A Bio-Inspired Active Prostate Phantom for Adaptive Interventions

Abstract

In this paper, a novel concept for a phantom of the prostate is introduced. To study and improve automated, robotized medical interventions, reliable phantoms are essential. During brachytherapy and biopsy, the prostate will undergo displacements and changes in orientation due to the needle insertion. Therefore, there is a shift in the target regions for radioactive seed deposition or biopsy acquisition. These shifts need to be taken into account for precise dosimetry. Furthermore, the organ can undergo deformations due to edemas causing further spatial changes in the target structure. Therefore, in this paper, we propose a bio-inspired phantom (BIP) for the prostate that is equipped with sensors and coupled with a numerical simulation for estimating deformations due to external forces. There is also a cavity within the phantom where pressure can be applied to simulate prostate growth due to inflammation. The phantom has been conceived to be MRI-safe. It can thus be deployed for the in-bore study of automated brachytherapy and biopsy. In our evaluation, we verify that changes in position of the phantom target can be correctly estimated and that these motions are plausible from a clinical point of view.