Capturing 3D patient features for rapid prototyping in radiotherapy prior to simulation

Abstract

When superficial tumors are treated with radiotherapy, bolus may be needed to ensure adequate dose delivery to target tissue. The bolus is typically fabricated at the time of computed tomography (CT) simulation, but in many cases, creating a bolus prior to simulation can be more efficient. Therefore, we devised a workflow that would allow for 3D patient scanning at the initial consultation so that bolus can be fabricated by rapid prototyping before CT simulation. A 3D-printed bolus was fabricated using surface scans of a head phantom that were obtained from a Microsoft Kinect. After processing the scans, a commercially printed 3D bolus was made. To test the feasibility and conformity of the process, masks were made for patients using the above method. 3D-printed bolus created using the rapid scanning technique proved to be the most conformal when compared with bolus made of VPS and SuperFlab. The printed masks also showed that they were formed fitting and comfortable to wear. We present a new workflow that combines current known methods of both rapidly scanning a patient’s surface and the subsequent rapid creation of bolus that then increases bolus conformity, improves comfort and the patient experience, reduces simulation time, and may decrease exposure to radiation.