Radiology VT: The Normal Chest X-Ray

Question 1

How are the lung fissures formed? [1]

Answer 1

by invagination of the visceral pleura

Question 2

Which bronchopulmonary segment is present in the right lobe but not in the left lobe? [1]

Answer 2

medial basal segment is not present in left lower lobe

Question 3

Label the structures in the following CXR [10]

Answer 3

1. trachea
2. hilum
3. lungs
4. diaphragm
5. heart
6. aortic knuckle
7. ribs
8. scapulae
9. breasts
10. stomach

Question 4

Aspiration occurs more commonly in which main bronchus and why? [3]

Answer 4

• more common in right main bronchus
  
  • more vertical and shorter than the left

Question 5

What is the accessory fissure and what does it contain? [3]

Answer 5

1. azygous fissure
2. contains the azygous vein with pleura wrapped around it

Question 6

Define the following:

1. costophrenic recess? [2]
2. costophrenic angle? [1]

Answer 6

1. costophrenic recess:
   
   • formed by the hemidiaphragm and the chest wall
   • contains the rim of the lung base which lies over the diaphragm
2. costophrenic angle:
   
   • the angle formed by the lateral chest wall and the diaphragm

Question 7

Where does fat tend to accumulate on a CXR? [1]

Answer 7

at the cardiophrenic angles

Question 8

What is the aortic knuckle? [1]

Answer 8

represents the left lateral edge of the aorta as it arches backwards over the left main bronchus and then continues as the descending aorta

Question 9

What are hilar points and which one is higher (the left or the right)? [2]

Answer 9

1. Hilar points are angles formed by the descending upper lobe veins and the lower lobe pulmonary arteries
   
   • they’re not always clearly visible
2. The left hilar point is higher than the right

Question 10

Label the following diagram: [8]

Answer 10

1. clavicle
2. AC joint
3. acromion
4. scapula
5. glenoid fossa
6. humerus head
8. coracoid process

Question 11

On which projection (AP or PA), can you accurately assess the size of the heart? [1]

Answer 11

PA projection

Question 12

What is the Silhouette sign? [2]

Answer 12

1. Normal adjacent anatomical structures of differing densities form a crisp silhouette or contour.
2. Loss of a specific contour can help determine the position of the disease process.

Question 13

What changes should you look out for when asssessing a CXR? [4]

Answer 13

1. Behind the heart
   
   • left lower lobe collapse consolidation can appear here
2. Crisp diaphragm is normal
   
   • if you lose part of diaphragm, it may suggest lower lobe collapse (but this may be a normal finding in some individuals)
3. Bones
   
   • fractures
4. Soft tissue
   
   • obstruction causing blurring