Abstract：
OBJECTIVE: Adenoid hypertrophy causes impaired nasopharyngeal airways (NA) ventilation. However, it is difficult to evaluate the ventilatory conditions of NA. Therefore, this study aimed to analyze the nasopharyngeal airway resistance (NARES) based on computational fluid dynamics simulations and the nasopharyngeal airway depth (NAD) and adenoid hypertrophy grade measured on cephalometric cone-beam computed tomography images and determine the relationship between NAD and grade and NARES to ultimately assess using cephalometric measurements whether NA has airway obstruction defects.
METHODS: Cephalogram images were generated from cone-beam computed tomography data of 102 children (41 boys; mean age: 9.14 ± 1.43 years) who received orthodontic examinations at an orthodontic clinic from September 2012 to March 2023, and NAD and adenoid grade and NARES values were measured based on computational fluid dynamics analyses using a 3D NA model. Nonlinear regression analyses were used to evaluate the relationship between NARES and NAD and correlation coefficients to evaluate the relationship between grade and NARES.
RESULTS: NARES was inversely proportional to the cube of NAD (R2 = 0.786, P < 0.001), indicating a significant relationship between these variables. The resistance NARES increased substantially when the distance NAD was less than 5 mm. However, adenoid Grade 4 (75 % hypertrophy) was widely distributed.
CONCLUSIONS: These study findings demonstrate that the ventilatory conditions of NA can be determined based on a simple evaluation of cephalogram images. An NAD of less than 5 mm on cephalometric images results in NA obstruction with substantially increased airflow resistance.
METHODS: Cephalogram images were generated from cone-beam computed tomography data of 102 children (41 boys; mean age: 9.14 ± 1.43 years) who received orthodontic examinations at an orthodontic clinic from September 2012 to March 2023, and NAD and adenoid grade and NARES values were measured based on computational fluid dynamics analyses using a 3D NA model. Nonlinear regression analyses were used to evaluate the relationship between NARES and NAD and correlation coefficients to evaluate the relationship between grade and NARES.
RESULTS: NARES was inversely proportional to the cube of NAD (R2 = 0.786, P < 0.001), indicating a significant relationship between these variables. The resistance NARES increased substantially when the distance NAD was less than 5 mm. However, adenoid Grade 4 (75 % hypertrophy) was widely distributed.
CONCLUSIONS: These study findings demonstrate that the ventilatory conditions of NA can be determined based on a simple evaluation of cephalogram images. An NAD of less than 5 mm on cephalometric images results in NA obstruction with substantially increased airflow resistance.
摘要：
目的：腺样体肥大导致鼻咽气道（NA）通气受损。然而,很难评估NA的通气条件。因此,本研究旨在分析基于计算流体力学模拟的鼻咽气道阻力(NARES),以及在头颅测量锥形束计算机断层扫描图像上测量的鼻咽气道深度(NAD)和腺样体肥大分级,并确定NAD和分级与NARES之间的关系,以最终使用头颅测量评估NA是否存在气道阻塞缺陷.
方法：Cephalogram图像是根据2012年9月至2023年3月在正畸诊所接受正畸检查的102名儿童（41名男孩；平均年龄：9.14±1.43岁）的锥形束计算机断层扫描数据生成的，并使用3DNA模型基于计算流体动力学分析测量NAD和腺样体等级和NARES值。使用非线性回归分析来评估NARES与NAD之间的关系以及相关系数来评估等级与NARES之间的关系。
结果：NARES与NAD的立方成反比（R2=0.786，P<0.001），表明这些变量之间存在显著的关系。当距离NAD小于5mm时,电阻NARES显著增加。然而,腺样体4级(75%肥大)分布广泛。
结论：这些研究结果表明，NA的通气条件可以基于头影图像的简单评估来确定。头颅测量图像上小于5mm的NAD导致NA阻塞,具有显著增加的气流阻力。
方法：Cephalogram图像是根据2012年9月至2023年3月在正畸诊所接受正畸检查的102名儿童（41名男孩；平均年龄：9.14±1.43岁）的锥形束计算机断层扫描数据生成的，并使用3DNA模型基于计算流体动力学分析测量NAD和腺样体等级和NARES值。使用非线性回归分析来评估NARES与NAD之间的关系以及相关系数来评估等级与NARES之间的关系。
结果：NARES与NAD的立方成反比（R2=0.786，P<0.001），表明这些变量之间存在显著的关系。当距离NAD小于5mm时,电阻NARES显著增加。然而,腺样体4级(75%肥大)分布广泛。
结论：这些研究结果表明，NA的通气条件可以基于头影图像的简单评估来确定。头颅测量图像上小于5mm的NAD导致NA阻塞,具有显著增加的气流阻力。
