Study Safety and Efficacy of Deep Brain Stimulation (DBS) and Cervical Deep Lymphoid-venous Anastomosis (LVA) in Alzheimer's Disease

Inclusion criteria

• Meeting the diagnostic criteria for dementia formulated by the National Institute on Aging-Alzheimer's Association (NIA-AA).
• Clinical Dementia Rating (CDR) score of 3 points.
• Ability to ambulate independently or with the aid of a walker/cane.
• Adequate visual and auditory capacity to cooperate with examinations and treatment.
• Voluntary participation with written informed consent provided by both the subject and their legal guardian.

Exclusion criteria

• Pre-existing abnormal brain structure (e.g., tumor, cerebral infarction, hydrocephalus, or intracranial hemorrhage).
• Comorbidity with other neurological disorders such as multiple sclerosis, epilepsy, or Parkinson's disease.
• Psychiatric disorders: e.g., anxiety, depression, other affective disorders, or drug-induced psychosis.
• Severe internal diseases, currently using respiratory/cardiovascular/anticonvulsant/psychotropic drugs, or clinically significant gastrointestinal, renal, hepatic, respiratory, infectious, endocrine, or cardiovascular diseases, cancer, alcoholism, or substance addiction.
• Severe auditory or visual impairment.
• Clinical comorbidities with life expectancy \<2 years.
• History of cranial surgery.
• Contraindications to MRI or transcranial alternating current stimulation (tACS) (e.g., cardiac pacemaker, post-deep brain stimulation surgery).
• Eczema or sensitive skin.
• Familial Alzheimer's disease.
• Other types of dementia: e.g., vascular dementia, Lewy body dementia, frontotemporal dementia, or infectious dementia;
• Any other condition deemed by the investigator as unsuitable for the study