Modeling Lung Structure in Rodents

Abstract

<p>Pre-clinical imaging has provided pulmonary researchers with a number of valuable tools for studying both the lung and lung disease. A greater understanding of the structure/function relationships within the rodent lung would help to bridge the gap between functional images of the lung and its underlying anatomy.</p> <p>The objectives of this work were to visualize and measure the components of rodent lung anatomy. Contrast-enhanced microCT images were used to visualize the airways and major blood vessels from both the Sprague-Dawley rat and the BALB/c mouse. These observations and measurements were used in the development of a pulmonary lung model containing both the conducting airways and blood vessels. The model can be applied to unenhanced images of the rodent lung to facilitate the regionalization of functional imaging data (SPECT/PET). The model has been used to simulate bronchoconstriction and deposition patterns of inhaled particles. Extensive validation revealed that the model was unable to fully reproduce the rodent lung and that further refinement is necessary.</p> <p>The finer structure of the rodent lung, which could not be resolved using our microCT system, was measured using histological sections of the rodent lung. Software was developed and validated to automatically quantify the increases in airspace size that are associated with several respiratory conditions.</p> <p>Together, this work sheds light on the underlying anatomy of the rodent lung that is present in both anatomical and functional images. The knowledge will help researchers to understand some of the structural changes that are occurring with the development of lung disease.</p>