Within the ARCHITECT programme, customised applicator design rules and development tools will be constructed. We hypothesize that customised BT applicators enhance conformity between target volumes and prescribed isodose, and minimize interstitial invasiveness (required number of needles). With smart designs, customised applicators may further improve patient comfort, user friendliness and situation awareness, e.g. by design for visibility in MRI and ultrasound. In addition, image-guided corrections of applicators and needle paths in 4D prints, containing embedded compliant mechanisms, will be assessed. Conformity will be quantified in CT/MRI, using dose planning software and COIN indices, based on scans of applicators positioned in tissue-mimicking phantoms, as well as clinically acquired images. Ultimately, improved conformity will increase local tumour control and cure, and decrease side effects and their impact on quality of life.

For women undergoing gynaecologic brachytherapy, we aim to optimise treatment conformity with 3D printed patient-tailored applicators, including spatially optimized needle source channels for intracavitary and image-guided interstitial use. High conformity accommodates local tumour control and cure, while reducing (long-term) side effects and their impact on quality of life of patients.