The Effects of Endoscopic Third Ventriculostomy Versus Ventriculoperitoneal Shunt on Neuropsychological and Motor Performance in Patients with Idiopathic Normal Pressure Hydrocephalus-ENVENTOR-iNPH: Study Protocol.

Background: Idiopathic normal pressure hydrocephalus (iNPH) is a progressive neurological disorder characterized by cognitive decline, gait disturbances, and urinary incontinence. Surgical interventions such as ventriculoperitoneal shunt (VPS) and endoscopic third ventriculostomy (ETV) are the primary treatment options. While VPS is the standard of care, ETV offers a minimally invasive alternative with potentially fewer complications. However, comparative evidence regarding their impact on cognitive, motor, and structural outcomes remains limited. This study, titled ENVENTOR-iNPH (endoscopic ventriculostomy versus shunt on neuropsychological and motor performance in patients with iNPH), aims to address this gap through a rigorously designed comparative protocol. Methods: This protocol is designed as a multicenter, randomized, controlled trial (ENVENTOR-iNPH) to compare the effects of ETV and VPS in patients diagnosed with iNPH. The study will enroll 100 patients aged 60 years or older, randomly assigned to undergo ETV (n = 50) or VPS (n = 50). Preoperative and postoperative evaluations will include comprehensive cognitive and motor assessments, standardized quality-of-life instruments, and advanced neuroimaging techniques such as MRI with flowmetry and diffusion tensor imaging (DTI). Functional outcomes will also be evaluated using navigated transcranial magnetic stimulation (nTMS) and wearable motion analysis systems. The objective of this study is to compare the efficacy and safety of ETV versus VPS in restoring cognitive and motor performance in patients with iNPH. Results: Primary outcomes include cognitive and motor function improvements. Secondary endpoints are surgical complications, hospital stay duration, and changes in quality of life. Neuroimaging will assess changes in white matter integrity and cerebrospinal fluid dynamics, while nTMS will provide insights into neuroplasticity and motor pathway recovery. ETV is hypothesized to demonstrate clinical outcomes comparable or superior to VPS, particularly in terms of complication reduction and hospital recovery metrics. Conclusions: The ENVENTOR-iNPH protocol establishes the framework for a comprehensive, multicenter study comparing ETV and VPS in iNPH patients. The findings from this initial study will inform the design of larger-scale multicenter trials, guide clinical decision making, and potentially position ETV as a preferred treatment option for eligible patients.