本研究應用大渦法對於具成人阻塞型睡眠呼吸中止症的氣管空氣流動來進行模擬計
算。睡眠呼吸中止症是指當人處於睡眠狀態時，在上呼吸道(鼻咽、口咽以及喉部)出現
反覆性的塌陷，使得呼吸道堵塞，導致呼吸能力下降且費力，症狀嚴重者可能因呼吸
道完全堵塞而造成窒息。透過Apnea-hypopnoea index (AHI)來判斷睡眠呼吸中止症的
嚴重程度。然而，在不同的嚴重程度下，相對地治療的方法也有所不同，目前市面上
由許多非侵入性的治療方法舉凡止鼾牙套、持舌器以及連續性陽壓呼吸器等。其中，
連續性陽壓呼吸器是針對較嚴重病患的治療方法，患者必須在睡眠時配戴面罩，因此
有許多的患者無法適應治療上的不便，因而紛紛放棄治療。藉此，選擇外科手術方式
來治療睡眠呼吸中止症，不僅能解決適應不良的情況，還能有效且快速地改善呼吸道
塌陷的問題。本文以三位患有阻塞型睡眠呼吸中止症的病患，經過正顎手術後，探討
術前、術後以及術後一段時間的紊流流場狀態分析，並從病患的電腦斷層掃描圖轉換
重建成三維模型，運用大渦法來進行流場的數值模擬，以壓力、速度、流阻、噴流角
與窄縮率等分析結果來驗證該手術的效果，未來，能應用在臨床上，成為病患與醫生
之間的溝通橋樑。

Obstructive sleep apnea syndrome (OSAS) is a common disorder of adults, which is caused by repeated obstruction the upper airway during sleep. The effects of OSAS are not only the sleep quality but also the occurrence of disease such as hypertension, stroke and myocardial infarction. Apnea-hypopnoea index (AHI) is an acceptable measure for the severity of OSAS. Lots of treatments for patients with OSAS, it usually takes long time to adapt and inconveniently uses in life. Subsequently, many patients may give up the treatments because of adjustment disorder. Most of treatments are continuous positive airway pressure (CPAP) which is considered to be the standard treatments for patients with moderate-to-severe. Therefore, the patients who are more serious and unable to adapt will select surgical operations as their treatments for OSAS. In the present study, the preoperative, post-operative and after a period of time operation CT scan of upper airway by Maxillomandibular advancement (MMA) operation from patients are re-constructed and converted to in vitro three-dimensional models. The transitional/turbulent flow simulations during inspiration and expiration are studied using the Large Eddy Simulation (LES) technique in the in vitro 3D models of upper airway. Furthermore, the results show that the pressure drop, velocity, flow resistance, jet angle and stenosis of upper airway are significantly reduced after surgery and this model may be further applied for clinical evaluation in future.

Abdel-Rahman A., 2010. A Review of Effects of Initial and Boundary Conditions on
Turbulent Jets WSEAS TRANSACTIONS on FLUID MECHANICS 5, 257-275.
Ahmed S.A. and Giddens D.P., 1983. Velocity measurements in steady flow through axisymmetric
stenoses at moderate Reynolds number. J. Biomechanics 16, 505-516.
Boyd S.B., Walters A.S., Song Y. and Wang L., 2013. Comparative Effectiveness of Maxillomandibular
Advancement and Uvulopalatopharyngoplasty for the Treatment of Moderate
to Severe Obstructive Sleep Apnea. J Oral Maxillofac Surg 71, 743-751.
Cui X. and Gutheil E., 2017. Three-dimensional unsteady large eddy simulation of the
vortex structures and the mono-disperse particle dispersion in the idealized human
upper respiratory system. Journal of Aerosol Science 114, 195-208.
Cignoni P., Corsini M., and Ranzuglia G., 2008. MeshLab: an Open-Source 3D Mesh
Processing System ERCIM NEWS 73, 45-46.
De Backer J.W., Vanderveken O.M., Vos W.G., Devolder A., Verhulst S.L., Verbraecken
J.A., Parizel P.M., Braem M.J., Van de Heyning P.H., and De Backer W.A., 2007.
Functional imaging using computational fluid dynamics to predict treatment success of
mandibular advancement devices in sleep-disordered breathing. Journal of Biomechanics
40, 3708-3714.
Geuzaine C. and Remacle J.F., 2009. Gmesh. http://www.geuze.org/gmesh.
Guilleminault C., Stoohs R., Clerk A., Cetel M. and Maistros P., 1993. A cause of excessive
daytime sleepiness. The upper airway resistance syndrome. Chest 104, 781-787.
Greenshields C., 2015. OpenFOAM User Guide. Version2.4.0. OpenFOAM Foundation
Ltd.
Huynh J., Kim K.B. and McQuilling M., 2009. Pharyngeal Airflow Analysis in Obstructive
Sleep Apnea Patients Pre- and Post-Maxillomandibular Advancement Surgery. Journal
of Fluids Engineering 131, 091101-1-091101-10.
Jayesh S.R. and Bhat W.M., 2015. Mandibular advancement device for obstructive sleep
apnea: An overview. Journal of Pharmacy and Bioallied Sciences 7, S223-S225.
