Abstracts

Rationale: Focal Cortical Dysplasias (FCD) are now recognized as one of the most important epileptogenic causes for refractory focal epilepsy. FCD type II is a highly epileptogenic lesion frequently associated with early onset drug-resistant partial epilepsy according to the classification outlined by International League Against Epilepsy (ILAE) and on the criteria of Palmini-Blumcke.Focal cortical dysplasia is a potentially surgically remediable syndrome for patients with associated intractable seizures, although reported outcomes concerning postoperative seizure control have been mixed. In the study by Engel and colleagues 65% of patients with anteromesial temporal resections were seizure free, while 21% and 14% did not improve, in contrast Siew-Ju See and colleagues reported a 42% seizure freedom in patients that went under epilepsy surgery in 2013.Evaluation of postsurgical seizure outcome and other features such as the histopathological characteristic of FCD population according to previously introduced classification systems have been widely discussed in the literature, however only a few studies that focused on the use of ILAE classification has been published in the current literature and none has studied Latino population, which is the aim of our research. Methods: Patient cohort retrospectively studied in this study consists of both pediatric and adult patients with histopathologically proven FCD only, who underwent surgical treatment for the drug-resistant epilepsy at The National Institute of neurology and neurosurgery ”Manuel Velasco Suarez”. Only those with FCD type II were included, with a total of 101 patients.in addition to that, we divided the patients in two groups, those with FCD type IIa and those with FCD type IIb. We compared the location of the lesions between the patients, it’s clinical characteristics and their surgery outcome, the latter according to Engel’s classification.Data analyses were performed using the IBM SPSS 22 software statistical package. The significance level was set at 5% (p < 0.05). Categorical analysis was performed using chi-square test for qualitative data with Bonferroni corrections. Other quantitative comparisons were done using Wilcoxon test,Mann- Whitney U test, OR Kruskal- Wallis test . To analize the freedom of crisis Kaplan Meir was applied. Results: 56% of drug-resistant partial epilepsy were male, while 44% were female, of our total of 101 patients 59 showed FCD type IIa while 42 patiets were classified as FCD type IIb, here was not an association between the cortical dysplasia and the surgery outcome with an r of -0.071 and P =0.485  Kaplan Meir curves showed a sudden fall 2 years after the surgery.   Conclusions: To our knowledge, this study is the first to investigate postoperative outcome between the ILAE focal cortical dysplasia type II subtypes in latino population. Upon analyses, we found no statistically significant difference in post-surgical outcome between patients with subtypes of type II focal cortical dysplasia.it comes to our attention that although most reports showed that this kind pathology has a poor outcome, most of our patients  Engel’s classification ranged from class I to II.Our study suggests that the histologic subtype of type II focal cortical dysplasia is not predictive of post-surgical outcome with respect to seizure frequency. The paucity of studies that differentiated among subtypes of type I focal cortical dysplasia when assessing surgical outcome also corroborates this conclusion. Nonetheless, these subtypes may have clinical relevance for other outcome measures that have yet to be explored in this population. Funding: CAMELICE