What is a characteristic radiographic sign of pulmonary infarction?

• A. Kerley B lines
• B. Pleural effusion
• C. Hampton's hump sign
• D. Enlarged heart

Answer: (C)

Hampton's hump sign is a characteristic radiographic finding associated with pulmonary infarction. It appears as a wedge-shaped opacity in the peripheral areas of the lung fields on imaging, indicating an area of lung tissue that has become necrotic due to a lack of blood supply. This sign is typically observed in cases of pulmonary embolism, which can lead to infarction of lung tissue.

In the case of pulmonary infarction, the presence of these wedge-shaped opacities is significant because it directly correlates with the underlying pathology: the obstruction of pulmonary circulation resulting in the death of lung tissue due to ischemia. Recognizing Hampton's hump on imaging allows for a more accurate diagnosis and understanding of the patient's condition and potential complications.

Other findings like Kerley B lines are typically associated with pulmonary edema rather than infarction, pleural effusion indicates fluid accumulation rather than localized lung damage, and an enlarged heart signifies heart disease rather than a direct indicator of lung pathology. Thus, Hampton's hump is unique in its association with pulmonary infarction.