| 1. |
- Mansor, Syahir, et al.
(författare)
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Parametric Methods for Dynamic (11)C-Phenytoin PET Studies.
- 2017
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Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 1535-5667 .- 2159-662X. ; 58:3, s. 479-483
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the performance of various methods for generating quantitative parametric images of dynamic (11)C-phenytoin PET studies was evaluated. Methods: Double-baseline 60-min dynamic (11)C-phenytoin PET studies, including online arterial sampling, were acquired for 6 healthy subjects. Parametric images were generated using Logan plot analysis, a basis function method, and spectral analysis. Parametric distribution volume (VT) and influx rate (K1) were compared with those obtained from nonlinear regression analysis of time-activity curves. In addition, global and regional test-retest (TRT) variability was determined for parametric K1 and VT values. Results: Biases in VT observed with all parametric methods were less than 5%. For K1, spectral analysis showed a negative bias of 16%. The mean TRT variabilities of VT and K1 were less than 10% for all methods. Shortening the scan duration to 45 min provided similar VT and K1 with comparable TRT performance compared with 60-min data. Conclusion: Among the various parametric methods tested, the basis function method provided parametric VT and K1 values with the least bias compared with nonlinear regression data and showed TRT variabilities lower than 5%, also for smaller volume-of-interest sizes (i.e., higher noise levels) and shorter scan duration.
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| 2. |
- Wolters, Emma E., et al.
(författare)
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A novel partial volume correction method for accurate quantification of [18F] flortaucipir in the hippocampus
- 2018
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Ingår i: EJNMMI Research. - : Springer Science and Business Media LLC. - 2191-219X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: Off-target binding in the choroid plexus (CP) may cause spill-in of the tau PET tracer [18F] flortaucipir into the adjacent hippocampus region. The impact of this spill-in on hippocampal uptake was assessed using a novel partial volume correction method (PVC). Methods: PVC was performed on 20 [18F] flortaucipir dynamic PET scans (10 probable AD and 10 controls). Volumes of interest (VOIs) were defined for both hippocampus and CP. The correlation between hippocampal and CP distribution volume (VT), with and without PVC, was determined. Both anatomically defined and eroded VOIs were used. Results: For controls, the correlation between hippocampal and CP VT was significantly reduced after using PVC along with an eroded VOI (r2 = 0.59, slope = 0.80 versus r2 = 0.15, slope = 0.15; difference: p < 0.05). The same was true for AD patients (p < 0.05). Conclusion: PVC together with an optimized hippocampal VOI resulted in effective reduction of CP spill-in and improved accuracy of hippocampal VT.
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