A Systematic Review on 3D-Printed Imaging and Dosimetry Phantoms in Radiation Therapy

Abstract

Introduction: Additive manufacturing or 3-dimensional printing has become a widespread technology with many applications in medicine. We have conducted a systematic review of its application in radiation oncology with a particular emphasis on the creation of phantoms for image quality assessment and radiation dosimetry. Traditionally used phantoms for quality assurance in radiotherapy are often constraint by simplified geometry and homogenous nature to perform imaging analysis or pretreatment dosimetric verification. Such phantoms are limited due to their ability in only representing the average human body, not only in proportion and radiation properties but also do not accommodate pathological features. These limiting factors restrict the patient-specific quality assurance process to verify image-guided positioning accuracy and/or dose accuracy in “water-like” condition. Methods and Results: English speaking manuscripts published since 2008 were searched in 5 databases (Google Scholar, Scopus, PubMed, IEEE Xplore, and Web of Science). A significant increase in publications over the 10 years was observed with imaging and dosimetry phantoms about the same total number (52 vs 50). Key features of additive manufacturing are the customization with creation of realistic pathology as well as the ability to vary density and as such contrast. Commonly used printing materials, such as polylactic acid, acrylonitrile butadiene styrene, high-impact polystyrene and many more, are utilized to achieve a wide range of achievable X-ray attenuation values from −1000 HU to 500 HU and higher. Not surprisingly, multimaterial printing using the polymer jetting technology is emerging as an important printing process with its ability to create heterogeneous phantoms for dosimetry in radiotherapy. Conclusion: Given the flexibility and increasing availability and low cost of additive manufacturing, it can be expected that its applications for radiation medicine will continue to increase.

Assessing the Radiological Density and Accuracy of Mandible Polymer Anatomical Structures Manufactured Using 3D Printing Technologies

“…However, there have been no studies carried out on such a wide range of polymer materials. Furthermore, 3D printing is becoming increasingly available and offers new opportunities to tailor phantoms for specific clinical and research purposes, including radiotherapy [63][64][65]. It is particularly important to initiate research on developing tomography phantoms of the mandible area to more precisely diagnose tumorous lesions.…”

“…In the process of evaluating geometric errors, optical systems are used [41,42,61]. There are also publications that take into account the use of tomographic systems in the process of assessing the accuracy [62] and radiological density of 3D printed phantoms used in medical diagnostics [63][64][65]. In this case, the most frequently analyzed polymer materials are acrylonitrile butadiene styrene (ABS) [64,66,67], polylactic acid (PLA) [66][67][68][69], and acrylic resins [65,70].…”

Technical Note: Accurate replication of soft and bone tissues with 3D printing

“…Three‐dimensional printing technologies have been extensively used for the replication of the average HU of soft tissue human organs 9 . However, an important aspect for realistic patient‐specific phantoms is also the replication of bone tissue, which is important if lower energy radiation beams are used.…”

Three-Dimensional Printed Silicone Bite Blocks for Radiotherapy of Head and Neck Cancer—A Preliminary Study

“…There is a growing interest in the application of three-dimensional (3D) printing to the RT process. The majority of studies focus on the creation of boluses [8,9], masks [10,11], and phantoms for quality assurance [12,13]. Their clinical use in HNC RT is still under investigation.…”