Radiographic Signs

Question 1

Steeple Sign

Answer 1

The narrowing of the subglottic airway, upper throat, such that the airway looks like the steeple of a church.

Question 2

Air bronchogram sign

Answer 2

Radiographic appearance of an air-filled bronchus as it passes through an area of increased anatomic density, as in pulmonary edema and pneumonia.

Question 3

Silhouette Sign

Answer 3

Loss of the normal radiographic silhouette or contour.

Something normally visible is hidden because of an change in the density of the surrounding tissue.

Question 4

Double Density Sign

Answer 4

Sign of left atrial enlargement

Usually the right border of the left atrium is not visible on the CXR because it is contiguous with the right atrium and it lies right in the middle of the chest where it usually gets obscured by a number of other structures. However, as the left atrium increases in size it will stretch well across the midline and create a second shadow along the right heart border.

Question 5

Oreo Cookie Sign

Answer 5

Indicated pericardial effusion

Oreo cookie sign – seen on the lateral film. This is seen in front of the heart just above the diaphragm. This sign exists because fluid absorbs ever so slightly more x-rays than fat does.

Question 6

Deep sulcus sign

Answer 6

Evidence of a pneumothorax

Occasionally seen in AP films of patients in a semi-recumbent position. The costophrenic sulcus deepens.