ABSTRACT: One of the strengths of PET is the ability to measure regional tracer concentrations, which is the basis of a quantitative evaluation of patient studies. Parameters such as the standardized uptake value (SUV) or transport constants derived from kinetic modeling are commonly used for this purpose. The quantitative accuracy strongly depends on accurate calibration of the scanner, which is commonly performed with suitable phantoms. While this calibration procedure ensures quantitatively correct results in geometrically comparable phantoms, it still leaves questions to be asked regarding its reliability for in-vivo measurements due to different scatter distribution as well as tracer distribution in phantoms compared to patient scans.
It was therefore the aim of our study to investigate the actual in-vivo accuracy of a phantom-based scanner cross-calibration against a well-counter by comparison of the tracer concentration in the patient’s urine as determined by the PET system to the concentration measured in a well-counter.
50th German Conference on Nuclear Medicine; 04/2012