The goal of this clinical trial is to To demonstrate the Safety and Efficacy of dcLVA Surgery for the Treatment of Alzheimer's Disease. Patients who meet the inclusion and exclusion criteria and consent to participate will be randomly assigned to either the experimental group (receiving dcLVA surgery plus standard medication) or the control group (receiving standard medication alone) Participants will: Undergo cognitive assessment and brain MRI assessment; Undergo a lumbar puncture; Undergo an injection of 20ml of gadodiamide contrast agent at a concentration of 0.5 mmol/L (1ml gadodiamide: 20ml 0.9% saline). Primary Outcome Measures: The change in the sum of Clinical Dementia Rating Scale (CDR) scores at 12-month in relative to baseline