Jeong S.J., Kim W.S. and Sung S.J., 2007. Numerical investigation on the flow characteristics
and aerodynamic force of the upper airway of patient with obstructive sleep apnea
using computational fluid dynamics. Medical Engineering and Physics 29, 637-651.
Jin H.H., Fan J.R., Zeng M.J. and Cen K.F., 2007. Large eddy simulation of inhaled
particle deposition within the human upper respiratory tract. Aerosol Science 38, 257-
268.
Jasak H., Jemcov A. and Tukovic Z., 2007. OpenFOAM: A C++ Library for Complex
Physics Simulations. International Workshop on Coupled Methods in Numerical Dynamics
Karamanli H., Ozol D., Ugur K.S., Yildirim Z., Armut¸cu F., Bozkurt B. and Yigitoglu ¨
R., 2014. Influence of CPAP treatment on airway and systemic inflammation in OSAS
patients. Sleep Breath 18, 251-256.
Khan A., Ramar K., Maddirala .S, Friedman O., Pallanch J.F. and Olson E.J., 2009.
Uvulopalatopharyngoplasty in the Management of Obstructive Sleep Apnea:The Mayo
Clinic Experience. Mayo Clin Proc. 84, 795-800.
Lambert A.R., O’shaughnessy P.T., Tawhai M.H., Hoffman E.A. and Lin C.L., 2011.
Regional Deposition of Particles in an Image-Based Airway Model: Large-Eddy Simulation
and Left-Right Lung Ventilation Asymmetry. Aerosol Science and Technology
45, 11-25.
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.
Laryngoscope 121, 1336–1347.
McGown A. D., Makker H. K., Battagel J. M., L’Estrange P. R., Grant H. R. and Spiro S.
G., 2001. Long-term use of mandibular advancement splints for snoring and obstructive
sleep apnoea: a questionnaire survey. Eur Respir J 17, 462-466.
Mihaescu M., Murugappan S., Kalra M., Khosla S. and Gutmark E., 2008. Large Eddy
Simulation and Reynolds-Averaged Navier–Stokes modeling of flow in a realistic pharyngeal
airway model: An investigation of obstructive sleep apnea Journal of Biomechanics
41, 2279–2288.
Nithiarasu P., Hassan O., Morgan K., Weatherill N. P., Fielder C., Whittet H., Ebden P.
and Lewis K. R., 2008. Steady flow through a realistic human upper airway geometry.
Int. J. Numer. Meth. Fluids 57, 631-651.
Nie P, Xu X.L., Tang Y.M., Wang X.L., Xue X.C., Wu Y.D. and Zhu M., 2015. Computational
Fluid Dynamics Simulation of the Upper Airway of Obstructive Sleep Apnea
Syndrome by Muller Maneuver. J Huazhong Univ Sci Technol Med Sci 35, 464-468.
Ruehland W.R., Rochford P.D., O’Donoghue F.J., Pierce R.J., Singh P. and Thornton
A.T., 2009. The New Aasm Criteria for Scoring Hypopneas: Impact on the Apnea
Hypopnea Index. Sleep 32, 150-157.
Salim S.M. and Cheah S.C., 2009. Wall y+ Strategy for Dealing with Wall-bounded
Turbulent Flows. Proceedings of the International MultiConference of Engineers and
Computer Scientists, IMECS
Sagaut P., 2006. Large Eddy Simulation for Incompressible Flows. 3rd ed., SpringerVerlag,
Berlin, Germany.
Smagorinsky J., 1963. General circulation experiments with the primitive equations.
Monthly Weather Review 91, 99-164.
Sung S.J., Jeong S.J., Yu Y.S., Hwang C.J. and Pae E.K., 2006. Customized Threedimensional
Computational Fluid Dynamics Simulation of the Upper Airway of Obstructive
Sleep Apnea. Angle Orthodontist 76, 791-799.
Tangerina R.P., Martinho F.L., Togeiro S.M., Greg´orio L. C., Tufik S. and Bittencourt
L.R., 2008. Clinical and polysomnographic findings in class III obese patients. Rev Bras
Otorrinolaringol 74, 579-582.
Visualization and Interactive Media Laboratory VIML., 2012. Miil.
http://www.geuze.org/gmesh.
Wakayama T., Suzuki M. and Tanuma T., 2016. Effect of Nasal Obstruction on Continuous
Positive Airway Pressure Treatment:Computational Fluid Dynamics Analyses.
Analyses. PLoS ONE 11, e0150951.
Xu C., Sin S.H., McDonough J.M., Udupa J.K., Guez A., Arens R. and Wootton D.M.,
2006. Computational fluid dynamics modeling of the upper airway of children with
obstructive sleep apnea syndrome in steady flow. Journal of Biomechanics 39, 2043-
2054.
Zhang Z., Kleinstreuer C. and Kim C.S., 2002. Micro-particle transport and deposition
in a human oral airway model. Aerosol Science 33, 1635-1652.
Zhang Z. and Kleinstreuer C., 2003. Low-Reynolds-Number Turbulent Flows in Locally
Constricted Conduits: A Comparison Study. AIAA JOURNAL 41, 831-840.