Plain Radiograph/X-ray

Authors: Mr Ben O’Sullivan*
                            Prof Stacy Goergen *

What is a plain radiograph/ X-ray?

This is the most simple, cost-effective and readily accessible imaging technique available. It provides excellent imaging details of bones, joints and areas of the body where there is substantial soft tissue differences in X-ray absorption; for example, in the thorax where there is marked X-ray differences between bone, lungs and soft tissues.

What are the generally accepted indications for a plain radiograph/ X-ray?

The most common indications for X-rays are:

• for the exclusion of fractures following trauma;
• assessment of joint or spinal disease;
• assessment of cardiopulmonary disease.

What are the prerequisites for having a plain radiograph/X-ray done?

A signed request from a referring clinician with appropriate and relevant clinical details.

What are the absolute contraindications for a plain radiograph/X-ray?

None. A plain X-ray is a low-dose examination that is cheap and readily available. The small risk must be weighed up against the benefit (see Adverse effects below).

What are the relative contraindications for a plain radiograph/X-ray?

Pregnancy or weight of patient (X-ray tables have weight limits).

What are the adverse effects of plain radiography/X-rays?

No short-term effects. Generally speaking, the benefit of the X-ray procedure is far more important than the small estimated risk (see InsideRadiology: Radiation risk of medical imaging for adults and children). At the dose levels that are utilised in diagnostic radiography, there is little or no evidence of health effects (ARPANSA 2008).

According to ARPANSA (2008) “There is good epidemiological evidence – especially from studies of the survivors of the atomic bombings – that, for several types of cancer, the risk increases roughly linearly with dose”. At low-dose levels (like that in diagnostic radiography), the risk is cancer or heritable mutations, and no such risk has yet been demonstrated in Japanese bomb survivors who received radiation doses comparable to those delivered by plain X-rays or radiographs. There have been no large-scale longitudinal studies of people exposed to diagnostic X-rays that would allow an accurate assessment of risk to be made.

For most plain radiographs/X-rays, the radiation dose is no more than the ionising radiation from the normal environmental background over a period of 1 year. The dose is considerably higher for some CT scans, angiography and some fluoroscopy procedures. However, the minimal risk of exposure to any type of medical ionising radiation needs to be weighed against the potential gain from the diagnostic information provided by the X-ray.

(For further information see InsideRadiology: Radiation risk of medical imaging for adults and children).

Is there any specific post-procedural care required following a plain radiograph/X-ray?

None.

Are there alternative imaging tests, interventions or surgical procedures to a plain radiograph/X-ray?

Ultrasound and MRI do not utilise radiation, and therefore might be considered as alternatives if diagnostically appropriate. Radiologists have expert knowledge of which imaging test is best suited to answer a clinical question. If you are unsure which is the most appropriate test, then please contact your local radiologist. For example, an ultrasound might be a better test than an X-ray to locate a non-metallic foreign body in the foot.

Further information about a plain radiograph/X-ray:

A radiologist should be consulted for more information.

Useful websites about plain radiograph/X-ray:

1. Radiation and health fact sheets (ARPANSA)
   www.arpansa.gov.au/RadiationProtection/Factsheets/index.cfm
2. International Commission on Radiological Protection
   www.icrp.org/
3. Australian Society of Medical Imaging and Radiation Therapy
   www.air.asn.au

References:

1. ARPANSA, Radiation protection. 2008, viewed 25 September 2008,
   www.arpansa.gov.au/RadiationProtection/Factsheets/index.cfm

*The author has no conflict of interest with this topic.

Page last modified on 31/8/2017.