Elaboration and development of a realistic 3D printed model for training in ultrasound-guided placement of peripheral central venous catheter in children.

Background: Simulation for training is becoming a trend topic worldwide, even if its applications are commonly limited to adulthood. Ultrasound-guided procedures require practice and experience-especially in the pediatric field, where the small size of the involved anatomical structures poses major problems. In this context, a realistic 3D printed pediatric phantom for training of the ultrasound-guided placement of peripheral central venous catheters in children was developed.

Materials and methods: Starting from Computed Tomography scans of an 8 years-old girl, her left arm was virtually reconstructed-including bones, arteries, and veins-through a semi-automatic segmentation process. According to preliminary results, the most suitable 3D printing technologies to reproduce the different anatomical structures of interest were selected, considering both direct and indirect 3D printing techniques. Experienced operators were asked to evaluate the efficacy of the final model through a dedicated questionnaire.

Results: Vessels produced through indirect 3D printing latex dipping technique exhibited the best echogenicity, thickness, and mechanical properties to mimic real children's venous vessels, while arteries-not treated and/or punctured during the procedure-were directly 3D printed through Material Jetting technology. An external mold-mimicking the arm skin-was 3D printed and a silicone-based mixture was poured to reproduce real patient's soft tissues. Twenty expert specialists were asked to perform the final model's validation. The phantom was rated as highly realistic in terms of morphology and functionality for the overall simulation, especially for what concerns vessels and soft tissues' response to puncturing. On the other hand, the involved structures' US appearance showed the lower score.

Conclusions: The present work shows the feasibility of a patient-specific 3D printed phantom for simulation and training in pediatric ultrasound-guided procedures.