Analog-imaging technique

We evaluated important factors regarding imaging technique - 1) selecting of the collimator, 2) setting of the energy peak and window width, 3) determination of the count, 4) suitable image size and 5) suitable image density. Detectability was compared with visual response using IAEA liver phantom. On the phantom study using sup(99m)Tc, we obtained the following results: count density; 2000-3000 c/cm2 on useful count density, image size; 6-9 format on 8 x 10 inch film on useful image size, image density; 0.5-1.5 (cold lesion) and 0.5-0.9 (hot lesion) on useful image density. It was the collimator and count that influenced the variance of the image quality more than the other factors regarding imaging technique. (author)