| As the portal organ of the respiratory system,the nasal cavity can fully warm,humidify,filter,and vaccinate the air flow that enters the nasal cavity.Among them,the respiratory and warming functions are the two most important biological functions.Whether the nasal airway structure is normal or not determines whether it can maintain normal physiological functions.As the current mainstream nasal surgery technology,the core idea of functional endoscopic sinus surgery is to rectify the pathological airway structure,restore the normal ventilation and drainage of the nasal cavity,and create conditions for the "self healing" of the nasal cavity.Modern precision medicine has put forward higher requirements and challenges in the field of rhinology,and it is necessary to further study the relationship between nasal structure-function-disease.Previous experimental studies and animal models have not fully met the basic and clinical research needs of modern rhinology.As a new research method,biological numerical simulation,combined with traditional experiments,can not only make up the above shortcomings,but also provide support for the objective quantitative research between the structure,function and disease of the nasal cavity,and can provide impetus for the development of rhinology.The briefing of the 174th Colloquium of the Xiangshan Science Conference pointed out:"At present,human beings have not enough knowledge and understanding of themselves,research on causes,diagnosis and treatment of disease,and research on complex interactions between the human body and the environment and so on are limited by the lack of an accurate Numerical model of biological function " The numerical simulation of nasal airway is limited due to the lack of biological and computational models with Chinese nasal cavity characteristics,which affects further understanding of the dialectical relationship between nasal structure-function-disease,and it is difficult to meet the needs of the formulation of personalized operation scheme and postoperative evaluation.In this paper,the most important functions of respiration and warming were selected to conduct numerical simulation.Furthermore,two common diseases,such as nasal septum deviation and nasal septum perforation were selected to study the pathogenesis of nasal respiratory dysfunction caused by abnormal nasal airway structures;Combined with clinical tests,the confusion of whether the nasal cycle affects the function of bilateral nasal heating has been studied;There is a "adaptive change" characteristic of the nasal airway,which is closely related to the pathogenesis of nasal cavity disease,but its mechanism is not clear so far.Through multi-level research,this article revealed the physical environment changes in the nasal cavity lead to airway structure remodeling and its pathogenesis mechanism.The work of this paper is divided into five parts:1.The method of establishing the numerical model of nasal cavity:On basis of the two-dimensional anatomical data of the nasal cavity of the Chinese people through CT,the finite element model that reflects characteristics of nasal airway was established and numerically simulation of the nasal airflow and temperature fields was processed.Compared with the literature reports,the accuracy of the model was judged.2.Numerical simulation of the effect of nasal septum perforation on nasal airflow field:nasal septum perforation is a typical nasal airway disorder with various clinical manifestations and its mechanism is unknown.Based on the clinical data,the numerical model of nasal airway was used to simulate the establishment of nasal septum perforation at different sites and diameters and the effect of perforations on nasal respiratory function were evaluated.It was found that the local airflow pattern was disordered and there was a phenomenon of "flow diversion" between bilateral nasal airway.The pathogenesis of nasal septum perforation was explained from a biomechanical point of view.3.Numerical simulation of the warming function of nasal cavity in healthy Chinese:numerical simulation of the distribution characteristics of the airflow and temperature field in the nasal cavity under different ventilation conditions,study the characteristics of the warming function of the nasal cavity and the effect of ventilation on it.and find that nasal valve is the main part of the nasal cavity to warm the airstream,which suggests that the operation should be minimally invasive and individualized to restore and protect the physiological function of the nasal cavity.4.Effect of nasal cycle on heating function of nasal cavity:nasal cycle is the important physiological function of the nasal cavity.The periodic contraction and expansion of the submucous vessels are the basic characteristics,and the bilateral nasal airway volume,airway resistance and ventilation volume also occur periodically and alternately.Does nasal heating function change as a result of nasal cycle?So far it has been a nuisance to rhinology.In this paper,the experiment of nasal acoustic rihnometry and temperature measurement were carried out.The characteristics of the airflow field and temperature field in the nasal airway were studied by numerical simulation.It was found that the warming function of bilateral nasal cavity did not change because of the volume change of the airway.It indicates that the nasal cycle does not affect the warming function of bilateral nasal airway.5.The pathogenesis of adaptive changes in nasal airway in patients with deviated septum:nasal airway structural changes will lead to secondary "adaptive" remodeling of the airway,and nasal septum deviation is a typical representative of this type of disease.This feature is also related to the pathogenesis of many nasal diseases,but its mechanism is still unknown.Numerical simulation study found that the respiratory dysfunction caused by nasal septum deviation was mainly manifested by the obvious difference in the airflow field of bilateral nasal cavity.The histological study found that the number and function of the cells in the inferior turbinate and intracellular organelles in the bilateral nasal turbinate were different.It was found that the expression of VIP and SP neuropeptides in bilateral inferior turbinate was increased and they were characterized by differences in distribution.The results showed that the hypoventilation of patients with deviated septum was shown to be macroscopically and microscopically altered through neuropathic inflammation,that is self-adaptive change,which reveals the pathogenesis of the remodeling of the airway in the nasal cavity,and provides a new way for the research of the nasal precision medicine.This study originated from clinical practice,and the results could provide quantitative guidance for the explaination of the pathogenesis of nasal diseases,the formulation of personalized diagnosis and treatment scheme and the assessment of postoperative efficacy. |
PDF Full Text Request