Jean-François Albucher

Fluoxetine modulates motor performance and cerebral activation of patients recovering from stroke

In order to determine the influence of a single dose of fluoxetine on the cerebral motor activation of lacunar stroke patients in the early phase of recovery, we conducted a prospective, double‐blind, crossover, placebo‐controlled study on 8 patients with pure motor hemiparesia. Each patient underwent two functional magnetic resonance imaging (fMRI) examinations: one under fluoxetine and one under placebo. The first was performed 2 weeks after stroke onset and the second a week later. During the two fMRI examinations, patients performed an active controlled motor task with the affected hand and a passive one conducted by the examiner with the same hand. Motor performance was evaluated by motor tests under placebo and under fluoxetine immediately before the examinations to investigate the effect of fluoxetine on motor function. Under fluoxetine, during the active motor task, hyperactivation in the ipsilesional primary motor cortex was found. Moreover, fluoxetine significantly improved motor skills of the affected side. We found that a single dose of fluoxetine was enough to modulate cerebral sensory‐motor activation in patients. This redistribution of activation toward the motor cortex output activation was associated with an enhancement of motor performance.

A longitudinal fMRI study: in recovering and then in clinically stable sub-cortical stroke patients

The aim of this 1-year longitudinal fMRI study was to compare hand motor activation patterns between cerebrovascular paretic patients with a subcortical infarction and healthy elderly subjects and to evaluate the changes between the subacute phase and the chronic phase of recovery. We studied eight right-handed patients with pure motor hemiparesis due to a single ischemic infarct of the corticospinal tract. Each patient underwent a first fMRI (E1) 20 +/- 9 days after stroke, a second (E2) after 4 months and a third (E3) 12 months after stroke. During each fMRI session, the patients performed an active motor task consisting of audio-paced (1 Hz) finger flexion-extension of the paretic hand and underwent a passive motor task consisting of flexion-extension of the paretic hand performed by an examiner. Data were analyzed with SPM99 (random effect analyses). Patients had recovered at E2, were stable between E2 and E3, but still experienced a hand weakness. Displacement of activation maxima coordinates in patients compared to healthy subjects suggested an early reorganization within the SMA and a secondary reorganization within the ipsilesional S1M1 at E2. The main differences between patients and healthy subjects were (1) recruitment of the posterior part of the cingulate cortex and SMA, (2) a general hyperactivation (except in the deefferented primary motor cortex) and (3) an evolution in the S1M1 activation from an early (20 days after stroke) contralesional hyperactivation to a later (4 months after stroke) ipsilesional hyperactivation concomitant to recovery. Changes in activation were confirmed by the passive task that involved no effort and little attention. Despite clinical stability, changes in brain processing seemed to occur between E2 and E3 corresponding to a normalization of ipsilesional S1M1 activation, a decrease of bilateral cerebellar activation, and a progressive increase in SII-BA 40 activity suggesting evolving compensatory networks to sustain recovery.

Correlation between cerebral reorganization and motor recovery after subcortical infarcts.

Our objective was to investigate correlations between clinical motor scores and cerebral sensorimotor activation to demonstrate that this reorganization is the neural substratum of motor recovery. Correlation analyses identified reorganization processes shared by all patients. Nine patients with first-time corticospinal tract lacuna were clinically evaluated using the NIH stroke scale, the motricity index, and the Barthel index. Patients were strictly selected for pure motor deficits. They underwent a first fMRI session (E1) 11 days after stroke, and then a second (E2) 4 weeks later. The task used was a calibrated repetitive passive flexion/extension of the paretic wrist. The control task was rest. Six healthy subjects followed the same protocol. Patients were also clinically evaluated 4 and 12 months after stroke. All patients improved significantly between E1 and E2. For E1 and E2, the ipsilesional primary sensorimotor and premotor cortex, supplementary motor area (SMA), and bilateral Broadmann area (BA) 40 were activated. Activation intensity was greater at the second examination except in the ipsilesional superior BA 40. Magnitude of activation was lower than that of controls except for well-recovered patients. E1 clinical hand motor score and E1 cerebral activation correlated in the SMA proper and inferior ipsilesional BA 40. Thus, we demonstrated early functionality of the sensorimotor system. The whole sensorimotor network activation correlated with motor status at E2, indicating a recovery of its function when activated. Moreover, the activation pattern in the acute phase (E1) had a predictive value: early recruitment and high activation of the SMA and inferior BA 40 were correlated with a faster or better motor recovery. On the contrary, activation of the contralesional hemisphere (prefrontal cortex and BA 39-40) and of the posterior cingulate/precuneus (BA 7-31) predicted a slower recovery.

