Use of morphological indicators to predict outcomes of palatopharyngeal surgery in patients with obstructive sleep apnea.

There is no consensus on how to quantify the abnormality of upper airway structures in patients with obstructive sleep apnea (OSA). This research aimed to use morphological indicators as clinical predictors to correlate morphological stage and surgical results in OSA patients. One hundred and five patients with OSA received palatopharyngeal surgery, i.e. extended uvulopalatal flap (EUPF). Morphological indicators including modified Mallampati grade (MMP), tonsil size, and body mass index were used to stage OSA patients preoperatively. Change of respiratory disturbance index (RDI) was used to monitor change of sleep apnea events. Success rates were compared among patients of different morphological stages. One year after EUPF, the success rates of EUPF in stage I, II, and III patients were 100, 92.9 and 61.4%, respectively. Change of RDI was significantly correlated with MMP and tonsil size. MMP and tonsil size were predictive of the change of RDI (R(2) = 0.29). Morphological stage may serve as a reliable selection criterion for patients undergoing EUPF surgery and can significantly predict the change of sleep apnea events following EUPF surgery.