Journal
EXPERIMENTAL LUNG RESEARCH
Volume 41, Issue 3, Pages 135-145Publisher
TAYLOR & FRANCIS INC
DOI: 10.3109/01902148.2014.984085
Keywords
animal models; CT imaging; fluorescent microspheres; lung; particle deposition; ventilation
Categories
Funding
- National Heart, Lung, and Blood Institute [R01HL073598]
- PNNL through internal Laboratory Directed Research and Development LDRD [DE-AC05-76RL01830]
- NATIONAL HEART, LUNG, AND BLOOD INSTITUTE [R01HL073598] Funding Source: NIH RePORTER
Ask authors/readers for more resources
Purpose: Computer models for inhalation toxicology and drug-aerosol delivery studies rely on ventilation pattern inputs for predictions of particle deposition and vapor uptake. However, changes in lung mechanics due to disease can impact airflow dynamics and model results. It has been demonstrated that non-invasive, in vivo, 4DCT imaging (3D imaging at multiple time points in the breathing cycle) can be used to map heterogeneities in ventilation patterns under healthy and disease conditions. The purpose of this study was to validate ventilation patterns measured from CT imaging by exposing the same rats to an aerosol of fluorescent microspheres (FMS) and examining particle deposition patterns using cryomicrotome imaging. Materials and Methods: Six male Sprague-Dawley rats were intratracheally instilled with elastase to a single lobe to induce a heterogeneous disease. After four weeks, rats were imaged over the breathing cycle by CT then immediately exposed to an aerosol of similar to 1 mu m FMS for similar to 5 minutes. After the exposure, the lungs were excised and prepared for cryomicrotome imaging, where a 3D image of FMS deposition was acquired using serial sectioning. Cryomicrotome images were spatially registered to match the live CT images to facilitate direct quantitative comparisons of FMS signal intensity with the CT-based ventilation maps. Results: Comparisons of fractional ventilation in contiguous, non-overlapping, 3D regions between CT-based ventilation maps and FMS images showed strong correlations in fractional ventilation (r = 0.888, p < 0.0001). Conclusion: We conclude that ventilation maps derived from CT imaging are predictive of the 1 mu m aerosol deposition used in ventilation-perfusion heterogeneity inhalation studies.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available