Visual interpretation of [18F]Florzolotau Tau-PET imaging for differentiating alzheimer's disease and progressive supranuclear palsy.

INTRODUCTION: Tau accumulation in the brain is a hallmark of both Alzheimer's disease (AD) and progressive supranuclear palsy (PSP), complicating differential diagnosis. The novel [18F]Florzolotau tauPET enables invivo detection. This study tests a visual reading approach on [18F]Florzolotau PET for reliably separating AD from PSP and assessing its clinical usefulness. METHODS: Eightynine participants of Aβpositive AD, Aβnegative PSP, and cognitively unimpaired controls (CU) underwent [18F]​Florzolotau PET, [18F]​Florbetapir amyloidPET, and MRI. Visual interpretation of the tau-PET scans was performed using a colormap-based method, dividing the brain into AD-specific regions and PSP-specific regions. Regional tau uptake was scored visually, and the results were compared with SUVr values from quantitative analysis. Decision tree analysis was used to classify patients based on visual scores. RESULTS: The study found significant differences in visual scores between the CU, AD, and PSP groups, particularly in the AD-specific and PSP-specific regions. Visual assessment of tau uptake moderately correlated with SUVr values, especially in AD-specific regions. The decision tree model using visual scores accurately classified CU, AD, and PSP patients, with sensitivity and specificity rates exceeding 85%. Interobserver agreement for visual scoring was high, supporting the reliability of this method in clinical settings. CONCLUSION: Visual interpretation scoring system of [18F] Florzolotau tau-PET reliably distinguishes AD from PSP, shows strong correlations with diagnoses, and is simpler than quantitative analyses for routine practice. Larger cohorts must confirm accuracy, refine the method, and assess its ability to grade disease severity.