核医学イメージングにおける問題点とその対応

抄録

Since nuclear medicine imaging relies greatly on the scintillation camera quality controls, we emphasized floodfield uniformity, which is the most important factor among the various quality controls. Field uniformity checks the ability to produce accurate images of the relative radionuclide distribution in a patient, without this assurance, the phisician interpreting cannot be certain if all image abnormalities are attributable to the disease or to nonuniform performance of the camera. Second, to make the best image, we investigated three fundamental factors (image size, count density, film density) so as to detect the small Iesions. Size reduction to 16% of the real size appeared to be the best as regards image quality. Under the condition of image size reduction, a count density of 2,000 cpcm^2 was the most suitable. Film density was the best in the range form 1.0 to 1.2 to detect cold lesions and in the range from 0.8 to 1.0 to detect hot lesions.