Tree-in-Bud Pattern of Pulmonary Tuberculosis on Thin-Section CT: Pathological Implications.
10.3348/kjr.2018.19.5.859
- Author:
Jung Gi IM
1
;
Harumi ITOH
Author Information
1. Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul 03080, Korea. imjgsnu@gmail.com
- Publication Type:Review
- Keywords:
Tree-in-bud;
Pulmonary tuberculosis;
Cluster of micronodules;
Radiology-Pathology correlation;
Centrilobular nodules
- MeSH:
Bronchioles;
Lung;
Trees;
Tuberculosis;
Tuberculosis, Pulmonary*
- From:Korean Journal of Radiology
2018;19(5):859-865
- CountryRepublic of Korea
- Language:English
-
Abstract:
The “tree-in-bud-pattern” of images on thin-section lung CT is defined by centrilobular branching structures that resemble a budding tree. We investigated the pathological basis of the tree-in-bud lesion by reviewing the pathological specimens of bronchograms of normal lungs and contract radiographs of the post-mortem lungs manifesting active pulmonary tuberculosis. The tree portion corresponds to the intralobular inflammatory bronchiole, while the bud portion represents filling of inflammatory substances within alveolar ducts, which are larger than the corresponding bronchioles. Inflammatory bronchiole per se represents the “tree” (stem) and inflammatory alveolar ducts constitute the “buds” or clubbing. “Clusters of micronodules”, seen on 7-mm thick post-mortem radiographs with tuberculosis proved to be clusters of tree-in-bud lesions within the three-dimensional space of secondary pulmonary lobule based on radiological/pathological correlation. None of the post-mortem lung specimens showed findings of lung parenchymal lymphatics involvement.
