Dataset Information

Scan-Time Corrections for 80-100-min Standardizetd Uptake Volume Ratios to Measure the 18F-AV-1451 Tracer for Tau Imaging.

ABSTRACT: The 18F-AV-1451 PET tracer binds to tau, an Alzheimer's disease biomarker. The standardized uptake value ratio (SUVR) 80-100 min window is widely used to quantify tau binding, although 18F-AV-1451 continues increasing relative to a reference region in regions with tau deposition. Left uncorrected, acquisition time inaccuracies can lead to errors from -4% to 6% in 20-min SUVR measurements in subjects with Alzheimer's disease. In 40 subjects with scans from 75-115 min following 18F-AV-1451 injection, we created 20-min reconstructions (4×5 min) of start-times ranging from 75-85 min, as proxies of offset scans and calculated the mean in regions of interest (ROIs). We developed a segmented least squares (SLS) method to obtain error-minimizing weighting coefficients for 18F-AV-1451 ROIs that best predict SUVR 80-100 from weighted means of SUVRs from offset start-times. We compared residual errors of our SLS method to those in: 1) uncorrected offset 20-min-SUVRs; 2) the mean of five-min frames within the 80-100 window; and 3) a least-squares interpolation method. We evaluated errors induced by start-time offset on SUVRs for each method. TheSLS, which corrected using least-squares coefficients of 5-min components, consistently reduced errors across all offset starttimes. Effect size analysis for simulated clinical longitudinal 18F-AV-1451 drug trials showed that uncorrected 20-min offset SUVRs would require up to 20% more participants to detect treatment effects compared with using SLS. Correction of SUVR scan-time errors by SLS minimizes errors compared with other correction methods and may be extended to other scanners and tracers.

SUBMITTER: He M

PROVIDER: S-EPMC6475617 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Publications

Scan-Time Corrections for 80-100-min Standardizetd Uptake Volume Ratios to Measure the 18F-AV-1451 Tracer for Tau Imaging.

He Mark M Baker Suzanne L SL Shah Vyoma D VD Lockhart Samuel N SN Jagust William J WJ

IEEE transactions on medical imaging 20180917 3

The 18F-AV-1451 PET tracer binds to tau, an Alzheimer's disease biomarker. The standardized uptake value ratio (SUVR) 80-100 min window is widely used to quantify tau binding, although 18F-AV-1451 continues increasing relative to a reference region in regions with tau deposition. Left uncorrected, acquisition time inaccuracies can lead to errors from -4% to 6% in 20-min SUVR measurements in subjects with Alzheimer's disease. In 40 subjects with scans from 75-115 min followi ...[more]

PMID: 30235119

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Dataset Information

Scan-Time Corrections for 80-100-min Standardizetd Uptake Volume Ratios to Measure the 18F-AV-1451 Tracer for Tau Imaging.

Publications

Scan-Time Corrections for 80-100-min Standardizetd Uptake Volume Ratios to Measure the <sup>18</sup>F-AV-1451 Tracer for Tau Imaging.

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