Longitudinal analysis of cranial growth using comprehensive craniometric measurements after fronto-orbital advancement in coronal craniosynostosis.

Objective: The objective of this study was to investigate the longitudinal changes in cranial growth following fronto-orbital advancement (FOA) surgery in patients with unilateral and bilateral coronal craniosynostosis.

Methods: This retrospective review analyzed head circumference (HC) and CT data during preoperative (T0), immediate postoperative (T1), and final follow-up (T2) visits in 40 patients (23 female, 17 male) who underwent FOA using either the open approach or distraction osteogenesis (DO) between 1987 and 2018. The mean follow-up period was 90.62 months. The z-scores of HC, CT-based intracranial volume, anteroposterior diameter (APD), biparietal diameter (BPD), and cranial height (CH) were calculated using sex- and age-specific standards. Logistic regression analysis was performed.

Results: While the z-scores of HC, intracranial volume, and BPD remained within the normal range, the z-scores of APD fluctuated between -2 and -1, and the z-scores of CH were > 2, indicating a substantial elevation compared with norms from T0 to T2. Age at surgery significantly influenced the z-scores of HC, BPD, and CH at T2 (all p < 0.05). Delayed surgical timing was correlated with increased BPD and CH z-scores from T1 to T2 (p = 0.007 and 0.019, respectively). The DO for FOA resulted in elevated HC z-scores at T2 and increased APD from T0 to T1, followed by a significant APD relapse from T1 to T2.

Conclusions: These findings suggest that delayed surgical timing may support better cranial growth, as indicated by increased HC at long-term follow-up. However, delayed timing is also associated with worsening abnormally elevated CH. Despite the immediate APD expansion and long-term HC increase with DO, potential relapse warrants caution. While intentional overcorrection of APD is recommended, careful consideration of surgical timing and planning is essential.