@article {Richard1063, author = {Jean-Christophe Richard and Marc Janier and Francois Decailliot and Didier Le Bars and Franck Lavenne and Veronique Berthier and Martine Lionnet and Luc Cinotti and Guy Annat and Claude Gu{\'e}rin}, title = {Comparison of PET with Radioactive Microspheres to Assess Pulmonary Blood Flow}, volume = {43}, number = {8}, pages = {1063--1071}, year = {2002}, publisher = {Society of Nuclear Medicine}, abstract = {Microsphere technique is the reference for assessment of pulmonary blood flow (PBF) but is destructive; PET, however, can determine PBF noninvasively. Comparisons of these 2 methods are scanty. Our study aimed at comparing these 2 techniques using a mathematic model taking into account the right ventricle in determining the transit time of a tracer through lung tissue. Methods: Ten normal pigs were investigated at baseline, during dobutamine infusion, and during 10 cm H2O of positive end-expiratory pressure. Under each condition, PBF was successively measured with PET (PET-PBF) and radioactive microspheres (MS-PBF). For PET-PBF, 2 mCi (74 MBq) 15O-labeled water were injected intravenously over 20 s and PET scanning was performed for 10 min. The input function was determined noninvasively from PET and invasively from mixed venous blood withdrawals. PET-PBF was computed using a mathematic model taking into account the right ventricle in determining the transit time of the tracer through lung tissue. For MS-PBF, 1 given isotope was injected under a given condition. PET-PBF and MS-PBF for 5 lung regions were compared. Results: PET-PBF significantly correlated with MS-PBF both over all experimental points (PET-PBF = 0.79 {\textperiodcentered} MS-PBF + 1,538; r = 0.79; P \< 0.001) and in separate lung regions. Invasive and noninvasive input functions also correlated significantly (r = 0.90; P \< 0.001). Simulations stressed the crucial role of the right ventricle to the transit time of tracer through lung tissue in the determination of PET-PBF. Conclusion: PBF can accurately be assessed using PET and a mathematic model taking into account the right ventricle in determining the transit time of a tracer through lung tissue. Noninvasive determination of the input function of the right ventricle is accurate and can readily be used for clinical applications.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/43/8/1063}, eprint = {https://jnm.snmjournals.org/content/43/8/1063.full.pdf}, journal = {Journal of Nuclear Medicine} }