Effect of Modified Uvulopalatopharyngoplasty without Tonsillectomy on Obstructive Sleep Apnea: Polysomnographic Outcome and Correlation with Drug-Induced Sleep Endoscopy

OBJECTIVE: Uvulopalatopharyngoplasty (UPPP) is a common procedure for the treatment of obstructive sleep apnea (OSA) and is usually initiated with the resection of palatine tonsils. Because tonsillectomy potentially contributes to complications, minimally invasive upper airway surgeries have been proposed for OSA therapy. Whether tonsillectomy is always essential for UPPP remains unclear, particularly for patients with small tonsils. The purpose of this study was to present the effect of modified UPPP without tonsillectomy (UPsT) on patients with OSA and attempt to select the candidates for this procedure. METHODS: This is a retrospective cohort study of patients with OSA, with tonsil size of grade 0–2, and with only retropalatal obstruction in drug-induced sleep endoscopy (DISE). The patients underwent UPsT at a tertiary center from November 2017 to December 2019. The sleep study was performed before and at least 3 months after surgery. The demographics, surgical outcomes, and staging patterns of preoperative DISE were recorded. The correlation between surgical outcome and DISE was also established. RESULTS: A total of 22 adults with an average age of 46.5 years [interquartile range: 40 to 60 years] completed the follow-up study. Their apnea–hypopnea index (AHI) and Epworth sleepiness scale values improved significantly after surgery. Of the 17 patients with partial collapse and complete anteroposterior collapse (APC) at the velum, 16 presented good responses to UPsT. However, among the five patients with complete concentric collapse (CCC), only two (2/5, 40%) satisfied the criteria for surgical success. Furthermore, their follow-up AHI values were significantly higher than those of patients without CCC in DISE. CONCLUSION: UPsT was demonstrated to be an effective therapy for patients with OSA who had small tonsils and retropalatal obstruction in DISE. CCC in sleep endoscopy indicates a poorer surgical outcome than does complete APC and partial collapse at the velum.