Signs in chest Xray Dr. Archana Koshy

RADIOLOGICAL ANATOMY

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

• 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

Air BronchogramA 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

AIR BRONCHOGRAM

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

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

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.

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.

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

WESTERMARK SIGN

• Decrease of vascularization at the periphery of the lungs due to mechanical obstruction or reflex vasoconstriction in pulmonary embolism .

FLEISCHNER SIGN

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.

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.

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.

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

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 ).

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 .

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.

Luftsichel Sign

This peri-aortic lucency has been termed the luftsichel sign, derived from the German words luft (air) and sichel (sickle).

DOUGHNUT SIGN

• Occurs when mediastinal lymphadenopathy occurs behind the bronchus intermedius in the subcarinal region

• Lymphadenopathy is seen as lobulated densities on lateral radiographs

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)