RT Journal Article
SR Electronic
T1 The Overlap Index as a means of evaluating early tau-PET signal reliability
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP jnumed.121.263136
DO 10.2967/jnumed.121.263136
A1 Jeyeon Lee
A1 Brian J. Burkett
A1 Hoon-Ki Min
A1 Emily S. Lundt
A1 Sabrina M. Albertson
A1 Hugo Botha
A1 Matthew L. Senjem
A1 Jeffrey L. Gunter
A1 Christopher G Schwarz
A1 David G Jones
A1 David S. Knopman
A1 Clifford R. Jack, Jr.
A1 Ronald C. Petersen
A1 Val J. Lowe
YR 2022
UL http://jnm.snmjournals.org/content/early/2022/03/17/jnumed.121.263136.abstract
AB In tau positron emission tomography (tau-PET), a reliable method to detect early tau accumulation in the brain is crucial. Noise, artifacts, and off-target uptake impede detection of subtle true positive ligand binding. We hypothesize that identifying voxels with stable activity over time can enhance detection of true positive tau. Methods: 339 participants in the clinical spectrum ranging from clinically unimpaired to Alzheimer’s Disease Dementia underwent ≥2 serial tau-PET scans with flortaucipir. The “overlap index” (OI) method was proposed to detect spatially identical, voxel-wise standardized uptake value ratio (SUVR) elevation when seen sequentially in serial tau-PET scans. The association of OI with tau accumulation, clinical diagnosis, and cognitive findings was evaluated. Results: OI showed good dynamic range in the low-SUVR window. Only OI was able to identify subgroups with increasing tau-PET signal in low SUVR meta-ROI groups. OI showed improved association with early clinical disease progression and cognitive scores versus meta-ROI SUVR measures. Conclusion: OI was more sensitive to tau signal elevation and longitudinal change than standard ROI measures, suggesting it is a more sensitive method for detecting early, subtle deposition of neurofibrillary tangles.