|
|
|||||||||
BASIC SCIENCE INVESTIGATIONS |
Research Program Radiological Diagnostics and Therapy, German Cancer Research Center, Heidelberg; Department of Experimental Surgery, University of Heidelberg, Heidelberg; Department of Medical Radiation Hygiene, Institute of Radiation Hygiene, Federal Office for Radiation Protection, Neuherberg; Department of Nuclear Medicine, Technische Universitaet Muenchen, Munich; and Department of Biomedical Engineering, University of Applied Sciences, Jena, Germany
For quantification of hepatic [18F]FDG uptake, the dual blood supply to the liver must be considered. In contrast to the arterial input, however, the portal venous blood supply to the liver cannot be monitored directly by PET because of the inaccessibility of the portal vein on PET scans. In this study, we investigated whether the dual hepatic input can be predicted from the measurable arterial input. Moreover, we assessed the effect of different input models on the rate constants of the standard 3-compartment model describing regional uptake of FDG. Methods: Dynamic FDG PET scanning was performed on 5 foxhounds. Activity concentrations in blood from the aorta and the portal vein were measured simultaneously using external circuits. After image reconstruction, timeactivity courses were determined from the aorta and the liver. The venous input was approximated by convolving the arterial input with a notional system function describing the dispersion of the arterial input on its way through the gastrointestinal tract. On the basis of these data, 5 different hepatic input models, which pertain to a single-input as well as a dual-input scenario, were statistically compared with regard to the adequacy of the model fits to liver data and to differences in the estimated rate constants. Results: Portal venous input to the liver could be approximated by convolving the arterial input function with a system function. From this function, a mean transit time of 25 s was computed for FDG to pass through the gastrointestinal tract. According to the statistical analysis, dual-input models were superior to their single-input counterparts. However, differences in the rate constants estimated for the 5 input models were in the same order as interindividual variations within the different model groups. For the dephosphorylation rate constant, a consistent value of 0.05 ± 0.01 min-1 was found. Conclusion: Dual-input models proved to be superior to single-input models with respect to the adequacy of FDG model fits to normal liver data. However, the hepatic blood supply may be approximated by the arterial input function as well, especially for the evaluation of liver lesions mainly fed by the hepatic artery.
Key Words: PET liver tissue dual hepatic blood supply FDG modeling
This article has been cited by other articles:
![]() |
E. E. Stewart, X. Chen, J. Hadway, and T.-Y. Lee Correlation between Hepatic Tumor Blood Flow and Glucose Utilization in a Rabbit Liver Tumor Model Radiology, June 1, 2006; 239(3): 740 - 750. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Iozzo, F. Geisler, V. Oikonen, M. Maki, T. Takala, O. Solin, E. Ferrannini, J. Knuuti, and P. Nuutila Insulin Stimulates Liver Glucose Uptake in Humans: An 18F-FDG PET Study J. Nucl. Med., May 1, 2003; 44(5): 682 - 689. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. L. Munk, S. Keiding, G. Brix, M. E. Bellemann, S. I. Ziegler, and U. Haberkorn Quantification of 18F-FDG Uptake in the Liver Using Dynamic PET J. Nucl. Med., March 1, 2002; 43(3): 439 - 441. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | RSS | TABLE OF CONTENTS |
| JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY | THE JOURNAL OF NUCLEAR MEDICINE |