Neurosurgery 93:555–562, 2023
Overdrainage is a widely reported complication representing common indication for shunt revision. Despite recent advances in valve design, repeated shunt revisions represent burden on healthcare systems.
OBJECTIVE: To investigate the efﬁciency of a novel gravity unit–assisted programmable valve “M.blue” in pediatric hydrocephalus using clinical and biomechanical analyses.
METHODS: This retrospective single-center study included pediatric patients who received M.blue valve between April 2019 and 2021. Several clinical and biomechanical parameters were documented including complications and revision rates. Flow rate, functional assessment in vertical and horizontal positions, and extent of depositions inside valve were analyzed in explanted valves.
RESULTS: Thirty-seven M.blue valves in 34 pediatric patients with hydrocephalus (mean age 2.82 ± 3.91 years) were included. Twelve valves (32.4%) were explanted during a follow-up period of 27.3 ± 7.9 months. One-year survival rate of 89% and overall survival rate of 67.6% with a valve survival average of 23.8 ± 9.7 months were observed. Patients with explanted valves (n = 12) were signiﬁcantly younger, with 0.91 ± 0.54 years of age in average (P= .004), and showed signiﬁcantly more adjustments difﬁculties (P= .009). 58.3% of explanted valves showed deposits in more than 75% of the valve surface despite normal cerebrospinal ﬂuid ﬁndings and were associated with dysfunctional ﬂow rate in vertical, horizontal, or both positions.
CONCLUSION: The novel M.blue valve with integrated gravity unit is efﬁcient in pediatric hydrocephalus with comparable survival rate. Deposits inside valves could affect its ﬂow rate in different body positions and might lead to dysfunction or difﬁculties in valve adjustments.