Simulated Fronto-Orbital Advancement Achieves Reproducible Results in Metopic Synostosis

Background: Metopic synostosis results in trigonocephaly with bitemporal narrowing. Treatment involves differential fronto-orbital advancement, widening of the bitemporal region, and rounding the forehead. The purpose of this article was to implement three-dimensional surgical planning to treat metopic synostosis, including use of intraoperative templates, and to test the accuracy of the results. Methods: This is a prospectively analyzed series of retrospective patients with metopic synostosis. Consecutive cases treated by the authors involving a simulated computer-aided planning session were reviewed. Demographic data were tabulated, and three-dimensional quantitative data reviewed. Measurements obtained included bifrontal angle, temporal advancement, and bitemporal distance and widening. Preoperative, simulated, and actual results were compared and analyzed using the t test. Results: Five infants with metopic synostosis treated by this method were included (3 boys, 2 girls). The endocranial bifrontal angle-changed from 111.25 degrees preoperatively to 148.58 degrees postoperatively (P = 0.0001) and simulated 145.62 degrees (compared with actual 148.58) (P = 0.5099). The bitemporal distance preoperative averaged 73.72mm, compared with actual of 89.78mm (P = 0.019), and was simulated to 89.28mm (vs actual 89.78) (P = 0.8815). The surgically planned advancement and expansion were similar compared with actual (P = 0.591, 0.806, and 0.806), respectively. Conclusions: The results show that simulated surgical planning can accurately and reproducibly be translated to actual surgical outcome during fronto-orbital advancement for trigonocephaly. The treatment goals for metopic synostosis are conserved and effectively achieved, including lateral orbital advancement, widening of the endocranial bifrontal angle, bitemporal expansion, and rounding of the forehead.