Abstracts

Rationale: We followed some factors related to epilepsy to explain differences in memory changes after temporal lobe epilepsy surgery. Methods: Patients (30 males, 13 females; aged 17-49) with refractory temporal lobe epilepsy were followed for five years. We have collected the following data as predictors; pre-surgical neuropsychology, febrile seizures occurrence, familial occurrence of epilepsy, Wada test results, MRI, hemisphere dominancy and Engel’s classification. The memory development between two periods of time was assessed by the Wechsler Memory test. We have considered the memory changes between the pre-surgical and post-surgical assessments and the assessment after five years. Results: We distinguished unchanged, worsened and improved patients within the first and second period. The cut point for ranging the worsened/improved group was 1 SD below/above the total group mean. Group A: 21 patients unchanged in both periods. Group B: 8 patients unchanged in the first and worsened in the second period. Group C: 7 improved in the first and worsened in the second period. Group D: 7 patients got worse in the first and improved in the second period. The MQ change correlated negatively with age in the second period (p=0.012). The results below show the most important differences among the subgroups. There are significant, when stated, or remarkable differences. The SEEG is more frequent in group B (63 %) compared with group C (14 %). The GTCS is more frequent in group C (100 %) compared with 57 - 71 % in other groups. The MRI findings: The MTS is less frequent in group D (29 %) compared with more than 70% in other groups. The type of surgery: The amygdalo-hippocampectomy is more frequent in group B (50%) compared with 14 - 33 % in other groups. The AMTR is less frequent in group B (25 % compared with 43 - 57 %). The lesionectomy is more frequent in group D (43% compared with 19 - 29 %). The diskrepancy between neuropsychological assessment and seizures onset zone is more frequent in group D (71 %) compared with 11 - 29 % in other groups. Dominant hemisphere surgery is significantly less frequent in group A (19 %) compared with group B (63%). Engel’s classification: The first level is slightly more frequent in the group C (86 %) compared with 62 - 72 % in other groups. The third and worse levels group is more frequent in group A (29 %) compared with 0 - 14 % in the other groups. Results of Wada test show similar profile for groups A and B. Conclusions: The most frequent and continuous is group A, which constitutes a point of reference. Group B gets worse to a greater extent in the second period. There are patients with more complicated epilepsy and more frequent dominant hemisphere surgery. Group C shows a significantly low starting MQ values with a more frequent occurrence of the GTCS before surgery. The “down-up” group D shows a higher frequency of worsening neuropsychological assessment, more frequent lesionectomy and less frequent MTS findings. Our results indicate that the Engel’s classification results do not correlate with post-surgical memory development.