The Role of Tau Imaging in Parkinsonian Disorders
Purpose of Review
Differential diagnosis of atypical Parkinson syndromes (APS) is difficult as clinical presentations may vary and as there is a strong overlap between disease entities. Aggregations of misfolded and hyperphosphorylated tau proteins are the common denominator of many of these diseases.
Several tau targeting positron emission tomography (PET) tracers have been evaluated as possible biomarkers in APS in the recent years. For Parkinson’s disease, dementia with Lewy bodies, progressive supranuclear palsy, and corticobasal degeneration, promising results have been reported with regard to the ability to detect the presence of disease and to discriminate patients from controls. However, the discussion about the specificity of the first-generation radiotracers and their value in the clinical context is ongoing.
A combined interpretation of signal strength and distribution pattern in PET scans with first- and second-generation tracers may be helpful in clinical diagnosis and follow-up of patients with APS.
KeywordsTau PET Atypical Parkinson syndromes Flortaucipir THK-5351 PBB3
Compliance with Ethical Standards
Conflict of Interest
Jochen Hammes declares no potential conflict of interest. Alexander Drzezga reports grants and non-financial support from Siemens, personal fees and non-financial support from GE, grants, personal fees and non-financial support from AVID/Lilly, non-financial support from Piramal, outside the submitted work. Thilo van Eimeren received honoraria from Lilly Germany and Shire Germany and grants from the German Research Foundation (DFG), the Leibniz Association and the EU-Joint Program for Neurodegenerative Diseases (JPND).
Human and Animal Rights
All reported studies/experiments with human or animal subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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