This prospective study recruited 20 healthy volunteers and 50 patients diagnosed with Alzheimer's disease (AD) and mild cognitive impairment (MCI) according to clinical guidelines. Participants underwent AV45/AV-1 and AV1451 PET imaging to obtain information on Aβ protein deposition, tau protein distribution, and structural and functional information. The study aims to evaluate the value of multimodal imaging features in the diagnosis and progression assessment of AD, providing imaging evidence for novel treatment modalities such as lecanemab therapy and deep cervical vein-lymphatic anastomosis.