Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by rapid progression, making early diagnosis and therapeutic intervention particularly challenging. This study aims to develop an integrated diagnostic framework that combines α-synuclein PET imaging with longitudinal MRI, enabling both precise disease characterization and early-stage screening. By identifying suitable candidates at an earlier phase, we seek to establish trial-ready patient cohorts and accelerate the development of disease-modifying therapies in collaboration with pharmaceutical partners. In addition to referrals from affiliated institutions, we will build a broad patient recruitment framework through online outreach, aiming to translate our MSA trial support system into clinical practice.