Development of target centered arc apparatus for neurosurgical stereotactic procedures

Abstract

Introduction. The purpose of this study was to survey the prevalence of epilepsy in the urban population of São José do Rio Preto, a medium-sized city, 360,000 inhabitants, at northwest of São Paulo state, Brazil.Method: This population cross-sectional epidemiological study was carried out into two stages. The first was to access validation of the screening questionnaire on a neighborhood of the city; the second was the study of the prevalence in a randomly, stratified large-scale survey on the population of the city. A gold standard protocol, clinical history and neurological examination, was used to diagnose all the positive cases. The false negative cases were obtained after the validation of results by a mathematical model. For assessing prevalence Chi-square test and Confidence Interval (CI 95%) were used to analyze the results (p-value ≤ 0.05).Results: The Validation of the screening questionnaire showed a sensitivity of 95.83% and a specificity of 97.8%. There were 17,293 individuals in the studied sample; the distribution according to sex, age group and race was similar to the general population. Lifetime crude prevalence of epilepsy was 18.6/1000 inh. (CI 95%;16.6-20.6); 8.2(CI 95%;6.8-9.5) for active and