Five patients presented with symptoms related directly to pressure eff
ects from their cavum septum pellucidum with persistent or intermitten
t obstructive hydrocephalus. The most characteristic presenting sympto
ms were intermittent postural headache and postural loss of consciousn
ess. If cysts of the cavum septum pellucidum are symptomatic and stere
otactic cyst puncture or fenestration are ineffective, ventriculoperit
oneal shunting should be carried out before resorting to more radical
excision of the cyst.