Patient-Specific Vascular Anatomy for ECMO Training Model Realized with 3D Printing

Objectives: The implantation of va-ECMO can be challenging especially under cardiac arrest conditions.

In order to be able to train the implantation procedure in complicated cases, a model was built resembling the iliac arteries corresponding to difficult patient anatomy. In this work, we particularly focused on the vasculature anatomy.

Methods: An anonymized data set of a patient CT scan with difficult anatomy for va-ECMO implantation was processed in silico for the manufacturing of a three-dimensional cast bed. The voxels of the DICOM format were transformed into a surface mesh in a stereolithographic format (STL). Later, the mesh was virtually sliced and prepared for additive manufacturing. Afterwards the cast bed was designed with cuts in relevant planes for the insertion of a casting core. The final cast bed was infused with cast-silicon and let harden. Then, the cast bed was carefully removed and the casting core broken and removed from the inside of the silicone model.

Results: The transformation from the DICOM formatted CT scan into the surface-mesh model saved in the stereolithography format was feasible. The design of the cast bed and casting core were the most challenging steps. Especially, the design of the cast core was critical for the later removal after the silicone cast. The silicone vascular structure itself was comparable to the geometry of the CT data. The model is flexible and demonstrated a robust eligibility for ECMO implantation training.

Conclusion: We established a procedural workflow to convert various anatomic vessel dimensions from CT data into personalized silicone models. This technique may open the way for more realistic education of medical trainees to improve their ECMO implantation technique by puncturing a perfused silicon model.