Clinical and radiological findings in predicting the success of endoscopic third ventriculostomy

Introduction: Hydrocephalus is a condition characterized by an imbalance between cerebrospinal fluid production and absorption. In addition to shunt surgery, endoscopic third ventriculostomy (ETV), a relatively more physiological and minimally invasive approach, has gained widespread acceptance. Several scoring systems based on preoperative clinical parameters—such as patient age, hydrocephalus etiology, and prior shunt history—have been developed to estimate the likelihood of ETV success. This study aims to improve predictive performance by integrating radiological parameters into these existing models. Materials and Methods: A retrospective review was conducted on the medical records of 208 patients under 19 years of age who underwent ETV between 2012 and 2024 at the Departments of Neurosurgery, Pamukkale University Faculty of Medicine, and Pediatric Neurosurgery, Gazi University Faculty of Medicine. Patients lacking six-month follow-up, those who underwent shunt insertion or revision during ETV, and those who received choroid plexus cauterization were excluded. Variables analyzed included patient age at surgery, surgical indication, shunt history, and preoperative magnetic resonance imaging (MRI) findings: tuber cinereum bowing, Evans index, transependymal edema, and lamina terminalis bowing. ETV was deemed successful in patients who did not require further surgical intervention for hydrocephalus and who survived for at least six months postoperatively. Results: In the final cohort of 167 patients, univariate analysis revealed significant associations between ETV success and patient age, hydrocephalus etiology, and shunt history. However, no significant relationship was observed with Evans index or transependymal edema. Notably, the presence of lamina terminalis bowing (LTB) was strongly associated with successful outcomes (p <0.001). Although tuber cinereum bowing (TCB) showed significance in univariate analysis (p = 0.011), it did not maintain statistical significance in multivariate models that included the ETV Success Score (ETVSS) and LTB (p = 0.129). Discussion: Our findings support the predictive utility of the ETVSS and suggest that incorporating lamina terminalis bowing into preoperative assessment may enhance its prognostic accuracy. The combined evaluation of ETVSS and LTB could provide valuable guidance in clinical decision-making regarding ETV candidacy.