# Long-term morphometric and functional outcomes of frontofacial advancement in syndromic craniosynostosis

## TL;DR

This study examines how different frontofacial surgeries affect airway volume and function in patients with syndromic craniosynostosis over time.

## Contribution

The study provides longitudinal data on airway changes and functional outcomes following various frontofacial surgical techniques.

## Key findings

- All surgical techniques increased nasopharyngeal airway volume by 111.0% post-operatively.
- Each millimeter of midfacial advancement increased airway volume by 545 mm3 regardless of the surgical method.
- Midface advancement showed some long-term relapse but airway improvements were sustained.

## Abstract

Frontofacial surgery increases airway volumes, but little is known about how various surgical techniques affect the upper airway in the short- and long-term. The present study addresses this gap by analyzing longitudinal volumetric, craniometric, and functional outcomes following LeFort III (LFIII), monobloc, and monobloc with LeFort II (LFII) procedures for midface hypoplasia in syndromic craniosynostosis.

Patients with syndromic craniosynostosis who underwent frontofacial surgery were included. Three-dimensional reconstructions of the pre- and postoperative nasopharyngeal airways were generated using Materialize Mimics. Surgical technique, airway changes, anterior facial movement, polysomnography data, and demographics were analyzed.

Forty-one patients who underwent 45 procedures were included: 24 LFIII, 18 monoblocs, and 3 monoblocs with LFII. The median duration of follow-up was 7.1 years (IQR: 4.5–9.5; range: 1.8–12.7). Nasopharyngeal airway volume increased post-operatively by 111.0% (interquartile range: 36.2–172.5) across all cohorts, with both nasal and pharyngeal airway increasing on early (< 12 months) and late (> 12 months) follow-up (p < 0.05). All midface surgical techniques increased airway volumes similarly (p > 0.05). The midface was advanced on early post-operative imaging (anterior nasal spine-porion midpoint length: 72 (66–77) mm vs. 91 (85–95) mm), with some relapse (85 (80–99) mm) on later imaging. The airway expanded 545 (368–902) mm3 for each mm of sagittal advancement. Both OAHI and SpO2 nadir improved after surgery (p < 0.05).

Nasopharyngeal airway volume increases in the short and long term following LeFort III, monobloc, and monobloc with LeFort II procedures, even as the midface experiences some long-term sagittal relapse. Each millimeter of sagittal midfacial movement results in 545 mm3 of airway volumetric increase regardless of osteotomy choice.

The online version contains supplementary material available at 10.1007/s00381-025-07069-9.