Scintillation camera apparatus capable of quantitatively eliminating

Abstract

In a scintillation camera apparatus, a gamma-ray scattering signal component is removed from gamma-ray spectral energy distribution data. A scattering component removing method first detects an 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. Then only first partial radiation from the radioisotope passing through a first energy range determined in relation to the specific energy level of the radioisotope is detected, thereby producing a first count value of the partial radiation. Partial second and third radiation from the radioisotope passing through second and third energy ranges positioned at both ends of the first energy range and also each having a width narrower than that of the first energy range are then detected, thereby producing second and third count values of the second and third partial radiation. These first to third radiation detecting steps are simultaneously performed. An amount of a scattering radiation component contained in the first partial radiation from the radioisotope passing through the first energy range based on both the second and third count values of the second and third partial radiation is then inferred. The amount of the scattering signal component is then subtracted from the first partial radiation passing through the first energy range, whereby the scattering signal component is removed from the entire radiation detecting signal.