Computerized (Axial) Tomography (CT)
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Computerized scanners are used for the examination
of body tissues. Most well known are EMI scans, Delta-Scans,
and Acta-Scanner. Unlike a conventional x-ray that sends a
broad beam of radiation over a large area, the CT scanner's
x-ray tube directs a thin, concentrated beam of radiation
through a cross section of the body detectors. The technique
involves recording of "slices" of the body with an x-ray scanner;
theses records are then integrated by computer to give a cross-sectional
image. A complete study of a patient usually takes 8 to 15
separate scans of 13 mm-thick slices of the body.
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From the readings, the computer constructs an image which is displayed
on a television screen where it can be photographed for a permanent
record. The precision of the scanner permits a more accurate diagnosis
of the extent of disease than any other external means. It can discover
tumors at an early stage and pinpoint their exact location. It may
avert the risk of exploratory surgery to determine if an organ is
diseased. CT scans can be performed with or without the use of contrast
media.
Emission Computerized Tomography (ECT)
SPECT: Single Photon ECT
Selected planes can be analyzed without interfering overlap from
other planes. For example: in liver scanning for metastasis, smaller,
deeper lesions can be better identified than with conventional
scans.
PET: Position Emission Tomography
Some elements, for example, oxygen, carbon and nitrogen, do not
have a single photon-emitting isotope suitable for conventional
imaging. PET permits investigation of cerebral glucose metabolism
and cerebral blood and, thus, measures chemical compounds of the
body.
Here is a report (Example
E11) of a CT (sometimes called CAT) scan of the chest. Abstract
what you think is pertinent in the report and then compare with
the suggested abstraction.

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