Introduction
Subdural hygroma is a known complication of Sylvian fissure arachnoid cysts (SACs). However, most of the data in the literature refer to spontaneous or posttraumatic occurrence of subdural hygromas, regarded as either a favorable or an unfavorable event. Little is known about this phenomenon as a consequence of the surgical management of SACs. The present study was carried out to evaluate the significance of postoperative subdural hygromas in children with temporal arachnoid cysts, who have been treated with craniotomy and wide marsupialization of the cystic membrane.