I'm not sure, but should the doctor do an x-ray when diagnosing asthma?

Not usually: Chest x-ray is not routinely used in diagnosing asthma unless the doctor suspects something else may be happening. We have mostly replaced chest x-ray with low-energy ct of the chest since it provides far more details in the lungs than the chest x-ray does.

Doesn't find it: X-rays look at structure while asthma is about the function within the small airways.There are some x-ray changes (from normal) that occur during an attack, but that would be evident on exam.They might be taken to look for an infectious trigger and can show evidence of chronic lung disease, but the findings are not specific to asthma.The diagnosis is usually made from history,exam & lung function.