Anodal tDCS Combined With Radial Nerve Stimulation Promotes Hand Motor Recovery in the Acute Phase After Ischemic Stroke

Background and Objective. The question of the best therapeutic window in which noninvasive brain stimulation (NIBS) could potentiate the plastic changes for motor recovery after a stroke is still unresolved. Most of the previous NIBS studies included patients in the chronic phase of recovery and very few in the subacute or acute phase. We investigated the effect of transcranial direct current stimulation (tDCS) combined with repetitive peripheral nerve stimulation (rPNS) on the time course of motor recovery in the acute phase after a stroke. Methods. Twenty patients enrolled within the first few days after a stroke were randomized in 2 parallel groups: one receiving 5 consecutive daily sessions of anodal tDCS over the ipsilesional motor cortex in association with rPNS and the other receiving the same rPNS combined with sham tDCS. Motor performance (primary endpoint: Jebsen and Taylor Hand Function Test [JHFT]) and transcranial magnetic stimulation cortical excitability measures were obtained at baseline (D1), at the end of the treatment (D5), and at 2 and 4 weeks’ follow-up (D15 and D30). Results. The time course of motor recovery of the 2 groups of patients was different and positively influenced by the intervention (Group × Time interaction P = .01). The amount of improvement on the JHFT was greater at D15 and D30 in the anodal tDCS group than in the sham group. Conclusion. These results show that early cortical neuromodulation with anodal tDCS combined with rPNS can promote motor hand recovery and that the benefit is still present 1 month after the stroke.

Fou Rire Prodromique Heralding a Left Internal Carotid Artery Occlusion

BACKGROUND Four rire prodromique, described as pathological laughter preceding the onset of an apoplectic attack, is a rare phenomenon. CASE DESCRIPTION A 61-year-old man manifested pathological laughter before a sudden right hemiplegia. MRI showed a left lenticular and caudate nucleus infarct with involvement of the external capsule and prerolandic area. MRA revealed a left internal carotid and middle cerebral artery occlusion. CONCLUSIONS The clinicoanatomic correlates of this phenomenon are discussed.

Évaluation à 4 ans de la filière « Urgences AVC » de l’Hôpital Purpan (Toulouse) et analyse de 69 patients consécutifs traités par rt-PA intra-veineux

Resume Introduction L’obtention en 2002 de l’AMM europeenne pour l’utilisation du rt-PA dans la fibrinolyse des AVC ischemiques Methodes Nous rapportons la mise en place et l’activite depuis 2002 de la filiere « Urgences AVC » de l’hopital Purpan (Toulouse). Resultats 10,2 p. 100 des AVC de tous types (ischemiques et hemorragiques) hospitalises dans le service de Neurologie ont ete pris en charge par la filiere dans l’optique d’un traitement fibrinolytique. Parmi eux, 25,6 p. 100 ont ete traites par rt-PA (2,6 p. 100 des AVC de tous types) avec un score moyen de NIHSS a l’admission de 15,8 [5 ; 25]. L’imagerie utilisee pour selectionner les candidats a la thrombolyse etait le scanner dans 90 p. 100 des cas. Le delai moyen de traitement etait de 2 h 25 et celui intra-hospitalier de 40 minutes. Deux patients (3 p. 100) ont presente une hemorragie intra-cerebrale symptomatique. Le taux de deces etait de 18,8 p. 100. A 3 mois, 53,5 p. 100 des patients etaient « independants » (Rankin Conclusion Ces resultats confirment la faisabilite, la reproductibilite, l’efficacite et la surete du traitement thrombolytique par rt-PA dans les AVC ischemiques inferieurs a 3 heures dans notre centre. La mise en place d’une filiere « Urgences AVC » est un outil necessaire pour traiter le plus grand nombre de patients dans les meilleurs delais.

