68-5

34/120

484Figure 3　Diaphragm selection operation screen showing coronal, axial, and sagittal views of the diaphragm. (a) The location of the diaphragm attached to the chest wall. (b) Location of the diaphragm attached to the liver. (c) Location of the diaphragm attached to the heart. (d) Location of the diaphragm without attachment to any surrounding organs.Figure 4　Diaphragm selection operation screen showing a coronal view of the diaphragm (a) before selection and (b) after selection. Diaphragm extraction: The diaphragm was separated from the heart, lungs, liver, and other surrounding tissues and then reconstructed (Figure 3 and Figure 4). Color mapping: Color mapping was performed such that the entire diaphragm was visible (Figure 2b).For each slice, the diaphragm was selected and extracted (Figure 2b). The diaphragm was then reconstructed using the contour trace function (Figure 2c). We performed color mapping to ensure that the entire diaphragm was visible (Figure 2-d), and the volume was measured using the 3D volumetry function (Figure 2e). Each of these steps is detailed below.For diaphragm selection, it was easy to select the diaphragm when there were no surrounding organs (Figure 3d). However, it was difficult to identify the diaphragm when surrounding organs were present, especially at locations in which the diaphragm and liver were attached (Figure 4). The following rules were used to standardize the selective extraction of the diaphragm: (1) The selection was first based on the coronal view and confirmed in the axial and sagittal views after extraction (Figure 3); (2) locations in which the diaphragm was attached to the chest wall and heart were not selected (Figure 3a and 3c); and (3) the zoom function was used more carefully to