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RADIOLOGY open house presentation

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Or,
Why do you want to x ray my cat?
How does this stuff work anyway? Is it magic?
Radio: Radio stations transmit music on radio waves. Radio waves are
also emitted by stars and gases in space.
Microwave: Microwaves cook your popcorn, but are also used by
astronomers to learn about the structure of nearby galaxies.
Infrared: Night vision goggles pick up infrared light from objects with
heat. In space, infrared light helps us map the dust between stars.
Visible: Our eyes detect visible light. Fireflies, light bulbs, and stars all
emit visible light.
Ultraviolet: Ultraviolet radiation is emitted by the Sun and is the reason
skin tans and burns.
X-ray: The veterinarian uses X-rays to image your pet, and airport
security uses them to see through your bag (and your clothes).
Gamma ray: Doctors use gamma-ray imaging to see inside your body.
The biggest gamma-ray generator of all is the Universe.
Wilhelm Conrad Röntgen (27 March 1845 – 10 February 1923)
was a German physicist, who, on 8 November 1895, produced
and detected electromagnetic radiation in a wavelength range
today known as X-rays or Röntgen rays, an achievement that
earned him the first Nobel Prize in Physics in 1901.
The first radiographic image ever was of Röntgen’s wife’s
left hand, clearly showing her wedding ring.
The heart of an X-ray generator is the X-ray tube. The X-ray tube
contains a cathode, which directs a stream of electrons into a
vacuum, and an anode, which collects the electrons and evacuates
the heat generated. When the electrons hit the target, about 1% of
the resulting energy is emitted as X-rays, the remaining 99%
released as heat.
1.
2.
3.
4.
5.
Air
Fat
Soft tissue
Bone
Metal
Analog is traditional film x rays. Much like photography, film is exposed
to light to make an image. In radiography, the film is held between two
screens in a cassette. The screens emit light when exposed to x rays and an
image of whatever is between the x ray generator (i.e. your cat) and the
cassette is captured. The film is developed with chemicals like traditional
black and white film.
With CR systems, the film, intensifying screen, and cassette used in
analog systems are replaced with an imaging plate. The plate has a
similar look and feel to a traditional film cassette.
With CR, the feel of acquiring an image is similar to analog. As with
film, the CR cassette is placed and an exposure is made.
The cassette is then loaded into an imaging reader. Inside the reader, the
plate is exposed to lasers that interpret the information on the plate and
translate it into a radiographic image. The imaging plate is then erased
by white light inside the imaging reader and is ready to use again.
Radiographic images can tell the veterinarian a lot about your cat’s
health. By comparing body structures to known normals, much can be
learned about what’s going on inside your cat.
п‚Ё
We live in a radiation filled environment. Cosmic rays
bombard us from outer space, radon is present in our
homes, and radionuclides in the stone constructing
our buildings and even the food we eat give off
radiation. On average, we can get 360mrem of
radiation a year just from living on earth.
The principle of ALARA is designed to help
radiology technicians and their patients to keep
their radiation exposure As Low As
Reasonably Achievable. This is achieved by
keeping exposure times as short as possible,
keeping as far away from the source as possible
and wearing lead protective equipment to
shield themselves.
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