e-Περιοδικό Επιστήμης & Τεχνολογίας

e-Journal of Science & Technology, (e-JST)


The use of Modulation Transfer Function as an Overall Quality Control parameter in PET/CT

A. Samartzis1, G. Fountos2, I. Kalatzis2, C. Michail3, A. Zanglis4, D. Cavouras2, I. Datseris1, E. Kounadi5, D. Vattis6, I. Kandarakis2 and G. Nikiforidis3

1 Nuclear Medicine Department, “EVANGELISMOS” General Hospital Ypsilantou 45-47, 10676 Athens, Greece

2 Department of Medical Instruments Technology Technological Educational Institution of Athens Ag. Spyridonos, Aigaleo, 122 10 Athens, Greece

3 Department of Medical Physics, Medical School University of Patras, 265 00 Patras, Greece

4 Nuclear Medicine Department, “PAMMAKARISTOS” General Hospital Iakovaton 43, 111 44 Athens, Greece

5 Department of Medical Physics, “ALEXANDRA” General Hospital Vasilisis Sofias 80, 11528, Athens, Greece

6 Department of Physics/Chemistry and Materials Technology, Technological Educational Institute (TEI) of Athens Ag. Spyridonos, Aigaleo, 12210 Athens, Greece

 Corresponding author: samartzis@ath.forthnet.gr

 Abstract. The Modulation Transfer Function (MTF) is an important parameter for the characterization of image quality and the signal transfer properties of an imaging system. To develop a new method for MTF determination of PET/CT in three dimensions (3D), a novel and highly uniform, film based flood source using 18F-FDG has been prepared. The source was placed between PMMA blocks of various thicknesses, and imaged in a GE Discovery-ST, PET/CT system. MTF was then calculated from the line spread function (LSF) profile of the film. The film was prepared by immersing silica gel matrix, Al foils (5×10cm Fluka) in 18F-FDG bath solution. The effects of different reconstruction algorithms and the shape of the scanned object on MTF were investigated. By this method the alignment of PET and CT in the fused image was investigated as well. Hence the MTF can be used as an overall quality control parameter in PET/CT.

 Keywords: PET/CT, Line Spread Function (LSF), Modulation Transfer Function (MTF), reconstruction algorithms, quality control.