[Magnetic resonance imaging of the upper airway structure of children with sleep disordered breathing].

Objective: To investigate the upper airway structure of sleep-disordered breathing children.

Methods: Seventy three children with obstructive sleep apnea hypopnea syndrome (OSAHS), 53 children with primary snoring (PS) and 40 control subjects underwent pharyngeal magnetic resonance imaging (MRI). Upper airway structure images were analyzed and measured.

Results: The cross-section area of the nasopharyngeal and palatopharyngeal airway in subjects with OSAHS and PS are smaller (P < 0.01) than that of the control group. The cross section area of OSAHS patients are smaller than that of PS subjects (P < 0.01). The above parameter of oropharyngeal airway in OSAHS patients is smaller than that of control group (P < 0.01), but no statistic difference compared with that of PS subjects. The cross-section area and length of the adenoid in OSAHS group are bigger and longer than that of PS group (P < 0.01) and bilateral tonsils are larger (P < 0.01); in OSAHS patients the cross-section area of the soft palate is larger and the length of the soft palate is longer (P < 0.01) than that of PS group, while this parameter of PS group is similar to that of the control group. And the maximum width of the soft palate, the cross-section area of bilateral fat pad, bilateral pterygoid and tongue are similar among OSAHS, PS and the control group. The skeletal measurement: the length of H-C2C3 in subjects with OSAHS is longer (P < 0.01); The angle(alpha) in OSAHS patients is smaller (P < 0.01) than that of other 2 groups. The angle (beta), the cross-section area of the mandible, the spine-clivus oblique, the length of the hard palate and the distance of the mandible are similar among the three groups.

Conclusions: In children with OSAHS or PS, the upper airway is restricted by both the adenoid and tonsils; however, the soft palate is also larger in OSAHS, adding further restriction. Otherwise, downward movement of the hyoid bone and decreasing of the angle (alpha) in OSAHS influence laryngopharynx airway. MRI is of clinical significance for evaluating OSAHS children's upper airway.