Fig. 2
A 58-year-old male healthy volunteer with FEV1% 73.3 and %FEV1 92.4, included in the normal group. VF-DXR images: (a) tidal inspiratory, (b) tidal expiratory, (c) forced inspiratory, and (d) forced expiratory phases. Blue rectangles in Fig. 1c represent ROIs in both lungs. The graph (e) shows the temporal change between LMV in the right lung and the number of frames. The frame rate is set to 5 frames/s (Video 1, Supplemental material). FEV1% Forced expiratory volume percent in one second divided by forced vital capacity, %FEV1 Percent predicted forced expiratory volume in one second, LMV Lung motion velocity, VF-DXR Vector-field dynamic x-ray, ROI Region of interest