Three-Dimensional Morphological Changes in the Upper Airway After Maxillary Reconstruction With an Anterolateral Thigh Flap

Abstract

BackgroundReconstruction of maxillary defects may lead to changes in the upper airway. These changes may cause postoperative airway obstruction issues. PurposeThe purpose was to evaluate the postoperative changes in the upper airway following maxillary reconstruction with an anterolateral thigh flap (ALTF) and to identify the factors associated with these changes. Study design, setting, sampleThis retrospective cohort study involved 26 patients who underwent maxillectomy for maxillary tumors, followed by reconstruction using an ALTF. Patients with a history of upper respiratory system disease and sleep-disorder breathing were excluded. Predictor variableThe predictor variable was the residual rate of ALTF volume (ALTF-RS), calculated as the ratio of ALTF volume at 6 months post-surgery (T2) to that at 2 weeks post-surgery (T1). The outcome variablesThe outcome variables were the upper airway parameters. The upper airway was assessed at 3 time points: one week preoperatively (T0), T1, and T2. Ratios were used to represent airway changes over time. CovariatesThe covariates are age, sex, Brown classification, body mass index (BMI), hypertension, neck dissection, and tracheostomy, etc. AnalysesAirway measurement differences between the three time points were analyzed by one-way ANOVA. Pearson correlation and Spearman correlation analysis were used to analyze the correlation coefficients between airway changes and ALTF-RS. Statistical significance was established at a P value < 0.05. ResultsThe sample included 26 subjects with a mean age of 55.6±15.2 years and 15/26 (57.7%) were male. Compared to T0, the nasopharyngeal and retropalatal airway volumes at T1 significantly decreased (P<0.05) but recovered or surpassed preoperative levels by T2. The minimum cross-sectional airway area (S-min) significantly decreased by T1 (P < 0.05), but increased by T2 (P<0.05). The narrowest airway section was predominantly in the palatopharyngeal airway. The airway changes of T2/T1 and ALTF-RS were not correlated (P > 0.05) except for anterior-inferior point of CV4 cross-sectional area (P < 0.05). Conclusions and RelevanceThe volumetric changes in the airway were not associated with ALTF-RS. The substantial narrowing of S-min at T1 emphasized the need for vigilant airway management in these patients.