Learning Radiology xray montage

Pneumonia - Left Upper Lobe

General Considerations
  • It is always best to localize disease on conventional radiographs using two views taken at 90° to each other (orthogonal views) like a frontal and lateral chest radiograph

  • Sometimes, only a frontal radiograph may be available, as in critically ill or debilitated patients who require a portable bedside examination

  • Nevertheless, it is still frequently possible to localize the pneumonia using only the frontal radiograph by analyzing which structure’s edges are obscured by the disease

  • Airspace disease may contain air bronchograms
    • The visibility of air in the bronchus because of surrounding airspace disease is called an air bronchogram

    • An air bronchogram is a sign of airspace disease

    • Bronchi are normally not visible because their walls are very thin, they contain air and they are surrounded by air

    • When something like fluid or soft tissue replaces the air normally surrounding the bronchus, then the air inside of the bronchus becomes visible as a series of black, branching tubular structures—this is the air bronchogram

    • What can fill the airspaces besides air?

    • Fluid, such as occurs in pulmonary edema

    • Blood, e.g., pulmonary hemorrhage

    • Gastric juices, e.g., aspiration

    • Inflammatory exudate, e.g., pneumonia

    • Water, e.g., near-drowning 

    left upper lobe pneumonia, air bronchogram

    Left Upper Lobe Pneumonia
    . There is airspace disease in the left upper lobe with fluffy, indistinct margins (red arrow) containing air bronchograms (white arrows). This was found to be a staphylococcal pneumonia.