Interpretation of Posterior Wall of Bronchus Intermedius and Subcarinal Region in Lateral Chest Radiographs

Sung, Dong Wook; Oh, Joo Hyeong; Yoon, Yup

Abstract

A lateral chest radiograph is frequently useful and sometimes decisive in detecting chest pathology. Certainparts, such as the posterior wall of the bronchus intermedius (PWBI) and subcarinal regions, can be evaluated onlyon lateral chest radiograph. The authors present and emphasize the findings of PWBI and subcarinal abnormalities. Abnormal PWBI, more than 3 mm thick, is seen in cases of minor degree of oblique position, pulmonary edema, inflammation, neoplasm and enlarged lymph nodes. It can also be seen in patients with subcarinal mass. The findings of subcarinal mass on lateral view are ill-defined increased opacity, fullness of the inferior hilarregion, doughnut sign, extra-density and thickening of the PWBI. Detection of changes in the PWBI and subcarinalregion may be the only diagnostic evidence of hilar and subcarinal disease and helps in its early detection priorto computed tomography.