Numerical Simulation Of Nasal Septum Deviation With Spinous Process Flow

Objective:This paper Establishes nasal cavity CFD model through the CT scan data of nasal cavity in patients with deviated nasal septum and analysis by numerical simulation of the nasal cavity flow field, determines the relationship with the symptoms of nasal congestion by observed the influence of the nasal septum spinous process on the airflow.Methods:This paper uses a visual analog scale score (VAS) from36cases of patients with deviated nasal septum spinous process to evaluate the severity of the symptoms of nasal congestion.Continuous thin layer scanning on nasal is made by Using16-slice spiral CT on the spinous process in patients with36cases of nasal septum deviation and30cases of normal people. The nasal cavity three-dimensional model is developed by importing the CT scan data to the medical image reconstruction software (Mimics) and then converted to CFD model. The nasal cavity airflow is simulated and reproduced by the computer fluid mechanics software (Fluent) on the conditions of the tidal volume400ml.Results:Experiments show that VAS score about36cases of nasal septum deviation the spinous patients is7.47±1.62, the flow rates of inspiratory and expiratory peak are8.1±1.52m/s and-6.7±0.45m/s in the nasal septum spinous process by Fluent simulating on the conditions of the tidal volume400ml.In addition, the pressure changes significantly near spinous process, increases in front of the spinous process and reduces behind it when inspiratory. The reverse results appear when expiratory. Correlation analysis of the Spearman rank is made through VAS, flow peak rate of inspiratory and expiratory, airflow rate and pressure around the nasal septum spinous process, distance from the spinous process to the anterior nasal spine. Results show that VAS and the parameters have no significant correlationConclusion:The nasal CFD mode is successfully established on the36cases of patients with nasal septum deviation and30cases of normal people. The validity of the analysis of the CFD model is verified by compared the simulated results with the previous literature.The respiratory airflow distribution of patients with nasal septum deviation is different from that of normal people. The spinous process impedes the normal air flow, changes the traffic distribution near it, impacts pressure distribution within the nasal cavity. But the flow rate, pressure changes and symptoms of nasal congestion was no significant correlation.