Flow Analysis in Upper Airway for an OSA Subject Before and After Surgery

Obstructive sleep apnea (OSA) is very common and can strike anyone at any age, even children. Yet still because of the lack of awareness by the public and healthcare professionals, the majority remain undiagnosed and therefore untreated, despite the fact that this serious disorder can have significant consequences. Untreated, sleep apnea can cause high blood pressure and other cardiovascular disease, memory problems, weight gain, impotency, and headaches [1]. OSA is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses and closes during sleep. With apnea event, the brain briefly arouses people with sleep apnea in order for them to resume breathing, but consequently sleep is extremely fragmented and of poor quality. Several surgical techniques may be used for OSA, and these include: uvulopalatopharngeoplasty (UP3), tonsillectomy and pharyngoplasty, uvulopalatal flap, laser and radiofrequency assisted uvulopalatal surgeries. The surgery involves removing the uvula and some of the surrounding soft palate. The idea behind the upper airway surgery is to eliminate the area of obstruction or to widen the airway so it does not occlude completely. However, the success rate is limited; for example, the UP3 helps in around 50% who have the surgery and in others it does not help at all or it helps only partially [2]. The post-operative complications after surgery are often the result of a dilemma during the operation of how much tissue to resect: too little is ineffective, yet too much may leave a patient with speech impedance and palatal stenosis, which can make OSA worse [3]. Therefore, accurate prediction of tissue reduction for this treatment is urgently needed.Copyright © 2011 by ASME