[Fabrication and verification of three-dimensional prototyped models of nasal cavities and paranasal sinuses]

Objective: To make three-dimensional prototyped models of nasal cavities and paranasal sinuses for endoscopic skills training and teaching and to verify and evaluate the fidelity of the models. Methods: Imaging data of a patient with nasal septum deviation was selected for prototyping the nasal cavities model, and the imaging data of a patient with chronic rhinosinusitis who underwent the endoscopic sinus surgery 4 months ago was selected for the paranasal sinuses model. Both patients came from the Department of Rhinology, the First Affiliated Hospital of Zhengzhou University. The models were printed by the desktop-level printer based on the fused deposition modeling (FDM). The evaluations of anatomical structures and prespecified tasks on the simulators were completed by 5 residents and 5 experts of Rhinology.The models were evaluated by survey ratings based on a 5-point Likert scale. The average time to complete each task was calculated.Mann-Whitney nonparametric test was used to assess the differences between experts and residents groups. The statistical significance level was set at P<0.05. Results: All the components of the two models were prototyped in 24 h. For the nasal cavities model, the scores of each anatomical structure were more than 4.0. As to the paranasal sinuses model, except for the frontal sinus (3.6), the scores of each anatomical structure were more than 4.0. All the participants who performed the prespecified tasks evaluated the models well (>4.0). With the nasal cavity simulator, the experts completed the tasks (nasal cavity and nasopharyngeal endoscopy, removal of nasal foreign body, nasal packing, pledget insertion), and the other tasks (the nasal cavity and nasopharyngeal endoscopy, identification of ostiums of paranasal sinuses, maxillary sinus debridement with 70° nasal endoscopy) were completed with paranasal sinus model. The average time to complete each task by experts group and residents group (M (P(25), P(75))) were 10.3 (10.0, 10.7) s vs 17.1 (14.6, 20.7) s, 2.1 (2.0, 2.2) s vs 3.4 (2.6, 4.7) s, 30.1 (27.8, 32.8) s vs 59.2 (52.0, 65.4) s, 54.8 (50.1, 63.2) s vs 92.2 (79.3, 106.9) s, 9.3 (8.7, 9.9) s vs 14.5 (13.3, 14.9) s, 20.1 (19.3, 21.2) s vs 41.9 (35.5, 45.1) s, 31.1 (28.8, 35.2) s vs 52.8 (47.7, 56.3) s, respectively, and the average time to complete each task was shorter for the experts group than for the residents (U value was 0, 1.000, 0, 0, 0, 0, 0, respectively, all P<0.05). Conclusion: The models of nasal cavities and paranasal sinuses made by our desktop-level FDM 3D-printer are useful for endoscopic training skills.