[A study of image processing in CR mammography; gradation processing].
CR image is made by several kinds of image processing. Gradation processing is most important to make images among them and its type can be decided by the kinds of x-ray examinations. 1.2 G gradation processing is generally recommended for CR-mammography by the CR maker, but it has not been fully studied that whether 1.2G was the ideal one or not to image masses and/or calcifications. So, we compared the image obtained by 1.2G gradation processing with one by 1.0 d gradation processing that we made about imaging sensitivity of them in 18 cases with breast cancer. 15 out of 18 cases had good mass images and all of 6 cases showed good calcified images in the latter condition due to its high declination ( = gamma). So, we have concluded that 1.0 d gradation processing was better than 1.2G in CR-mammography.