Based on previous studies, repeated narrowing of the upper airway is pathogenetic mechanism in obstructive sleep apnea (OSA) and subjects with OSA suffer from limited airflow from the nasal cavity. Upper airway narrowing predisposes the pharyngeal wall to collapse due to increased negative pressure, faster airflow, and higher airway resistance [1
]. More collapsible airway causes sleep-related symptoms, such as loud snoring and apneic events, and leads to fatigue, daytime sleepiness, and systemic complications if those symptoms are not properly managed in subjects with OSA [3
]. The upper airway narrowing occurs at multiple structures, including the soft palate, uvula, palatine tonsils, lateral pharyngeal walls, and the tongue base [6
]. In particular, the lateral wall of oropharynx is composed of several muscular structures, such as the palatopharyngeus, superior pharyngeal constrictor, and palatoglossus muscles, in addition to the palatine tonsils and lymphoid tissues around soft palate. Retropalatal circumferential narrowing due to lateral pharyngeal wall collapse has been documented to be a critical structural cause of OSA but so far, its clinical significance has been underestimated in subjects undergoing sleep surgery [11
]. Combined oropharynx, lateral pharyngeal wall, and velum obstruction are considered the most dominant anatomic characteristics of OSA, and the lateral pharyngeal wall is more collapsible or thicker in subjects with severe OSA than in normals or those with mild OSA [12
]. Actually, complete lateral pharyngeal wall narrowing may be closely related to higher apnea–hypopnea index (AHI) scores, and excessive lateral pharyngeal collapsibility is seen in subjects with OSA who show a relapse of snoring or apneic events after surgery [13
]. Previous clinical research has demonstrated the clinical benefits of palatal surgeries for OSA with lateral pharyngeal wall collapse, including relief of subjective symptoms and improvement of sleep parameters [8
], and diverse surgical techniques such as lateral pharyngoplasty, relocation pharyngoplasty, and expansion sphincter pharyngoplasty (ESP) to improve lateral pharyngeal wall narrowing and intensify the stability of the lateral pharyngeal wall have been introduced [13
The posterior palatal pillars have excessive mucosa tissue (webbing) with significant redundancy, which is an important anatomical structure that contributes to increase of lateral pharyngeal wall collapse. Soft-palate webbing flap pharyngoplasty has recently been introduced to reshape the soft-palate webbing without tonsillectomy [19
]. Soft-palate webbing flap pharyngoplasty may offer good benefits for creating stability in the lateral pharyngeal walls resulting in the reduction of the number of apneic events or snoring intensity without considerable postoperative pain.
In this study, we aimed to evaluate the therapeutic outcomes of soft-palate webbing flap pharyngoplasty in subjects with OSA or primary snoring and to determine the favorable indications of this procedure in the subjects with lateral pharyngeal wall collapse.