Patient positioned on a phase II prototype iteration and ready for CT-scanning.
Close-up of the latest prototype iteration.
Phase III prototype iteration positioned on the treatment machine.
Collection of sketches throughout the project.
A breastboard is a device used for radiotherapy of breast cancer. Currently available devices have several limitations and are very uncomfortable. This new design ensures better comfort, patient positioning and beam access, which improves medical performance.
Prone radiotherapy allows decreasing skin toxicity, lowers the risk of lung cancer induction and cardiac damage compared to supine treatment. The currently available prone breast boards are suited for breast irradiation but not for lymph node irradiation because device parts which support the patient restricts favourable beam paths. Seeing this project, I had a strong interest of designing something that could help women with breast cancer. Improving comfort, helping people, making the treatment less painful and establishing a treatment solution with better prognosis and medical results were the biggest design challenges that motivated me.
Prone radiotherapy allows decreasing acute toxicity cosmetic changes and lowers the risk of lung cancer induction and cardiac damage compared to supine treatment. Some commercially available breast boards may be suited for breast and lymph node irradiation, But the devices have several limitations: restricted beam access range for breast and lymph nodes because the treatment couch components and patient position are in the entrance trajectories of favourable beams paths, reduced precision, pain and discomfort. The new device and prone crawl position (patient positioned with the arm at the treated side alongside the body and the arm at the contralateral side above the head resembling a phase of crawl swimming), results in a stable, natural and comfortable patient position. With this device, we are able to treat both breast and lymph nodes in prone position, with improved precision, better dose distribution and sparing of vital organs such as heart and lungs.
Phase I: Basic parameters of the device were determined to obtain the new crawl position. Low-Fi prototypes were produced with inferior materials and basic skills. Volunteer user comfort tests were executed on a small scale. CT-scanned cadavers were used for beam access optimisation. Phase II: More advanced prototypes were produced with integration of previous adjustments. Derived from phase I, a mould was produced for resin infusion moulding of a fibreglass structure. Prototypes were modular constructed and each part could be adjusted and indexed. Instead of developing a new prototype for each iteration, specific parts were redesigned, tested and integrated. In this phase, the use of more durable materials and advanced prototyping techniques were applied since they needed to be functional, accurate and tested in real environment. A small comparative study was performed comparing the prototype with the standard supine breast board at our centre. Phase III: Based on phase II prototype, a CAD-model was derived and optimised. PU-Moulds were CNC-milled for production of high fidelity, fibreglass prototypes with durable and structural materials. Small iterations were performed and sub-parts were improved. 4 prototypes were produced and used for a clinical trial (n=40 patients).
With the new prone crawl patient position and support device, we are able to treat both whole breast irradiation and lymph nodes in prone crawl position. Until now, no other known device was able to do this. Furthermore, by integrating every stakeholder early in the design process, we improved both patient comfort and medical performance. The medical results were improved for: set-up precision, better sparing of vital organs such as heart, lungs, thyroid, contralateral breast; more homogeneous dose distribution to the to be treated area. The device enables us to position patients by means of a floor laser system, which improves patient set-up accuracy.
During the next phase, we want to develop a small series of fully working prototypes, which can be used for a big clinical trial involving 3 hospitals. Our future plans are to redesign the prototype and support structure to make it lighter and stiffer (weight reduction for handling and accuracy improvements for treatment). Additionally, we want to make it MRI compatible, so no ferro metals will be allowed in the design. Finally, we want to upgrade the head support module with the integration of a non-invasive ventilation module, which improves treatment results.
I received the faculty's 2015 Best master thesis award. - I received an Emmanuel van der Schueren research fund (kom op tegen Kanker- Belgian NGO for cancer treatment, care, and research). - I received a Best Poster Award (15th research symposium, from Faculty of Engineering and Architecture).