Chest x-ray: exposure (summary)
This is a basic article for medical students and other non-radiologists
Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review where E refers to "everything else".
Exposure (everything else)
At the end of the review, you need to remember to check for things that don't fit into the A-D categories and to look at review areas:
- behind the heart
- below the diaphragm
- soft tissues abnormalities (e.g. absent breast shadow)
The problem with apices is that many people forget to look above the clavicles. When reviewing a film, they start at the clavicles and work down, forgetting that they need review the bit of lung above the clavicles. Don't miss a Pancoast tumor because you've failed to look above the clavicles!
Behind the heart
Altered density in the retrocardiac region can fool people into forgetting to review this area thoroughly. I means that it is very easy to miss left lower lobe collapse, basal consolidation or a mass in this region.
Below the diaphragm
It is worth remembering that the diaphragmatic contour is such that the most inferior portion of the lower lobe is actually below the line of the diaphragm on the AP or PA chest x-ray. So, keep a look out for masses below the diaphragm that are not immediately obvious on the film.
Soft tissue abnormalities
There may be gas in the soft tissues (surgical emphysema) which can be really easy to miss if you don't look for it specifically. And a missing breast shaddow in a patient with previous breast cancer is a really important finding to pick up - it might make you look more carefully for evidence of bone or lung metastases.