Deep Cervical LymphatIc-Venous Anastomosis for Alzheimer's Disease

Inclusion Criteria: * Age 50-80 years (inclusive), regardless of gender. * Meeting the diagnostic criteria for Mild Cognitive Impairment or mild to moderate dementia due to Alzheimer's disease (according to the 2024 AA clinical diagnostic criteria for AD-related dementia). * Disease duration of 6 months or longer, with no clinical improvement after 3 months or more of conservative treatment. * MMSE score: 12-26. * Biomarker confirmation of AD: positive Aβ-PET and tau-PET, or positive cerebrospinal fluid biomarkers. * Having a reliable caregiver (providing companionship for ≥3 hours per day). * Signed written informed consent from the patient or legally authorized representative. Exclusion Criteria: * Contraindications to MRI, ICG angiography, or PET. * Contraindications to surgery or anesthesia, such as coagulation disorders (platelet count \<100×10⁹/L, INR \>1.7). * Comorbid major organ dysfunction, such as reduced left ventricular ejection fraction, severe hepatic or renal insufficiency (AST or ALT \>3 times the upper limit of normal; eGFR \<30 mL/min/1.73m²). * Intracranial structural lesions indicated by MRI, including brain tumors, cerebral infarction, intracranial hemorrhage, aneurysms, arteriovenous malformations, hydrocephalus, etc. * MRI findings suggestive of significant cerebral small vessel disease features: more than one lacunar infarction in the deep white matter and periventricular regions and/or white matter hyperintensity (WMH) with a Fazekas grade \>2, or the presence of ≥4 cerebral microbleeds. * Other causes of dementia, such as hypothyroidism or vitamin B12 deficiency. * Drug/alcohol addiction. * Severe psychiatric illness or suicide risk. * Comorbid medical conditions with a life expectancy of less than 1 year. * Participation in another interventional trial within the past 3 months. * Poor compliance or judged by the investigator as unsuitable for participation. * Patients receiving therapy with Lecanemab or Donanemab. * Other conditions that the researcher deems unsuitable for participation in this study.