What Causes Uneven Aerosol Deposition in the Bronchoconstricted Lung? A Quantitative Imaging Study
| Autor: | Jose G. Venegas, Tilo Winkler, Ira Katz, Vanessa J. Kelly, R. S. Harris, Mamary Kone, Elliot Greenblatt, George Caillibotte, Andrew R. Martin |
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| Rok vydání: | 2016 |
| Předmět: |
Pulmonary and Respiratory Medicine
Quantitative imaging Lung Meteorology Respiratory rate Chemistry 0206 medical engineering Pharmaceutical Science Imaging study 02 engineering and technology respiratory system Atmospheric sciences 020601 biomedical engineering Aerosol 03 medical and health sciences 0302 clinical medicine Deposition (aerosol physics) medicine.anatomical_structure 030228 respiratory system Aerosol deposition Breathing medicine Pharmacology (medical) Original Research |
| Zdroj: | Journal of Aerosol Medicine and Pulmonary Drug Delivery. 29:57-75 |
| ISSN: | 1941-2703 1941-2711 |
| Popis: | A previous PET-CT imaging study of 14 bronchoconstricted asthmatic subjects showed that peripheral aerosol deposition was highly variable among subjects and lobes. The aim of this work was to identify and quantify factors responsible for this variability.A theoretical framework was formulated to integrate four factors affecting aerosol deposition: differences in ventilation, in how air vs. aerosol distribute at each bifurcation, in the fraction of aerosol escaping feeding airways, and in the fraction of aerosol reaching the periphery that is exhaled. These factors were quantified in 12 of the subjects using PET-CT measurements of relative specific deposition sD*, relative specific ventilation sV* (measured with dynamic PET or estimated as change in expansion between two static HRCTs), average lobar expansion FThe fraction of the variance of sD* explained by sV* (0.38), by bifurcation effects (0.38), and by differences in deposition along feeding airways (0.31) were similar in magnitude. We could not directly estimate the contribution of aerosol that was exhaled. Differences in expansion did not explain any fraction of the variability in sD* among lobes. The dependence of sD* on sV* was high in subjects breathing with low fThe theoretical framework allowed us to analyze experimentally measured aerosol deposition imaging data. When considering bronchoconstricted asthmatic subjects, a dynamic measurement of ventilation is required to evaluate its effect on aerosol transport. The mechanisms behind the identified effects of f |
| Databáze: | OpenAIRE |
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