Risk factors for developing epilepsy after craniotomy in children

Introduction We performed a retrospective analysis of children undergoing supratentorial craniotomy, attempting to identify possible risk factors for postoperative epilepsy and the need for prophylactic anticonvulsant therapy.Materials and methods We analysed 107 consecutive patients (55% males) who had supratentorial craniotomy for a variety of diagnoses (tumours, trauma, infection, vascular malformations and others) during 1995–1999. Mean age at operation was 89 months (range: 1–180 months). Patients who presented with epilepsy were excluded. Postoperative epilepsy was considered present if patients required systematic pharmacological treatment, at a minimum follow-up of 6 months. Linear regression was used to analyse the effect of sex, anticonvulsant prophylaxis, duration of operation, closure of dura, postoperative infection, the diagnosis, anatomical region of brain affected, operation type (craniotomy/craniectomy) and the need for brain resection.Results Prophylactic anticonvulsants were given to 52% of the patients; 97% had craniotomy; in five patients, the dura was left open; in 33%, some kind of brain tissue resection had been performed; two patients (1.8%) developed postoperative infection; one patient died. Only 13 patients (12%) developed postoperative epilepsy. The only two factors with statistical significance were female sex (p=0.045) and the absence of dural closure (p=0.001). All other factors were not significant (p>0.258).Conclusions Postoperative epilepsy after supratentorial craniotomy is uncommon in children, incidence being 12%. The administration of prophylactic anticonvulsants does not appear to influence the risk of epilepsy. Surprisingly, females have statistically higher risk. Lack of dural closure has higher risk of epilepsy, but this may reflect the type of pathology.The material of this paper was presented at the 18th Biannual Congress of the European Society for Pediatric Neurosurgery, Kiruna, 15 June 2002.