title: Sleep-disordered breathing, pharyngeal size and soft tissue anatomy in children.
abstract: We tested the hypothesis that pharyngeal geometry and soft tissue dimensions correlate with the severity of sleep-disordered breathing. Magnetic resonance images of the pharynx were obtained in 18 awake children, 7-12 yr of age, with obstructive apnea-hypopnea index (OAHI) values ranging from 1.81 to 24.2 events/h. Subjects were divided into low-OAHI (n = 9) and high-OAHI (n = 9) groups [2.8 +/- 0.7 and 13.5 +/- 4.9 (SD) P < 0.001]. The OAHI correlated positively with the size of the tonsils (r2 = 0.42, P = 0.024) and soft palate (r2 = 0.33, P = 0.049) and inversely with the volume of the oropharyx (r2 = 0.42, P = 0.038). The narrowest point in the pharyngeal airway was smaller in the high-compared with the low-OAHI group (4.4 +/- 1.2 vs. 6.0 +/- 1.3 mm; P = 0.024), and this point was in the retropalatal airway in all but two subjects. The airway cross-sectional area (CSA)-airway length relation showed that the high-OAHI group had a narrower retropapatal airway than the low-OAHI group, particularly in the retropalatal region where the soft palate, adenoids, and tonsils overlap (P = 0.001). The "retropalatal air space," which we defined as the ratio of the retropalatal airway CSA to the CSA of the soft palate, correlated inversely with the OAHI (r2 = 0.49, P = 0.001). We conclude that 7- to 12-yr-old children with a narrow retropalatal air space have significantly more apneas and hypopneas during sleep compared with children with relatively unobstructed retropalatal airways.
authors.affiliation: Department of Physiology, University of Arizona, Tucson, Arizona 85721, USA. Fregosi@u.arizona.edu
authors.forename: R F
authors.initials: RF
authors.lastname: Fregosi
authors.forename: S F
authors.initials: SF
authors.lastname: Quan
authors.forename: K L
authors.initials: KL
authors.lastname: Kaemingk
authors.forename: W J
authors.initials: WJ
authors.lastname: Morgan
authors.forename: J L
authors.initials: JL
authors.lastname: Goodwin
authors.forename: R
authors.initials: R
authors.lastname: Cabrera
authors.forename: A
authors.initials: A
authors.lastname: Gmitro
mesh_terms: D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010160:Palate, Soft / Q000473:pathology; D014066:Palatine Tonsil / Q000473:pathology; D010614:Pharynx / Q000473:pathology*; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000473:pathology*; D014851:Wakefulness