Application of computational fluid dynamics for the analysis of postoperative airway changes in oral cancer patients

To analyze airway changes in patients who underwent various types of oral cancer surgery, computational fluid dynamics (CFD) based on 3D reconstruction of the airway was applied. Seventeen patients were included in the study (12 males and 5 females). The mean age was 57.1 years (range 22–78). They showed the highest rate of T2 stage. In neck dissection (ND) performed with the removal of the primary lesion, selective ND had the highest rate (58.2%). The anterolateral thigh (ALT) flap was the most commonly used for reconstruction after the malignant lesion was removed (52.9%). The airways of the patients were remodeled using computed tomographic data, and CFD was applied to the model. The CFD results showed that 47.1% (n = 8) of patients showed deterioration of airway airflow, 23.5% (n = 4) of patients had rapid deterioration, and 29.4% (n = 5) of patients showed remission. The sex and age of the patient, the location and size of the primary lesion, and the type of surgery performed were not significantly correlated with changes in the airway flow rate. A significant reduction in cross-sectional area with a reduction in volume can promote high velocity, resulting in a high-pressure drop to ensure the same flow rate of inhaled air. An increase in volume with reduced height can attenuate undesirable flow and reduce pressure drop in the case of airflow alleviation.