Kwang K Chang1, Ki Beom Kim2, Mark W McQuilling3, Reza Movahed4. 1. Center for Advanced Dental Education, Saint Louis University, St. Louis, Mo. Electronic address: kkcman@gmail.com. 2. Center for Advanced Dental Education, Saint Louis University, St. Louis, Mo. 3. College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Mo. 4. Center for Advanced Dental Education, Saint Louis University, St. Louis, Mo; private practice, St. Louis, Mo.
Abstract
INTRODUCTION: The purpose of this study was to analyze pharyngeal airflow using both computational fluid dynamics (CFD) and fluid structure interactions (FSI) in obstructive sleep apnea patients before and after maxillomandibular advancement (MMA) surgery. The airflow characteristics before and after surgery were compared with both CFD and FSI. In addition, the presurgery and postsurgery deformations of the airway were evaluated using FSI. METHODS: Digitized pharyngeal airway models of 2 obstructive sleep apnea patients were generated from cone-beam computed tomography scans before and after MMA surgery. CFD and FSI were used to evaluate the pharyngeal airflow at a maximum inspiration rate of 166 ml per second. Standard steady-state numeric formulations were used for airflow simulations. RESULTS: Airway volume increased, pressure drop decreased, maximum airflow velocity decreased, and airway resistance dropped for both patients after the MMA surgery. These findings occurred in both the CFD and FSI simulations. The FSI simulations showed an area of marked airway deformation in both patients before surgery, but this deformation was negligible after surgery for both patients. CONCLUSIONS: Both CFD and FSI simulations produced airflow results that indicated less effort was needed to breathe after MMA surgery. The FSI simulations demonstrated a substantial decrease in airway deformation after surgery. These beneficial changes positively correlated with the large improvements in polysomnography outcomes after MMA surgery.
INTRODUCTION: The purpose of this study was to analyze pharyngeal airflow using both computational fluid dynamics (CFD) and fluid structure interactions (FSI) in obstructive sleep apneapatients before and after maxillomandibular advancement (MMA) surgery. The airflow characteristics before and after surgery were compared with both CFD and FSI. In addition, the presurgery and postsurgery deformations of the airway were evaluated using FSI. METHODS: Digitized pharyngeal airway models of 2 obstructive sleep apneapatients were generated from cone-beam computed tomography scans before and after MMA surgery. CFD and FSI were used to evaluate the pharyngeal airflow at a maximum inspiration rate of 166 ml per second. Standard steady-state numeric formulations were used for airflow simulations. RESULTS: Airway volume increased, pressure drop decreased, maximum airflow velocity decreased, and airway resistance dropped for both patients after the MMA surgery. These findings occurred in both the CFD and FSI simulations. The FSI simulations showed an area of marked airway deformation in both patients before surgery, but this deformation was negligible after surgery for both patients. CONCLUSIONS: Both CFD and FSI simulations produced airflow results that indicated less effort was needed to breathe after MMA surgery. The FSI simulations demonstrated a substantial decrease in airway deformation after surgery. These beneficial changes positively correlated with the large improvements in polysomnography outcomes after MMA surgery.
Authors: Hussein Aljawad; Mario Rüttgers; Andreas Lintermann; Wolfgang Schroöder; Kyungmin Clara Lee Journal: J Digit Imaging Date: 2021-09-10 Impact factor: 4.903
Authors: W M Faizal; N N N Ghazali; C Y Khor; Irfan Anjum Badruddin; M Z Zainon; Aznijar Ahmad Yazid; Norliza Binti Ibrahim; Roziana Mohd Razi Journal: Comput Methods Programs Biomed Date: 2020-06-26 Impact factor: 5.428