POSTER SECTIONS Coverpage Learning objectives Background Findings and procedure details Conclusion Personal information and conflict of interest References

ECR 2020 / C-04462

Classical findings on chest X-ray: what every first year radiology resident wants to know but is afraid to ask.

Congress:

ECR 2020

Poster Number:

C-04462

Type:

Educational Exhibit

Keywords:

Performed at one institution, Not applicable, Neoplasia, Infection, Education and training, Education, Contrast agent-intravenous, CT, Conventional radiography, Thorax, Respiratory system, Lung, Chest

Authors:

M. B. R. PINTO, T. Moriwaki, M. Sato, I. Lorensini, A. D. A. E. Castro; Sao Paulo/BR

DOI:

10.26044/ecr2020/C-04462

DOI-Link:

https://dx.doi.org/10.26044/ecr2020/C-04462

Fig. 1: Start the evaluation of a chest X-ray by the upper abdomen (highlighted in...

Fig. 2: Chest X-ray shows hyperinflation of the superior segment of the left lower lobe...

Fig. 3: Collapse of the right upper lobe caused by a central mass (yellow arrow) that...

Fig. 4: Chest X-ray shows increased opacity of the vertebral bodies (yellow arrow) only...

Fig. 5: Right tension pneumothorax with complete collapse of the right lung (yellow...

Fig. 6: Chest X-ray and CT show hydropneumothorax with a collapsed right lung (yellow...

Fig. 7: The deep sulcus sign is an indirect sign of a pneumothorax. Supine chest X-ray...

Fig. 8: Chest X-rays and CT show subcutaneous emphysema (yellow arrow) in the left...

Fig. 9: Chest X-rays show herniation of intra-abdominal content into the left...

Fig. 10: Chest X-ray shows ringlike opacities throughout the lungs (yellow arrow),...

Fig. 11: Azygos lobe is an anatomical variation of the apical segment of the right upper...

Fig. 12: The air crescent sign can be visualized in a pulmonary cavity, which results in...

Fig. 13: Chest X-rays show a retrocardiac opacity with gas/fluid level (yellow arrow).

Fig. 14: Chest X-ray and CT show accumulation of fluid within the pleural space.

Fig. 15: Chest X-ray shows bilateral free subdiaphagmatic gas (yellow arrow). There is...

Fig. 16: Chest X-ray and CT show right upper lobar collapse conditioning justaphrenic...

Fig. 17: Chest X-ray and CT show alveolar opacities with predominantly bilateral...

Fig. 18: Chest X-rays show grossly distended food-filled esophagus (yellow arrow).

Fig. 19: Chest X-ray shows branching, tubular lucencies of bronchi in an opacified lung...

Fig. 20: Hampton´s hump sign (red arrow), the wedge-shaped opacity of the peripheral...

Findings and procedure details

We propose a systematic evaluation of chest X-ray and present a case series of our practice with an objective to approach its main RX and CT imaging findings.

SYSTEMATIC EVALUATION OF CHEST X-RAY

The analysis of chest X-ray begins with the least interest areas and then progresses to areas of greatest interest.

The radiologist can start the evaluation by the upper abdomen, then examine the rib cage (soft tissues and bones), the mediastinal structures and finally the lung.

Abdomen

The structures that usually contain air are the stomach and the liver and splenic flexions of the colon.

The liver is always visible and the spleen is sometimes visible.

Chest

Begin by analyzing the right base, examine the soft parts of the chest wall (muscles and breasts), than ribs and shoulder in this sequence.

Finish by the left side, reversing the order of observation of the structures.

Mediastinum

Begin by making a general observation, looking for changes in contours, then proceed with a directed examination.

Lungs

Start at the right costophrenic angle, examine the right lung, then the left lung and left costophrenic angle.

The second step involves a comparison of the lungs side by side.

Tips

Although useful, profile radiography is often ignored. Begin by examining below the diaphragm; continue along the spinal column and examine soft tissues and bones posteriorly and anteriorly. Go back to the trachea and mediastinum.

Always examine previous radiographs whenever available. They can detect new diseases and evaluate changes in pre-existing disorders.

Fig. 1

CLASSICAL FINDINGS

Luftsichel sign

The word Luftsichel means "air crescent" in german.

Chest X-ray shows a radiolucent image with crescent morphology adjacent to the aortic button. It corresponds to the hyperinflation of the superior segment of the left lower lobe.

The finding is seen in the collapse of the left upper lobe.

Fig. 2

Golden S-sign

It is a deformation of the small fissure resulting from the existence of a neoplastic hilar mass.

