Abstracts

RATIONALE: To compare the efficacy of the section of different anatomical segments of the CC in the control of refractory DA.There is still fresh debate about the validity of CCSx for the alleviation of malignant (DA).It is still unclear which anatomical segment(s)of the CC need to be sectioned in order to provide the best possible results. METHODS: We statiscally compared the percent reduction of DA following anatomically variable partial or complete CCSx in 23 patients with symptomatic generalized or multifocal epilepsies, followed for at least one year after the last procedure. RESULTS: There were 3 major findings:(i) irrespective of the anatomical extent of the CCSx,there was a significant reduction in the occurrence of DA after the procedure (p=0.013);(ii)patients with selective posterior CCSx had a greater reduction in the occurrence of DA than patients in whom more posterior portions where spared(either selective anterior or "two-thirds"CCSx) (p=0.07,and 0.02, respectively);(iii)there was no statistically significant difference between the results obtained with total versus selective posterior CCSx(p=0.18). CONCLUSIONS: These findings strongly suggest that the fibers decussating in the posterior segments of the CC are pivotal for secondary bilateral synchronization of epileptic activity leading to DA. Thus, contrary to the traditional approach, selective posterior CCSx should perhaps be the first procedure to be perfomed in patients with drop attacks.