolpidem in chronic disorders of consciousness: a prospective open-label study.
Thonnard, Marie ULiege; Gosseries, Olivia ULiege; Demertzi, Athina ULiege et al

in Functional Neurology (2014), 28(4), 259-64

Zolpidem has been reported as an "awakening drug" in some patients with disorders of consciousness (DOC). We here present the results of a prospective openlabel study in chronic DOC patients. Sixty ... [more ▼]

Zolpidem has been reported as an "awakening drug" in some patients with disorders of consciousness (DOC). We here present the results of a prospective openlabel study in chronic DOC patients. Sixty patients (35±15 years; 18 females; mean time since insult ± SD: 4±5.5 years; 31 with traumatic etiology) with a diagnosis of vegetative state/unresponsive wakefulness syndrome (n=28) or minimally conscious state (n=32) were behaviorally assessed using the Coma Recovery Scale-Revised (CRS-R) before and one hour after administration of 10 mg of zolpidem. At the group level, the diagnosis did not change after intake of zolpidem (p=0.10) and CRS-R total scores decreased (p=0.01). Twelve patients (20%) showed improved behaviors and/or CRS-R total scores after zolpidem administration but in only one patient was the diagnosis after zolpidem intake found to show a significant improvement (functional object use), which suggested a change of diagnosis. However, in this patient, a double-blind placebo-controlled trial was performed in order to better specify the effects of zolpidem, but the patient, on this trial, failed to show any clinical improvements. The present open-label study therefore failed to show any clinically significant improvement (i.e., change of Effect of zolpidem in chronic disorders of consciousness: a prospective open-label study diagnosis) in any of the 60 studied chronic DOC patients. [less ▲]

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