Skip navigation

X-ray

X-rays are a type of electromagnetic radiation, just like visible light.

An x-ray machine sends individual x-ray particles through the body. The images are recorded on a computer or film.

  • Structures that are dense (such as bone) will block most of the x-ray particles, and will appear white.
  • Metal and contrast media (special dye used to highlight areas of the body) will also appear white.
  • Structures containing air will be black, and muscle, fat, and fluid will appear as shades of gray.

How the Test is Performed

The test is done in a hospital radiology department or in the health care provider's office. How you are positioned depends on the type of x-ray being done. Several different x-ray views may be needed.

You need to stay still when you are having an x-ray. Motion can cause blurry images. You may be asked to hold your breath or not move for a second or two when the image is being taken.

The following are common types of x-rays:

How to Prepare for the Test

Before the x-ray, tell your health care team if you are pregnant, may be pregnant, or if you have an IUD inserted.

Metal can cause unclear images. You will need to remove all jewelry and you may need to wear a hospital gown.

How the Test will Feel

X-rays are painless. Some body positions needed during an x-ray may be uncomfortable for a short time.

Risks

X-rays are monitored and regulated so you get the minimum amount of radiation exposure needed to produce the image.

For most x-rays, the risk of cancer or defects is very low. Most experts feel that the benefits of appropriate x-ray imaging greatly outweigh any risks.

Young children and babies in the womb are more sensitive to the risks of x-rays. Tell your health care provider if you think you might be pregnant. 

Alternative Names

Radiography

References

Geleijns J, Tack D. Medical physics: radiation risks. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 6th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2014:chap 1.

Mettler FA, Jr. Introduction: an approach to image interpretation. In: Mettler FA, ed. Essentials of Radiology. 3rd ed. Philadelphia, PA: Saunders Elsevier; 2013:chap 1.

Update Date: 9/8/2014

Updated by: C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

MedlinePlus Topics

Images

Read More

A.D.A.M Quality Logo

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2014, A.D.A.M., Inc. Duplication for commercial use must be authorized in writing by ADAM Health Solutions.

A.D.A.M Logo