Morphological Study Of Upper Airway In Patients With Obstructive Sleep Apnea Based On Ultrasonography And Evaluation Of Its Combined Prediction And Diagnosis Of OSA

Background:Obstructive Sleep Apnea（OSA）is a condition in which patients experience repeated and frequent upper airway obstruction,either incomplete or complete,during the night at sleep,with corresponding hypoventilation or apnea,which causes the patient to wake up repeatedly from sleep.Obstruction,collapse,and stenosis caused by abnormal upper airway anatomy are important factors in the pathogenesis of OSA.The main methods of upper airway morphological examination include laryngoscopy,CT,MR,etc.However,laryngoscopy lacks quantitative methods and has poor effect on the evaluation of surgical prognosis.CT,MR,etc.are the main quantitative methods,but there are radiation and high costs.The problem is that ultrasonography has the advantages of being easy to operate and portable,but the research on the application of ultrasonography in the upper airway of patients with obstructive sleep apnea is still insufficient.Therefore,the anatomical structure of the upper airway in patients with OSA was measured by ultrasound,and its correlation with OSA and its diagnostic research were analyzed.In addition,In addition,we also explored the value of the upper airway structural indicators measured by ultrasound combined with BMI,Epworth questionnaire and STOP-Bang questionnaire in the diagnosis of OSA.This will be of great significance in screening OSA patients in primary hospitals.Objective:To investigate the difference of upper airway morphology between OSA subjects and non-OSA subjects based on ultrasound measurement,and analyze and compare the predictive power of ultrasound examination and traditional scales in the diagnosis of OSA.Method:1.OSA subjects（OSA group）and non-OSA subjects（non-OSA group）in Shenzhen Second People’s Hospital from January 2021 to January 2022 were randomly recruited,and performed upper airway ultrasonography to measure upper air.The anatomical parameters were compared and analyzed between the two groups.The Spearman correlation analysis was performed on the ultrasound measurements of OSA patients with apnea-hypopnea index（AHI）and lowest oxygen saturation（LSa O2）;2.Find the cut-off value of the upper airway difference index（p<0.05）measured by ultrasound between OSA subjects and non-OSA subjects;3.The STOP-Bang questionnaire and Epworth sleepiness scale scores of OSA subjects and non-OSA subjects were counted,and the STOP-Bang questionnaire score≥3 points and the Epworth sleepiness scale score≥9 points were divided into high-risk groups;4.To compare the efficacy of ultrasound,STOP-Bang questionnaire and Epworth sleepiness scale in diagnosing OSA.Finally,a predictive model was constructed to compare the diagnostic efficacy of the predictive model with ultrasound measurement indicators,BMI,STOP-Bang questionnaire and Epworth sleepiness scale.Result:1.There were significant differences in BMI,the distance from the junction of the soft and hard palate to the hyoid bone,the angle between the hard palate and the soft palate,and the angle between the hyoid and the hard palate between the OSA group and the non-OSA group（all p<0.001）.Correlation analysis was carried out between the measured values of airway B-ultrasound and AHI and LSa O2.The results showed that the distance from the junction of the soft and hard palate to the mandible,the distance from the junction of the soft and hard palate to the hyoid,the thickness of the tongue（longitudinal section）,the thickness of the soft palate（longitudinal section）were related to AHI There was a positive correlation（r=0.3758,0.4619,0.3227,0.2738,P<0.05）;the distance from the junction of the soft and hard palate to the mandible,the distance from the junction of the soft and hard palate to the hyoid,and the thickness of the tongue（longitudinal section）were negatively correlated with LSa O2（r=-0.3566,-0.5470,-0.3168,-0.3098,p<0.05）;the angle between the hard palate and the soft palate was negatively correlated with AHI（r=-0.2262,p<0.05）;the angle between the hyoid and the hard palate was positively correlated with AHI,was negatively correlated with LSa O2（r=0.2889,-0.3351,p<0.01）.2.The distance from the junction of the soft and hard palate to the hyoid bone had the best correlation with LSa O2（r=-0.5470,p<0.05）,which indicated that the more backward and downward the hyoid bone was relative to the hard palate,the more severe the OSA patients were.3.Tongue width（transverse section）,the distance from the junction of the soft and hard palate to the hyoid bone,and the cut-off values of the angle formed by the two axes of the hard palate and the soft palate were 42.10mm,26.10Kg/m~2,and 154°,respectively.4.The angle formed by the two axes of the hard palate and the soft palate is defined as the width of the tongue（cross section）,BMI≥26Kg/m~2,the width of the tongue（cross section）≥42.10mm,the distance from the junction of the soft and hard palate to the hyoid bone is≥26.10Kg/m~2.The AUC of the predictive model constructed with a cutoff value of≤154°was 0.898（0.844-0.951）,the sensitivity was 0.762,and the specificity was high（0.944）.5.When screening for obstructive sleep apnea,compared with the STOP-Bang questionnaire and the Epworth sleepiness scale,the specificity and accuracy of the ultrasound indicators were the highest,0.853 and 0.875,respectively;the sensitivity of the STOP-Bang questionnaire was the best,is 0.895.6.In the combined prediction model of SBQ,ESS and BMI to predict and diagnose OSA,the sensitivity of SBQ+ESS was the highest（0.896）,the specificity of SBQ+ESS+BMI was the highest（0.882）,and the area under the curve of SBQ+ESS+BMI was the highest,which AUC was 0.886（0.811-0.961）.7.When screening for obstructive sleep apnea,the combined prediction model of ultrasound index+STOP-Bang questionnaire+BMI is better,with AUC of 0.953（0.910～0.995）.Conclusion:The anatomical parameters of the upper airway based on ultrasound measurement,such as the distance from the junction of the soft and hard palate to the mandible,the distance from the junction of the soft and hard palate to the hyoid,the angle between the hyoid bone and the hard palate,and the angle between the hard palate and the soft palate,etc.There are differences between patients,and it is related to the severity of disease in patients with OSA,and can be used as an objective indicator to assess the severity of disease in patients with OSA.The diagnostic prediction model established by ultrasound indicators（tongue width（transverse section）,the angle formed by the two axes of the hard palate and the soft palate,the distance from the junction of the soft and hard palate to the hyoid bone）combined with BMI has good predictive performance;they can represent the upper airway.The anatomical structure of different levels and the patient’s baseline situation are consistent with the pathogenesis of the anatomical structure of the upper airway abnormality in OSA patients,and the predictive model constructed by combining with the STOP-Bang questionnaire can further improve the sensitivity and specificity of its diagnosis.This would be a potential alternative to primary screening for OSA.