Figure 2.

Example image of continuous airway measurement using the “4D Airways Analysis” software.

Notes: The corresponding measurement points in all 14 frames are shown at the bottom. On this image, a measurement point is set in the right main bronchus in the dependent lung field. A measured Ai of frame No. 8 (blue arrow) is shown in the center square (surrounded by a orange rectangle). Continuous changes in Ai are shown in the upper right square (blue dashed oval).

Abbreviation: Ai, luminal area.