4. Silhouette Sign
• The loss of the lung/soft tissue interface due to the
presence of fluid in the normally air-filled lung
• If an intrathoracic opacity is in anatomic contact
with a border, then the opacity will obscure that
border
• Commonly seen with the borders of the heart,
aorta, chest wall, and diaphragm
5.
6.
7. • Used to describe the location of a lesion at the inlet of the thoracic cavity.
• In this anatomical space, the posterior portions of the lung apices are located more
superiorly than the anterior portions .
• A lesion clearly visible above the clavicles on the frontal view must lie posteriorly and be
entirely within the thorax.
• If the cranial border of the lesion is obscured at or below the level of the clavicles, it is
located at the anterior mediastinum
CERVICOTHORACIC SIGN
8.
9. Air Bronchogram
A tubular outline of an airway made visible due to the filling of the surrounding
alveoli by fluid or inflammatory exudates
Conditions in which air bronchograms are seen:
• Lung consolidation
• Pulmonary edema
• Non-obstructive pulmonary atelectasis
• Interstitial disease
• Neoplasm
• Normal expiration
15. HILUM OVERLAY SIGN
• The hilum overlay sign refers to an appearance on frontal
chest radiographs of patients with a mass projected at the
level of the hilum which is in fact either anterior or posterior
to the hilum.
• When a mass arises from the hilum, the pulmonary vessels
are in contact with the mass and as such their silhouette is
obliterated.
• The sign was first described by Benjamin Felson
16.
17.
18. DEEP SULCUS SIGN
• The deep sulcus sign describes the radiolucency extending from the lateral
costophrenic angle to the hypochondrium
• It is an important clue indicating possible pneumothorax in chest x-rays obtained in
the supine position.
• When plain films are taken with the subject in an upright position, the free air in the
pleural space gathers at the apicolateral space.
• In the supine position, the air accumulating at the anterior space forms a triangular
radiolucency that makes the inferior borders of the lateral costophrenic angle
conspicuous
19.
20. Air crescent (“meniscus”) sign
• The air crescent (“meniscus”) sign is the result of air
accumulation between a mass or nodule and
normal lung parenchyma.
• It is most frequently encountered in neutropenic
patients with aspergillosis.
21.
22. SPINNAKER SIGN
The spinnaker sign (the angel wing sign) is a sign of pneumomediastinum seen on
neonatal chest radiographs.
It refers to the thymus being outlined by air with each lobe displaced laterally and
appearing like spinnaker sails.
23.
24.
25. HAMPTON HUMP SIGN
• It is a wedge-shaped, pleura-based consolidation with a
rounded convex apex directed towards the hilus.
• This sign was first described by Aubrey Otis Hampton.
• It is usually encountered at the lower lobes and heals with
scar formation
26.
27. WESTERMARK SIGN
• Decrease of vascularization at the periphery of the
lungs due to mechanical obstruction or reflex
vasoconstriction in pulmonary embolism .
30. Bulging Fissure Sign
The bulging fissure sign refers to lobar consolidation where the affected
portion of the lung is expanded.
It is now rarely seen due to the widespread use of antibiotics.
31.
32.
33.
34. Continuous Diaphragm Sign
Continuous lucency outlining the base
of the heart, representing
pneumomediastinum .
Air in the mediastinum tracks
extrapleurally, between the heart and
diaphragm .
Pneumopericardium can have a similar
appearance but will show air
circumferentially outlining the heart.
35. Fallen Lung Sign
• This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus .
• The bronchial fracture results in
the lung to fall away from the
hilum, either inferiorly and
laterally in an upright patient or
posteriorly, as seen on CT in a
supine patient.
• DD:
Pneumothorax causes a lung to
collapse inward toward the hilum.
36. FLAT WAIST SIGN
• This sign refers to flattening of the contours of the aortic knob and adjacent main
pulmonary artery .
• It is seen in severe collapse of the left lower lobe and is caused by leftward
displacement and rotation of the heart
37. Finger in Glove Sign
The finger in glove sign can be seen on either chest radiograph or CT chest and refers to the
characteristic sign of a bronchocele
In bronchial obstruction, the portion of the bronchus distal to the obstruction is dilated
with the presence of mucous secretions (mucus plugging ).
38.
39. GOLDEN “S” SIGN
• When a lobe collapses around a large central mass, the peripheral lung collapses
and the central portion of lung is prevented from collapsing by the presence of
the mass.
• The relevant fissure is concave toward the lung peripherally but convex centrally,
and the shape of the fissure resembles an S or a reverse S .
40. Juxtaphrenic Peak Sign
• This sign refers to a small triangular shadow that obscures the dome of the
diaphragm secondary to upper lobe atelectasis .
• The shadow is caused by traction on the lower end of the major fissure, the
inferior accessory fissure, or the inferior pulmonary ligament.
41. Luftsichel Sign
This peri-aortic lucency has been termed the luftsichel sign, derived from the
German words luft (air) and sichel (sickle).
42. DOUGHNUT SIGN
• Occurs when mediastinal lymphadenopathy occurs behind
the bronchus intermedius in the subcarinal region
• Lymphadenopathy is seen as lobulated densities on lateral
radiographs
43.
44. SCIMITAR SIGN
• Indicates anomalous venous return of the right inferior pulmonary vein (total or
segmental) directly to the hepatic vein, portal vein or inferior vena cava.
• A tubular-shaped opacity extending towards the diaphragm along the right side
of the heart is seen (Fig. 9).
• The abnormal pulmonary vein resembles a Turkish sword called a “pala”.
• The scimitar sign is associated with congenital hypogenetic lung syndrome
(scimitar syndrome)
