Analysis of Cerebrospinal Fluid Dynamics in Normal Pressure Hydrocephalus

Inclusion Criteria: * Patients presenting with clinical symptoms consistent with normal pressure hydrocephalus (presence of gait disturbance accompanied by at least one of the following: cognitive impairment or urinary dysfunction) * Evans' ratio ≥ 0.3 on brain MRI Exclusion Criteria: * Patients who cannot undergo CSF drainage due to structural abnormalities of the lumbar spine * Contraindications to lumbar puncture and CSF drainage (e.g., local infection at the puncture site, suspected elevated intracranial pressure, platelet count \< 40,000/µL, or coagulopathy) * Coexisting neurological disorders that can also cause gait disturbance, such as Parkinson's disease, atypical parkinsonian syndromes, or vascular parkinsonism * Contraindications to MRI (e.g., presence of cardiac pacemakers, implantable defibrillators, or other non-MRI-compatible implantable medical devices)