Comparison of findings between clinical examinations and drug-induced sleep endoscopy in patients with obstructive sleep apnea syndrome

The Velum, Oropharynx, Tongue base and Epiglottis (VOTE) classification on drug-induced sleep endoscopy (DISE) is used widely for obstructive sleep apnea (OSA) syndrome, though research into comparative physical examinations with VOTE on DISE is still limited. The aim of this study was to evaluate the relationship between the findings of physical examinations and DISE in patients with OSA. Fifty-five patients with OSA were enrolled in this retrospective study. All of the patients received clinical explorations including a Brodsky classification, a modified Mallampati score (MMS), a modified Friedman’s staging system, and a Muller’s test. Drug-induced sleep endoscopy was further evaluated in the operating room. There were significant relationships between Brodsky classification, modified Friedman’s staging system, Muller’s test and oropharynx collapse during DISE (P < 0.05). Brodsky classification, MMS, modified Friedman’s staging system and retropalatal lateral-to-lateral (L–L) collapse of Muller’s test were significantly correlated with VOTE count (P < 0.05). The concordance between VOTE under DISE and Brodsky classification or modified Friedman’s staging system was moderate. In contrast, the concordance between VOTE under DISE and MMS or Muller’s test was slight. The study revealed that Brodsky classification and Friedman staging had a significant relationship with DISE on the velum and oropharynx, but the level of tongue base is uncertain between DISE and MMS. Correlation of awake evaluation of tongue base is still not correlated to the DISE findings. Pre-treatment evaluation of DISE is still warranted.