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Jacques Luauté

Publications and source records attributed to Jacques Luauté.

8 recordsLinked to original sources
PubMed2006

Visuo-spatial neglect: a systematic review of current interventions and their effectiveness.

Left visuo-spatial neglect is a well-recognized predictor of poor functional outcome following right hemisphere stroke. Over the past 60 years, 18 different methods have been described and evaluated aimed at reducing the effects of this impairment. Although there are some grounds for optimism particularly in terms of short-term impairment-based effects, the range and degree of disability borne by many patients remain high and the clinical effectiveness of the different methods viewed in terms of long-lasting functional improvement (i.e. improvement of disabilities or handicap) is not clear. A systematic review of the available clinically relevant literature, using comparative and stringent levels of evidence, indicates that visual scanning training (VST), trunk rotation (TR) or repeated neck muscle vibrations (NMV) when associated with an extensive training program, mental imagery training, video feedback training and prism adaptation (PA) can be recommended for the rehabilitation of patients with left neglect. More studies however are needed to determine the optimal paradigm of limb activation (LA) eliciting a sustained functional improvement. Sensory stimulations alone and Fresnel prisms do not appear to be functionally relevant. For the other methods, the actual literature is not sufficient to conclude whether or not a long-term functional improvement can be achieved.

Functional Laterality↗
PubMed2006

Improved prediction of awakening or nonawakening from severe anoxic coma using tree-based classification analysis.

OBJECTIVE: To evaluate the utility of sensory and event-related evoked potentials for the prediction of awakening/nonawakening in severe anoxic coma and to design a decision tree helping decision for any patient in this condition. DESIGN: Prospective cohort study. SETTING: Clinical neurophysiology unit and intensive care unit of a French university hospital. PATIENTS: Sixty-two consecutive severe comatose patients after out-of-hospital cardiac arrest. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We gathered clinical variables and recorded the somatosensory, auditory, and cognitive evoked potentials within an average period of 8 days after cardiac arrest. The patients were followed for 12 months and classified as awake or nonawake (permanent vegetative state or death). The statistical study included measurements of specificity, sensitivity, and positive and negative predictive value for each clinical and electrophysiologic variable recorded at the early stage of coma. Furthermore, a tree-based classification analysis was performed.All patients in whom somatosensory evoked potentials or middle-latency auditory evoked potentials were abolished did not awaken (100% specificity). All patients in whom mismatch negativity (MMN) was present awakened (100% specificity). MMN was superior to somatosensory evoked potentials for the prediction of awakening and had the best specificity and positive predictive value for awakening. On the decision tree, the awakening/nonawakening explicative variables were, by order of importance, MMN, pupillary reactivity, and somatosensory evoked potentials. CONCLUSIONS: There is a need to predict early and accurately awakening or nonawakening in postanoxic comas. Using sensory and cognitive evoked potentials to assess the functional condition of the brain, a prognostic tree for the prediction of awakening/nonawakening in severe anoxic coma has been designed. It is applicable to any patient in this condition and offers the possibility to predict with very high probability awakening when MMN, the earliest component of event-related potentials, is present and nonawakening when MMN and pupillary light reflex are absent or cortical components of somatosensory evoked potentials are abolished.

Adolescent↗
PubMed2006

Prism adaptation first among equals in alleviating left neglect: a review.

PURPOSE: The current paper was designed to provide a critical overview on the different methods proposed for the rehabilitation of left spatial neglect. METHODS: On the basis of a previous systematic review of the literature, we analyzed all articles available aiming at reducing left spatial neglect which included a long term functional assessment. RESULTS: The aim of most early rehabilitation approaches, such as visuo-scanning training, was to re-orient visual scanning toward the neglected side. This review confirmed the utility of this method for rehabilitation purposes. More recent - theory driven - procedures, also based on a training approach, include limb activation, mental imagery training and video-feedback training. Although there is ground for optimism, the functional effectiveness of these methods still relies on few single-case studies. Newer methods have tried to stimulate automatic orientation of gaze or attention towards neglected space in a bottom-up fashion. Sensory stimulations can remove most of the classical signs of left neglect but their effects are short-lived. Such stimulations are not functionally relevant for rehabilitation except for trunk rotation or repeated neck muscle vibrations if they are associated with an extensive training program. A more promising intervention is prism adaptation given the growing evidence of relatively long-term functional gains from comparatively short term usage. CONCLUSION: Overall, there is now evidence for several clinically relevant long-term benefits in the case of visual scanning training, mental imagery training, video feedback training, neck muscle vibration and trunk rotation if associated with visual scanning training and prism adaptation. However, the amount of evidence is still limited to a small number of relevant published articles and it is mandatory to continue the research in this field. In this review, the possible routes for new rehabilitation procedures are discussed on the basis of the actual knowledge regarding the neuro-cognitive mechanisms underlying the therapeutic effect of prism adaptation.

Adaptation, Physiological↗
PubMed2005

Late auditory and event-related potentials can be useful to predict good functional outcome after coma.

