Métastase septique dorsale secondaire d’un abcès rétropharyngé responsable d’une tétraparésie

in Revue Neurologique (2011), 167(8-9), 638-640

Introduction: Peri-tonsillar abscess remains one of the most frequent serous complications of oropharyngeal or dental infections. It can evolve to parapharyngeal and/or retropharyngeal spaces. It can be ... [more ▼]

Introduction: Peri-tonsillar abscess remains one of the most frequent serous complications of oropharyngeal or dental infections. It can evolve to parapharyngeal and/or retropharyngeal spaces. It can be life-threatning and, more rarely, neurological complications are described. Observations: We report the case of a 56 year old woman who developed within few days a progressive tetraparesia due to cervical medullary compression. This compression was consecutive to an epidurite which was a complication of a retropharyngeal abscess. The only surgical act was a cervicotomy to drain the abscess and identify the pathological germ. A targeted antibiotherapy was quickly begun. The recovery was obtained rather quickly and the neurological evolution was good. After one year, the cervical spine presents a post-infectious deformation without sign of root or spinal-cord compression. Conclusion: A cervical tetraparesia induced by spondylodiscitis and epiduritis following a retropharyngeal abscess with Staphylococcus aureus is a rare complication. Adequate diagnosis, as fast as possible, is mandatory in order to carry out an adapted antibiotherapy in the hopes of a complete recovery. The place of surgery on the spine remains to be specified. [less ▲]

Les corrélats neuronaux de l’acquisition et de la consolidation en mémoire dans la maladie d’Alzheimer et le trouble de mémoire isolé

in Revue Neurologique (2009), 165

Introduction : Un déficit en mémoire épisodique est caractéristique dans la maladie d’Alzheimer (AD) et chez les patients âgés présentant une altération cognitive légère (MCI). Cette altération peut ... [more ▼]

Introduction : Un déficit en mémoire épisodique est caractéristique dans la maladie d’Alzheimer (AD) et chez les patients âgés présentant une altération cognitive légère (MCI). Cette altération peut s’expliquer par un déficit d’acquisition et/ou un déficit de consolidation. Toutefois, les modifications cérébrales responsables de ces déficits ne sont pas encore parfaitement élucidées. L’objectif de notre étude était de mettre en relation le profil d’apprentissage déficitaire de ces patients avec leur métabolisme cérébral au repos. Méthode : L’épreuve du California Verbal Learning Test (CVLT) a été administrée à 51 patients AD, 18 patients MCI qui sont restés stables (suivi longitudinal de 18 mois, MCI-S), 16 patients MCI qui ont développé la maladie d’Alzheimer (MCI-C) durant les 18 mois de suivi et 12 participants de contrôle. La mesure d’acquisition est la proportion moyenne de gain à travers les 5 essais d’apprentissage du CVLT. La mesure de consolidation est la proportion totale de pertes à travers ces 5 essais. La mesure du métabolisme cérébral au repos a été effectuée en tomographie par émission de positions (18FDG-TEP). Les mesures de corrélation cognitivo-métabolique ont été réalisées au moyen du logiciel SPM8 (p non-corrigé avec hypothèse a priori <0.001). Résultats : Les groupes AD et MCI-C ont un gain moyen moindre que les groupes MCI-S et contrôles. L’ampleur du gain inter-essais est positivement corrélée à l’activité métabolique au niveau de l’hippocampe postérieur chez les patients AD, à l’activité pariétale inférieure chez les patients MCI-S, et à l’activité frontale postérieure dans le groupe contrôle. Par ailleurs, le groupe AD présente plus de pertes inter-essais que les trois autres groupes. Toutefois, aucune corrélation significative n’apparait entre le total des pertes inter-essais et le métabolisme cérébral. Discussion : Ces données suggèrent que les patients AD, même à un stade très précoce (MCI-C) présentent un déficit d’acquisition de l’information. Ce déficit pourrait être sous-tendu par des perturbations métaboliques dans les réseaux d’apprentissage fronto-pariétaux et hippocampique. Il existe de plus un déficit de consolidation inter-essais spécifique aux patients AD mais ce déficit n’est corrélé à aucune région cérébrale au seuil statistique utilisé. [less ▲]

