Designing and validating a PVA liver phantom with respiratory motion for needle-based interventions

Purpose: The purpose is to design and validate an anthropomorphic polyvinyl alcohol (PVA) liver phantom with respiratory motion to simulate needle-based interventions. Such a system can, for example, be used as a validation tool for novel needles. Methods: Image segmentations of CT scans of four patients during inspiration and expiration were...

A variable stiffness mechanism for steerable percutaneous instruments: Integration in a needle

Needles are advanced tools commonly used in minimally invasive medical procedures. The accurate manoeuvrability of flexible needles through soft tissues is strongly determined by variations in tissue stiffness, which affects the needle-tissue interaction and thus causes needle deflection. This work presents a variable stiffness mechanism for...