GE SENOGRAPHE 800T, Руководство оператора

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PREP
ARING
AN EXAMINA
TION
GE Medical Systems SENOGRAPHE 800T
REV 6 om 2135575–100
2–2
The choice of priority to dose reduction or to optimum contrast is left to the discretion of the
operator.
Use of the AOP Mode provides the best quality/dose compromise for each priority selected by
the operator.
THIS MACHINE USES A SOPHISTICATED ALGORITHM TO
AUTOMATICALLY DETERMINE OPTIMAL PARAMETERS TO
PRODUCE MAMMOGRAMS (AOP). FOR THIS, MANY KVP/FILTRATION
COMBINATIONS ARE AVAILABLE TO BE CHOSEN FROM. IN REGULAR
AUTOMATIC EXPOSURE CONTROL (AEC) MODE, THE SAME
CONDITIONS ARE AVAILABLE, AND MAY BE CHOSEN BY THE USER.
HOWEVER, FOR BEST RESULTS, ONLY CERTAIN CONFIGURATIONS
SHOULD BE USED.
Compression
It is advised that sufficient breast compression be used to benefit the following image
quality/dose reduction advantages:
Compression reduces motion blurring.
Compression reduces geometric unsharpness by ensuring direct contact between breast
and image receptor, and by spreading apart glandular breast tissue.
Compression improves film contrast and reduces scattered radiation in proportion to the
reduction in the thickness of the tissue irradiated.
Compression spreads the breast laterally, and reduces the breast to a constant thickness.
This shortens exposure time, and consequently reduces the average glandular dose.
Good compression is obtained when the breast surface is taut to the touch.
Decompression can be programmed to occur automatically after exposure is complete
When exposure is complete, automatic decompression is available by pressing the button on
the right hand side of the control console.
Note: As a safety measure, the compression system is fitted with magnetic braking to avoid the
paddle falling in the event of a power cut. If such a power cut occurred during an
examination, a force of around 5 daN could remain on the compression paddle. To
disengage the patient, the paddle should be gently raised to counteract this compression
force.
SECTION 2
EXPOSURE MODE
2–1 AOP Mode
The AOP (Automatic Optimization Parameters) Mode controls radiation and allows the
system to select the main parameters.
It optimizes the filter/kV configuration as a function of the required image quality, and of the
composition of the breast being examined.
The AOP Mode includes the AEC Mode, and ensures constant density.
WARNING