Constructing Customized Multimodal Phantoms Through 3D Printing: A Preliminary Evaluation

Jianfeng Qiu,Longchun Xu,Zhengmei Li,Jyh-Cheng Chen,Brandon A Dyer,Haozhao Zhang,Minghui Li,Huihui Zhao,Liting Shi,Yi Rong,Kun Hou,Tiao Chen,Fuquan Zhang,Yong Sun

doi:10.3389/fphy.2021.605630

Abstract

Purpose: To develop a method for constructing customizable, multimodal quality control (QC) imaging phantoms based on 3D printing technology.Materials and Methods: Four phantoms were designed and constructed through 3D printing technology using three unique printing materials. Physical parameters of the 3D printed materials were evaluated, including density, shore hardness, porosity, deformation temperature, computed tomography (CT) number, absorption coefficient, and printing accuracy. Imaging performance of the phantoms was studied using MRI, CT, PET/MR, and PET/CT, and compared with conventional/commercial phantoms. Imaging assessments included high contrast resolution, low contrast resolution, uniformity, deformation, SNR, slice accuracy/slice thickness, location accuracy/laser alignment, CT number, relaxation time, and registration.Results: All three printing materials have a shore hardness of 90. The physical densities of these materials are 1.15 g/cm3, 0.76 g/cm3, and 1.27 g/cm3, respectively. The porosities are 9.09, 6.81, and 18.56%, respectively. The threshold temperature of deformation for the three materials is &gt;105°C, which is higher than that of PMMA and silica gel. Imaging scans of the constructed phantoms for single modality scanners (MRI and CT) and dual-modality scanners (PET/MRI and PET/CT) were compared with those of the commercial phantoms. The standard deviation of the HU value uniformity test was &lt;3 HU for CT scans.Conclusion: 3D printed medical imaging phantoms allow for rapid, customized phantom fabrication for clinical situations across single and dual modality imaging platforms. Further imaging parameter analysis is underway to provide more quantitative evaluation of the proposed phantoms.

Highlights

Medical imaging quality assurance (QA) and quality control (QC) is facilitated by well-designed physical phantoms [1,2,3,4]
Most imaging phantoms are designed for a single imaging modality, such as those accredited by the American College of Radiology (ACR) and American Association of Physicists in Medicine (AAPM) for computed tomography (CT), positron emission tomography (PET), or magnetic resonance imaging (MRI) [5, 6]
The decreasing cost of 3D printing technologies and material development has resulted in the ability to fabricate customdesigned, 3D printed multi-modality imaging phantom as a viable alternative

Summary

Introduction

Medical imaging quality assurance (QA) and quality control (QC) is facilitated by well-designed physical phantoms [1,2,3,4]. A combination of materials can be used simultaneously for constructing a customized object using 3D modeling software. Such applications have been extensively explored for medical devices in the health industry thanks to the ease of rapid device prototyping and broad geometric printing flexibility [8,9,10]. 3D printing technology has been used for constructing phantoms for simulating human/animal anatomies [11,12,13,14], image quality evaluation and assurance [4, 15,16,17,18,19], radiation dose measurement, and other applications [20,21,22,23,24,25,26]

Methods

Results

Conclusion