A Peculiar Tau Accumulation Pattern Identified Via 18 F-Florzolotau PET Imaging in a Patient With Frontotemporal Dementia Caused by a Mutation in the MAPT Gene.

We reported imaging findings with a peculiar tau accumulation pattern in a 56 year-old woman with frontotemporal dementia caused by Q351R mutation in the microtubule-associated protein tau ( MAPT ) gene. She had a 10-year history of gradually worsening memory loss. 18 F-FDG PET demonstrated hypometabolism in medial temporal lobes, but 18 F-florbetapir PET manifested no abnormal amyloid beta deposition, which ruled out Alzheimer disease. 18 F-florzolotau PET showed tau proteins accumulated in medial temporal lobes, basal ganglia brainstem, and cerebellum. The pattern is different from other known MAPT gene mutation. Multitracer imaging can help differentiate between Alzheimer disease and frontotemporal dementia caused by MAPT mutation.