Model of upper airway flow restriction in children with obstructive sleep APNEA

Obstructive sleep apnea syndrome (OSAS) in children is correlated to anatomy of the upper airway. Segmented magnetic resonance images of airways from ten OSAS and ten matched control children were used to generate computer flow models. Steady turbulent axisymmetric flow models were solved at peak flow rate to estimate the effect of restricted airway area on pressure drop and resistance. OSAS patients had significantly higher pressure drop and resistance than controls. The magnitude of pressure drop was similar to reported critical airway closure pressures. A subset of OSAS patients had pressure drop and flow resistance similar to controls. Flow modeling may be a useful method to assess the role of anatomy in OSAS.