Use of Modified Swallow Study to Measure Posterior Airway Space in Obstructive Sleep Apnea Patients

Abstract

Objectives:

Obstructive sleep apnea affects over 15% of the population, presenting a major health burden. Research has focused on exploring imaging modalities that supplement polysomnography, eliciting potential sites of airway obstruction. While computed tomography (CT) imaging and sleep endoscopy have been used to accurately assess the posterior airway space (PAS), sedated endoscopy is invasive, and repeated CT imaging risks higher radiation exposure and does not assess the dynamics of the tongue base and PAS. We propose the use of modified barium swallow study as a simple modality to measure PAS. Advantages include its simplicity, lower radiation, and dynamic tongue base visualization, which may help predict surgical outcomes. We hypothesize cephalometric measurements obtained using modified barium swallow (MBS) will correlate well with CT.

Methods:

Retrospective chart review, tertiary care hospital. Thirty-six adult patients who underwent both CT imaging and MBS for head and neck cancer were included. Cephalometric measurements of the PAS were obtained using each imaging modality. Statistical analysis focused on correlating measurements taken using CT or MBS.

Results:

The average PAS measurements were 12.53 ± 1.81 mm and 12.80 ± 1.75 mm when using MBS and CT imaging, respectively. There were no statistical differences based on age, sex, or cancer site. In comparing the 2 modalities, Pearson correlation between CT and MBS measurements revealed an extremely significant positive correlation between r = 0.6382 and 0.8932 (P < .0001).

Conclusions:

Cephalometric measurement of the PAS using MBS appears to correlate well with CT imaging. These data suggest MBS may be an effective way to assess the PAS in patients with OSA.