Duke University School of Medicine, Duke University Medical Center, Durham, North Carolina, U.S.A.
Department of Head and Neck Surgery and Communication Sciences, Duke University Medical Center, Durham, North Carolina, U.S.A.
Laryngoscope. 2023 Feb;133(2):366-374. doi: 10.1002/lary.30212. Epub 2022 May 24.
OBJECTIVES/HYPOTHESIS: Laryngotracheal stenosis (LTS) is a functionally devastating condition with high respiratory morbidity and mortality. This preliminary study investigates airflow dynamics and stenotic drug delivery in patients with one- and two-level LTS.
A Computational Modeling Restropective Cohort Study.
Computed tomography scans from seven LTS patients, five with one-level (three subglottic, two tracheal), and two with two-level (glottis + trachea, glottis + subglottis) were used to reconstruct patient-specific three-dimensional upper airway models. Airflow and orally inhaled drug particle transport were simulated using computational fluid dynamics modeling. Drug particle transport was simulated for 1-20 μm particles released into the mouth at velocities of 0 m/s, 1 m/s, 3 m/s, and 10 m/s for metered dose inhaler (MDI) and 0 m/s for dry powder inhaler (DPI) simulations. Airflow resistance and stenotic drug deposition in the patients' airway models were compared.
Overall, there was increased airflow resistance at stenotic sites in subjects with two-level versus one-level stenosis (0.136 Pa s/ml vs. 0.069 Pa s/ml averages). Subjects with two-level stenosis had greater particle deposition at sites of stenosis compared to subjects with one-level stenosis (average deposition 2.31% vs. 0.96%). One-level stenosis subjects, as well as one two-level stenosis subject, had the greatest deposition using MDI with a spacer (0 m/s): 2.59% and 4.34%, respectively. The second two-level stenosis subject had the greatest deposition using DPI (3.45%). Maximum deposition across all stenotic subtypes except one-level tracheal stenosis was achieved with particle sizes of 6-10 μm.
Our results suggest that patients with two-level LTS may experience a more constricted laryngotracheal airflow profile compared to patients with one-level LTS, which may enhance overall stenotic drug deposition.
NA Laryngoscope, 133:366-374, 2023.
目的/假设：喉气管狭窄（LTS）是一种功能破坏性疾病，具有较高的呼吸发病率和死亡率。本初步研究调查了一级和二级 LTS 患者的气流动力学和狭窄部位药物输送。
计算建模回顾性队列研究。
使用来自 7 名 LTS 患者的计算机断层扫描（CT）扫描，其中 5 名患者为一级狭窄（3 名声门下，2 名气管），2 名患者为二级狭窄（声门+气管，声门+声门下），重建患者特定的三维上气道模型。使用计算流体动力学建模模拟气流和口服吸入药物颗粒输送。对于 MDI，模拟以 0 m/s、1 m/s、3 m/s 和 10 m/s 的速度从口中释放 1-20 μm 颗粒的药物颗粒输送，而对于 DPI 模拟，速度为 0 m/s。比较患者气道模型中的气流阻力和狭窄部位药物沉积。
总体而言，与一级狭窄相比，二级狭窄患者狭窄部位的气流阻力增加（0.136 Pa s/ml 与 0.069 Pa s/ml 平均值）。与一级狭窄患者相比，二级狭窄患者在狭窄部位的颗粒沉积更多（平均沉积 2.31%与 0.96%）。一级狭窄患者以及一名二级狭窄患者使用带隔室的 MDI 时（0 m/s）具有最大的沉积：分别为 2.59%和 4.34%。第二位二级狭窄患者使用 DPI 时（3.45%）具有最大的沉积。除一级气管狭窄外，所有狭窄亚型的最大沉积均使用 6-10 μm 的颗粒尺寸实现。
我们的结果表明，与一级 LTS 患者相比，二级 LTS 患者的喉气管气流廓形可能更受限制，这可能会增强整体狭窄部位药物沉积。
无喉镜，133:366-374，2023 年。
