Abstract
Polysomonography is useful for assessing the severity of sleep breathing disorder, including obstructive sleep apnea hypopnea syndrome. The clinical condition is difficult to understand completely, however, based on the apnea hypopnea index (AHI) alone, however, and longitudinal change of shape in the upper airway must be clarified. Most diagnoses of obstructive sites in the upper airway were diagnosed statically, so we attempted to assess changes in upper airway shape using dynamic magetic resonance imaging (MRI), emphasizing the movement of tongue and lower chin, to analyze the relationship between AHI.Subjects were 62 patients with sleep breathing disorder examined by nocturnal polysomnography and dynamic MRI, assessing the change of shape in the upper airway. We concluded that : the group whose rotation angle of the tongue exceeded 6° and that the group whose distance of lower chin movement was longer during sleep than while awake were severe cases.
