Higher Failure of Endoscopic Third Ventriculostomy in Infants: The "Distensible" Skull Is the Culprit.

The efficacy of endoscopic third ventriculostomy (ETV) in childhood strongly correlates with age. Reasons for the higher failure rate in infants are under debate but the "distensible" head with its immature skull (which would prevent an adequate flow through the ETV and/or a sufficient pressure gradient between the cortical subarachnoid spaces and the venous sinuses) has been suggested as a possible cause. Our evidence of spontaneous conversion of a failed, but always patent, third ventriculostomy into an effective one occurring in a child after maturation of the skull supports this hypothesis.