Predictors of shunt failure in adult post-hemorrhagic and tumor-related hydrocephalus treated with flow-regulated programmable valves.

objectivePost-hemorrhagic (PHH) and tumor-related hydrocephalus (TRH) remain challenging to treat in adults, with shunt failure remaining a major concern. Evidence supporting programmable valves in this setting is limited and inconclusive. This study aims to compare the outcomes of ventriculoperitoneal shunting (VPS) using programmable flow-regulated valves (FV) in patients with PHH and TRH, with a focus on valve performance and predictors of shunt failure and revision surgery. We retrospectively analyzed adult patients treated with VPS using programmable FVs for tetraventricular PHH and TRH. Outcomes included radiological improvement, complication rates, need for valve setting adjustments, and associations between preoperative factors and postoperative outcomes. A total of 37 (57.8%) patients with PHH and 27 (42.2%) with TRH were included in the analysis. Overall radiological improvement was achieved in 53 (82.8%) patients. TRH cases required significantly more valve adjustments (n = 16; 59.2% vs. n = 17; 45.9%, p = 0.041) and showed higher shunt failure rates, particularly with extra-axial tumors in the anterior and posterior cranial fossae (p < 0.001). Overdrainage and infections occurred exclusively in PHH. Age, gender, initial valve settings, and baseline imaging were not predictive of outcomes. Programmable FVs represent a reliable strategy for the treatment of PHH and TRH in adults, demonstrating high clinical and radiological success with low complication rates. Tumor location, rather than baseline patient or radiological characteristics, emerges as the main predictor of shunt failure. These findings support individualized shunt management and underscore the need for prospective validation to confirm these results and optimize long-term outcomes.