Cognitive Impact of Benzodiazepin Withdrawn After Curative Epilepsy Surgery in Children With Focal Epilepsy

1. Research Assumptions Epilepsy is a frequent group of diseases, affecting 1% of the general population with a higher incidence in children. Anti-epileptic drugs are used as the main treatment. The choice of an anti-epileptic treatment is based on the benefit-risk balance. The purpose of the treatment should not only be efficacy, the presence of side effects is a major factor to be taken into account. Thus, in children with resistant epilepsy (20 to 30% of epilepsy), the objective is not necessarily to be seizure free but to achieve the lowest possible frequency of seizures with the lowest possible side effects.

When assessing the benefit-risk ratio of antiepileptic treatment, it is important to keep in mind that the child has a developing brain whose main activity is learning. Special attention should be paid to minimize treatment related cognitive consequences. Be particularly wary of combination therapies (combinations of several antiepileptic treatments). Indeed, it is well established that they are more harmful than monotherapy. It is also important to avoid the use of drugs with too strong cognitive effect of their own. Some molecules such as phenobarbital or topiramate have been the subject of a few studies that have established their deleterious effect on the cognitive level. Benzodiazepines are available drug used as antiepileptic drugs. In France, clobazam and clonazepam have a Marketing Authorization for children.

Although effective in children with epilepsy, benzodiazepines seem to raised a significant number of problems. One of them is the absence of study determining whether these molecules have cognitive consequences. In order to have more data to better establish the risk-benefit balance of benzodiazepines in the treatment of children with epilepsy, the investigators wish to conduct work to evaluate the cognitive consequences of benzodiazepines in children treated for epilepsy.

Hypothesis tested: Benzodiazepines have cognitive consequences in children treated for epilepsy The investigators will conduct a prospective study on the cognitive impact of benzodiazepine withdrawal after successful curative epilepsy surgery in children. The investigators will focus, through neuropsychological tests, on the working memory and attention abilities of children with drug-resistant epilepsy who require surgery and are receiving a benzodiazepine. The three assessments (pre-surgical (seizures and benzodiazepine); post-surgical (no seizure and benzodiazepine) and post benzodiazepine discontinuation (no seizure and benzodiazepine)) will assess the impact of benzodiazepines on working memory and attention abilities.

The data from this study will allow physicians to better understand the balance of benefit and risk balance of benzodiazepine use in children with epilepsy. These data could lead to the writing of a good use for the treatment of epilepsy in children and avoid misuse if the cognitive impact is significant. 2. Description of the studied population and justification for its choice Children followed for drug-resistant epilepsy in preoperative assessment will be selected by the coordinator's team or one of the partners. Indeed, only this methodology (pre- and post-operative comparison with and without benzodiazepine) will make it possible to answer the question asked and in particular the comparison of post-operative evaluation with benzodiazepines with post-operative evaluation after stopping benzodiazepines 3. Benzodiazepin as antiepileptic drugs Efficiency profile: The efficacy spectrum of clobazam and clonazepam is quite broad since these molecules have shown their efficacy in controlled trials on absences, myoclonias, atonic seizures and focal seizures as well as in open trials on generalized tonic-clonic and focal seizures. Some authors have even suggested that clonazepam may be the third line treatment in Lennox-Gastaut syndrome.