Simulation of Complex Skull Base Tumor Removal in a Cost-Effective Perfused Cadaveric Model: Our Experience

Background: Complex skull base tumor resection poses formidable challenges due to intricate neuroanatomy and critical neurovascular structures. Traditional training methods require steep and long learning curves, with progressive hands-on experience to be weighted for case complexity, timing of surgery, team expertise, and patients’ condition. Although standardized fellowship programs represent the gold standard for training in such complex scenarios, continuity in hands-on practice remains an issue. Some models are available to simulate such conditions; however, previously proposed cadaveric models require highly expensive instrumentations, and simulation models are only partially realistic. We developed an innovative in-house simulation model for cadaveric anatomical courses and technical training, specifically designed to replicate complex skull base tumor resection, enabling participants to practice several cranial approaches and tumor excisions in a controlled, high-fidelity environment.

Methods: An in-house pumping prototype was employed with five independently modulated pumps (two each for carotid arteries and internal jugular veins and one for cerebrospinal fluid injection through a ventriculostomy). A console allows precise control of each pump's function and intensity, simulating physiological conditions and variability. Colored condensed saline simulates arterial and venous flow, enhancing visual cues during procedures. The model utilizes formalin-flushed, uninjected cadaveric specimens. Two mini craniotomies are carried out to inject tumor substitutes in the selected intracranial districts (ministerial and mini-retro sigmoid) through narrow dural incisions. Polyurethane foam is injected to simulate intra- or extradural tumors. The foam’s expansion creates a solid mesh, displacing brain and brainstem structures while encasing neurovascular structures, presenting an authentic tumor resection scenario.

Results: Twenty participants engaged in multiple simulation sessions, including neurosurgery and otolaryngology residents and attendings. A combined petrosal, a retrosigmoid, a pterional, a midline frontal trans-sinus, a lateral transorbital, and a binostril endoscopic endonasal approaches were carried out according to tumor injection to simulate the most relevant surgical cases. Tumor resection was performed with microsurgical instruments, microdebriders, and ultrasonic aspirators. Recording of simulation sessions allowed off-line evaluation of the performance of residents and attendings. Participant feedback was collected via a questionnaire. The model demonstrated exceptional feasibility with minimal reported malfunctions. Participants emphasized the simulation’s realism, particularly praising the visual and tactile fidelity. They noted the challenging nature of working within small surgical corridors, reduced maneuverability, and the realistic tumor texture provided by the polyurethane foam. The foam's adherence to dura and arachnoid membranes necessitated intricate dissection skills to preserve specimen integrity, closely mimicking real surgical scenarios. The perfusion system successfully simulated blood flow, with realistic bleeding occurring during suboptimal vessel manipulation and injury. This complication required vascular control with clips, widening the simulation scope and forcing operators to manage real-case complications and adapt resection strategies.

Conclusion: The proposed cost-effective model can replicate intricate surgical challenges, including working in confined spaces, managing adherent tumors, and dealing with vascular complications, offering invaluable hands-on experience beyond traditional methods. Positive participant feedback confirmed the model’s potential for neurosurgical and ENT training programs, enhancing the surgical learning experience and providing a new tool for constant skill assessment and refinement in skull base surgery.

Publication History

Article published online:
07 February 2025