SA1 - Evaluating the Efficacy of Postoperative Helmet Therapy in Syndromic vs. Non-Syndromic Craniosynostosis Following Open Cranial Vault Remodeling

Abstract:

Background: Postoperative helmet therapy is commonly used after endoscopic cranial vault remodeling (CVR) in patients with craniosynostosis. At our institution, helmet therapy is also routinely employed following open CVR. This study seeks to evaluate the effectiveness of postoperative helmet therapy (PHT) in reducing residual cranial asymmetry following open CVR, comparing outcomes between syndromic and non-syndromic patients.

Methods: A retrospective review of patients with craniosynostosis who underwent open CVR+PHT between 2016 and 2023 was conducted. Patients with available craniometric data were included. Pre- and post-helmet therapy measurements were assessed. Outcomes of interest included cephalic index (CI) and cranial vault asymmetry index (CVAI). T-tests were used to compare craniometrics between syndromic and non-syndromic cohorts. Paired t-tests and Wilcoxon signed-rank tests were used to compare pre- and post-helmet measurements for parametric and non-parametric data, respectively. One sample t-tests were used to compare post-helmet measurements to normocephalic standards, where a CVAI less than 3.5% and CI between 75-85% were considered normocephalic.¹

Results: Of 470 patients who underwent open CVR, 61 met inclusion criteria. Among these, 14 (23%) were syndromic and 44 (77%) were non-syndromic. The mean follow-up time was 2.6 ± 0.3 years. Median age at surgery was 8.2 months (Interquartile range [IQR]: 7.1, 10.2) and median age at start of PHT was 9.3 months (IQR: 7.7, 11.6), with no significant difference between cohorts (P > .05). The pre-helmet therapy CI was significantly higher in the syndromic cohort compared to the non-syndromic cohort (94.9 ± 10.2 vs 87.6 ± 8.5, P = .009). The post-helmet CI was significantly higher in the syndromic cohort compared to the non-syndromic cohort (89.4 ± 7.7 vs 84.4 ± 6.9, P = .024). The pre-helmet and post-helmet CVAI did not differ significantly between cohorts. Comparing pre- and post-helmet therapy measurements, the CI significantly improved in both the syndromic cohort (P = .002) and non-syndromic cohort (P < .001). CVAI significantly improved in both the syndromic (P = .030) and non-syndromic cohort (P < .001). Post-helmet CI and CVAI measurements in nonsyndromic patients were equivalent to normocephalic standards (P > .05). The syndromic cohort’s post-helmet CVAI was equivalent to normocephalic standards (P > .05), but the CI remained significantly greater than normocephalic standards (P = .002).

Conclusion: Postoperative helmet therapy following open CVR effectively improved both cranial shape and symmetry in patients with both syndromic and nonsyndromic craniosynostosis. PHT should be considered in both syndromic and nonsyndromic patients. Physicians should be aware of the potential for residual brachycephaly in syndromic patients and counsel families accordingly.

1. Littlefield TR. Cranial remodeling devices: treatment of deformational plagiocephaly and postsurgical applications. Semin Pediatr Neurol. 2004;11(4):268-277.
Cephalic Index and Cranial Vault Asymmetry Index Calculations