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Early airway structural changes in cystic fibrosis pigs as a determinant of particle distribution and deposition.

ABSTRACT: The pathogenesis of cystic fibrosis (CF) airway disease is not well understood. A porcine CF model was recently generated, and these animals develop lung disease similar to humans with CF. At birth, before infection and inflammation, CF pigs have airways that are irregularly shaped and have a reduced caliber compared to non-CF pigs. We hypothesized that these airway structural abnormalities affect airflow patterns and particle distribution. To test this hypothesis we used computational fluid dynamics (CFD) on airway geometries obtained by computed tomography of newborn non-CF and CF pigs. For the same flow rate, newborn CF pig airways exhibited higher air velocity and resistance compared to non-CF. Moreover we found that, at the carina bifurcation, particles greater than 5-?m preferably distributed to the right CF lung despite almost equal airflow ventilation in non-CF and CF. CFD modeling also predicted that deposition efficiency was greater in CF compared to non-CF for 5- and 10-?m particles. These differences were most significant in the airways included in the geometry supplying the right caudal, right accessory, left caudal, and left cranial lobes. The irregular particle distribution and increased deposition in newborn CF pig airways suggest that early airway structural abnormalities might contribute to CF disease pathogenesis.

SUBMITTER: Awadalla M

PROVIDER: S-EPMC3954455 | biostudies-other | 2014 Apr

REPOSITORIES: biostudies-other

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Early airway structural changes in cystic fibrosis pigs as a determinant of particle distribution and deposition.

Awadalla Maged M Miyawaki Shinjiro S Abou Alaiwa Mahmoud H MH Adam Ryan J RJ Bouzek Drake C DC Michalski Andrew S AS Fuld Matthew K MK Reynolds Karen J KJ Hoffman Eric A EA Lin Ching-Long CL Stoltz David A DA

Annals of biomedical engineering 20131206 4

The pathogenesis of cystic fibrosis (CF) airway disease is not well understood. A porcine CF model was recently generated, and these animals develop lung disease similar to humans with CF. At birth, before infection and inflammation, CF pigs have airways that are irregularly shaped and have a reduced caliber compared to non-CF pigs. We hypothesized that these airway structural abnormalities affect airflow patterns and particle distribution. To test this hypothesis we used computational fluid dyn ...[more]

PMID: 24310865

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Dataset Information

Early airway structural changes in cystic fibrosis pigs as a determinant of particle distribution and deposition.

Publications

Early airway structural changes in cystic fibrosis pigs as a determinant of particle distribution and deposition.

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