Chest X-rays and Pulmonary Embolism

General Rules

1. Check patient name, position, technical quality.
2. Soft tissue including breast, chest wall, companion shadow.
3. Review soft tissues and skeletal structures of shoulder girdles and chest wall.
4. Review abdomen for bowel gas, organ size, abnormal calcifications, free air, etc.
5. Review soft tissues and spine of neck.
6. Review spine and rib cage: check alignment, disc space narrowing, lytic or blastic regions, etc.
7. Review mediastinum:
A. overall size and shape
B. trachea: position
C. margins: SVC, ascending aorta, right atrium, left subclavian artery, aortic arch, main pulmonary artery, left ventricle
D. lines and stripes: paratracheal, paraspinal, paraesophageal (azygoesophageal), paraaortic
E. retrosternal clear space
8. Review hila:
A. normal relationships
B. size
9. Review lungs and pleura:
A. compare lung sizes
B. evaluate pulmonary vascular pattern: compare upper to lower lobe, right to left, normal tapering to periphery
C. pulmonary parenchyma
D. pleural surfaces
a. fissures - major and minor - if seen
b. compare hemidiaphragms
c. follow pleura around rib cage


Pulmonary Embolism
• can be done in conjunction with a ventilation-perfusion (V/Q) scan  it is difficult to diagnose pulmonary embolism on the x-ray alone
• VQ scan basically shows the parts of the lungs which are not receiving the air they should be  shows lowered perfusion

What to look out for:
• Small/medium pulmonary embolism
o Is often normal
o Linear atelectasis (partial lung collapse due to blockage)
o Blunting of the costophrenic angle (due to small effusiuon)
o Raised hemidiaphragm – present in some patients
o Wedge-shaped pulmonary infarct, abrupt cut-off of pulmonary artery, translucency of underperfused distal lung zone  rarer
o Previous infarcts – opaque linear scars
• Massive pulmonary embolism
o Pulmonary oligaemia  decrease in the size and number of pulmonary vessels due to vessel blockage or destruction
o Dilation of the pulmonary artery at the hila

- Rushmi
P.s. I have pictures, but it takes to long to stick them all up so, um, if anyone brings a laptop, can i use it? Just let me know before Friday. Thanks!