Valve Failure in Ventriculoperitoneal Shunts of Neuro-Oncologic Patients: A Historical Cohort Study

OBJECTIVE: To investigate malfunctioning of ventriculoperitoneal shunt (VPS) valves in patients with brain tumors compared with patients with VPS for nontumoral etiologies to identify risk factors for shunt malfunction. METHODS: Medical charts of all adult patients who underwent VPS surgery for hydrocephalus between 2011 and 2016 were reviewed. Incidence and risk factors for revision surgery due to valve malfunction were identified in patients with brain tumors (group A) and patients without brain tumors (group B). RESULTS: Group A comprised 89 patients, and group B comprised 164 patients. The median follow-up time was 17 months for the entire cohort (9.4 months for group A vs. 25 months for group B, P< 0.001). VPS revision was performed in 60 patients (23.7%); 11 revisions involved valve failures necessitating valve replacement. Valve failures were significantly more common in group A (10 group A patients vs. 1 group B patient, P < 0.001). The distal or proximal shunt revision rate for reasons other than the valve was similar for both groups. Group A patients had a significantly higher cerebrospinal fluid protein level (44.5 mg/dL vs. 27.79 mg/dL, P< 0.05), and patients with valve failure had a 3-fold higher cerebrospinal fluid protein level compared with group A patients who experienced any type of shunt failure (96.3 mg/dL vs. 30.6 mg/dL, P < 0.05). CONCLUSIONS: Shunt malfunction occurred mainly in patients with brain tumors and high cerebrospinal fluid protein levels. These patients are at high risk of valve failure and should be closely observed for emergent valve revision.