Scintillation camera apparatus capable of quantitatively eliminating scattering signal components by setting multiple window and method for quantitatively eliminating scattering signal components

摘要

In a scintillation camera apparatus, a gamma-ray scattering signal component (As(x, y)) is removed from gamma-ray spectral energy distribution data (Ct(x, y)). A scattering component removing method is characterized by comprising the steps of: detecting entire radiation emitted from a radioisotope having a specific energy level and injected into a biological body under medical examination to produce an entire radiation detecting signal; detecting only first partial radiation from the radioisotope passing through a first energy range (W1) determined in relation to the specific energy level of the radioisotope, thereby producing a first count value of the partial radiation; detecting partial second and third radiation from the radioisotope passing through second and third energy ranges (W2:W3) positioned at both ends of the first energy range (W1) and also each having a width narrower than that of the first energy range (W1), thereby producing second and third count values of the second and third partial radiation, said first to third radiation detecting steps being simultaneously performed; inferring an amount of a scattering radiation component (As(x, y)) contained in the first partial radiation from the radioisotope passing through the first energy range (W1) based on both the second and third count values of the second and third partial radiation; and, subtracting the amount of the scattering signal component (As(x, y)) from the first partial radiation passing through the first energy range (W1), whereby the scattering signal component is removed from the entire radiation detecting signal.