Evaluation of the Effect of Lung Morphometry on the Deposition of Inhaled Particles

Sárkány Z¹, Kudela G², Horváth A³, Balásházy I⁴, Hofmann W⁵, Sabău M⁶

1 University of Medicine and Pharmacy, Târgu Mureș, Romania
2 Faculty of Informatics, Eötvös Loránd University, Budapest, Hungary
3 Chiesi Hungary, Budapest, Hungary
4 Environmental Physics Laboratory, Centre for Energy Research, Hungarian Academy of Sciences, Budapest, Hungary
5 Division of Physics and Biophysics, Department of Materials Research, University of Salzburg, Salzburg, Austria
6 Department of Physiology, University of Medicine and Pharmacy, Târgu Mureș, Romania

Introduction: The human respiratory tract is a complex, asymmetrical, tree-like system of tubular structures, optimized for the transport and distribution of respiratory gases. The objective of this study is to use a computerized lung model to study the effect of lung morphometry on the airway deposition of inhaled particles.
Material and methods: We used a stochastic lung model to simulate the total and regional deposition of 0.01–10 µm particles through oral breathing in sitting condition. The effect of lung morphometry was examined using the same model with a modified algorithm to create a fully symmetrical lung geometry.
Results: Total deposition curves show similar deposition trends for the two models, the symmetric model returning slightly lower deposition values for all particle sizes. In the bronchial region deposited fractions are highly similar, the symmetric model predicting deposition values that are 2.1–4.6% higher for particles in the 0.01–0.1 µm size range. In the acinar region deposition values are up to 27.6% lower in the case of 0.2 µm particles.
Conclusions: Our study suggests that the deposition of inhaled particles is dependent mainly on particle size, and to a smaller extent on the lung geometry the models are built on. Deposition fractions yielded by the two models are highly similar, although there is a shift in the deposition of inhaled particles from the acinar region towards the bronchial region in the symmetric model.