X-Ray, Ultrasound, MRI: Three Ways Doctors See Inside You
In 1895, a German scientist named Wilhelm Rontgen was experimenting with a glowing glass tube in his lab when he noticed something strange nearby was glowing too, even with objects in between. He had discovered a new kind of invisible ray, and he even used it to take the very first X-ray photo ever - a picture of his wife's hand, showing her bones and her wedding ring clearly through her skin.
What You'll Learn
- Three kinds of medical imaging: X-ray, ultrasound, and MRI - What each type of scan is best at showing doctors - Who discovered X-rays, and when - Why doctors pick a different scan depending on the job
X-Rays: Seeing Through Skin
X-rays are a type of invisible light that passes easily through soft parts of your body like skin and muscle, but gets blocked by hard, dense bone. That's why an X-ray picture shows bones as bright white shapes against a darker, see-through background. Doctors and dentists use X-rays to check for broken bones and cavities because bones and teeth show up so clearly.
Ultrasound: Listening with Sound Waves
An ultrasound machine sends out sound waves pitched far higher than human ears can hear. These waves bounce off organs and tissues inside the body, and the machine turns the echoes into a moving picture on a screen. Doctors have used ultrasound since the 1950s to check on babies growing inside their mothers, because unlike X-rays, ultrasound uses no radiation at all.
MRI: A Giant Magnet Camera
An MRI machine, developed for medical use in the late 1970s and 1980s, uses an extremely strong magnet along with radio waves to build a detailed picture of soft tissue, like the brain or a torn muscle. An MRI scan takes longer than an X-ray or ultrasound and the machine is loud, but it uses no radiation and shows soft tissue far more clearly than an X-ray can.
MRI magnets are so strong they can pull a metal wheelchair or oxygen tank clear across the room, which is why every patient and every object made of metal has to be checked and removed before a scan begins.
Match each imaging tool to what it is best at showing doctors.
Terms
Definitions
Drag terms onto their definitions, or click a term then click a definition to match.
Which type of medical imaging uses sound waves instead of radiation?
Who took the first X-ray photograph in 1895?
Design an Imaging Center Chart
Make a poster with three columns labeled X-ray, Ultrasound, and MRI. In each column, draw a simple symbol for that machine and write one sentence explaining what it is best at helping doctors find. Deliverable: a finished three-column poster comparing all three imaging types.
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