Caroline Schnakers

University of Liège | ulg · Cyclotron Research Centre

Traditionally, neuroimaging studies of post-stroke aphasia focus on supratentorial brain regions related to language function and recovery. However, stroke-induced lesions often distort these areas, posing a challenge for neuroimaging analyses aimed at identifying reliable biomarkers. This study seeks to explore alternative biomarkers in regions le...

Objective: In this study we explored how neuroimaging and blood biomarkers relate to cognitive recovery in traumatic brain injury (TBI) patients. Methods: Sixteen participants with moderate to severe traumatic brain injury (TBI) were enrolled, with blood samples, MRI, and diffusion tensor imaging (DTI) collected at enrollment and six months. The Re...

Understanding the neural signatures of consciousness and the mechanisms underlying its disorders, such as coma and unresponsive wakefulness syndrome, remains a critical challenge in neuroscience. In this study, we present a novel computational approach for the in silico discovery of neural correlates of consciousness, the mechanisms driving its dis...

Background/Objectives: Persons with disorders of consciousness (DoCs) may perceive pain without being able to communicate their discomfort. The Nociception Coma Scale (NCS) and its revised form (NCS-R) have been proposed to assess nociception in persons with DoCs. The main aim of this international multicenter study was to confirm (or not) our prel...

Background The cerebellum has emerged as a potential target for transcranial direct current stimulation (tDCS) in post-stroke aphasia (PSA) due to its role in language processing and relative preservation compared to supratentorial lesions. Recent evidence also highlights the cerebellum's involvement in affective and social processes, suggesting po...

This poster aims at presenting the main goals of the Iberian Observatory for Disorders of Consciousness and what the developers intend to do to ensure the success of this international project. The high rate of misdiagnosis for people with disorders of consciousness (DoC) is well known and widely reported in the literature. Most of these studies ha...

Behavioral assessment remains the critical modality for the detection of signs of consciousness and, hence, for identifying states of altered consciousness after brain injury. However, because of the presence of confounding factors such as severe functional, motoric and cognitive impairment, accurate diagnosis is a challenging enterprise, leading t...

As illustrated in the previous chapters, the clinical management of disorders of consciousness remains very difficult, but technological advances in neuroimaging, in EEG-based brain–computer interfaces and in treatments, are now offering new ways to improve the diagnostic, prognostic, and therapeutic management of these challenging conditions. In t...

Over the past 30 years, there have been significant advances in the understanding of the mechanisms associated with loss and recovery of consciousness following severe brain injury. This work has provided a strong grounding for the development of novel restorative therapeutic interventions. Although all interventions are aimed at modulating and the...

Background. Over the past thirty years, there have been significant advances in the understanding of the mechanisms associated with loss and recovery of consciousness following severe brain injury. This work has provided a strong grounding for the development of novel restorative therapeutic interventions. While all interventions are aimed at modul...

The recent publication of practice guidelines for management of patients with disorders of consciousness (DoC) in the United States and Europe was a major step forward in improving the accuracy and consistency of terminology, diagnostic criteria, and prognostication in this population. There remains a pressing need for a more precise brain injury c...

The implementation of multimodality monitoring in the clinical management of patients with disorders of consciousness (DoC) results in physiological measurements that can be collected in a continuous and regular fashion or even at waveform resolution. Such data are considered part of the “Big Data” available in intensive care units and are potentia...

Background Treatments aimed at hastening recovery from disorders of consciousness (DOC; e.g., coma, the vegetative state) have lagged behind a rapidly advancing science of these conditions. In part, this is due to the difficulty in selectively targeting the many deep regions of the brain known to be key for recovery from DOC. The (re)emergence of l...

Background: Patients with disorders of consciousness who are behaviorally unresponsive may demonstrate volitional brain responses to motor imagery or motor commands detectable on functional magnetic resonance imaging or electroencephalography. This state of cognitive motor dissociation (CMD) may have prognostic significance. Methods: The Neurocr...

Background Transcranial direct current stimulation (tDCS) combined with speech and language therapy (SLT) may increase the effectiveness of recovery in post-stroke aphasia. However, inconsistent responses have been observed, in part due to small sample sizes, limited comprehensive assessments, and poor mechanistic understanding of intervention rela...

Background. Many patients with severe brain damage may survive and remain in a prolonged disorder of consciousness (PDoC), impacting the quality of life (QoL) and needs of their family caregivers. However, the current literature on the factors influencing these needs is contradictory. We aim to describe the needs, QoL, and emotional distress of car...

Prognosis of prolonged Disorders of Consciousness (pDoC) is influenced by patients' clinical diagnosis and Coma Recovery Scale-Revised (CRS-R) total score. We compared the prognostic accuracy of a novel Consciousness Domain Index (CDI) with that of clinical diagnosis and CRS-R total score, for recovery of full consciousness at 6-, 12-, and 24-month...

