鼻中隔偏曲者鼻腔结构自适应改变的特征分析

目的 对10例鼻中隔偏曲者及20例健康北方人的鼻腔结构进行三维重建,将二者气流流场进行数值模拟,分析二者鼻腔气道气流流场特征,探讨其与鼻腔结构和功能之间的关系.方法 根据10例鼻中隔偏曲者和20例健康人的鼻腔CT影像,应用表面重建的方法对鼻腔气道进行三维重建,用有限元法对气流进行数值模拟,分析二者鼻腔气道气流流场特征.结果 从模拟的速度云图得出鼻中隔偏曲者通过双侧鼻腔的气流量以气道宽敞侧鼻腔为主,以总鼻道中部最为明显.健康人鼻腔气流量以一侧鼻腔为主,以总鼻道中部、总鼻道下部为明显.从模拟的压强云图得出鼻中隔偏曲者在鼻中隔偏曲最为明显处气压下降最快,占气道总压强差值的71.36%;健康人于鼻阈处气压下降最快,占气道总压强差值的58.78%.鼻中隔偏曲者鼻腔气道阻力较健康人增大.结论 数字化三维重建鼻腔气道模型可反映鼻腔气流通道的基本特征,可用于分析因鼻腔解剖结构异常而导致的鼻腔空气动力学特征改变,本实验初步证明鼻腔结构自适应功能的存在,为鼻腔自适应模型的建立打下基础.

Analysis of the character of self-adaptation of nasal structure in patients with nasal septum deviation

OBJECTIVE: To analyze the different characters of nasal airflow-field between 10 patients with nasal septum deviation and 20 healthy Chinese people by the method of three-dimensional reconstruction of these people's nasal cavity and numerical simulation of the flow field in these nasal cavity models. The character of airflow-field was considered by analyzing the relationship between the structure and function of the human nose. METHODS: Based on the data obtained from the CT images, 10 patients with nasal septum deviation and 20 healthy Chinese people's nasal cavity models were reconstructed by the method of surface rendering. The flow field in these three-dimensional models was simulated with finite element method. The different characters of nasal airflow-field was analysed between two groups of people. RESULTS: The airflow distribution in the nasal cavity model could be acquired from the simulation results of the velocity. The airflow for patients with nasal septum deviation mainly passed through the broad nasal cavity, especially in the middle part of meatus of nose. In the healthy people group, the airflow mainly passed through the main side of the nasal cavity, especially in the middle and inferior part of the meatus of nose. The pressure value at any point in the nasal cavity model could be obtained from the results of the pressure plot. In the patients with nasal septum deviation, the pressure mainly dropped in the part of the nasal septum deviation, accounting approximately 71.36% of the total pressure drop. In the group of healthy people, the pressure dropped mainly in the limen nasi, accounting approximately 58.78% of the total pressure drop. The nasal airway resistance of the patients with nasal septum deviation was larger than that in the group of healthy people. CONCLUSIONS: The three-dimensional nasal airway can reflect the characters of the human nasal airway. It can be used to analyze the change of the aerodynamic in nasal cavity caused by the abnormal anatomy of the nose. This experiment can proof that human nose has the function of self-adaptation, it can build a foundation for the construction of the model of self-adaptation of the human nose.