X-rays and radiation: how much there really is

X-ray imaging does use ionising radiation. The question that counts is not whether there is radiation, but how much there is and what the image gives us. We are all constantly exposed to natural radiation from the ground, food, air and space, and this is the most useful yardstick for comparison.

An X-ray of an arm, leg or chest with a digital machine means a dose in the order of a few days of natural background radiation. An X-ray of the lumbar spine or abdomen is considerably higher, because the field is wider and the tissue denser, and is measured in months of natural background. Computed tomography, or CT, is higher still. The differences between tests are therefore large, and it makes no sense to lump them together.

This does not mean imaging carries no weight. A simple rule applies: every image must have a clear reason. Whether a test is justified is decided by the doctor, who weighs the expected benefit against the radiation dose. That is exactly why we do not carry out X-rays routinely or just in case, and why it is useful to bring previous images: sometimes the one you already have turns out to be enough for an answer.

The opposite mistake is more common than it seems. Refused or postponed imaging means that a fracture, inflammation or change in the lungs goes unrecognised, and when there is a sound indication these risks are greater than the risk of radiation. Children are more sensitive to radiation than adults, so the judgement is stricter for them, but even there the answer is not automatically no.

Pregnancy is a situation in which the answer is often no. If you are pregnant or think you might be, you must say so before the X-ray, even if you are not sure. The doctor weighs whether the test is urgent, whether it can be postponed, and whether there is a test without radiation, such as ultrasound or MRI, that answers the same question. Breastfeeding is not an obstacle to an ordinary X-ray.

The X-ray itself is quick. No special preparation is needed; before the image, remove jewellery, your watch, belt and other metal objects in the area being imaged, because metal creates a shadow on the image. The radiographer positions you for the ordered projection and asks you to keep still, and for a chest X-ray also to hold your breath. The image itself is taken in an instant and you do not feel it.

At Medicinski center Ljubljana we image the skeleton and chest with a digital X-ray. Imaging is self-pay, you do not need a referral, and booking is managed by the provider that runs the clinic. If a specialist is sending you, bring their report stating exactly the area and projection, otherwise the X-ray may have to be repeated. The images are reviewed and reported by a radiologist; when and how you receive the report is agreed when you book.