Imaging upper airway obstruction in obstructive sleep apnea

Polysomnography is considered the gold standard tool to establish the diagnosis and severity of obstructive sleep apnea (OSA) syndrome in children; however, it cannot provide information regarding the mechanism or location of upper airway obstruction during sleep. The present chapter will focus on the role of imaging modalities in evaluating childhood OSA and how they may advance our understanding of the anatomical and functional aspects of the disorder. Although routine imaging for children with OSA is not required, advanced imaging techniques are an important component of the evaluation for some children, including those with complex medical comorbidities, craniofacial anomalies, and persistent disease following first-line therapy. In this chapter, we emphasize studies using magnetic resonance imaging, since this technique is noninvasive and provides the most quantitative and reliable data without ionizing radiation. Lateral neck radiography, sleep fluoroscopy, computed tomography, and optical coherence tomography are also discussed.