1. The Normal Chest X-Ray

2. The CXR on the next slide is normal. How would you interpret it?
Introduction
Most of the chest x-rays you will see will be normal
In order to recognise abnormality, you need to know what a normal CXR looks like
The CXR on the next slide is normal. How would you interpret it?

4. General Principles Have a systematic approach
Interpret the CXR in conjunction with the clinical findings
Always compare with previous CXR if available to assess for change
Ask yourself “does my interpretation make sense?”

5. Systematic Approach Name/marker/rotation/ penetration Lines/metal work
Heart
Mediastinum
Lungs
Zones (upper/middle/lower)
Bones
Diaphragm
Soft Tissues

6. Systematic Approach Name/marker/rotation/ penetration
clavicles equidistant from spinous processes of thoracic spine
can just see lower thoracic spine

7. Systematic Approach Lines/metal work Look for:
Sternal wires (implies previous thoracic surgery)
Tip of endotracheal tube (2cm above carina)

8. Systematic Approach Lines/metal work
Tip of central venous lines at origin of superior vena cava. See tubes and lines presentation.

9. Systematic Approach Heart
Occupies up to 50% of the maximum internal thoracic diameter on a standard PA erect view
Cannot comment on heart size on AP view because of magnification of heart

10. Systematic Approach Mediastinum
Hilar vascular structures should be crisply defined
No widening of mediastinum
Trachea should be central

11. Systematic Approach Lungs Compare upper, mid and lower zones
upper zone
Compare upper, mid and lower zones
Look between ribs for lung detail
Remember to look “behind” the heart
middle zone
lower zone

12. Systematic Approach Bones Look at each rib in turn Clavicles
Scapulae and humeri if visible
Lower cervical and thoracic spine

13. Systematic Approach Diaphragm
Both diaphragms should form a sharp margin with the lateral chest wall
Both diaphragm contours should be clearly visible medially to the spine
Position of stomach gas bubble (not present on this CXR)

14. Systematic Approach Soft Tissues
Supraclavicular fossae (enlarged nodes)
Lateral chest wall (surgical emphysema)
Under diaphragm (pneumoperitoneum)

15. How would you summarise this?

16. “This is an erect chest X-Ray of an adult male
“This is an erect chest X-Ray of an adult male. The heart is not enlarged, the mediastinal contours are normal and the lungs are clear”

17. Take Home Points Be systematic
Review with history and physical examination in mind