There are no radiological studies specific of asthma or allergy. Radiological studies are performed in these conditions rather to rule out other diseases, or complications often found in asthma and allergy.
Symptoms caused by asthma or allergy can be also caused by other diseases. As part of the differential diagnosis the doctor might ask for plain X-ray studies or computed tomography (CT) scans of the chest, nose, sinuses or others.
There are many diseases and acute or chronic complications diagnosed through radiological studies, like lung malformations, tumours, atelectasis, pneumothorax, pneumomediastinum, vascular malformations, sinusitis, adenoid hypertrophy, turbinate hypertrophy, or gastroesophageal reflux.
In some patients no radiological studies will be performed, while in others a thorough evaluation will be needed, depending on the individual symptoms.
Radiological studies are not painful and take a few minutes. CT scans may take longer and some patients may feel a claustrophobic sensation when inside the CT scanner. The amount of radiation is to be kept to a minimum, but the effect of repeated X-ray exams is cumulative.
Usually no specific preparation is needed for plain X-ray studies. If you are scheduled for another type or radiological study, ask your doctor about instructions.