What is X-ray (radiography)?
Radiography involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
An X-Ray makes images of tissues in the body, including the hand, wrist, arm, foot, ankle, knee, leg or spine.
A X-ray is used to:
- Determine whether a bone has been fractured or if a joint is dislocated
- Ensure that a fracture has been properly aligned and stabilized for healing following treatment
- Determine whether there is a build-up of fluid in the joint or around a bone
- Guide orthopaedic surgery, such as spinal repair, joint replacement and fracture reductions
- Evaluate injury or damage from conditions such as infection, arthritis, abnormal bone growths or other bone
- Diseases, such as osteoporosis
- Assist in the detection and diagnosis of cancer
- Locate foreign objects
- Evaluate changes in bones
Most x-rays require no special preparation.
You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewellery, eye glasses and any metal objects or clothing that might interfere with the x-ray images.
Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant.
Many imaging tests are not performed during pregnancy because radiation can be harmful to the foetus. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby.
Any old films or should be brought along to your procedure as they may assist the Radiologist.
The equipment typically used for x-rays consists of an x-ray tube suspended over a table on which the patient lies. A drawer under the table holds the x-ray film or image recording plate.
A portable x-ray machine is a compact apparatus that can be taken to the patient in a hospital bed or the emergency room. The x-ray tube is connected to a flexible arm that is extended over the patient while an x-ray film holder or image recording plate is placed underneath.
X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special image recording plate.
Different parts of the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of grey and air appears black.
X-ray images are maintained as hard film copy (much like a photographic negative) or, more likely, as a digital image that is stored electronically. These stored images are easily accessible and are sometimes compared to current x-ray images for diagnosis and disease management.
The technologist, an individual specially trained to perform radiology examinations, positions the patient on the x-ray table and places the x-ray film holder or digital recording plate under the table in the area of the body being imaged.
When necessary, sandbags or pillows will be used to help the patient hold the proper position. A lead apron may be placed over the patient’s pelvic area to protect it from radiation.
The patient must hold very still and may be asked to keep from breathing for a few seconds while the x-ray picture is taken to reduce the possibility of a blurred image. The technologist will walk behind a wall or into the next room to activate the x-ray machine.
The patient may be repositioned for another view and the process is repeated. At least two images (from different angles) will be taken and often three images are needed if the problem is around a joint (knee, elbow or wrist).
An x-ray may also be taken of the unaffected limb, or of a child’s growth plate (where new bone is forming), for comparison purposes.
When the examination is complete, the patient will be asked to wait until the technologist determines that the images are of high enough quality for the radiologist to read.
A bone x-ray examination is usually completed within 5 to 10 minutes.
A bone x-ray examination itself is a painless procedure.
You may experience discomfort from the cool temperature in the examination room. You may also find holding still in a particular position and lying on the hard examination table uncomfortable, especially if you are injured. The technologist will assist you in finding the most comfortable position possible that still ensures x-ray image quality.
A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyse the images and send a signed report to your primary care or referring physician, who will share the results with you.