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Normal Xray

Xrays are a form of invisible light discovered in 1895 by Wilhelm Rontgen. Although you can't see normal xrays, they can be picked up on photographic film. A normal Xray works like shining a flashlight through the palm of your hand. If you look on the other side, you can clearly see the outlines of your bones from the soft tissues of your hand.

normal xray cartoon

Normal Xray

You might think of a normal Xray as a picture of bones, but that's only half the picture. A radiologist's trained eye can also appreciate air spaces like the lung (which looks black) and fluid (which looks white like bone). In the normal chest xray picture below you can see the black air filled areas on both sides of a normal lung. On the abnormal xray picture below, one lung is opacified.

Normal Chest Xray
Pneumonia Chest Xray (Left)
normal chest xray picture
abnormal chest xray

Doctors learn to read xrays by memorizing what a normal xray looks like and comparing this mental image to the xray in front of them. After seeing many xrays, reading an Xray becomes as second nature as reading a newspaper.

xray machine picture

Xray Exposure Dose

A single Xray exposure is equivalent to about 3 days of natural cosmic radiation exposure in the outdoors.

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    Last Updated:
    April 22 2016
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