Subpulmonic Pleural Effusion

  • Etiology: non-infected fluid in pleural space, common causes are infection (Streptococcus pneumonia, Staphylococcus aureus, group A Streptococcus, Mycoplasma, Tuberculosis), cardiac failure
  • CXR: elevation of the hemidiaphragm with lateralization of the apex of the hemidiaphragm on the AP view, decubitus view will show free flowing pleural effusion
  • US: clear pleural fluid between the inferior border of the lung and the diaphragm
  • DDX: diaphragm eventration, diaphragm paralysis

Cases of Subpulmonic Pleural Effusion

CXR and CT of subpulmonic pleural effusion and empyema
CXR AP (above) shows a right lower lobe infiltrate and elevation of the right hemidiaphragm and lateralization of its apex. Coronal 2D reconstruction from CT with contrast of the chest (below) shows a loculated fluid collection between the inferior border of the right lung and the right hemidiaphragm.