Chest x-ray review (basic)
- this is a basic article for medical students and non-radiologists
Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Chest radiographs are frequently performed and a fantastic tool for making diagnoses of acute and chronic conditions, as well as acting as a tool for follow up.
There are many systematic ways to review a chest x-ray. The important thing is to get into the habit of having a systematic approach. If you do the same thing every time you look at a chest x-ray, you will be much less likely to make a mistake.
Start off the same way each time you look at a film. Every time you look at an x-ray or other scan, think about:
- who, what, why, where and when
When looking at chest x-rays, also think about:
- lines and tubes
Read in more depth: initial review
A, B, C, D, E
One of the easiest systems for reviewing a chest x-ray is A, B, C, D, E (using the same headings as ALS (advanced life support):
- A: airway
- B: breathing (lungs and pleural spaces)
- C: circulation (cardiomediastinum)
- D: disability (fractures and dislocations)
- E: exposure (everything else)
The airways are often overlooked
- start at the top and follow the trachea down in the midline to the carina
- trace the right and left main stem bronchi
- the angle between the left and right mainstem bronchi shouldn't be much more than 90 degrees
Read in more depth: airways
Breathing (lungs and pleural spaces)
- compare each size in all 4 zones looking for altered density or focal mass lesions
- check around the lungs starting laterally, from the apex down to the costophrenic angle
- does the lung extend to the chest wall
- is there a pneumothorax?
- check both costophrenic angles
- is there an effusion?
- ensure you can trace the hemidiaphragms to the spine
- check the cardiac borders up to the hilar structures
Read in more depth: breathing (lungs and pleural spaces)
Assessment of the mediastinum is predominantly about looking at the heart, but it is imperative to remember the other structures in the mediastinum.
Assess the size of the heart, review the aortic knuckle and the upper mediastinal contour. After that, check the pulmonary vessels and the hilar structures. The left hilum is usually higher than the right.
The final thing to look for is a hiatus hernia with a retrocardiac fluid-fluid level.
Read in more depth: circulation (cardiomediastinum)
Check the bony thorax, especially the ribs for any evidence of fracture. If the shoulders have been includes on the film, check the glenohumeral joints and the clavicles.
Read in more depth: disability (fractures)
Exposure (everything else)
At the end of the review, you need to remember to check for other things that don't fall into the A-D categories. This includes free gas within the abdomen (pneumoperitoneum), abnormalities in the soft tissues of the thorax including surgical emphysema and absent breast shadows.
Read in more depth: exposure (everything else)
Double-check the apices (masses, pneumothorax), hila (masses, lymphadenopathy), retrocardiac zone (lobar collapse, hiatus hernia) and below the diaphragm (tubes and free air).
Finally, always compare to old films.
Read in more depth: review areas