PROBLEM TO BE SOLVED: To easily obtain respiratory function indices such as a residual capacity, a functional residual capacity, total lung capacity, and a residual ratio.SOLUTION: A control unit 31 in a radiation image analysis system 100, calculates the area of the lung field from a chest image obtained by radiation imaging of the chest from one direction, and estimates the residual capacity, the functional residual capacity, the total lung capacity, or the residual ratio of the lung field on the basis of the calculated area of the lung field.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2020,JPO&INPIT【課題】残気量、機能的残気量、全肺気量、残気率等の呼吸機能指標を簡便に取得できるようにする。【解決手段】放射線画像解析システム１００の制御部３１によれば、一方向から胸部を放射線撮影することにより得られた胸部画像から肺野の面積を算出し、算出した肺野の面積に基づいて、肺野の残気量、機能的残気量、全肺気量、又は残気率を推定する。【選択図】図３
