What to look for in the apparently normal radiograph

If the chest radiograph appears normal then the following should be checked for: (1,2)

• a mastectomy
• a small apical pneumothorax
• a fluid level below the heart, due to a hiatus hernia
• collapse of the right middle lobe and loss of clarity of the right heart border
• absence of the outline of the left diaphragm behind the heart (sail sign) as a result of left lower lobe collapse
• deviation of the trachea
• paratracheal lymphadenopathy
• air beneath the diaphragm
• dextrocardia with the film reversed
• always check the apices, hila, behind the heart and the costophrenic angles

Reference

1. Kelly B. The chest radiograph. Ulster Med J. 2012 Sep;81(3):143–148.
2. Hodler J et al. Diseases of the Chest, Breast, Heart and Vessels 2019-2022: Diagnostic and Interventional Imaging [Internet]. A Systematic Approach to Chest Radiographic Analysis. Published online: February 20, 2019.