The Chest X-ray - Basics

Question 1

Describe an x-ray and a radiograph

Answer 1

An electromagnetic wave of high energy and very short wavelength which is able to pass through many materials opaque to light - X-Ray

Absorbed to different degrees by different tissues displaced as levels of contrast on a grey scale photograph/ digital image - radiograph

Question 2

What’s the CXR dose and what is that in comparison to the UK background dose?

Answer 2

0.02 msg

Very low

x3 days worth of background radiation

Question 3

What’s the normal orientation for X-rays to be taken, what are the problems if it’s taken the opposite way?

Answer 3

Standard: posterior to anterior

But if need to be sat down taken

Anterior to posterior -> heart looks magnified

Question 4

What do you need to be able to see in a radiograph to say it’s an adequate film for inclusion?

Answer 4

1st rib

Lateral margin of ribs

Costophrenic angle (diaphragm meets ribs)

Question 5

What’s the problem if the radiograph is rotated? How can you check this isn’t the case?

Answer 5

If rotated one side is magnified

Check by alignment of spinous process should be central to clavicle bones

Question 6

What phase do you take a CXR in? What should you be able to see if the person is healthy? What could be some reasons for not seeing this? What’s the problem with it being taken not in this phase?

Answer 6

Inspiratory phase

If normal should see 5th to 7th anterior ribs at MCL

Causes of exaggerated expansion:
Obstructive airways disease

Problems with incomplete inspiration: big heart, increased lung markings, may think consolations present but actually just non-expanded alveoli

Question 7

What could a flattened diaphragm show?

Answer 7

COPD/ emphysema

If asymmetric: tension pneumothorax

Question 8

What is penetration? What shows adequate penetration?

Answer 8

Degree to which x-rays pass through the body (if dose is high enough= adequate)

Vertebra just visible through heart
Complete left hemidiaphragm visible

Question 9

What is an artefact, what are some e apples and what problems could they cause?

Answer 9

External/ iatrogenic material which obstructs view e.g.

Clothes,
Surgical/ vascular lines,

Hair- long could be confused for surgical emphysema

Pacemaker- could block cancer behind

Question 10

Which of the main bronchi should be higher?

Answer 10

The left

If hilar points are altered suggests Lung pathology

Question 11

3 zones of the lung?

Answer 11

Upper
Middle
Lower

Question 12

Which of the lungs fissures can you see? What might you see as well in heart failure?

Answer 12

Can see horizontal not oblique fissures

Fluid may collect here I’m heart failure

Question 13

What is a costophrenic angle? What’s the sign called when fluid collects in the costophrenic recess?

Answer 13

Angle where the ribs meet the diaphragm

Pulmonary meniscus sign

Question 14

What would obscure the diaphragm?

Answer 14

Consolidation or a mass

Question 15

If the stomach bubble is present on the right rather than the left what should you check? What could it mean?

Answer 15

Check the markers to ensure right and left are right way round

Could be situs inversus

Question 16

What are the markings of the heart on left and right?

Answer 16

Right atrium and left ventricle

If atrial enlargement carene opens up

Question 17

What’s the main mediastinal contour? What’s it above and what could the disappearance of this mean?

Answer 17

The aortic knuckle

just above the aorto-pulmonary window (gap that disappears if problem with aorta or there is a LN/ mass present)

Question 18

What’s a mediastinal contour on the right hand side and what creates it?

Answer 18

Right para- tracheal stipe from the azygos vein

Question 19

What can you do if you are unsure if something is a nipple marking?

Answer 19

Put paper clips around the nipples and re-take the CXR

Question 20

What can cause the loss of the crisp line of the vertebral stripe?

Answer 20

TB spondylodiscitis