Abstracts

Introduction: Patients with medically refractory epilepsy have surgery as their last resource to control seizures. Pre-surgical evaluation and the surgical treatment of neocortical epilepsy is one of the most challenging areas in epilepsy surgery (Hong, 2002). In some cases, these patients have non-lesional hippocampi revealed by magnetic resonance imaging (MRI) and most of them have memory problems. Our aim is to investigate if non-lesional hippocampi and memory impairment are associated.
Materials and methods: In the study 20 patients were included with neocortical temporal lobe epilepsy (NTLE) and without detectable hippocampal lesions on MRI who underwent a complete investigation, including neuropsychological assessment. As to detect any possible association between memory[rsquo]s deficits/ impairment and age of seizure onset, frequency, gender and location of epileptogenic hemisphere. Descriptive analysis and Fisher[rsquo]s exact tests were used as well.
Results: Significative associations, within memory deficit and patients with (NTLE) (p=0,00006) and non-lesional hippocampi, were found. Also, memory[rsquo]s impairment type (verbal or visual) when separately compared, shown no significant association. Higher memory impairment (85%) predisposition was shown when three tests were statistically combined. Memory impairment and age of seizure onset reported expressive association. The patients with age of seizure onset lower than 15 years pointed out a higher predisposition to demonstrate memory impairment (p=0,031).
Conclusion: The results suggests that NTLE patients with normal MRI showed higher predisposition to have memory deficit associated with age of seizure onset lower than 15 years old. Therefore, seizure[rsquo]s early appearance in these patients seems to be an important fact in memory impairment establishment.
[Supported by: Neurology Service-Neuropsychology Unit of Epilepsy Surgery Program - Hospital S[atilde]o Lucas da Pontif[iacute]cia Universidade do Rio Grande do Sul (PUCRS)]