Objective Validation of Endoscopic Sinus Surgery Performance on a 3D-Printed Simulator Using OSATS Score and Radiological Assessment

Simulation-based training is increasingly used to support skill acquisition in endoscopic sinus surgery (ESS), although many existing simulators lack objective methods for performance evaluation. This study aimed to assess the face and construct validity of a patient-specific, multi-material 3D-printed sinonasal simulator for ESS using both structured technical scoring and postoperative radiological analysis. Fifteen surgeons with different levels of experience (novices, intermediates, and experts; n = 5 per group) performed a standardized sequence of ESS procedures on identical 3D-printed models, including dacryocystorhinostomy, uncinectomy, maxillary antrostomy, anterior and posterior ethmoidectomy, sphenoidotomy, and frontal sinusotomy (DRAF I). Surgical performance was evaluated on video recordings using a modified Objective Structured Assessment of Technical Skills (OSATS) score. After simulation, each model underwent computed tomography (CT) scanning and a dedicated radiological checklist was applied to assess the adequacy of surgical steps, dimensional parameters of enlarged sinus ostia, and potential procedural complications. Mean OSATS scores differed significantly among expertise levels, with experts achieving higher scores (48.0 ± 1.9) than intermediates (39.4 ± 3.4) and novices (28.4 ± 3.8) (p < 0.01). CT analysis showed a significantly greater extent of ethmoidal cell removal in experts compared with novices (87.5% vs. 57.5%, p = 0.02) and a larger latero-lateral diameter of the frontoethmoidal recess compared with intermediates (p = 0.04). Questionnaire results indicated high perceived educational value, particularly among novices, despite some limitations in haptic realism. While the simulator appears to be a promising tool for ESS training, further studies are required to validate its effectiveness in improving surgical performance.