Le Locked-In Syndrome : la conscience emmurée

in Revue Neurologique (2008), 164

The Locked-In syndrome(LIS) is defined by: (i) the presence of sustained eye opening (bilateral ptosis should be ruled out as a complicating factor);(ii) preserved awareness; (iii) aphonia or hypophonia ... [more ▼]

The Locked-In syndrome(LIS) is defined by: (i) the presence of sustained eye opening (bilateral ptosis should be ruled out as a complicating factor);(ii) preserved awareness; (iii) aphonia or hypophonia; (iv) quadriplegia or quadriparesis; and (v) a primary mode of communication that uses vertical or lateral eye movement or blinking. Acute ventral pontine lesions are its most common cause. Following such brainstem lesions patients may remain comatose for sometime and then gradually awaken, remaining paralyzed and voiceless, superficially resembling the vegetative state. Background. – It has been shown that more than half of the time physicians fail to recognize early signs of awareness in LIS. Given appropriate medical care,life expectancy may be several decades but the chances of good motor recovery remain small. Eye-controlled computer technology now allows LIS patients to communicate and control their environment. Recent studies show that most LIS patients self-report meaningful quality of life and the demand for euthanasia is infrequent. Conclusion. – Patients suffering from LIS should not be denied the right to die – and to die with dignity –but also they should not be denied the right to live–and to live with dignity and the best possible pain and symptom management and revalidation. [less ▲]

EXploration des processus inhibiteurs dans le vieillissement normal et la maladie d'Alzheimer

in Revue Neurologique (2005), 161(12), 467

Memory processing during human sleep as assessed by functional neuroimaging

in Revue Neurologique (2003, November), 159(11 Suppl), 27-29

Sleep is believed to participate in memory consolidation, possibly through off-line processing of recent memory traces. In this paper, we summarize functional neuroimaging data testing this hypothesis ... [more ▼]

Sleep is believed to participate in memory consolidation, possibly through off-line processing of recent memory traces. In this paper, we summarize functional neuroimaging data testing this hypothesis. First, sleep deprivation disrupts the processing of recent memory traces and hampers the changes in functional segregation and connectivity which underpin the gain in performance usually observed in subjects allowed to sleep on the first post-training night. Second, experience-dependent changes in regional brain activity occur during post-training sleep. These changes are shown to be related to the processing of high-level material and to be modulated by the amount of learning achieved during the training session. These changes do not involve isolated brain areas but entire macroscopic cerebral networks. These data suggest a role for sleep in the processing of recent memory traces. [less ▲]

Memory processing during human sleep as assessed by functional neuroimaging.

in Revue Neurologique (2003), 159(11 Suppl), 627-9

Sleep is believed to participate in memory consolidation, possibly through off-line processing of recent memory traces. In this paper, we summarize functional neuroimaging data testing this hypothesis ... [more ▼]

Sleep is believed to participate in memory consolidation, possibly through off-line processing of recent memory traces. In this paper, we summarize functional neuroimaging data testing this hypothesis. First, sleep deprivation disrupts the processing of recent memory traces and hampers the changes in functional segregation and connectivity which underpin the gain in performance usually observed in subjects allowed to sleep on the first post-training night. Second, experience-dependent changes in regional brain activity occur during post-training sleep. These changes are shown to be related to the processing of high-level material and to be modulated by the amount of learning achieved during the training session. These changes do not involve isolated brain areas but entire macroscopic cerebral networks. These data suggest a role for sleep in the processing of recent memory traces. [less ▲]

