3D Printed Anthropomorphic Phantoms for Guided Radiotherapy

MRI guided radiotherapy has the potential to transform treatment outcomes in several challenging cancers, including lung and pancreas, through daily treatment adaptation and real time motion tracking. Consideration for patient comfort means that scans must be as short as possible, however it is essential that geometric fidelity be maintained in the images. Phantoms are objects designed to respond in imaging similarly to human tissues and organs, and have an essential role to play in validating new imaging techniques by providing a well-defined "ground truth" to compare against experimental results. However, current generation phantoms are simple geometrical structures which do not adequately capture the nuances of real patient scanning.1

As well as their use in research for improving imaging and radiotherapy techniques, more faithful phantoms will also have an important role to play in medical practice. For example, in multi-centre clinical trials, phantoms moved between centres can calibrate the performance of different scanners and processing pipelines. Phantoms are also used in the clinic for QA of scanner accuracy, which is particularly important in guided radiotherapy treatment (e.g. MR-Linac) because the images are guiding radiation beams directly. Current phantoms are a poor surrogate for patient geometry, hampering the development and clinical adoption of new imaging techniques and treatment protocols.

In this project, we propose to use multi-material 3D printing to produce phantoms with a step-change in fidelity, while also developing multi-material silicone AM techniques with broader relevance in biomedicine.