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Laurent Vercueil

Publications and source records attributed to Laurent Vercueil.

8 recordsLinked to original sources
PubMed2002

Superior colliculus firing changes after lesion or electrical stimulation of the subthalamic nucleus in the rat.

Recent data have suggested a critical role for the basal ganglia in the remote control of epileptic seizures. In particular, it has been shown that inhibition of either substantia nigra pars reticulata or subthalamic nucleus as well as activation of the superior colliculus suppresses generalized seizures in several animal models. It was previously shown that high frequency stimulation of the subthalamic nucleus, thought to act as functional inhibition, stopped ongoing non-convulsive generalized seizures in rats. In order to determine whether high frequency stimulation of the subthalamic nucleus involved an activation of superior colliculus neurons, we examined the effects of subthalamic nucleus manipulation, by either high frequency stimulation or chemical lesion, on the spontaneous electrical activity of superior colliculus neurons. Acute high frequency stimulation of the subthalamic nucleus (frequency 130 Hz) induced an immediate increase of unitary activity in 70% of responding cells, mainly located within the deep layers, whereas a reduction was observed in the remaining 30%. The latter responses are dependent on the intensity and frequency of the stimulation. Unilateral excitotoxic lesion of the subthalamic nucleus induced a delayed and transient decrease of superior colliculus activity. Our data suggest that high frequency stimulation of the subthalamic nucleus suppresses generalised epileptic seizures through superior colliculus activation.

Action Potentials↗
PubMed2002

Results of deep brain stimulation for dystonia: a critical reappraisal.

Deep brain stimulation for severe dystonia is still in the very first stage of development. Only single case reports or small case series have been reported to date. Best results have been obtained with pallidal stimulation in patients with primary generalised dystonia, especially in DYT1 mutation carriers. In secondary dystonia, conflicting results were reported. However, there is today enough promising evidence for a striking efficacy of pallidal stimulation in dystonia, supporting the need for further investigations in the field, with collaborative projects (regarding to the limited number of eligible patients); double-blind studies, including a consensus about surgical method; and a precise anatomic analysis of the position of the electrode. A careful assessment of the efficacy by using improved clinical scale is also warranted.

Dystonia↗
PubMed2002

Co-occurrence of infantile epileptic seizures and childhood paroxysmal choreoathetosis in one family: clinical, EEG, and SPECT characterization of episodic events.

The co-occurrence of infantile convulsions and childhood paroxysmal choreoathetosis (ICCA syndrome) has recently been reported in several families. The pattern of familial clustering observed is consistent with a single locus mutation which has been mapped onto the pericentromeric region of chromosome 16. We studied the main clinical, electroencephalogram (EEG), and single photon emission computed tomography (SPECT) characteristics of episodic events in a new family presenting clinical features similar to that described in the ICCA syndrome. In the first year of life, a mother and her two daughters suffered from rare afebrile seizures lasting from 30 seconds to 15 minutes. Ictal EEG recording in one daughter at 7 months of age showed bilateral polyspikes with a posterior predominance. In the three patients, epileptic seizures regressed within a few weeks, and never reoccurred. At the age of 7 and 12 years, respectively, the two daughters presented daily brief (20 seconds to 1 minute) involuntary choreoathetotic episodes. In 10 of these attacks, EEG did not show any epileptiform abnormalities. In both sisters, an ictal SPECT was performed during a choreoathetotic episode. Subtracting the ictal SPECT from the interictal SPECT coregistered to magnetic resonance imaging (MRI) revealed significant modifications in the local cerebral perfusion in the sensorimotor cortex, the supplementary motor areas, and pallidum. Carbamazepine completely suppressed paroxysmal dyskinesias. These observations, together with literature data, suggest that in this syndrome, depending on brain maturation, the same genetic abnormality may result in different paroxysmal neurological symptoms.

Athetosis↗
PubMed2002

Seizures and the basal ganglia: a review of the clinical data.

This article attempts an overview of the clinical and electrophysiological evidence supporting the involvement of the basal ganglia in epileptic seizures. In contrast to animal data, evidence for a role of these structures in human epilepsies is lacking. However, from the theoretical point of view, it remains conceivable that, given their strong interconnectivity, basal ganglia could be functionally linked to the cerebral cortex during an epileptic seizure. Several clinical ictal aspects have been suggested to be compatible with the involvement of basal ganglia, namely, ictal dystonic posturing during temporal lobe seizures, rotatory seizures and paroxysmal dyskinesia-like seizures. On the other hand, basal ganglia dysfunction may also influence some aspects of epilepsy, as suggested by pure basal ganglia pathology such as Parkinson's disease, or the described effect of an acute basal ganglia lesion in epileptic patients. The data discussed in this review may stimulate further research to link basic scientific data to human epilepsies, and lead to the development of novel therapeutical solutions.

Animals↗
PubMed2000

Parkinsonism and Epilepsy: Case Report and Reappraisal of an Old Question.

Since Yakovlev's contribution in 1928, very few cases with parkinsonism and epilepsy have been reported in the literature. While antagonism has been claimed between the two conditions, little is hypothesized about the pathophysiological mechanisms involved. We report the case of a patient with both temporal lobe epilepsy and Parkinson's disease, who presented with a dramatic decrease in seizure frequency when the parkinsonian signs developed and disappearance of motor fluctuations following recurrence of seizures. On the basis of recent knowledge regarding both pathologies we propose new insights into this old question.

Journal Article↗