GE Venue 50, Основное руководство пользователя

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Venue 50
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Basic User Manual
Direction 5446729-100 English Rev. 7
Contrast resolution
Description
Contrast resolution is the ability of an imaging system to detect
and display the shape and echogenic characteristics of a
structure. See Figure 6-1 for more information.
Specific values measured are less important than stability over
time. Routine tests at the same settings should produce the
same results.
Benefit
A correct diagnosis is dependent upon an imaging system's
ability to differentiate between a cystic or solid structure versus
echo patterns from normal surrounding tissue.
Method
A phantom with echogenic targets of different sizes and depths
should be used.
Procedure
To measure contrast resolution:
1. Set TGC to center position.
2. Gain and acoustic output can be adjusted, as necessary,
since these values are displayed on the monitor.
3. Scan a test phantom with echogenic targets at the depths
available.
4. Evaluate the echogenic targets for contrast between each
other and between the surrounding phantom material.
5. Document all results for future reference and comparison.
Contact a Service Engineer if the echogenic characteristics or
shapes of the targets appear distorted.