Pilot Study Evaluating Augmented Reality Craniotomy Guides for Fronto-Orbital Advancement

Objective: Augmented reality (AR) has recently emerged as a potential alternative to 3D-printed technology in craniomaxillofacial surgery. The purpose of this study was to evaluate the feasibility and accuracy of AR craniotomy guides for fronto-orbital advancement (FOA) compared to conventional 3D-printed guides. Design: Retrospective comparative study. Setting: Cleft and craniofacial center at a tertiary children's hospital. Patients: 3D-printed skull models from 9 patients with metopic or coronal craniosynostosis who underwent FOA between January 2022 and November 2023. Interventions: A novel application was developed to project AR craniotomy guides onto 3D-printed skull models. AR guides were compared to conventional 3D-printed guides by utilizing both guidance modalities. The discrepancy at 8 pre-determined reference points was measured, including bilateral nasofrontal (NF), zygomaticofrontal (ZF), barrel stave (BS), and tenon extension (TE). Main Outcomes Measure: Measured discrepancy in millimeters between AR guides and 3D-printed guides at the pre-determined reference points. Results: The anterior reference points (NF, ZF) had mean discrepancies ranging from 0.31 to 0.61 mm. The posterior points had mean discrepancies ranging from 1.39 to 3.28 mm (BS, TE). There was no statistically significant difference found between the two modalities at any reference point. Conclusions: AR craniotomy guides had a high level of accuracy, particularly at the anterior reference points. AR guides demonstrated feasibility as an alternative to 3D-printed craniotomy guides, in-vitro. Further research is required to translate this novel application to cadaver models and improve precision at posterior landmarks.