Department of Medical Imaging and Physiology, Skåne University Hospital, Malmö, Sweden.
Department of Translational Medicine, Lund University, Malmö, Sweden.
Int J Nanomedicine. 2018 May 21;13:2989-2995. doi: 10.2147/IJN.S160331. eCollection 2018.
Airspace Dimension Assessment with inhaled nanoparticles is a novel method to determine distal airway morphology. This is the first empirical study using Airspace Dimension Assessment with nanoparticles (AiDA) to estimate distal airspace radius. The technology is relatively simple and potentially accessible in clinical outpatient settings.
Nineteen never-smoking volunteers performed nanoparticle inhalation tests at multiple breath-hold times, and the difference in nanoparticle concentration of inhaled and exhaled gas was measured. An exponential decay curve was fitted to the concentration of recovered nanoparticles, and airspace dimensions were assessed from the half-life of the decay. Pulmonary tissue density was measured using magnetic resonance imaging (MRI).
The distal airspace radius measured by AiDA correlated with lung tissue density as measured by MRI ( = -0.584; = 0.0086). The linear intercept of the logarithm of the exponential decay curve correlated with forced expiratory volume in one second (FEV) ( = 0.549; = 0.0149).
The AiDA method shows potential to be developed into a tool to assess conditions involving changes in distal airways, eg, emphysema. The intercept may reflect airway properties; this finding should be further investigated.
吸入纳米颗粒的空域尺寸评估是一种用于确定远端气道形态的新方法。这是首次使用纳米颗粒空域尺寸评估（AiDA）来估计远端气道半径的实证研究。该技术相对简单，在临床门诊环境中具有潜在的应用前景。
19 名从不吸烟的志愿者在多个屏气时间进行纳米颗粒吸入测试，并测量吸入和呼出气体中纳米颗粒浓度的差异。对回收纳米颗粒的浓度进行指数衰减曲线拟合，并从衰减的半衰期评估空域尺寸。使用磁共振成像（MRI）测量肺组织密度。
AiDA 测量的远端气道半径与 MRI 测量的肺组织密度呈负相关（ = -0.584； = 0.0086）。指数衰减曲线的对数线性截距与一秒用力呼气量（FEV）呈正相关（ = 0.549； = 0.0149）。
AiDA 方法显示出有望发展成为评估涉及远端气道变化的情况（例如肺气肿）的工具的潜力。截距可能反映气道特性；这一发现需要进一步研究。
