Abstract
This article reviews the historical progression of ventriculoperitoneal shunt valve designs with the goal of providing an understanding of their functionality and failure mechanisms. While shunting is the predominant treatment for hydrocephalus, the statistics of overall shunt failure remain high, and valve failure is responsible for a significant percentage of revision surgeries. Therefore, this review spans valve evolution from an engineering perspective with an emphasis on discussing potential failure mechanisms and patient-specific valve selection. Information is provided on the importance of valves in hydrocephalus treatment with discussion on each class of valves and their advantages and shortcomings. Substantial development over decades has significantly improved valve functionality, and ongoing research continues to provide more robust valves and shunt systems for hydrocephalus management.