@article{oai:kanazawa-u.repo.nii.ac.jp:00014736, author = {Tanaka, Rie and Sanada, Shigeru and Fujimura, Masaki and Yasui, Masahide and Tsuji, Shiro and Hayashi, Norio and Nanbu, Yuko and Matsui, Osamu and 田中, 利恵 and 真田, 茂 and 藤村, 政樹 and 安井, 正英 and 辻, 志郎 and 林, 則夫 and 南部, 裕子 and 松井, 修}, issue = {6}, journal = {Japanese journal of Radiological Technology = 日本放射線技術學會誌 / Nippon Hoshasen Gijutsu Gakkai zasshi}, month = {Jun}, note = {Pulmonary ventilation and circulation dynamics are reflected on dynamic chest radiographs as changes in X-ray translucency,i.e., pixel values. The present study was performed to develop a pulmonary functional evaluation method based on the changes in pixel value, and to investigate the clinical usefulness of our method. Sequential chest radiographs of 20 subjects (abnormal,n=12; normal,n=8) during respiration were obtained with a dynamic flat-panel detector (FPD) system. The average pixel value in each local area was measured tracking the same area. To facilitate visual evaluation, the results were mapped on the original image using a grayscale in which small changes were shown in black and large changes were shown in white. In our clinical evaluation in comparison with a pulmonary scintigraphy, pulmonary ventilation disorder was indicated as a reduction of changes in pixel values. In many patients, there was a correlation between our result and a pulmonary scintigraphy (0.7