Case 32: Chest PA View

Young boy with fever

Right Lower Zone Consolidation with upper zone consolidates as well.

Silhouette Sign shows the consolidation to be in the right lower lobe

The heart (a soft tissue density structure - near white) lies adjacent to lung tissue (near air density - near black).

A crisp contour or 'silhouette' is formed at the interface of these two tissue densities.

Silhouette Sign : It refers to the loss of borders between two thoracic structures.

Loss of clarity of the right heart contour (formed by the right atrium) implies disease of the right middle lobe

Loss of distinction of the left heart contour indicates an abnormality of the lingula