Assessment of the efficacy and analysis of prognostic factors of flap division for postoperative airway obstruction following posterior pharyngeal flap.

Objectives: Flap division is the primary method for treating postoperative airway obstruction following pharyngeal flap surgery. However, a discussion on the treatment effectiveness and prognosis of this surgery is lacking. Therefore, this study aims to explore the effectiveness of flap division in improving airway obstruction and hyponasality after pharyngoplasty and to analyze the risk factors for postoperative complications.

Methods: A retrospective review was conducted on the data of all patients who underwent flap division following pharyngeal flap for airway obstruction at our institution. Pre- and post-operative assessments of ventilation, speech, and related factors were performed using the nasal obstruction symptom evaluation scale, speech evaluation scale, nasopharyngeal fiberscope, and lateral cephalometric radiographs. A nasopharyngeal fiberscope was utilized to observe the airway port of the patients, velopharyngeal closure, and the mobility of the lateral pharyngeal walls. Lateral cephalometric radiographs were employed to evaluate the patient's maxillomandibular relationship and adenoid dimensions. A logistic regression model incorporating univariate analysis and multivariate analyses was established to identify the prognostic factors influencing the occurrence of persistent postoperative airway obstruction and hypernasality.

Results: Among the 63 patients, 56 patients (88.9%) experienced a reduction in the severity of airway obstruction postoperatively but 20 patients (31.7%) still presented with moderate-to-severe airway obstruction. Age at surgery (P=0.023) and adenoid hypertrophy (P=0.003) were significantly associated with persistent postoperative airway obstruction. All 39 individuals exhibiting preoperative hyponasality demonstrated effective resolution after flap division, and 11 patients (17.5%) experienced mild hypernasality postoperatively. Unilateral port obstruction (P=0.004) and BMI (P=0.027) were identified as potential independent factors influencing the development of postoperative hypernasality.

Conclusions: Flap division is an effective measure for improving postoperative airway obstruction and hyponasality following pharyngeal flap, although some patients may continue to experience persistent airway obstruction and develop hypernasality after division. Age at surgery and adenoid hypertrophy are prognostic factors for persistent airway obstruction following flap division. Unilateral/bilateral nasal airway obstruction and BMI are related factors for post-operative hypernasality.