Posterior pillar hypertrophy as a novel anatomical predictor of surgical success in obstructive sleep apnea

Abstract

Sleep apnea surgery is effective only for selecting patients, making it crucial to identify those who will benefit. This study aimed to introduce a novel anatomical index for selecting patients with favorable surgical outcomes. A retrospective review was conducted on patients with obstructive sleep apnea who underwent multilevel surgery by a single surgeon at a tertiary medical institution between 2012 and 2021. Anatomical parameters, endoscopic images, and pre- and postoperative polysomnography reports were analyzed. Some patients exhibited posterior pillar hypertrophy (PPH), where the palatopharyngeal muscle is thicker than normal. To assess the effects of PPH exclusively, patients were randomly selected and subjected to propensity matching. Logistic regression analysis identified tonsil grade, body mass index, and posterior pillar thickness as significant predictors of surgical success. The success rates were significantly different between the PPH(+) and normal control PPH(-) groups, with 51.9% success in the PPH(+) group compared to 40.7% in the PPH(-) group. Additionally, the PPH(+) group showed a significant increase in the apnea-hypopnea index and oxygen desaturation index postoperatively. The presence of posterior pillar hypertrophy serves as an important anatomical predictor of surgical success in obstructive sleep apnea treatment. This index helps in choosing patients and planning surgeries, potentially enhancing treatment.