Endoscopic treatment of quadrigeminal cistern arachnoid cysts.

Five patients with arachnoid cysts of the quadrigeminal cistern treated by endoscopic fenestration are reported and another eleven well-documented cases from the literature are reviewed. Among the five personal cases four were children and one was adult; the cyst fenestration was performed from the lateral ventricle in three cases and from the third ventricle in two. In four patients the endoscopic treatment resulted in clinical remission, whereas a two-month-old baby later required a shunt. The lateral ventricle-cystostomy and the third ventricle-cystostomy (according to the cyst extent) are the best endoscopic procedures, whereas the cyst fenestration through a suboccipital supracerebellar approach is no longer used. The rate of cured or improved patients after endoscopic surgery (14/16 or 87.5%) was rather similar to that of a group of twenty patients treated by traditional surgery (craniotomy and cyst excision and/or shunt) (85%). These data confirm that endoscopic fenestration of quadrigeminal cistern cysts must be performed as the first procedure because it is less invasive and avoids shunt dependency.