Research Objectives To investigate how spasticity developed in patients diagnosed with a prolonged DOC over almost a two-year observation period (21months) and how it related to the patients’ age, gender, time since injury, etiology, level of consciousness, and anti-spastic medications. Design Retrospective study. Setting Long-term care facility...

Research Objectives To assess whether demographic and clinical factors might impact sleep quality during inpatient stay in a rehabilitation setting. Design In this prospective study, patients were assessed for their sleep quality at admission and discharge. Setting Patients admitted in the acute inpatient rehabilitation unit of Casa Colina Hospit...

The assessment of residual language abilities in patients with disorders of consciousness (DoC) after severe brain injury is particularly challenging due to their limited behavioral repertoire. Moreover, associated language impairment such as receptive aphasia may lead to an underestimation of actual consciousness levels. In this review, we examine...

The promotion of recovery in patients who have entered a disorder of consciousness (DOC; e.g., coma or vegetative states) following severe brain injury remains an enduring medical challenge despite an ever-growing scientific understanding of these conditions. Indeed, recent work has consistently implicated altered cortical modulation by deep brain...

Objectives: In this retrospective study, we investigated how spasticity developed in patients diagnosed with a prolonged DOC over an almost two-year observation period (21 months), and how it related to the patients' age, gender, time since injury, etiology, level of consciousness, and anti-spastic medications. Methods: In total, 19 patients wit...

Background. Patients with prolonged disorders of consciousness (pDoC) have a high mortality rate due to medical complications. Since an accurate prognosis is essential for decision-making on patients’ management, we analysed data from an international multicentre prospective cohort study to evaluate two-year mortality rate and bedside predictors of...

Objective: Transcranial Focused Ultrasound (tFUS) is a promising new potential neuromodulation tool. However, the safety of tFUS neuromodulation has not yet been assessed adequately. Patients with refractory temporal lobe epilepsy electing to undergo an anterior temporal lobe resection present a unique opportunity to evaluate the safety and effica...

The American Academy of Neurology and the European Academy of Neurology have now recognized, for the very first time, the value of advanced neuroimaging and electrophysiology techniques (AIEs) in the context of diagnosing patients with a disorder of consciousness (DOC). This recognition is part of an important agenda of promoting evidence-based com...

Objectives: This longitudinal study aims at 1) providing preliminary evidence of changes in blood-based biomarkers across time in chronic TBI and 2) relating these changes to outcome measures and cerebral structure and activity. Methods: Eight patients with moderate-to-severe TBI (7 males, 35 ± 7.6 years old, 5 severe TBI, 17.52 ± 3.84 months post-...

Covert cognition in patients with disorders of consciousness represents a real diagnostic conundrum for clinicians. In this meta-analysis, our main objective was to identify clinical and demographic variables that are more likely to be associated with responding to an active paradigm. Among 2018 citations found on PubMed, 60 observational studies w...

Background: The incidence of traumatic brain injury (TBI) in the U.S. has been estimated at 1.7 million people each year and results in $60 billion in medical and productivity costs. A TBI can result in severe and potentially chronic cognitive and physical deficits. There has been an increased focus on the use of neurologic biomarkers for both moni...

The analysis of spontaneous EEG activity and evoked potentials is a cornerstone of the instrumental evaluation of patients with disorders of consciousness (DoC). The past few years have witnessed an unprecedented surge in EEG-related research applied to the prediction and detection of recovery of consciousness after severe brain injury, opening up...

Introduction New guidelines regarding the diagnosis of disorders of consciousness (DOC) (such as vegetative state and minimally conscious state) have recently been published by the American Academy of Neurology and the European Academy of Neurology. This follows an impressive number of prospective studies performed on DOC and recent multi-centric s...

Objective This international multi-center, prospective, observational study aimed at identifying predictors of short-term clinical outcome in patients with prolonged Disorders of Consciousness (DoC) due to acquired severe brain injury. Methods Patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (...

Objective: Low-Intensity Focused Ultrasound Pulsations (LIFUP) is a promising new potential neuromodulation tool. However, the safety of LIFUP neuromodulation has not yet been adequately assessed. Patients with refractory temporal lobe epilepsy electing to undergo an anterior temporal lobe resection present a unique opportunity to evaluate the safe...

Disorders of consciousness (DOCs), including vegetative and minimally conscious states, represent a financial, medical and ethical conundrum. Recently published guidelines for the diagnosis, prognosis and treatment of DOCs should lead us to reconsider our management strategies for these challenging disorders.

The assessment of the consciousness level of Unresponsive Wakefulness Syndrome (UWS) patients often depends on a subjective interpretation of the observed spontaneous and volitional behavior. To date, the misdiagnosis level is around 30%. The aim of this study was to observe the behavior of UWS patients, during the administration of noxious stimula...

