Magnetic Resonance Imaging of the Upper Airway Structure of Children with Obstructive Sleep Apnea Syndrome

Division of Pulmonary Medicine, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104-4399, USA.
American Journal of Respiratory and Critical Care Medicine (Impact Factor: 13). 09/2001; 164(4):698-703. DOI: 10.1164/ajrccm.164.4.2101127
Source: PubMed


The anatomical relationships between lymphoid, bony, and other tissues affecting the shape of the upper airway in children with obstructive sleep apnea syndrome (OSAS) have not been established. We therefore compared the upper airway structure in 18 young children with OSAS (age 4.8 +/- 2.1 yr; 12 males and 6 females) and an apnea index of 4.3 +/- 3.9, with 18 matched control subjects (age, 4.9 +/- 2.0 yr; 12 males and 6 females). All subjects underwent magnetic resonance imaging under sedation. Axial and sagittal T1- and T2-weighted sequences were obtained. Images were analyzed with image-processing software to obtain linear, area, and volumetric measurements of the upper airway and the tissues comprising the airway. The volume of the upper airway was smaller in subjects with OSAS in comparison with control subjects (1.5 +/- 0.8 versus 2.5 +/- 1.2 cm(3); p < 0.005) and the adenoid and tonsils were larger (9.9 +/- 3.9 and 9.1 +/- 2.9 cm(3) versus 6.4 +/- 2.3 and 5.8 +/- 2.2 cm(3); p < 0.005 and p < 0.0005, respectively). Volumes of the mandible and tongue were similar in both groups; however, the soft palate was larger in subjects with OSAS (3.5 +/- 1.1 versus 2.7 +/- 1.2 cm(3); p < 0.05). We conclude that in children with moderate OSAS, the upper airway is restricted both by the adenoid and tonsils; however, the soft palate is also larger in this group, adding further restriction.

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    • "The soft-tissue morphology of the upper airway that may related to pediatric SDB includes narrowed pharyngeal airways, and larger adenoids, tonsils and soft palates [8-10]; the related hard-tissue morphology includes an increased intermaxillary angle, a retrognathic mandible [11,12], an increased mandibular angle, a longer lower anterior facial height [13,14], narrow dental arches and deep palatal height [15,16], and an inferiorly positioned hyoid bone [17,18]. "
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    Head & Face Medicine 09/2014; 10(1):38. DOI:10.1186/1746-160X-10-38 · 0.85 Impact Factor
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    • "Kawashima 2000 [60] III À 15 with OSAS À 4.7 (range 3e5) y Cephalometry The study concluded that: 1) sleep apnea was often associated with mandibular retrognathia, 2) the lower incisors tended to exhibit a retrocline, 3) there were no significant differences in angular and linear measurements in the cranial base, and 4) the apneic children had a narrower epipharyngeal airway space. Arens 2001 [63] "
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