| 摘要 |
<p>A diagnostic nuclear medical apparatus comprises a digital scintillation camera unit (90, 91, 92) for detecting radiation from a subject to provide a radiation count signal, a data processing unit (93, 96, 97, 98. 99, 100, 101) for converting the count signal from the camera unit into video information and a video imager (102) for receiving the video information and photographing the scintigram of the subject on an X-ray film. In the video imager, a test pattern is photographed on an X-ray film. A video to photographic density conversion characteristic of the developed X-ray film is measured, and the measured data is loaded into the data processing unit. The average value and standard deviation value of the radiation detection counts per pixel of a region-of-interest of the subject are computed, and the display upper count level is computed according to these values. A count to gray conversion table such that the upper count level corresponds to the maximum photographic density on the film and the conversion of the count to photographic density on the film becomes linear, is obtained according to the measured data and the upper count level. The count signals from the camera unit are converted according to a conversion table into video signals having gray levels to be supplied to the video imager.</p> |
