Brain tumors as a cause of late-onset epilepsy
Introduction, patients and methods. We made a study of 223 patients with epileptic seizures which started when the patient was aged over 25 years (late onset), who were admitted to the National Institute of Neurology and Neurosurgery of La Habana, Cuba, over a period of ten years. The patients were divided into three groups according to age: from 25 to 39, from 40 to 59 and over 60 years. They formed two etiological groups—tumour and non-tumour—to evaluate the possible relationship with clinical variables and the results of complementary tests. Results. Of all the patients of groups 25 to 39 and 40 to 59 years. Over half the causes were of undefined cause. Of those in whom the cause was known, the most frequent cause of presentation was a tumour. Although vascular and degenerative causes were most frequent in the over 60 age group, cerebral tumours made up a significant percentage. We found that the presence of localizing signs on neurological examination or neuropsychological study and the occurrence of focal activity on the electroencephalogram were associated with the presence of a tumour, although their absence did not exclude this aetiology. There was no association with the type of seizures seen. Conclusion. Computerized axial tomography was very useful in the diagnosis of these tumours. However, a large percentage of patients required from two to four studies to establish the diagnosis.
Resultados En el total de los pacientes y en los grupos de 25 a 39 y de 40 a 59 años, más de la mitad de los casos no tuvieron causa definida y entre los de etiología definida la tumoral fue la de mayor frecuencia de presentación. Aunque en el grupo de 60 años o más fueron más frecuentes las causas vascular y degenerativa, los tumores cerebrales representaron un porcentaje significativo. Se encontró que la existencia de signos focales en el examen neurológico o en el estudio neuropsicológico, así como la aparición de un modelo electroencefalográfico de sufrimiento focal, estaban relacionados con la presencia de la causa tumoral, aunque la ausencia de estos elementos no excluyó esta etiología. El tipo de crisis no presentó asociación.
Conclusión La tomografía axial computarizada resultó de gran valor para el diagnóstico de los tumores, sin embargo, un porcentaje importante de los pacientes requirió entre dos y cuatro estudios para definir el diagnóstico
