1. Computerized Axial Tomography
(CAT)
SCANS
By Abby Jeffers
And
James Kloss

2. CAT scans menu
• Before CAT scans • What CT scanners
• Development of CAT look like
scans • How do they work
• Overview of CT scans • Benefits of CT scans
• What CT scans for in • Risks of CT scans
the body • Evolution of the CAT
scan
When you see this picture click on it to
come back to the menu.
Works Cited

3. Before CAT Scans
The problems with x-rays:
 X-ray radiographs offer only a two-
dimensional image
 In a radiograph, a 3-D mass becomes a
2-D image and it is hard to tell
individual tissues apart
 It is difficult to determine which bones
and tissues are overlying and which are
underlying
http://www.asnt.org/publications/mate
rialseval/basics/may00basics/may00bas
ics.htm

4. Development of CAT Scans
• Godfrey Hounsfield and Allan
Cormack are credited as the
inventors of the CAT scan
• Cormack developed the
theoretical principals behind
reconstructing 2-dimensional
images into one 3-D image
• Hounsfield was the designer
and builder of the first CAT
scan machines
• (http://www.aps.org/publicati
ons/apsnews/200411/history.c
fm)

5. Overview of CAT Scans
• CAT scans are noninvasive medical tests to help
doctors diagnose patients and treat their medical
conditions.
• Uses X-rays and a computer to create images
of the inside of the human body.
• These scans can help doctors diagnose major
medical problem and disease.

6. What do they scan for in the body
• CAT scans internal organs, bones, soft tissue,
and blood vessels.
• CAT scans provide better clarity than X-rays
and reveals more important details than X-
rays too.

7. How do they work
• In many ways CAT scans work very much like
any other X-ray examination devices.
• In conventional X-rays small burst of radiation
are aimed a the body and shot through the
body.
• The result if a image that is recorded on
photographic film or a special image
recording plate.

8. How do they work 2
• Now CAT scans are very similar to X-rays because
in a CAT scan there are numerous X-rays that
rotate around A
• At the same time the X-rays are shooting beams
of radiation that is being received by X-ray
detectors on the opposite side of the patient.
• At the same time the examination table that you
are laying on moves in and out of the machine.
• The movement of the table creates a spiral path
for the X-ray beam to follow.

9. How do they work 3
• The CAT scan shoot X-ray beams at every
angle for 360 ° around the body.
• A special computer process this large amount
of data and produces a 2-D cross section of
the human body.
• This technique is called Helical or Spiral CAT

10. Benefits of CAT scan
• It is painless, noninvasive, and very accurate.
• CAT scans can provide information on bone,
soft tissue, and blood vessels all at the same
time.
• Fast and simple
• Provides real time imaging
• No radiation remains in patients body after
CAT scan.

11. Risks of CAT scans
• Slight chance of cancer from excessive
exposure to radiation.
• Pregnant women should not use CAT scans
unless needed to because of the potential risk
to the baby.
• Children should not have too many CAT scans
because they are more sensitive to radiation.

12. What they look like
• CAT scans are typically a large box
like machine with a hole or a
short tunnel in the center.
• There is a examination table that
slides into and out of the tunnel.
• The computer workstation the
process information from the
scan is located in a separate
room.

13. Evolution of the CAT scan
• First-generation CAT • Today, fifth-generation
scanners had one x-ray scanners have detectors
source and one and x-ray tubes that are
detector, which rotated switched on one at a
around the patient time all around the
patient.

14. Works Cited
• http://www.asnt.org/publications/materialsev
al/basics/may00basics/may00basics.htm
• http://www.aps.org/publications/apsnews/20
0411/history.cfm
• http://www.radiologyinfo.org/en/info.cfm?pg
=bodyct#part_one
• http://www.mayfieldclinic.com/pe-ct.htm