TY - JOUR
T1 - Calibrated image-derived input functions for the determination of the metabolic uptake rate of glucose with [18F]-FDG PET
AU - Christensen, Anders N
AU - Reichkendler, Michala H
AU - Larsen, Rasmus
AU - Auerbach, Pernille
AU - Højgaard, Liselotte
AU - Nielsen, Henning B
AU - Ploug, Thorkil
AU - Stallknecht, Bente
AU - Holm, Søren
PY - 2014/4
Y1 - 2014/4
N2 - PURPOSE: We investigated the use of a simple calibration method to remove bias in previously proposed approaches to image-derived input functions (IDIFs) when used to calculate the metabolic uptake rate of glucose (Km) from dynamic [F]-FDG PET scans of the thigh. Our objective was to obtain nonbiased, low-variance Km values without blood sampling. MATERIALS AND METHODS: We evaluated eight previously proposed IDIF methods. Km values derived from these IDIFs were compared with Km values calculated from the arterial blood samples (gold standard). We used linear regression to extract calibration parameters to remove bias. Following calibration, cross-validation and bootstrapping were used to estimate the mean square error and variance. RESULTS: Three of the previously proposed methods failed mainly because of zero-crossings of the IDIF. The remaining five methods were improved by calibration, yielding unbiased Km values. The method with the lowest SD yielded an SD of 0.0017/min - that is, below 10% of the muscle Km value in this study. CONCLUSION: Previously proposed IDIF methods can be improved by using a simple calibration procedure. The calibration procedure may be used in other studies, thus obviating the need for arterial blood sampling, once the calibration parameters have been established in a subgroup of participants. The method has potential for use in other parts of the body as it is robust with regard to partial volume effects.
AB - PURPOSE: We investigated the use of a simple calibration method to remove bias in previously proposed approaches to image-derived input functions (IDIFs) when used to calculate the metabolic uptake rate of glucose (Km) from dynamic [F]-FDG PET scans of the thigh. Our objective was to obtain nonbiased, low-variance Km values without blood sampling. MATERIALS AND METHODS: We evaluated eight previously proposed IDIF methods. Km values derived from these IDIFs were compared with Km values calculated from the arterial blood samples (gold standard). We used linear regression to extract calibration parameters to remove bias. Following calibration, cross-validation and bootstrapping were used to estimate the mean square error and variance. RESULTS: Three of the previously proposed methods failed mainly because of zero-crossings of the IDIF. The remaining five methods were improved by calibration, yielding unbiased Km values. The method with the lowest SD yielded an SD of 0.0017/min - that is, below 10% of the muscle Km value in this study. CONCLUSION: Previously proposed IDIF methods can be improved by using a simple calibration procedure. The calibration procedure may be used in other studies, thus obviating the need for arterial blood sampling, once the calibration parameters have been established in a subgroup of participants. The method has potential for use in other parts of the body as it is robust with regard to partial volume effects.
U2 - 10.1097/MNM.0000000000000063
DO - 10.1097/MNM.0000000000000063
M3 - Journal article
C2 - 24335879
SN - 0143-3636
VL - 35
SP - 353
EP - 361
JO - Nuclear Medicine Communications
JF - Nuclear Medicine Communications
IS - 4
ER -