Interpreting CXRs

Question 1

Where can the costophrenic recess be found?

Answer 1

At the margin between the diaphragm and the ribs.

Question 2

What does a lobar collapse look like?

Answer 2

Displacement of the horizontal fissure is indicative of lobar collapse

Question 3

What happens if there is volume loss in the right upper lobe (as a result of collapse, for instance)

Answer 3

Horizontal fissure is displaced upwards

Question 4

What happens if there is volume loss of the right lower lobe (collapse)

Answer 4

The horizontal fissure is displaced downwards

Question 5

What is consolidation?

Answer 5

If alveoli and small airways fill with dense material, the lung is said to be consolidated
This may be due to infection (pneumonia, pus), fluid (pulmonary oedema), blood (haemorrhage) or cells (cancer)

Question 6

What does a consolidated lung look like?

Answer 6

If an area of the lung is consolidated it becomes dense and white
If larger airways are spared, they are of relatively low density (blacker

Question 7

What is an air bronchogram?

Answer 7

When large airways are spared of consolidation, they become less dense
Characteristic sign of consolidation

Question 8

What is a pleural effusion?

Answer 8

• A collection of fluid in the pleural space • Fluid gathers in lower part of chest, according to patient’s position

Question 9

What will a pleural effusion obscure if patient sits upright?

Answer 9

• Costophrenic angle/Hemidiaphragm

Question 10

What is a pneumothorax?

Answer 10

May form when there is air trapped in the pleural space This may occur spontaneously, or as a result of underlying lung disease

Question 11

What is the most common cause of pneumothorax?

Answer 11

Trauma, with laceration of the visceral pleura by fractured rib

Question 12

What is a tension pneumothorax?

Answer 12

If there is tracheal or mediastinal shift away from the pneumothorax, the pneumothorax is said to be under tension

Question 13

What can displace the trachea?

Answer 13

Anything that increases pressure or volume in the hemithorax will push the hemithorax and diaphragm away from that side.
Any disease that causes volume loss in one hemithorax will pull the trachea over towards that side

Question 14

What does this show? Picture 5

Answer 14

Asbestos plaque

Question 15

What is an asbestos plaque?

Answer 15

• Calcified asbestos related pleural plaques have a characteristic appearance and are generally considered to be benign

Question 16

What causes lung hyperexpansion?

Answer 16

• COPD

Question 17

What does lung hyperexpansion look like?

Answer 17

• Blunting of both costophrenic angles and flattened hemidiaphragms

Question 18

What is pneumoperitoneum?

Answer 18

• Lungs are normal, but air is seen under the diaphragm. Sign of bowel perforation,

Question 19

What is a simple pneumothorax?

Answer 19

• Pleural defect causes air to enter the potential pleural space and break the pressur potential, compromising lung inflation

Question 20

How is a simple pneumothorax different from a tension?

Answer 20

• Tension involves the formation of one way valve at point of injury, perimitting air to enter but not to escape.

Question 21

What is the cardiac index?

Answer 21

• The widest part of the heart and ribcage are measured laterally. • If heart is over 50% of the width of the thorax, it is enlarged

Question 22

What is the ABC system of systematic x ray analysis?

Answer 22

Airway Breathing Circulation Everything else

Question 23

What does a tension pneumothorax look like?

Answer 23

Mediastinum pushed to one side