Investigating the influence of syndromic craniosynostosis subtypes on midface measurement using generalized estimating equation approach

Authors

• Mohamad Norikmal Fazli Hisam, Universiti Malaya
• Norli Anida Abdullah, Universiti MalayaFollow
• Norlisah Mohd Ramli, Universiti Malaya
• Nur Anisah Mohamed, Universiti MalayaFollow
• Firdaus Hariri, Universiti Malaya
• Lantian Zheng, Universiti Malaya

Document Type

Article

Publication Date

1-2026

Abstract

Introduction: Studies have been conducted to investigate the changes of midface measurements using regression models with the assumption that the midface measurements in patients with syndromic craniosynostosis (SC) follow normal skull development. However, there is a potential that these changes may be influenced by the underlying SC subtypes. Objective: To investigate the influence of SC subtypes on the relationship between midfacial and cranial measurements using multiple linear regression (MLR) and generalized estimating equations (GEE). Method: Maxillary and zygomatic landmarks were measured from computed tomography scans of 37 SC patients (Apert, Crouzon, Pfeiffer) and 20 normal skulls. MLR models were fitted to combined and separate SC subtypes. GEE was applied to the combined dataset to cater correlation within SC subtypes, using three correlation structures: independence, exchangeable, and autoregressive (AR1). GEE and MLR estimates were compared. Results: Midface measurements of ANS-PNS, N-ANS, and ZMsL-ZMsR were strongly influenced by SC subtypes, as shown by a drop in R2 when SC subtypes were combined in the regression model (e.g., N-ANS: 0.9511 to 0.3344). GEE confirmed this finding, showing that ZMsL-ZMsR follows AR1 correlation structure within each SC subtype. On average, ZMsL-ZMsR increased by 0.1836 mm per additional month of age, 0.1107 mm for each unit increase in N-S-BA, and 0.0180 mm for each unit increase in S-N. Conclusion: SC subtypes exert influence on midface measurements. These findings provide practical guidance for surgeons to estimate average changes in midface measurement across SC subtypes based on age and cranial base measurements.

Keywords

Craniosynostosis, Generalized estimating equation, Midface, Cranial base, Syndromic craniosynostosis subtypes

Publication Title

Asian Journal of Surgery

ISSN

1015-9584

DOI

10.1016/j.asjsur.2025.08.261

Recommended Citation

Hisam, Mohamad Norikmal Fazli; Abdullah, Norli Anida; Mohd Ramli, Norlisah; Mohamed, Nur Anisah; Hariri, Firdaus; and Zheng, Lantian, "Investigating the influence of syndromic craniosynostosis subtypes on midface measurement using generalized estimating equation approach" (2026). Research Publications (2026 to 2030). 37.
https://knova.um.edu.my/research_publications_2026_2030/37

Volume

49

Issue

1

First Page

27

Last Page

35

Publisher

Elsevier