The Chest X-ray - Basics Flashcards
Describe an x-ray and a radiograph
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
What’s the CXR dose and what is that in comparison to the UK background dose?
0.02 msg
Very low
x3 days worth of background radiation
What’s the normal orientation for X-rays to be taken, what are the problems if it’s taken the opposite way?
Standard: posterior to anterior
But if need to be sat down taken
Anterior to posterior -> heart looks magnified
What do you need to be able to see in a radiograph to say it’s an adequate film for inclusion?
1st rib
Lateral margin of ribs
Costophrenic angle (diaphragm meets ribs)
What’s the problem if the radiograph is rotated? How can you check this isn’t the case?
If rotated one side is magnified
Check by alignment of spinous process should be central to clavicle bones
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?
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
What could a flattened diaphragm show?
COPD/ emphysema
If asymmetric: tension pneumothorax
What is penetration? What shows adequate penetration?
Degree to which x-rays pass through the body (if dose is high enough= adequate)
Vertebra just visible through heart
Complete left hemidiaphragm visible
What is an artefact, what are some e apples and what problems could they cause?
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
Which of the main bronchi should be higher?
The left
If hilar points are altered suggests Lung pathology
3 zones of the lung?
Upper
Middle
Lower
Which of the lungs fissures can you see? What might you see as well in heart failure?
Can see horizontal not oblique fissures
Fluid may collect here I’m heart failure
What is a costophrenic angle? What’s the sign called when fluid collects in the costophrenic recess?
Angle where the ribs meet the diaphragm
Pulmonary meniscus sign
What would obscure the diaphragm?
Consolidation or a mass
If the stomach bubble is present on the right rather than the left what should you check? What could it mean?
Check the markers to ensure right and left are right way round
Could be situs inversus
What are the markings of the heart on left and right?
Right atrium and left ventricle
If atrial enlargement carene opens up
What’s the main mediastinal contour? What’s it above and what could the disappearance of this mean?
The aortic knuckle
just above the aorto-pulmonary window (gap that disappears if problem with aorta or there is a LN/ mass present)
What’s a mediastinal contour on the right hand side and what creates it?
Right para- tracheal stipe from the azygos vein
What can you do if you are unsure if something is a nipple marking?
Put paper clips around the nipples and re-take the CXR
What can cause the loss of the crisp line of the vertebral stripe?
TB spondylodiscitis