Background Little is known about the changes in blood-based biomarkers and their relation to outcome, years after TBI. This prospective study aims to provide preliminary evidence of longitudinal changes blood-based biomarkers that relate to changes in outcome measures and cerebral structure and activity. Methods Eight patients with moderate-to-seve...

The Nociception Coma Scale-Revised (NCS-R) was developed to help assess pain in patients with disorders of consciousness (DOC). Several studies have shown its sensitivity in assessing response to acute noxious stimuli. However, they failed to determine a reliable cut-off score that could be used to infer pain processing in these patients. This retr...

Background The accurate assessment of patients with disorders of consciousness (DOC) is a challenge to most experienced clinicians. As a potential clinical tool, functional magnetic resonance imaging (fMRI) could detect residual awareness without the need for the patients’ actual motor responses. Methods We adopted a simple active fMRI motor parad...

A significant number of critically ill neurological and neurosurgical patients are still managed in the medical or surgical ICU by non-neurointensivists, who have a hard time appreciating the delicate needs of these patients. This dynamic guide reviews current topics facing neurocritical care providers in a straight-forward, structured, and practic...

To date, no international guidelines or recommendations for diagnosis or prognosis of patients with disorders of consciousness (DoC) have been established. The International Brain Injury Association’s (IBIA) Special Interest Group on Disorders of Consciousness (DoC-SIG) launched an international multicenter survey to compare diagnostic and prognost...

Primary Objective: This study aims to validate the Chinese version of the Coma Recovery Scale-Revised (CRS-R). Methods: One hundred sixty-nine patients were assessed with both the CRS-R and the Glasgow Coma Scale (GCS), diagnosed as being in unresponsive wakefulness syndrome (UWS, formerly known as vegetative state), minimally conscious state (MCS)...

Aims: 1. to investigate diagnostic and prognostic procedures routinely used by international professionals to assess children with disorders of consciousness (DoC); 2. to explore use and availability of internal and national guidelines for pediatric DoC; 3. to identify international differences in diagnostic/prognostic protocols. Methods: The Inter...

Diagnostic accuracy and reliable assessment of prognosis are challenging in patients in vegetative state (VS) and in minimally conscious state (MCS). This longitudinal multi-centric study aims to identify neurophysiological patterns with diagnostic and prognostic value. 59 patients in VS and 63 in MCS underwent clinical assessment by Coma Recovery...

Objectives: Considering sensory stimulation programs (SSP) as a treatment for disorders of consciousness is still debated today. Previous studies investigating its efficacy were affected by various biases among which small sample size and spontaneous recovery. In this study, treatment-related changes were assessed using time-series design in patien...

Context Heart rate variability (HRV) is thought to reflect the affective and physiological aspects of pain and is emerging as a possible descriptor of the functional brain organization contributing to homeostasis. Objectives To investigate whether the short-term Complexity Index (CIs; short-term Complexity Index), a measure of HRV complexity, is...

Taking care of patients recovering from coma is challenging, with current therapeutic treatments being neither well developed nor well validated. Sensory stimulation is a long-established treatment developed for severely brain-injured patients. Numerous studies have investigated the use of sensory stimulation programs in patients with disorders of...

This revised and expanded second edition discusses the assessment and treatment of patients recovering from coma and disorders of consciousness. Besides diagnostic, prognostic and ethical issues, this book describes well-established techniques and procedures, and also techniques under development. New chapters include consciousness theories, issues...

Recent advances in functional neuroimaging have demonstrated novel potential for informing diagnosis and prognosis in the unresponsive wakeful syndrome and minimally conscious states. However, these technologies come with considerable expense and difficulty, limiting the possibility of wider clinical application in patients. Here, we show that high...

Predicting outcome in the early phase after severe traumatic brain injury (sTBI) is a major clinical challenge, particularly identifying patients with potential of good cognitive outcome. The current single center prospective study aimed to explore presence and normalization of electroencephalography (EEG)-based event related potentials (ERPs) in t...

Different behavioural signs of consciousness can distinguish patients with an unresponsive wakefulness syndrome from patients in minimally conscious state (MCS). The Coma Recovery Scale-Revised (CRS-R) is the most sensitive scale to differentiate the different altered states of consciousness and eleven items detect the MCS. The aim of this study is...

Background: Misdiagnosis rate is high in patients with disorders of consciousness, potentially leading to an inappropriate clinical management of these patients. Sensitive standardised rating scales offer some protections from these diagnostic errors. In this context, the use of the Coma Recovery Scale-Revised (CRS-R) has strongly been recommended...

The minimally conscious state (MCS) is a condition of severely altered consciousness that is distinguished from the vegetative state (VS) by the presence of minimal but clearly discernible behavioral evidence of self or environmental awareness. There is increasing evidence from neurobehavioral and neuroimaging studies that important differences in...

