SU‐FF‐T‐162: Development of a Patient‐Specific Lung Phantom Using 3D Imaging and Rapid Prototyping

Abstract

Purpose: Physical human phantoms have been widely used in verification of external radiotherapy treatment plans, study of exposures outside of the target regions, and calibration of whole‐body counter for nuclear medicine procedures and for radiation safety bioassays. Existing phantoms are mostly crude in anatomical representations, although realistic 3D images of patients are available. This paper presents a method of fabricating a physical phantom of the lung using patient‐specific medical images and computer aided design (CAD) and manufacturing (CAM). Methods: Medical images have been used to construct the VIP‐Man model from Visible Human images. The voxelized data from the lung of VIP‐Man were translated into 3D polygon mesh models. The models were then corrected and scaled to the actual size of the organ. A 3D rapid prototyping machine (i.e., a 3D printer) was used to develop a physical mold of 3D polygon mesh lung. The mold was filled with lung tissue‐equivalent foam, which matched the density and effective atomic number of the lung tissue. Results: Using the methods described above the lung of the VIP‐Man model in STL format was used to fabricate an identical 3D tissue‐equivalent phantom. Conclusions: A method has been developed to rapidly prototype physical lung phantoms using CAD and CAM capabilities. Currently, there is no method that automates this complicated process of creating 3D organ phantoms. A major research effort in this task is to develop an integrated software method that will streamline image processing and 3D printing.