GE LOGIQ A100, Техническая публикация

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Patient Safety
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LOGIQ
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100 User Manual
2211157–100 Rev 0
Related Hazards (cont’d)
Although there have been no confirmed adverse effects
produced by diagnostic levels of ultrasound, avoid
unnecessary exposure of ultrasound energy to the
human body. Wrong scan settings, probe positioning and
tissue type can result in injury. Use the minimum
necessary output to get the best diagnostic image or
measurement during an examination. Begin an exam
with a probe that provides optimum focal depth and
penetration.
Follow the principle of “as low as reasonably achievable”
(ALARA) when scanning patients. Once an optimal
image is achieved, the need for prolonging the exposure
cannot be justified.
The principle of ALARA, which stands for “As Low As
Reasonably Achievable”, is to keep the radiation
exposure at the minimum level necessary to obtain the
diagnostic information. This principle is widely practiced
in medical X–ray protection where exposure at any level
is potentially harmful. Historically, ALARA was initiated as
a cautious approach for dealing with uncertain hazards
but has since become the principle method for reducing
the risk of injury from hazards that do not have safe
minimum thresholds.
While no minimum thresholds for harmful bio-effects
have been established with the use of diagnostic
ultrasound, the principle of ALARA can be readily
implemented on equipment incorporating an output
display. As the operator adjusts the equipment to
optimize the image quality, the display interactively
updates to indicate the effect on output.
Acoustic
Output
Hazard