When the right upper lobe bronchus is obstructed by an endobronchial lesion, there is elevation and medial displacement of the minor fissure with proximal convexity of the fissure due to the mass. This creates the ‘‘reverse S’’ characteristic of central obstructing bronchogenic carcinomas.

Fig. 3

More Black Sign and Spine Sign

More black sign is a normal radiographic finding (the gradual increased radiolucency of the vertebral bodies, from upper to lower chest).

When something abnormal (consolidation, lung mass, mediastinal mass and pleural fluid) interposes itself and superimposes on the lower thoracic spine, the lower vertebral bodies become more radiodense; this is known as the spine sign.

Fig. 4

Pneumothorax/Hidropneumothorax

Pneumothorax is the presence of air in the pleural space.

Typically, there is a visible visceral pleural edge (a very thin white line) and there are not lung markings at the periphery (peripheral space is radiolucent).

Hidropneumothorax is the presence of air and fluid in the pleural space.

Fig. 5 Fig. 6

Deep sulcus sign

It is an indirect sign of a pneumothorax.

It is seen on supine chest X-rays and it is characterized by a deep, lucent costophrenic angle.

Fig. 7

Pneumomediastinum

It is the presence of air in the mediastinum.

Chest X-ray shows lucent streaks, bubbles of air outlining mediastinal structures and visible mediastinal pleura.

Fig. 8

Diaphragmatic hernia

It is a defect in the diaphragm.

Chest X-ray shows: lack of normal hemidiaphragm contour; intrathoracic herniation of stomach, colon, small bowel; contralateral mediastinal shift; visualization of a nasogastric tube above the hemidiaphragm on the left side.

Fig. 9

Bronchiectasis

It is an irreversible dilatation of the airways, usually associated with recurrent infection, aspiration and obstructing bronchial lesions.

Chest X-rays shows parallel and ringlike opacities related to the thickened walls of dilated bronchi and tubular densities related to mucus-filled dilated airways.

Fig. 10

Azygos lobe

It is a rare anatomical variant, most frequently encountered in the right lung.

The radiographic appearance is a dense comma-shaped shadow which begins at the apex of the right lung and curves downwards and inwards to the mediastinum, ending below the level of the first costal cartilage.

Fig. 11

Air crescent sign

It appears as a peripheral crescentic collection of air surrounding a necrotic central focus of infection on chest X-rays and CT.

Fig. 12

Hiatus hernia

It is the herniation of abdominal contents through the esophageal hiatus into the thoracic cavity.

Chest X-ray shows retrocardiac opacity with gas/fluid level.

Fig. 13

Pleural effusion

Abnormal accumulation of fluid within the pleural space.

PA projection can show blunting of the costophrenic and cardiophrenic angles and fluid within the horizontal or oblique fissures. In large volume effusions, mediastinal shift away from the effusion may occur.

Fig. 14

Rigler and Cupola signs

These signs are seen in the presence of pneumoperitoneum.

The Cupola sign refers to nondependent gas that accumulate underneath the central tendon of the diaphragm in the midline.

The Rigler sign refers to the internal and external air that highlights the bowel wall.

Fig. 15

Juxtaphrenic peak sign

Triangular opacity projecting superiorly over the medial half of the diaphragm as a result of atelectasis of the upper lobe.

It is most commonly related to the presence of an inferior accessory fissure.

Fig. 16

Butterfly pulmonary opacities (in Paracoccidioidomycosis)

Paracoccidioidomycosis is a subacute or chronic systemic fungal infection endemic in South America.

Butterfly pulmonary opacities refer to a pattern of bilateral perihilar distribution of consolidation.

Fig. 17

Megaesophagus

It is a diffuse esophageal dilatation caused by a variety of conditions, such as Achalasia, Chagas disease, Scleroderma and distal obstruction.

Chest X-rays can show the absence of the gastric air bubble, air-fluid level, mediastinal widening and displacement of the azygoesophageal line.

Fig. 18

Air bronchogram sign

Air bronchogram occurs when the bronchi, which are not normally seen, become visible as a result of opacification of the surrounding lung parenchyma.

This sign reflects a pathologic airspace/alveolar process, in which the air that fills the alveoli is replaced by substances such as transudate, pus, blood or cells.

Fig. 19

Hampton hump sign

Hampton hump is one of the radiological signs observed in pulmonary embolism and lung infarction.

It consists in a peripheral, juxtapleural, wedge-shaped opacification with a rounded convex apex directed towards the hilum, representing a pulmonary infarction distal to an embolus.

Fig. 20