BACKGROUND Monoventricular hydrocephalus is usually treated with extratheca
l shunting. However, today endoscopic fenestration of the septum pellucidum
seems to be a very useful and less invasive technique.
METHODS Five patients with monoventricular hydrocephalus have been treated
with neuroendoscopic techniques. In three cases with an excluded lateral ve
ntricle due to contralateral shunt overdrainage, the normal-sized ventricle
was first cannulated and fenestration of the septum pellucidum from the no
rmal to the enlarged lateral ventricle was performed.
RESULTS Complete remission of intracranial hypertension symptoms and decrea
se in size of the enlarged ventricle were observed in all five patients.
CONCLUSIONS Endoscopic fenestration of the septum pellucidum is the techniq
ue of choice for treating monoventricular hydrocephalus. We advise first ca
nnulating the normal lateral ventricle and then performing a septostomy fro
m it to the enlarged ventricle. This approach allows one to easily recogniz
e the protruding septum pellucidum and perform fenestration without difficu
lty using a direct trajectory. In exceptional cases of choroid plexus cyst
obstructing one foramen of Monro, fenestration of the cyst wall is sufficie
nt. (C) 1999 by Elsevier Science Inc.