State-of-the art 3D printing relies on the optimization of imaging. Radiologists who are involved in 3D-printing research can help accomplish this. They can also perform the post-processing required for 3D printing, accurately and efficiently.
Centralization of 3D printing, data collection, and quality control in the radiology department provides many research opportunities related to 3D printing.
Current opportunities for radiology engagement:
(1) Optimizing image acquisition.
Optimization of CT and MR image acquisition is key for translating DICOM data into high-quality 3D renderings suitable for printing, and the creation of the actual models and constructs. Research in optimizing image acquisition and data processing could include defining if CT or MR produces better anatomic models for a given disease process. With CT, this could include determining if high-resolution multiplanar reconstructions are necessary for model creation. With MR, sequences that best demonstrate a given pathology can be an area of research.
MR-based 3D-printed models should be an active research area in addition to CT based printing, with design of new imaging sequences and techniques that can maximize the diagnostic utility of 3D models derived from magnetic resonance imaging data. Additionally, additive manufacturing from 3D acquired sonographic data may have a role, particularly in prenatal ultrasound.
(2) Optimizing segmentation and post-processing.
Segmentation software plays an important role in 3D printing; however, it is often limited given the technology that radiology departments currently use in the clinical setting. Radiologists, in conjunction with engineering specialists, should play a major role in the development of appropriate software with advanced capabilities for this purpose, as well as harness strengths of a given modality through creation of specific protocols. Development of such software will require FDA approval for clinical use.
(3) Optimizing 3D printing workflow in the context of standard image acquisition and interpretation.
3D printing will flourish within radiology only if it can be easily integrated into a radiologist’s daily routine. Automated sectioning and transitioning to 3D printing-compatible files would be needed to optimize the workflow of a medical 3D printing laboratory led by radiologists.
(4) 3D printing for tissue engineering.
There have been exciting advances in tissue engineering outside of 3D printing, such as bladders and urethras grown in laboratories and implanted in patients. At the time of writing, 3D-printed organs or tissues have not been used in humans. However, studies have demonstrated human derived tissue implanted in mice and rats in the form of ear cartilage and calvarial bone 3D-printed constructs. Advances in 3D-printing technology could potentially revolutionize organ transplantation. In nearly all areas of transplant, there are shortages of deceased donors, few living donors, and many patients on transplant waiting lists. For example, given the increasing need for liver transplantation, the relative lack of cadaveric donors, and high morbidity of healthy living donors with lobectomy, preoperative 3D-printed models can be of great benefit to patients. Although feats such as 3D printing of human kidney tissue have been achieved, replicating the entire architecture of a 3D printed organ is more challenging and needs to be attained before this technology is ready for use in humans.
(5) Introducing training programs for residents and radiologists in the steps of 3D printing. This will create a larger pool of radiologists involved in the process, improve accuracy, and assist in the continuity and sustainability of this technology within radiology departments.
(6) Demonstrating value in patient care, particularly in preoperative planning.
For 3D printing to become reimbursable, further demonstration of its value will be needed. Although this has already been demonstrated in few prior studies, additional studies are needed.
(7) Standardizing terminology related to 3D printing.
For 3D printing to become a reimbursable service provided by radiologists, it is prudent to develop a standardized lexicon on naming models, the process of printing itself, and other related factors.
Chepelev et al. conducted a literature search to standardize terminology related to 3D printing. They concluded that “3D printing,” “additive manufacturing,” and “rapid prototyping” are three nearly synonymous terms used to describe the concept of 3D printing. They found that by 2015, “3D printing” was the most frequent descriptor (>60%) and they advocate its use over the other two terms.
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