Logo image
Airway Tree Segmentation in Serial Block-Face Cryomicrotome Images of Rat Lungs
Journal article   Open access

Airway Tree Segmentation in Serial Block-Face Cryomicrotome Images of Rat Lungs

Christian Bauer, Melissa A Krueger, Wayne J Lamm, Brian J Smith, Robb W Glenny and Reinhard R Beichel
IEEE transactions on biomedical engineering, Vol.61(1), pp.119-130
01/2014
DOI: 10.1109/TBME.2013.2277936
PMCID: PMC3925465
PMID: 23955692
url
http://doi.org/10.1109/TBME.2013.2277936View
Open Access

Abstract

A highly automated method for the segmentation of airways in the serial block-face cryomicrotome images of rat lungs is presented. First, a point inside of the trachea is manually specified. Then, a set of candidate airway centerline points is automatically identified. By utilizing a novel path extraction method, a centerline path between the root of the airway tree and each point in the set of candidate centerline points is obtained. Local disturbances are robustly handled by a novel path extraction approach, which avoids the shortcut problem of standard minimum cost path algorithms. The union of all centerline paths is utilized to generate an initial airway tree structure, and a pruning algorithm is applied to automatically remove erroneous subtrees or branches. Finally, a surface segmentation method is used to obtain the airway lumen. The method was validated on five image volumes of Sprague-Dawley rats. Based on an expert-generated independent standard, an assessment of airway identification and lumen segmentation performance was conducted. The average of airway detection sensitivity was 87.4% with a 95% confidence interval (CI) of (84.9, 88.6)%. A plot of sensitivity as a function of airway radius is provided. The combined estimate of airway detection specificity was 100% with a 95% CI of (99.4, 100)%. The average number and diameter of terminal airway branches was 1179 and 159 μm, respectively. Segmentation results include airways up to 31 generations. The regression intercept and slope of airway radius measurements derived from final segmentations were estimated to be 7.22 μm and 1.005, respectively. The developed approach enables the quantitative studies of physiology and lung diseases in rats, requiring detailed geometric airway models.
Image segmentation Airway segmentation serial block-face imaging cryomicrotome Lungs rat lung Biomedical measurement Rats Biomedical imaging

Details

Metrics

Logo image