Embolie gazeuse cérébrale iatrogène d’origine veineuse sans signe respiratoire : un mécanisme rétrograde ?

INTRODUCTION Air embolism is a rare complication of various invasive medical procedures. Venous cerebral air embolism is usually the consequence of paradoxical embolism. We report a case of isolated cerebral air embolism resulting from a non-paradoxical mechanism. CASE REPORT A few minutes after his central venous catheter had been accidentally disconnected, a 63-year-old man developed left-sided rhythmic jerking movements followed by left hemiplegia. There were no associated cardiologic or pulmonary signs. Brain CT showed air bubbles in the right frontal cortical sulci. The brain MRI DWI and FLAIR sequences showed a high intensity right frontal cortical lesion without reduction in ADC. Transesophageal echocardiogram did not find a patent foramen ovale. CONCLUSIONS In this case of venous cerebral air embolism, the lack of any cardiopulmonary manifestation, the lack of a patent foramen ovale and the neuroradiological findings are not in favor of the hypothesis of paradoxical embolism. The hypothesis of retrograde venous cerebral air embolism is discussed.

O3-6 Evaluation du fonctionnement cognitif et psycho comportemental après un premier infarctus cérébral symptomatique

Introduction Le but de ce travail a ete de preciser le profil et la severite du deficit neuropsychologique (cognitif et comportemental) a 3 mois d’un premier infarctus cerebral symptomatique chez des patients ayant retrouve une autonomie fonctionnelle satisfaisante. Methode Cette etude a ete proposee a 60 patients consecutifs, âges de 18 a 80 ans, hospitalises dans le service de Neurologie vasculaire pour un premier infarctus cerebral prouve et ne presentant pas d’alteration cognitive avant l’episode vasculaire (IQ-Code). Une evaluation clinique (neuropsychologique et somatique) a ete realisee trois mois apres l’infarctus cerebral. N’ont ete inclus dans cette etude que les patients ne presentant pas d’aphasie, d’apraxie, d’heminegligence severes et ayant retrouve une autonomie fonctionnelle motrice satisfaisante (Rankin Resultats Les patients sont significativement plus alteres sur l’ensemble des domaines cognitifs, en particulier sur les fonctions executives avec une plus grande perturbation des fonctions d’initiation, d’inhibition et de flexibilite mentale. De maniere similaire, les patients etaient plus apathiques que les sujets controles mais aucune difference n’a ete retrouvee sur le score de depression. Aucune correlation n’a ete retrouvee entre alteration et plainte cognitive. De plus il a ete retrouve une correlation forte entre les donnees d’imagerie a la phase aigue (diffusion et T2) et les performances cognitives a 3 mois mais egalement une correlation entre plusieurs parametres de la prise en charge initiale et le statut cognitif a 3 mois. Conclusion Dans cette population specifique de patients ayant retrouve une autonomie fonctionnelle a 3 mois de l’episode aigu, 33% presentent une alteration cognitive et psycho-comportementale caracterisee et repondent aux criteres du Vascular Cognitive Impairment No Dementia (VCI-ND). Un suivi a 1 an est en cours tant pour suivre l’evolution des patients symptomatiques que pour detecter une alteration chez les patients asymptomatiques.