Hybrid PET/MRI Imaging of Alzheimer's Disease Based on <sup>18</sup>F-AV-1451

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disorder characterized by cognitive dysfunction, decline in daily living abilities, and behavioral changes, imposing a significant economic and social burden worldwide. One of the primary pathological hallmarks of AD is the accumulation of neurofibrillary tangles formed by hyperphosphorylated tau protein. Positron emission tomography/magnetic resonance imaging (PET/MRI) provides detailed structural and functional information along with specific protein distributions, making it an increasingly valuable tool for AD diagnosis and research. ¹⁸F-AV-1451 is a radiotracer specifically designed for tau protein detection in PET imaging of brain tissue. This study presents a detailed protocol for the radiosynthesis of ¹⁸F-AV-1451, patient preparation, PET/MRI image acquisition techniques, and its potential applications in AD evaluation. ¹⁸F-AV-1451 PET/MRI could aid neurologists in diagnosing AD, assessing disease severity, and gaining insights into its pathological mechanisms. In conclusion, this protocol provides a sensitive, comprehensive, and non-invasive approach for the evaluation of AD, offering valuable insights into disease progression and pathology.