Respiratory motion poses significant challenges in medical imaging procedures involving the liver, such as in biopsies and tumour ablations. The movement of organs caused by breathing can reduce the precision of needle insertions, increasing the risk of tissue trauma and other treatment complications. While existing liver phantoms can simulate respiratory motions, they often lack the realism of specific needle insertion boundaries and the robustness needed for accurate testing and validation, especially in magnetic resonance imaging (MRI) compatible environments.
In this thesis, an anthropomorphic liver phantom setup that replicates Superior-Inferior (SI) and Anterior-Posterior (AP) respiratory movements was developed and validated. The actuation of the phantom is done using MRI-compatible pneumatic origami actuators, chosen for their cost-effectiveness and force actuation capabilities. A soft gelatin liver phantom housed within a 3D-printed ribcage was designed to mimic realistic anatomical constraints. The system operates with an open-loop Arduino control mechanism to recreate human breathing patterns, with the future potential to integrate closed-loop control which could further enhance the accuracy and realism of the movements. The entire setup is modular and built from materials carefully selected for MRI compatibility.
The results demonstrate that the phantom achieves controlled motion in both the SI and AP directions, validating its potential for simulating respiratory motion in a clinical context. The design’s modularity allows for easy maintenance and adaptability for further improvements. This work represents a step toward creating a more realistic and functional liver phantom, thereby contributing to safer and more effective liver procedures.