Usefulness of a 3 Dimensional-printed Head Model with Two-layered Dura and Cerebellar Tentorium for Transpetrosal Approach Training

The combined transpetrosal approach provides effective exposure to the petroclival region and ventral brainstem, although its technical demands necessitate advanced neurosurgical expertise. Proficiency in skull base drilling and meticulous separation of the dual dural layers is crucial. Recently, three-dimensional printing has gained attention as a tool for surgical training. To evaluate its potential in transpetrosal approach education, we developed a three-dimensional head model that reproduces the soft brain tissue, cranial nerves, vasculature, and tumors. A petrotentorial meningioma case was selected, and a corresponding three-dimensional model was generated using computed tomography and magnetic resonance imaging data. The skull base was printed using a three-dimensional printer. Liquid rubber-coated kitchen paper simulated the dura mater, wool yarn represented blood vessels, and rubber bands were used for cranial nerves. Ultra-soft polyurethane resin was employed to replicate the brain, brainstem, cerebellum, and tumor. Neurosurgeons practiced the combined transpetrosal approach on the model and completed a questionnaire evaluating anatomical accuracy and operative usability. Thirteen neurosurgeons participated. No statistically significant differences were found between those with experience in ≥5 combined transpetrosal approach and those with less experience. All participants gave favorable evaluations regarding the model's anatomical accuracy and its value for preoperative planning and surgical training. The model supported essential transpetrosal approach steps, including skull base drilling, dual-layer dural dissection, and tentorial incision, allowing for thorough practice of the combined approach. It offers a practical, realistic training platform that closely resembles actual surgical conditions.