Department of Head and Neck Surgery & Communication Sciences, Duke University Medical Center, Durham, NC, USA.
Department of Head and Neck Surgery & Communication Sciences, Duke University Medical Center, Durham, NC, USA; Computational Biology & Bioinformatics PhD Program, Duke University, Durham, NC, USA; Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA.
Clin Biomech (Bristol). 2021 Feb;82:105282. doi: 10.1016/j.clinbiomech.2021.105282. Epub 2021 Jan 27.
The conductive mechanisms of olfaction are typically given little priority in the evaluation of olfactory function. The objective of this study is to investigate the role of nasal vestibule morphological variations on airflow volume at the olfactory recess in healthy subjects.
Anatomically realistic three-dimensional nasal airway models were constructed from computed tomography scans in five subjects. Each individual's unilateral nasal cavity (10 total) was classified according to the shape of their nasal vestibule: Standard, Notched, or Elongated. Nasal airflow simulations were performed using computational fluid dynamics modeling at two inspiratory flow rates (15 L/min and 30 L/min) to reflect resting and moderate breathing rates. Olfactory airflow volume and cross-sectional flow resistance were computed.
Average olfactory airflow volumes (and percent airflow in olfactory) were: 0.25 L/min to 0.64 L/min (3.0%-7.7%; 15 L/min simulations) and 0.53 L/min to 1.30 L/min (3.2%-7.8%; 30 L/min simulations) for Standard; 0.13 L/min - 0.47 L/min (2.0%-6.8%; 15 L/min simulations) and 0.06 L/min - 0.82 L/min (1.7%-6.1%; 30 L/min simulations) for Notched; and 0.07 L/min - 0.39 L/min (1.2%-5.4%; 15 L/min simulations) and 0.30 L/min - 0.99 L/min (2.1%-6.7%; 30 L/min simulations) for Elongated. On average, relative difference in olfactory resistance between left and right sides was 141.5% for patients with different unilateral phenotypes and 82.2% for patients with identical unilateral phenotype.
Olfactory cleft airflow volume was highest in the Standard nasal vestibule phenotype, followed by Notched phenotype for 15 L/min simulations and Elongated phenotype for 30 L/min simulations. Further, intra-patient variation in olfactory cleft airflow resistance differs greatly for patients with different unilateral phenotypes compared to patients with identical unilateral phenotype.
在评估嗅觉功能时，通常很少关注嗅觉传导机制。本研究旨在探究健康受试者中鼻前庭形态变化对嗅隐窝气流体积的作用。
从五名受试者的计算机断层扫描中构建了具有解剖学逼真度的三维鼻气道模型。根据鼻前庭的形状将每个人的单侧鼻腔（共 10 个）分类：标准型、切迹型或伸长型。使用计算流体动力学模型在两个吸气流量（15 L/min 和 30 L/min）下进行鼻气流模拟，以反映静息和中等呼吸率。计算了嗅觉气流体积和横截面积流阻。
标准型的平均嗅觉气流体积（和嗅觉气流百分比）为 0.25 L/min 至 0.64 L/min（3.0%-7.7%；15 L/min 模拟）和 0.53 L/min 至 1.30 L/min（3.2%-7.8%；30 L/min 模拟）；切迹型为 0.13 L/min 至 0.47 L/min（2.0%-6.8%；15 L/min 模拟）和 0.06 L/min 至 0.82 L/min（1.7%-6.1%；30 L/min 模拟）；伸长型为 0.07 L/min 至 0.39 L/min（1.2%-5.4%；15 L/min 模拟）和 0.30 L/min 至 0.99 L/min（2.1%-6.7%；30 L/min 模拟）。平均而言，左右两侧嗅觉阻力的差异在单侧表型不同的患者中为 141.5%，在单侧表型相同的患者中为 82.2%。
标准鼻前庭表型的嗅隐窝气流体积最大，15 L/min 模拟时为切迹型，30 L/min 模拟时为伸长型。此外，单侧表型不同的患者嗅隐窝气流阻力的个体内差异明显大于单侧表型相同的患者。
