Endoscopic third ventriculostomy for idiopathic normal pressure hydrocephalus

Initially reported for normal pressure hydrocephalus in 1999 1).

Mechanistically, it is difficult to explain why ETV would work for NPH, but it has been advocated by some 2) in highly selected patients, using nonvalidated outcome measures, quoting post-op improvement in 69% of patients. At this time, ETV should not be considered a first-line treatment for most cases of NPH.


ETV and VPS did not differ significantly regarding their failure rate for iNPH, while ETV showed a significantly lower complication rate than VPS. However, the data available is scarce with only one RCT investigating this important matter. Further well-designed trials are necessary to investigate the clinical outcome of ETV in iNPH 3)


The only randomized trial of endoscopic third ventriculostomy (ETV) for idiopathic normal pressure hydrocephalus (iNPH) compares it to an intervention which is not a standard practice (VP shunting using a non-programmable valve). The evidence from this study is inconclusive and of very low quality. Clinicians should be aware of the limitations of the evidence. There is a need for more robust research on this topic to be able to determine the effectiveness of ETV in patients with iNPH 4).

1)
Mitchell P, Mathew B. Third ventriculostomy in normal pressure hydrocephalus. Br J Neurosurg. 1999; 13:382–385
2)
Gangemi M, Maiuri F, Naddeo M, et al. Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus: an Italian multicenter study. Neurosurgery. 2008; 63:62–7; discussion 67-9
3)
Greuter L, Schenker T, Guzman R, Soleman J. Endoscopic third ventriculostomy compared to ventriculoperitoneal shunt as treatment for idiopathic normal pressure hydrocephalus: a systematic review and meta-analysis. Br J Neurosurg. 2022 Dec 20:1-7. doi: 10.1080/02688697.2022.2149697. Epub ahead of print. PMID: 36537195.
4)
Tudor KI, Tudor M, McCleery J, Car J. Endoscopic third ventriculostomy (ETV) for idiopathic normal pressure hydrocephalus (iNPH). Cochrane Database Syst Rev. 2015 Jul 29;7:CD010033. doi: 10.1002/14651858.CD010033.pub2. Review. PubMed PMID: 26222251.