In this paper, a brain phantom for evaluating brain stroke localization is proposed. To evaluate brain stroke localization, a phantom imitating three-dimensional (3D) simulation environment is needed. Mold for the proposed phantom was printed by a 3D printer and the interior of the phantom consists of 5 different brain tissue materials. Each of the brain tissue materials has the conductivity and permittivity similar to those of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) standards for a frequency band from 0.5 to 2 GHz.Key Words: Brain, Phantom, Stroke Localization, 3D Printer. Manuscript received August 12, 2016 ; Revised October 12, 2016 ; Accepted October 17, 2016. (ID No. 20160812-026J) Department of Electronics and Computer Engineering, Hanyang University, Seoul, Korea * Corresponding Author: Jaehoon Choi (e-mail: choijh@hanyang.ac.kr) This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ⓒ Copyright The Korean Institute of Electromagnetic Engineering and Science. All Rights Reserved.
LEE et al.: REALISTIC HEAD PHANTOM FOR EVALUATION OF BRAIN STROKE LOCALIZATION METHODS USING 3D PRINTER
255Dimensions for the molds of a phantom (height, 265 mm; sagittal width, 260 mm; coronal width, 197 mm; and thickness of mold, 8-12 mm) are the same as brain CAD data provided by ANSYS HFSS (ver. 14). However, the CAD data could not be applied directly to the phantom molds since the data had holes and overlapping parts. The ANSYS CAD data was modified to enclose each brain tissue and to eliminate overlapped parts. In addition, the oval and nasal cavities were eliminated. The brain model was printed as molds by MakerBot 3D printer whose resolution was 0.1 mm [12]. Fig. 1(a) shows the 3D printer. Even though the real brain consists of a lot of tissues, CAD data of the molds, and (c) photo of the molds. the brain was subdivided into 4 major tissues (spinal cord, cerebellum, white matter, and cerebrospinal fluid) in our head phantom model. The printed molds consist of outer parts and inner molds, including white matter, cerebellum, and spinal cord, as shown in Fig. 1(b) and (c). The outer molds were used as the outer shell of the brain phantom, while the inner molds were used to separate and shape the brain tissue materials, and were extracted after the tissues solidified. The inner molds were used only for shaping and locating the brain tissue materials. Spinal cord, cerebellum, and white matter among the subdivided 4 major brain tissues were embedded with supporters to main the proper locations. The filament used for making the molds is polylactic acid (PLA) and its relative permittivity is about 2.0.
Recipes for the Blood and Brain Tissue MaterialsRecipes for the 4 brain tissue materials and blood material were developed such that the ...