经鼻内镜前颅底肿瘤切除术后鼻腔结构改变对鼻气流与温湿度影响的数值模拟研究

Impact of sinonasal anatomic changes after endoscopic anterior skull base surgery on nasal airflow and air conditioning:a computational fluid dynamics study

目的通过计算机数值模拟,分析前颅底肿瘤患者经鼻内镜术后鼻腔结构改变对经鼻气流与鼻腔加温加湿功能的影响,探讨术后气流动力学及温湿度参数与患者主观症状的相关性。方法回顾性选择2016—2021年于郑州大学第一附属医院鼻科行鼻内镜手术的前颅底肿瘤患者为病例组,选择同期鼻腔鼻窦CT无明显异常的成年人为对照组。将病例组术后随访期间的鼻窦CT影像重建后进行计算机数值模拟,分析术后鼻腔气流动力学及温湿度参数改变。所有患者随访时填写《空鼻综合征6项问卷》(Empty Nose Syndrome 6 Item Questionnaires,ENS6Q)评估主观症状。应用SPSS 26.0软件,采用Mann-Whitney U检验进行各参数的组间比较,Spearman秩相关分析考察相关性。结果共有病例组19例患者(男性8例,女性11例;年龄22~67岁)和2名对照(男女各1名,年龄分别为38岁和45岁)入选本研究。前颅底术后高速气流向鼻腔上部偏移,后鼻孔处最低气温区域上移。与对照组相比,病例组的鼻腔黏膜表面积-鼻腔通气容积比[M(P25,P75),下同]减小[0.41(0.40,0.41)mm^(-1)比0.32(0.30,0.38)mm^(-1);Z=-2.04,P=0.041];鼻腔中上部的气流流量增高[61.14(59.78,62.51)%比78.07(76.22,94.43)%;Z=-2.28,P=0.023];鼻阻力降低[0.024(0.022,0.026)Pa·s/ml比0.016(0.009,0.018)Pa·s/ml;Z=-2.29,P=0.022];鼻腔中部最低气温降低[28.29(27.23,29.35)℃比25.06(24.07,25.50)℃;Z=-2.28,P=0.023];鼻腔加温效率降低[98.74(97.95,99.52)%比82.16(80.24,86.91)%;Z=-2.28,P=0.023];最低相对湿度降低[79.62(76.55,82.69)%比73.28(71.27,75.05)%;Z=-2.28,P=0.023];鼻腔加湿效率降低[99.50(97.69,101.30)%比86.09(79.33,87.16)%;Z=-2.28,P=0.023]。病例组所有患者ENS6Q总评分<11分;术后鼻腔下部气流占比和ENS6Q总分之间存在中等程度的负相关性(rs=-0.50,P=0.029)。结论前颅底肿瘤内镜术后鼻腔结构的改变会导致经鼻气流模式变化,降低鼻腔加温加湿效率,但术后发生空鼻综合征的倾向较小。

Objective To analyze the impact of the sinonasal anatomic changes after endonasal endoscopic anterior skull base surgery on the nasal airflow and heating and humidification by computational fluid dynamics(CFD),and to explore the correlation between the postoperative CFD parameters and the subjective symptoms of the patients.Methods The clinical data in the Rhinology Department of the First Affiliated Hospital of Zhengzhou University from 2016 to 2021 were retrospectively analyzed.The patients received the endoscopic resection of the anterior skull base tumor were selected as the case group,and the adults whose CT scans had no sinonasal abnormalities were chosen as the control group.The CFD simulation was performed on the sinonasal models after reconstructed from the patients′sinus CT images during the post-surgical follow-up.All the patients were asked to complete the Empty Nose Syndrome 6-Item Questionnaire(ENS6Q)to assess the subjective symptoms.The comparison between two independent groups and the correlation analysis were carried out by using the Mann-Whitney U test and the Spearman correlation test in the SPSS 26.0 software.Results Nineteen patients(including 8 males and 11 females,from 22 to 67 years old)in the case group and 2 patients(a male of 38 years old and a female of 45 years old)in the control group were enrolled in this study.After the anterior skull base surgery,the high-speed airflow moved to the upper part of the nasal cavity,and the lowest temperature shifted upwards on the choana.Comparing with the control group,the ratio of nasal mucosal surface area to nasal ventilation volume in the case group decreased[0.41(0.40,0.41)mm-1vs 0.32(0.30,0.38)mm-1;Z=-2.04,P=0.041],the air flow in the upper and middle part of the nasal cavity increased[61.14(59.78,62.51)%vs 78.07(76.22,94.43)%;Z=-2.28,P=0.023],the nasal resistance decreased[0.024(0.022,0.026)Pa·s/ml vs 0.016(0.009,0.018)Pa·s/ml;Z=-2.29,P=0.022],the lowest temperature in the middle of the nasal cavity decreased[28.29(27.23,29.35)℃vs 25.06(24.07,25.50)℃;Z=-2.28,P=0.023],the nasal heating efficiency decreased[98.74(97.95,99.52)%vs 82.16(80.24,86.91)%;Z=-2.28,P=0.023],the lowest relative humidity decreased[(79.62(76.55,82.69)%vs 73.28(71.27,75.05)%;Z=-2.28,P=0.023],and the nasal humidification efficiency decreased[99.50(97.69,101.30)%vs 86.09(79.33,87.16)%;Z=-2.28,P=0.023].The ENS6Q total scores of all patients in the case group were less than 11 points.There was a moderate negative correlation between the proportion of the inferior airflow in the post-surgical nasal cavity negatively and the ENS6Q total scores(rs=-0.50,P=0.029).Conclusions The sinonasal anatomic changes after the endoscopic anterior skull base surgery alter the nasal airflow patterns,reducing the efficiency of nasal heating and humidification.However,the post-surgical occurrence tendency of the empty nose syndrome is weak.