L'évaluation de la mémoire épisodique

in Revue Neurologique (2002, April 03), 158(Supplément 1), 180

Syndrome du canal lent associe a une translocation autosomique 2q31-9p27.

in Revue Neurologique (2002), 158(5 Pt 1), 605-8

A 27-year-old man complained of cervicoscapular and forearm weakness and amyotrophy. Electromyographic evaluation showed neuromuscular transmission dysfunction and a repetitive compound muscle action ... [more ▼]

A 27-year-old man complained of cervicoscapular and forearm weakness and amyotrophy. Electromyographic evaluation showed neuromuscular transmission dysfunction and a repetitive compound muscle action potential to a single stimulus. Prostigmine did not improve neuromuscular transmission. The genetic analysis of the patient's lymphocytes demonstrated a chromosomic 2q31-9p27 translocation. The combination of the clinical and electrophysiological data as well as the lack of auto-immunity signs against neuromuscular junction constituents led to the diagnosis to congenital postsynaptic myasthenic syndrome also called slow channel syndrome. This congenital myasthenic syndrome is for the first time associated with an autosomal translocation 2q31-9p27. [less ▲]

Exploration neuropsychologique et par imagerie fonctionnelle cérébrale d'une apraxie visuo-imitative

in Revue Neurologique (2000), 156(5), 459-472

We describe the case of a 58-years-old right-handed women suffering from an occipital-parietal lesion. The administration of a cognitively based assessment tool for limb praxis (Batterie d'Evaluation des ... [more ▼]

We describe the case of a 58-years-old right-handed women suffering from an occipital-parietal lesion. The administration of a cognitively based assessment tool for limb praxis (Batterie d'Evaluation des Praxies, B.E.P., Peigneux and Van der Linden, 1998) demonstrated bilateral visuo-imitative apraxia. Gesture production was mainly characterised by spatial, errors, and imitation of meaningful gestures was worse than their pantomime on verbal command. Moreover, the imitation of meaningless gestures and their reproduction on a manikin were worse than imitation of their matched meaningful gestures. In a cognitive perspective, adapted from the Rothi et al. (1997) and Goldenberg (1995) contributions to our understanding of limb praxis, this configuration of performance suggests deficits occurring at multiple levels. On one hand, it suggests either access difficulties or alteration of the output praxicon, i.e., the lexicon for visuo-kinesthetic engrams of meaningful gestures. On the other hand, the simultaneous deficit for meaningless gesture reproduction on the subject's own body and on a manikin favors an alteration of the structural descriptions of the human body (i.e., human body knowledge), underlying the mental transposition processes occurring between the visual analysis of a meaningless gestural configuration and its effective reproduction on oneself or on a manikin, thus contradicting the classic view of a direct pathway linking visual analysis and motor planning in meaningless gesture imitation. Finally, due to the output praxicon deficit, imitation of meaningful gestures is partly processed in the same way as meaningless gestures (also impaired in this case), leading to an interference effect between both degraded memory-based and visually-transposed traces, which account for imitation of meaningful gestures being worse than their pantomime on verbal command. We also assess regional cerebral metabolism using positron emission tomography (PET). Comparison with 41 healthy subjects (SPM96) demonstrated a statistically significant hypometabolism in the left intraparietal sulcus and superior parietal lobule, and in the right dorsal prestriate cortex. These results, together with a review of the other studies of visuo-imitative apraxia, suggest that the left intraparietal sulcus may be associated with access or integration of information from the output praxicon. The left superior parietal and the right dorsal prestriate deficits functionally impaired a bilateral dorsal network implied in the mental transformations of the body, thus suggesting that these mental transformations are underlined by knowledge of the human body, which may subsequently explain the deficit for the reproduction of meaningless and meaningful configurations. [less ▲]

Intérêt d'une procédure de rappel indicé à 48 items dans le diagnostic précoce de la maladie d'Alzheimer

in Revue Neurologique (1999, October 01), 155(Supplément 3), 63-64