Maxillary sinus aeration analysis using computational fluid dynamics

Abstract

The maxillary sinus aeration using the computational fluid dynamics (CFD) method based on individual adult patients’ computed tomography (CT) scans were analyzed. The analysis was based on CT images of 4 patients: one with normal nose anatomy and three with nasal septal deviation (NSD) and concha bullosa (CB). The CFD simulation was performed using the Reynolds-Average Simulation approach and turbulence closure based on linear eddy viscosity supplemented with the two-equation k-$$\omega$$ ω SST model. As a result, it was found that the lower part of NSD has the most significant impact on the airflow change within the maxillary sinuses compared to CB and the upper part of NSD. In a healthy nose, the airflow in the sinuses is continuous, while NSD and CB change this flow into pulsatile. Multiple changes in the direction of flow during one respiratory phase were observed. The flow intensity within the maxillary sinus opening is lower on the NSD side. The concept of vorticity measure is introduced to evaluate and compare various patients qualitatively. Typically, the lowest values of such measures are obtained for healthy airways and the highest for pathological changes in the nasal cavity.

The anatomical variations of paranasal sinuses may be related to the formation of antrochoanal polyp by computed tomography imaging study

“…Li et al also noted that there were significant differences in maximum airflow velocity, minimal airflow temperature, maximum wall shear stress, and nasal resistance between the deviated side (the narrow side of the nasal meatus) and the nondeviated side of the nasal septum in their hydrodynamic analysis of patients with nasal septum deviation ( 27 ). Tretiakow et al said that the complex nasal meatus structure caused by anatomic variations would change continuous airflow in the healthy nasal cavity so that it becomes volatile ( 28 ). The findings of Li et al revealed a positive correlation between the change in nasal volume and nasal airflow ( 27 ), which also supported our hypothesis that the change of nasal airflow is related to ACP formation.…”

Numerical analysis of the ostiomeatal complex aeration using the CFD method

“…The study of the influence of the mesh on the solution was presented in our previous publication 28 . Moreover, the properties of the mesh and calculation times (Xeon 5120 2.2 GHz processor (13 out of 14 cores involved)) are given in Table 2.…”

“…The inlet boundary condition localised at the larynx was specified through the volumetric flow rate corresponding to 5.1 litres per minute 9,28 . It was assumed that the typical breath took 4 seconds and that the exhalation and inhalation phases each lasted 2 seconds.…”

“…The averaged values are understood as the integral average over time t of an integral average over flow volume V, i.e. 28,29 The lower subscript e indicates the exhalation phase and i -the inhalation phase.…”