Modular 3D-printed liver tumour phantom for modelling embolization procedures

Angiographic evaluation is important in embolization procedures to ensure a proper amount of embolic material is delivered to target vessels. Simulation of image-guided interventions with phantoms enables scientists and residents to better understand techniques to avoid procedure-related complications. In this study, a phantom with an exchangeable, single-use tumour model was designed and fabricated using 3D-printing in polylactic acid plastic. A 1.5 cm sphere made of gyroids with varying pore sizes was used in place of tubular structures to simulate tumour microvasculature and thereby provide restrictive passages that trap embolic material. Hemodynamic blood properties were replicated using a pulsatile flow pump containing a glycerol-water mixture and flow resistance was mimicked by adding tubing to each outlet vessel. Tissue-mimicking material was introduced around the phantom to provide radiographic path equalization. The modular phantom was used to mimic fluoroscopically guided embolization procedures in three tumour models, culminating in reflux observed in the feeding artery. Angiography revealed a tumour blush created by the gyroid patterns. Embolization of the tumour model proceeded gradually with contrast agent accumulating in the tumour over time where reflux developed after injecting 5.4 +/- 2.4 mL of a microsphere/contrast mixture. The pulsatility of the blood-mimicking fluid was clearly seen when contrast agent was injected. Digital subtraction angiography after embolization revealed complete stasis of antegrade flow through the tumour model. The 3D printed modular phantom design facilitates the reusability of the liver model following embolization, allowing for a more efficient and versatile tool for embolization training and research applications.