Breakthroughs in Skull Base Laboratory Training and Preoperative Planning: Lateral Thinking and Repurposing Old/Obsolete Imaging CDS

Introduction: Access to cadaveric specimens can be constrained by high costs, limited availability and decay itself. Over the past 5 years, numerous efforts have been undertaken to address these challenges, aiming to augment and refine neurosurgical skills through the utilization of inanimate 3D-printed models.

Objective: Repurposing outdated CT imaging from navigation-ready cadaveric specimens to produce subject-specific 3D-printed skull models. This offers a cost-effective and highly accurate platform for training and surgical planning, even after mandatory disposal of specimens due to biohazard regulation protocols.

Methods: Neuronavigation-ready CT scans from 8 cadaveric specimens were processed and converted into STL files (Stereolithography). These were processed by UltiMaker Cura (New York, United States) and used to acquire 3D printed navigation-ready skulls with Ender-3 (Shenzhen Creality 3D Technology Co., Ltd, Shenzhen, China). The method involves conversion of DICOM files obtained from outdated scans of subjects into STL files.

Results: This allows for meticulous representation of bone anatomy, including the clinoid processes, lesser sphenoid wing, optic canal roof, and optic strut, amongst others. These features enhance neurosurgical technical aspects related to specific approaches to the skull base, such as anterior and posterior petrosectomy, drilling of the anterior and posterior clinoid processes, and endoscopic approaches through the nasal cavity, serving as a tool for hands-on experience and training, integrated with real-time navigation. Ability to combine the model and with augmented reality using virtual reality is a plus, with high accuracy for morphometric cranial measurements and volumetry.

Conclusion: These models, incorporating real-time neuronavigation, hold significant potential for both surgical planning and training. Moreover, they have the potential to seamlessly replicate certain subject specific model in series at a low cost-value ratio, even after deterioration. This paradigm offers a realistic simulation environment, enhancing spatial awareness and procedural accuracy, hopefully reducing the learning curve in the use of navigation and neurosurgical drilling technique overall.

Fig. 1 3D print of a model, in which the Pterional approach was performed in Skull Base Laboratory. Highlighted are the areas after completing anterior petrosectomy (Kawase’s Triangle, green), anterior clinoidectomy (Red), and drilling of the lateral wall of the orbit (light blue). Additionally, registry of the anterior clinoid process demonstrates accuracy of the models. Finally at the center of the figure it can be observed the Virtual Reality environment accessible for each specimen.

Fig. 2 Surgical trajectory fixed to the right anterior clinoid process (ACP), with probe positioned on the tip of the contralateral ACP.

Fig. 3 Surgical trajectory fixed to the right anterior clinoid process (ACP), with probe entering through left optic canal and pointing the tip of the left ACP.

Fig. 4 Surgical trajectory fixed to the right anterior clinoid process (ACP), with probe gaining endonasal access to the sphenoidal rostrum.

Publication History

Article published online:
07 February 2025