Part of the paper was presented with the title “Three-Dimensional Computed Tomographic Evaluation of Airway and Craniofacial Changes in Adult Patients With Obstructive Sleep Apnea Who Underwent Segmental Maxillo-Mandibular Rotational Advancement” at the SLEEP 2010 24th Annual Meeting of the Associated Professional Sleep Societies, LLC (APSS), San Antonio, Texas, U.S.A., June 5–9, 2010.
Article first published online: 6 MAY 2011
Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.
Volume 121, Issue 6, pages 1336–1347, June 2011
How to Cite
Lin, C.-H., Liao, Y.-F., Chen, N.-H., Lo, L.-J. and Chen, Y.-R. (2011), Three-dimensional computed tomography in obstructive sleep apneics treated by maxillomandibular advancement. The Laryngoscope, 121: 1336–1347. doi: 10.1002/lary.21813
This study was supported by the National Science Council, Taiwan (NSC 95-2314-B-182-020-Yu-Ray Chen MD-PI). The authors have no other funding, financial relationships, or conflicts of interest to disclose.
- Issue published online: 19 MAY 2011
- Article first published online: 6 MAY 2011
- Manuscript Accepted: 9 MAR 2011
- Manuscript Revised: 3 MAR 2011
- Manuscript Received: 23 SEP 2010
- Three-dimensional computed tomography;
- obstructive sleep apnea;
- maxillomandibular advancement;
- upper airway size;
- Level of Evidence: 2c.
The goal of this study was to understand the changes to the head and neck musculoskeleton and the pharyngeal airway after surgery. We tested the correlation between the changes in the skeleton and pharyngeal airway and the apnea-hypopnea index (AHI).
Prospective, noncontrolled study.
In a pilot study, 12 consecutive subjects (3 women, body mass index: 22.4 Kg/m2 ± 2.7, AHI: 35.9/sec ± 18.0) with Class II dentoskeletal malocclusion and high mandibular plane underwent segmental maxillomandibular rotational advancement (SMMRA). Subjects underwent overnight polysomnography and three-dimensional computed tomography scanning of the head and neck before and 3 months after surgery. Linear, angular, and area measurements were obtained from skeletal images placed in the Frankfort horizontal position and from horizontal cross-sectional tomograms derived from the upright pharyngeal airway. Skeletal movements, dimensional changes of the airway, and correlations between measurements and AHI were calculated. A linear regression model was generated using significant bivariate correlations.
The AHI was significantly reduced to 4.6/sec ± 4.1 with improvement in the nadir oxygen saturation from 83.0% ± 7.2 to 90.6% ± 3.6 after SMMRA. Following skeletal advancement, the hyoid bone was advanced and elevated by 7.5 mm ± 2.9 and 6.7 mm ± 5.5, respectively; the cervical spine was rotated forward by 4.6° ± 2.8; and the airway length was shortened by 6.8 mm ± 4.0 (all P < .01). Variable improvement of airway dimensions was noted at each horizontal level. A quadratic regression model was derived using the measurements of the Sella-Nasion-B point angle and AHI (Rsq = 0.557, sig = 0.000).
Dimensions of pharyngeal airway were correlated with dimensions of craniofacial skeleton. Sella-Nasion-B point angle could be used as a guidance in achieving normalized AHI after surgery.