1. To improve understanding of radiographic anatomy by correlating chest films and MDCT images. 2. To discuss common and less frequently occurring structures forming interfaces and lines on the frontal and lateral films. 3. To review the frequency with which these structures are seen. 4. To demonstrate how interfaces help characterize pathology.

1. Introduction 2. Review of airway anatomy on frontal and lateral radiographs with corresponding CTs 2.1 The hilar interfaces, including pulmonary vasculature and airways 2.2 Mediastinal interfaces, spaces and other structures 3. Frequency of radiographic landmarks and interfaces 4. Characterizing pathology using interfaces 4.1 Silhouette sign 4.2 Hilum overlay sign 4.3 Thoracoabdominal and cervicothoracic signs

Knowledge of the structures, interfaces and signs on the frontal and lateral chest radiographs facilitates the interpretation of normal anatomy and the development of a differential diagnosis for radiographic abnormalities. Correlation of chest radiographic findings and MDCT reconstructions in multiple planes provides a powerful presentational tool for improving resident and medical student education in thoracic anatomy.