OBJECTIVE: To investigate whether late auditory and event-related potentials, and in particular N100 and mismatch negativity, together with clinical parameters, can help to predict good functional outcome in comatose patients. DESIGN: Prospective cohort study. SETTING: Hospital. PARTICIPANTS: Consecutively sampled comatose patients (N=346) whose etiologies of coma were stroke (125 patients), brain injury (96 patients), anoxia (64 patients), complication of neurosurgery (54 patients), and encephalitis (7 patients). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Glasgow Outcome Scale score at 1 year postonset. Patients in a minimally conscious state and those who awoke and died during the follow-up period were classified separately. RESULTS: Univariate analysis showed that all variables studied, except brainstem auditory evoked potentials, correlated significantly with functional outcome. Mismatch negativity showed the highest positive predictive value for good outcome. A validated model was obtained with multivariate logistic analysis, including pupillary light reflex, N100, mismatch negativity, etiology, and age. CONCLUSIONS: Late auditory and event-related potentials, and particularly N100 and mismatch negativity, provide strong prognostic factors for good functional outcome. Furthermore, these components may enhance the accuracy of prognosis when associated with other clinical parameters available at the early stage of coma.

Adolescent↗
PubMed2004

Predictive value of sensory and cognitive evoked potentials for awakening from coma.

OBJECTIVES: To determine the prognostic role of late auditory (N100) and cognitive evoked potentials (MMN) for awakening in a cohort of comatose patients categorized by etiology. METHODS: The authors prospectively studied a series of 346 comatose patients. Coma was caused by stroke (n = 125), trauma (n = 96), anoxia (n = 64), complications of neurosurgery (n = 54), and encephalitis (n = 7). Patients were followed for 12 months and classified as awake or unawake. Univariate and multivariate analyses were performed using regression logistic and Cox models. RESULTS: Pupillary light reflex, N100, middle-latency auditory evoked potentials, age, and etiology were the most discriminating factors for awakening. Statistical analysis showed that pupillary reflex was the strongest prognostic variable for awakening (estimated probability 79.7%). The estimated probability of awakening rose to 87% when N100 was present and to 89.9% when middle-latency evoked potentials (MLAEPs) were present. It was 13.7% when pupillary reflex was absent in anoxic patients. When MMN was present, 88.6% of patients awakened. No patient in whom MMN was present became permanently vegetative. CONCLUSION: Pupillary reflex is the strongest prognostic variable, followed by N100 and MLAEPs allowing a reliable model for awakening. The presence of MMN is a predictor of awakening and precludes comatose patients from moving to a permanent vegetative state. Evaluation of primary sensory cortex and higher-order processes by middle-latency-, late, and cognitive evoked potentials should be performed in the prognosis for awakening in comatose patients.

Adolescent↗
PubMed2003

Simulating unilateral neglect in normals using prism adaptation: implications for theory.

Rightward deviation on line bisection is considered one of the most classic clinical signs of unilateral visual neglect--a cognitive disorder of spatial processing that commonly follows right brain damage. Recently, short-term adaptation to wedge prisms has been shown to significantly reduce neglect on this and other conventional diagnostic tasks. Our previous study has shown that visuomotor adaptation in normals produces a similar pattern of directional bias on a line bisection task. Based on the good working knowledge of how neglect patients perform on different versions of the standard diagnostic task, we showed here that using leftward-deviating prisms in normals, it is possible to produce: (1) a reliable bias on line bisection, (2) a rightward specific deviation, (3) a modulation of rightward deviation, which depends on the relative spatial location of the target lines and (4) a line length effect. A final experiment confirmed that these after-effects are specific to prism adaptation rather than passive prism exposure. Collectively, these findings confirm that adaptation to left-deviating prisms in normals produces a reliable right-sided bias and as shown by a previous visuospatial judgement task, these findings cannot be adequately explained by the symmetric sensori-motor effects of prism adaptation. Taken together with the improvement of spatial neglect shown by right-deviating prisms only, the present study suggests that low level sensori-motor adaptations play a greater role in right hemisphere organisation for spatial cognition than previously thought.

Adaptation, Physiological↗
PubMedDate not supplied

Evoked potentials for the prediction of vegetative state in the acute stage of coma.

For comatose patients in intensive care units, it is important to anticipate their functional outcome as soon and as reliably as possible. Among clinical variables the Glasgow Coma Score (GCS) and the patient's pupil reactivity are the strongest predictive variables. Evoked potentials help to assess objectively brain function. Over the past 20 years, numerous studies have assessed their prognostic utility in terms of awakening from coma. Fewer studies, however, have focused upon the utility of evoked potentials in predicting progression to the vegetative state. In this area evoked potentials appear to have a highly predictive value. In anoxic coma the abolition of somatosensory evoked potentials (SEPs) is related to a poor outcome, defined as death or survival in a vegetative state, with a 100% specificity. Following traumatic brain injury, the predictive value for unfavourable outcome is 98.5% when there are no focal injuries likely to abolish SEP cortical components. In contrast, the presence of event-related evoked potentials, and particularly mismatched negativity (MMN), is a strong predictor of awakening and precludes comatose patients from moving to a permanent vegetative state (PVS).

Acute Disease↗