Endoscopic third ventriculostomy for shunt malfunction.

Dear Editor,

We found the article by Neils et al.[1] very interesting. This study included 20 consecutive cases of shunt malfunction that were managed with endoscopic third ventriculostomy (ETV). The authors reported an overall success rate of 70% with the highest success rate in ligated shunt group but the lowest success in patients managed with shunt removal and external ventricular drainage insertion.

During the past 3 years we manage shunt malfunction of children older than 1 year with ETV. Our protocol is to perform ETV, leave the shunt at its place and perform choroid plexus cauterization (CPC) in patients with dilated ventricles. Due to catheter attachment to underlying brain tissue or choroid plexus shunt removal may be associated with hemorrhagic complications. Therefore we leave the shunt system, do not insert external catheter drainage, which may decrease the success rate of ETV, and observe the child very closely after ETV for the signs and symptoms of raise intracranial pressure. Regarding the high success rate of ETV subsequent to shunt malfunction, we perform ETV/CPC in shunt infection cases with informed consent from the parents and postpone new shunt insertion only in patients with ETV/CPC failure. The success rate of ETV in shunt infection group is not as high as shunt malfunction group but is an alternative in some patients not to have shunt anymore. Early failure of ETV with open ventriculostomy site is managed with repeated lumbar puncture that can help the ostomy work well and increase the success rate. It seems to us that patients with shunt malfunction or infection, who have predominantly obstructive hydrocephalus, can use ETV/CPC as an alternative with acceptable success rate.