A chest X-ray is one of the most commonly performed medical tests. It uses a very small dose of radiation to create an image of the lungs, heart, major blood vessels and the bones of the chest. It is quick, painless and widely available.
Common reasons a doctor may advise a chest X-ray
- A cough lasting more than two to three weeks
- Fever with cough or breathlessness, when pneumonia is suspected
- Coughing up blood
- Unexplained breathlessness or chest pain
- Suspected tuberculosis or follow-up during TB treatment
- After a chest injury
- Before certain surgeries or as part of some health assessments
What a chest X-ray can — and cannot — show
A chest X-ray can show pneumonia, fluid around the lung (pleural effusion), a collapsed lung (pneumothorax), an enlarged heart, and some masses or nodules.
However, a normal chest X-ray does not rule out every lung problem. Early interstitial lung disease, small nodules and airway diseases such as asthma may not be visible. Your pulmonologist may recommend a CT scan or breathing tests when needed.
Is the radiation harmful?
The radiation dose of a single chest X-ray is very low — roughly comparable to a few days of natural background radiation. Pregnant women should always inform staff before any X-ray.
This article is for general education and is not a substitute for personal medical advice. Please consult a doctor about your specific situation.
