Fig. 1

Two major procedures to obtain bone marrow (BM) positron emission tomography (PET). First: “BM computed tomography (CT)" was obtained. Whole spine and pelvic bones, including the BM, were automatically extracted from whole-body CT images using a bone-extraction algorithm implemented in the analyzer for automatic bone segmentation based on multi-task three-dimensional fully convolutional networks (3D-FCN) [19]. A multi-task 3D-FCN for organ segmentation has surpassed the two-dimensional FCN approach [20] by using data from multiple segmentation datasets and showed improvement over the single-task 3D-FCN approach (a). The contour lines were subsequently set to 2 pixels inside the first line, which were able to extract the BM and remove as much cortical bone as possible (b). Second: overlay bone marrow CT on whole-body PET (c), and obtain “bone marrow PET” masked with bone marrow CT (d)