Skip to main content
. 2022 Jun 29;12:898771. doi: 10.3389/fonc.2022.898771

Figure 3.

Figure 3

Illustration of motion hysteresis of a posterior peripheral tumor (patient 2, with 20 breathing cycles in 40 s) during mid-inhalation (A) and mid-exhalation (B) with a similar diaphragm displacement at the zero-gantry angle (BEV = 0°). The isocenter (red cross) position is shown inside the in-plane tumor BEV contour (orange) and the projected volumetric tumor contour (white). Both the in-plane and projected tumor contour shapes and the centers of mass (COMs) are different between inhalation and exhalation. By selectively using either the inhalation or exhalation TR-4DMRI library based on the motion direction, the respiratory hysteresis effect is compensated.