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A monkey phantom is of significant value for electromagnetic radiation (EMR) dosimetry simulations. Furthermore, phantoms in various postures are needed because living beings are exposed to EMR in various postures during their daily routine. In this study, we attempted to produce monkey phantoms based on three daily postures of a rhesus monkey. From our Visible Monkey project, we selected surface models with 177 monkey structures. In the surface models, 52 virtual joints were created to allow for changes from the anatomical position to quadrupedal and sitting positions using commercial software. The surface models of the three positions were converted into monkey voxel phantoms. These phantoms were arranged in three positions, and the number of voxels and mass of each structure were analyzed. The phantoms in anatomical, quadrupedal, and sitting positions have a total of 5,054,022, 5,174,453, and 4,803,886 voxels, respectively. The mass of 177 structures in three positions were also calculated based on the number of voxels. By comparing the monkey phantom with the phantom of a female human, we confirmed thicker skin, less fat, heavier muscle, and a lighter skeleton in monkeys than those in humans. Through posture-transformed monkey phantoms, more precise EMR simulations could be possible. The ultimate purpose of this study is to determine the effects of EMR on humans. For this purpose, we will create posture-transformed human phantoms in a following study using the techniques employed herein and the human phantoms from our previous study.

When performing deep brain stimulation (DBS) of the subthalamic nucleus, practitioners should interpret the magnetic resonance images (MRI) correctly so they can place the DBS electrode accurately at the target without damaging the other structures. The aim of this study is to provide a real color volume model of a cadaver head that would help medical students and practitioners to better understand the sectional anatomy of DBS surgery. Sectioned images of a cadaver head were reconstructed into a real color volume model with a voxel size of 0.5 mm × 0.5 mm × 0.5 mm. According to preoperative MRIs and postoperative computed tomographys (CT) of 31 patients, a virtual DBS electrode was rendered on the volume model of a cadaver. The volume model was sectioned at the classical and oblique planes to produce real color images. In addition, segmented images of a cadaver head were formed into volume models. On the classical and oblique planes, the anatomical structures around the course of the DBS electrode were identified. The entry point, waypoint, target point, and nearby structures where the DBS electrode could be misplaced were also elucidated. The oblique planes could be understood concretely by comparing the volume model of the sectioned images with that of the segmented images. The real color and high resolution of the volume model enabled observations of minute structures even on the oblique planes. The volume models can be downloaded by users to be correlated with other patients’ data for grasping the anatomical orientation.