Differences of Upper Airway Morphology According to Obesity: Study with Cephalometry and Dynamic MD-CT.
- Author:
Tae Hoon KIM
1
;
Bum Soo CHUN
;
Ho Won LEE
;
Jung Soo KIM
Author Information
1. Department of Otorhinolaryngology-Head and Neck Surgery, Kyungpook National University School of Medicine, Daegu, Korea. sookim@knu.ac.kr
- Publication Type:Original Article
- Keywords:
Snoring;
Sleep apnea;
CT scan;
Obesity
- MeSH:
Apnea;
Blood Pressure;
Cephalometry;
Humans;
Hyoid Bone;
Neck;
Obesity;
Polysomnography;
Sleep Apnea Syndromes;
Snoring
- From:Clinical and Experimental Otorhinolaryngology
2010;3(3):147-152
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVES: We investigated difference of parameters of polysomnography, cephalometry and dynamic multi-detector computerized tomography (MD-CT) in wake and sleep states according to obesity. METHODS: We evaluated 93 patients who underwent polysomnography and cephalometry. MD-CT was performed in 68 of these 93 patients. Fifty-nine and 34 patients were classified as obese and non-obese, with obesity defined as BMI > or =25. Cephalometry results were analyzed for 12 variables. Using the MD-CT, we evaluated dynamic upper airway morphology in wake and sleep states and divided the upper airway into four parts named as high retropalatal (HRP), low retropalatal (LRP), high retroglossal (HRG), and low retroglossal (LRG). A minimal cross sectional area (mCSA) and collapsibility index (CI) were calculated for each airway level. RESULTS: Diastolic blood pressure (P=0.0005), neck circumference (P<0.0001), and apnea-hypopnea index (P<0.0001) were statistically significantly different between the obese and non-obese group. Among 12 cephalometric variables, there was a significant difference in only the distance from mandibular plane to hyoid bone (P=0.003). There was statistical difference in CI of HRG and LRG in sleep state (P=0.0449, 0.0281) but no difference in mCSA in wake and sleep states. CONCLUSION: The obese group had more severe sleep apnea than the non-obese group. We believe that the increased severity of apnea in the obese group may be have been due to increased collapsibility of the upper airway rather than decreased size of the upper airway.