ABSTRACT
INTRODUCTION Arachnoid cysts are benign congenital lesions more frequently encountered in children. According to the literature, 60% to 80% of these malformations are diagnosed in patients under the age of 16 years (1), the largest proportion of them in the first two years of life (2). Although these lesions are reported to have an incidence of 1% of intracranial space occupying lesions in most reports (2), studies based on neuroimaging or autopsy observations in large series indicate lower incidence ranging from 0.17 (3) to 0.3% (4). Males are affected approximately twice more than females. Arachnoid cysts can be found anywhere along the cerebrospinal axis, including the spinal spaces, although with a lower frequency in this compartment.
