In vitro non-rigid life-size model of aortic arch aneurysm for endovascular prosthesis assessment

Purpose: It is essential to evaluate new stent designs before in vivo testing. The purpose of this study was to develop and validate a controlled and reproducible patient-derived process to produce a life-size in vitro model of aortic arch aneurysm for endovascular procedure simulation. Methods: A three-dimensional magnetic resonance angiography (3D MRA) image derived from a 60-year-old patient with aortic arch aneurysm was segmented using a home-made software package which allows one-click automatic segmentation of the aorta, meshing, and conversion to standard tessellation language (STL) format. A rapid prototyping technique established a stereolithographic model to produce a replica of the whole aorta, including the arch aneurysm and supra-aortic arteries. Results: The final model was made by pouring silicone rubber to obtain a sturdy, life-size, soft, transparent, plastic cast, accurately reproducing both the internal and external anatomy of the aortic aneurysm. This model was used under perfusion by an extracorporeal circulation pump, to test ex vivo stent deployment. Conclusion: The combination of easy segmentation and conversion to the STL format with industrial stereolithography techniques enabled a realistic silicon vascular phantom to be created for endovascular procedure simulation, image modality calibration, and new stent design.