[Surgical treatment for epilepsy in children: indications and complications]

Abstract

The main etiologies of epilepsy are somewhat different in the pediatric population, from those found in the adults. This explains why temporal resections are less frequently performed in children than in adults. To be considered for resective (curative) surgery, most seizures have to been proved to arise exclusively from one area of the brain that is functionally silent. The drug-resistance must be certain, and the patient, or his family, must be strongly motivated to undergo surgery. Hemispherotomy, which consists in complete disconnection of one hemisphere, is a curative technique, which may be considered where there is a pre-existing hemiplegia associated with a structural abnormality of the contralateral hemisphere. Callosotomy is a palliative technique, which consists in disconnecting the hemispheres, one from the other. It may be considered in individuals having frequent atonic seizures (drop attacks). Multiple subpial transection involves transection of transverse fibers, leaving longitudinal fibers intact. It may be performed if the epileptogenic focus is located in an eloquent brain area. It may also be performed in case of Landau-Kleffner syndrome. The complication rate of resective surgery is low. Contralateral motor impairement is the main permanent complication related to cortical resection. It is a rare occurrence (1 to 2 percent of cases) due to peroperative lesions of the sylvian vasculature, or of the anterior choroidal artery, or even of the motor area. Postoperative hematomas, infections, or hydrocephalus may also occur in 2 to 6 percent of cases, depending on the authors. Some postoperative neuropsychological complications are reported in the literature, especially after surgery on the dominant side. Hydrocephalus and infection are the most frequent complications occurring after hemispherotomy (10 percent of cases). Dysconnexion syndrome is a rare complication, which can be seen after total callosotomy. It is unusual for the effects of disconnection after anterior callosotomy to represent significant handicap. Permanent postoperative worsening of a pre-existing neurological impairement is seen in less than 10 percent of the cases after multiple subpial transection. In conclusion, surgery has to be considered without unnecessary delay in the children presenting with drug-resistant epilepsy, before any cognitive or psychosocial deterioration, due to the epileptic disease, occurs.