Objective: To investigate the diagnostic utility of electrophysiological recordings during active cognitive tasks in detecting residual cognitive capacities in patients with disorders of consciousness (DoC) after severe acquired brain injury. Design: Systematic review of empirical research in MEDLINE, Embase, PsycINFO, and Cochrane from January...

Objective: To propose a new methodology based on single-trial analysis for detecting residual response to command with EMG in patients with disorders of consciousness (DOC), overcoming the issue of trial dependency and decreasing the influence of a patient's fluctuation of vigilance or arousal over time on diagnostic accuracy. Methods: Forty-fiv...

Until now, the main way to assess whether a patient is conscious or not is to observe what he can do spontaneously or in response to stimulation. Although there is a growing body of research on the subject, detecting oriented/voluntary responses is still extremely challenging. Motor, verbal, and cognitive impairments; fluctuations of vigilance; and...

. The diagnostic usefulness of electrophysiological methods in assessing disorders of consciousness (DoC) remains to be established on an individual patient level, and there is need to determine what constitutes robust experimental paradigm to elicit electrophysiological indices of covert cognitive capacity. Objectives . Two tasks encompassing acti...

The diagnosis of patients with Disorders Of Consciousness represents a challenge in the clinical routine. Recently, Brain Computer Interfaces based in Electroencephalography (EEG-BCI) have been used to detect signs of consciousness in these patients. This approach allows to discover brain responses to command following. Nevertheless, a reliable BCI...

Our objective was to assess the clinical interest of the Nociception Coma Scale Revised (NCS-R) in pain management of patients with disorders of consciousness. Thirty-nine patients with potential painful conditions (e.g., due to fractures, decubitus ulcers or spasticity) were assessed during nursing cares before and after the administration of an a...

Previous studies have shown the prognostic value of stimulation elicited blood-oxygen-level-dependent (BOLD) signal in traumatic patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS). However, to the best of our knowledge, no studies have focused on the relevance of etiology and level of consciousness in patients with disorders of...

Background: Spasticity is a frequent complication after severe brain injury, which may impede the rehabilitation process and diminish the patients' quality of life. Aim: We here investigate the presence of spasticity in a population of non-communicative patients with disorders of consciousness. We also evaluate the correlation between spasticity...

Background Transcranial magnetic stimulation combined with electroencephalography (TMS/EEG) represents a valuable tool to probe cortical excitability and connectivity. Although several procedures have been devised to abolish TMS-related artifacts, direct evidence that it is possible to record TMS-evoked potentials (TEPs) that purely reflect cortica...

Background: Despite recent evidence suggesting that some severely brain-injured patients retain some capacity for top-down processing (covert cognition), the degree of sparing is unknown. Objective: Top-down attentional processing was assessed in patients in minimally conscious (MCS) and vegetative states (VS) using an active event-related poten...

Background: The assessment of pain and nociception in non-communicative patients with disorders of consciousness (DOC) is a real challenge for clinicians. It is, therefore, important to develop sensitive standardized tools usable at the bedside. Objectives: This review aims to provide an overview of the current knowledge about pain processing an...

Background Visual fixation plays a key role in the differentiation between vegetative state/unresponsive wakefulness (VS/UWS) syndrome and minimally conscious state (MCS). However, the use of different stimuli changes the frequency of visual fixation occured in patients, thereby possibly affecting the accuracy of the diagnosis. In order to establis...

Objective: The aim of the study was to validate the use of electromyography (EMG) for detecting responses to command in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (MCS). Methods: Thirty-eight patients were included in the study (23 traumatic, 25 patients >1 year post-onset), 10 diagnos...

Objective: In this study, we investigated the reliability of the Nociception Coma Scale which has recently been developed to assess nociception in non-communicative, severely brain-injured patients. Design: Prospective cross-sequential study. Setting: Semi-intensive care unit and long-term brain injury care. Subjects: Forty-four patients diagnosed...

In spite of medical advances and the increasing number of severely brain-injured patients, the assessment and treatment of patients recovering from coma remain challenging. For over 10 years now, the Coma Science Group has been working on the scientific exploration of disorders of consciousness, with both scientific and clinical research agendas. T...

. Previous findings suggest that language disorders may occur in severely brain-injured patients and could interfere with behavioral assessments of consciousness. However, no study investigated to what extent language impairment could affect patients' behavioral responses. . To estimate the impact of receptive and/or productive language impairments...

Bedside clinical examinations can have high rates of misdiagnosis of unresponsive wakefulness syndrome (vegetative state) or minimally conscious state. The diagnostic and prognostic usefulness of neuroimaging-based approaches has not been established in a clinical setting. We did a validation study of two neuroimaging-based diagnostic methods: PET...

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/unresponsi...