A Novel Protocol for Planning and Navigation in Craniofacial Surgery: A Preclinical Surgical Study

Purpose: In modern craniofacial surgery, the accuracy of osteotomies plays a central role in surgical technique. To reach a higher level of accuracy, many centers use virtual presurgical planning. In the past decade, some surgeons also have applied navigational approaches to craniofacial procedures. In this work, a novel protocol for surgical planning and intraoperative navigation is described and validated in a preclinical setting to determine its accuracy in guiding osteotomies. Materials and Methods: This study was based on planning a set of osteotomies using 3-dimensional models of computed tomographic images of human skulls. The planned osteotomies were reproduced on real skulls using an optical infrared navigation system. Positions of the performed osteotomies and planned osteotomies were compared. Results were described as the mean positional error and as a Lin concordance coefficient. The Bland-Altman interval of agreement also was defined to assess a range that could include 95% of possible errors. Results: The mean error was 0.044 mm (95% confidence interval [CI], -0.128 to +0.216), the Lin concordance interval was 0.999 (95% CI, 0.999-1.000), and the Bland-Altman limit of agreement ranged from -1.500 to +1.589 mm. Conclusions: These results show a submillimetric mean error and a very narrow interval of agreement, providing preclinical validation of this new protocol and suggesting that it could be applied in a clinical setting.