Abstracts

Rationale: As a palliative epilepsy surgery, callosotomy is mainly indicated in those patients with drop attacks and bilateral synchronous EEG discharges. However, as a less invasive procedure, vagus nerve stimulation (VNS) dramatically decreased its choice. Although in the absence of controlled studies comparing the two procedures, there is evidence for a more effective seizure outcome after callosotomy as compared with VNS (Nei M at al., Epilepsia 2006; 47:115-122; Cukiert A et al., Epilepsia 2009; 50:1377-1380). We aim to show callosotomy keep being a rational first strategy whenever properly indicated. Methods: Retrospective, observational study of patients submitted to callosotomy in two hospitals, after pre-surgical evaluation in the scope of the respective epilepsy surgery groups. Seizures outcome assessment by using the follow scale: decreased > 75%, 50 - 75%, 25 - 50%, < 25%. Post- surgery quality of live assessment by asking relatives whether surgery has been worse while or not. Comparison of the results with those of the VNS related literature. Results: Twenty one patients, 17 males; epilepsy aetiology: Lennox-Gastaut syndrome (8), peri or postnatal injury (5), cortical development malformation (3), other or no identified causes (5); median age of surgery of 21.1 years; median time from epilepsy onset to surgery of 17.3 years; most frequent seizure types: atonics/ myoclonics (dropp- attacks- 22), atypical absences/ (10), tonics (7), focal (6), tonic-clonics (TC- 4); interictal EEG: multifocal (13), bilateral (13) and focal (3); extension of callosotomy: total in 12 and anterior 2/3 in 9; surgery morbidity: transient disconnection syndrome (4), hydrocephalus (1), CSF fistula (1), transient focal deficits (3); post-surgery men time of follow-up: 4.0 years; decreased seizures (n=19): >