Imaging of the chest

Question 1

Different ways to scan chest

Answer 1

Chest x-ray
CT
MRI
Nuclear medicine

Question 2

How to perform chest x-ray

Answer 2

Arms above head to move bone artefacts from lungs, put chest on plate and x-ray source comes through back

Question 3

PA x-ray

Answer 3

Rays come through back to plate at front of chest

Question 4

What is AP x-ray?

Answer 4

put x-ray source infront of patient - e.g. if doing x-ray in bed

Question 5

When will heart appear larger

Answer 5

Heart is more anterior in chest - larger in AP projection than PA

Question 6

Why can’t you see the right ventricle?

Answer 6

It is more central

Question 7

Why do you put your arms above your head for x-ray?

Answer 7

Scapulae wing forward out of way of lungs

Question 8

What do posterior ribs look like?

Answer 8

More horizontal towards spinal column

Question 9

What do anterior ribs look like?

Answer 9

Swing forward

Question 10

What is lateral x-ray better for?

Answer 10

Rib fractures/collapse
Pedicles of thoracic spine
Sternal fractures

Question 11

Why are coronal x-rays good?

Answer 11

Rib fractures easier to see
SOB and chest injury = CT needed
More rib fractures = higher care pathway

Question 12

When is sagittal x-ray good?

Answer 12

Spinal pathologies

Question 13

Why is LV larger in heart failure?

Answer 13

It is working harder

Question 14

What will pulmonary hypertension look like on x-ray?

Answer 14

Larger pulmonary trunk and knuckle

Question 15

What does left hilum do?

Answer 15

Crossing point of pulmonary veins and arteries

Question 16

Lobes and fissures in right lung

Answer 16

3 lobes - upper, lower and middle

Oblique and horizontal fissures

Question 17

Lobes and fissures in left lung

Answer 17

Two lobes - upper and lower

One fissure - oblique

Question 18

What is the major fissure?

Answer 18

Oblique

Question 19

What is the minor fissure?

Answer 19

Horizontal

Question 20

Right lung

Answer 20

• Oblique from T4/5 to anterior diaphragm
• Anterior half of lung is upper lobe, posterior is lower lobe
• Upper lobe divided by horizontal fissure
• Frontal x-ray: lower lobe extends high up - report may refer to zones and not lobes

Question 21

Trachea

Answer 21

• Cricoid cartilage (C6) to carina (T4-6)
• 16-20 incomplete C or U shaped cartilage rings
• Down, back and to right
• Mean diameter 15.2 mm in F and 18.2 mm in M

Question 22

Carina n

Answer 22

• Division into RMB and LMB
• Carinal angle 65 degrees (25 right and 40 left)
• RMB (2.5cm) LMB (5cm)
• Where trachea splits into bronchi

Question 23

What is a bronchogram

Answer 23

Patient inhales radio-opaque solution

Coats airway so you can see structures clearly

Question 24

Right main bronchus

Answer 24

• Right upper lobes - 3 segments (apical, posterior and anterior)
• Bronchus intermedius: right middle lobe (2 segments - med and lat) and right lower lobe (5 segments - apical, ant, post, lat, med)

Question 25

Left main bronchus

Answer 25

• Left upper lobe - superior division (2 segments - ant and apico-post) and inferior division (2 segments - sup and inf)
• Left lower lobe - 4 segments (apical, anteromedial, posterior, lateral)

Question 26

Insertions of diaphragm

Answer 26

Right crus L1-3

Left crus L1-2

Question 27

Openings into diaphragm

Answer 27

Aortic (T12) - thoracic duct, azygous and hemiazygous veins
Oesophagus (T10)- vagus nerve, oesophageal arteries
Caval (T8) - right phrenic nerve

Question 28

Where should NG tube be inserted?

Answer 28

Below T11 - preferably T12

Question 29

What is a well inspired film?

Answer 29

Diaphragm below 6th rib

Question 30

What is a poorly inspired film?

Answer 30

Diaphragm above 6th rib and has domed appearance

Question 31

Pulmonary arteries

Answer 31

• Right ventricle - main pulmonary artery - right and left pulmonary arteries - loop over corresponding veins and bronchi
• Pulmonary angiogram means needle in femoral vein
• Radiographic dye shows arterial tree - arterial venous malformations
• CT pulmonary angiogram and injecting radiographic fluid into vein shows pulmonary embolism - wait for contrast bolus to pass into pulmonary arteries
• Contrast shown as white and see any filling defects - PE shows black hole

Question 32

V/Q scans

Answer 32

• Nuclear medicine study
• Reserved for patients that you want to have lower radiation dose because less accurate
• Ventilation scanning: krypton gas inhaled (133-Xe)
• Perfusion scanning means injected into bloodstream
• Gamma camera used
• Perfusion can’t go into lung blocked by PE but ventilation can
• Consolidation - homogenous perfusion but no ventilation uptake - blocking air way not vessel

Question 33

Approach to x-rays

Answer 33

• Demographics - right x-ray for right patient
• Orientation - make sure it is up the right way
• Equipment - lines, NG tube, central lines, line tips
• Mediastinum - heart and vessels
• Lungs - trachea, size, vascularity, fissures, nodules, lines, pleura
• Review areas - behind heart/diaphragm, bones, soft tissue, under diaphragm
• Systematic approach reduces chance of missing something important

Question 34

What will surgical emphysema look like?

Answer 34

Hyperexpanded lungs

Question 35

What will pneumothorax look like on x-ray?

Answer 35

Lung has much greater volume

Question 36

What will tension pneumothorax look like on x-ray?

Answer 36

Mediastinum will shift to opposite side

Question 37

What will foreign body inhalation look like on x-ray?

Answer 37

Can’t see mediastinum or lung

Pressure difference causes lung expansion of opposite lung

Question 38

What is gas below the hemidiaphragm a sign of?

Answer 38

Abdominal perforation

Question 39

What is dextrocardia?

Answer 39

Heart flipped sides