X-ray

Published by Bupa's Health Information Team, May 2011.

This factsheet is for people who are having an X-ray, or who would like information about it.

An X-ray is a test that uses radiation to produce an image of the inside of the body.

You will meet the radiographer carrying out your procedure to discuss your care. It may differ from what is described here as it will be designed to meet your individual needs.

About X-rays

An X-ray is a quick and painless procedure that can help to diagnose and monitor a number of different health conditions. X-ray procedures are carried out by radiographers (health professionals trained to perform imaging techniques).

X-rays are commonly used to look for fractures in your bones after a fall or injury. They can also be used to look at your organs. For example, an X-ray image of your chest can show whether you have an infection in your lungs.

X-rays are a form of radiation. Unlike light radiation (normal light), which is absorbed or reflected by your skin, X-ray radiation passes through your body. An X-ray machine works by projecting a beam of X-rays through the part of your body that your doctor needs to look at. An X-ray sensitive detector then captures the radiation that comes out on the other side of your body in the form of a black and white image. This is called a radiograph.

Structures inside your body that are dense, such as your bones, absorb X-rays and show up white on the radiograph. Less dense structures, like the air in your lungs, let X-rays pass through them almost completely and show up black on the radiograph. Because different parts of your body vary in how dense they are, and absorb X-rays by different amounts, they show up on the radiograph as shades of grey, from the most dense (black) to the least dense (white).

The images captured by an X-ray machine are usually stored digitally and displayed on a computer screen. Sometimes X-rays are processed on film instead, and can be viewed by shining light over the film from behind.

What are the alternatives?

Depending on which part of your body is being looked at, a different type of imaging procedure may be more appropriate. Alternative tests may include an ultrasound scan, MRI scan or CT scan. Your doctor will discuss with you which test is most suitable.

Preparing for an X-ray

X-rays are usually done as an out-patient procedure in the radiology or imaging department of a hospital.

Your radiographer will discuss with you what will happen before, during and after the procedure. This is your opportunity to understand what will happen, and you can help yourself by preparing questions to ask about the risks, benefits and any alternatives to the procedure.

What to expect at the hospital

The examination is routinely done as an out-patient procedure in the radiology or imaging department.

Your radiographer will explain the procedure and ensure that you're happy to go ahead with the X-ray test. Radiographers are specially trained in imaging techniques and do most of the work in taking X-ray images. The images will then be sent to a radiologist (a doctor who specialises in using imaging methods to diagnose medical conditions).

What happens during an X-ray

X-rays usually only take a few minutes.

Depending on the area of your body that needs to be exposed to the X-rays, you may be asked to remove your clothing, put on a hospital gown and take off your jewellery. There will be a private area where you can do this.

You will then go to the X-ray room and your radiographer will help you to get into the right position on the X-ray machine. Alternatively, you may be asked to lie down on an X-ray table or sit in a chair at the side of the table, depending on the part of your body being looked at. You will be asked to stay still and sometimes, particularly if you’re having a chest X-ray, to take a deep breath and hold it for a few seconds.

                                                      X-ray

Your radiographer will operate the X-ray machine from behind a screen, but will be able to see and hear you at all times. He or she may need to take more than one X-ray, and so you may have to get into a number of slightly different positions on the machine.

What to expect afterwards

You will usually be able to go home when you feel ready.

Usually, a report will be sent out by the radiologist to your doctor; your X-ray images may also be sent. This can take several days. Before you go home, ask your radiographer when you can expect to get your results. It may be possible to ask for a copy of your images on a disc. This is particularly useful if you will be seeing a doctor in a different hospital or, for instance, if you will be travelling abroad.

What are the risks?

As with every procedure there are some risks associated with having an X-ray. However, the benefits of having the procedure usually outweigh these risks. You will be exposed to some X-ray radiation, but the amount you receive isn't considered to be harmful.

Different X-rays expose you to different doses of radiation. For example, if you have a chest X-ray you will be exposed to a very small amount of radiation (about the same that you would naturally be exposed to over two to three days). Other tests such as a barium enema and barium swallow and meal involve having many X-ray images and therefore the radiation dose is higher. However, doctors are trained to keep your exposure to a minimum. Ask your radiographer to explain how these risks apply to you.

If you’re pregnant

Although the radiation from an X-ray is generally thought to be safe for adults, it may harm an unborn baby. Therefore, X-rays won’t usually be used on pregnant women unless there is an urgent medical reason. But if you’re pregnant and your doctor decides you need to have an X-ray, a lead shield will be used to cover your abdomen (tummy) to help protect your baby.

If you think you could be pregnant, tell your doctor before the day of your appointment. Your doctor will advise you whether or not to go ahead with the procedure.

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.