GE Venue 50, Основное руководство пользователя

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Quality Assurance
Venue 50
–
Basic User Manual
6-31
Direction 5446729-100 English Rev. 7
Functional resolution
Description
Functional resolution is an imaging system's ability to detect and
display the size, shape, and depth of an anechoic structure, as
opposed to a pin target. See Figure 6-1 for more information.
The very best possible image is somewhat less important than
reproducibility and stability over time. Routine tests at the same
settings should produce the same results.
Benefit
The data obtained will give a relative indication of the smallest
structure the system is capable of resolving at a given depth.
Procedure
To measure functional 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 a vertical row of anechoic cyst
targets to typical depths for the probe being used.
4. Evaluate the cysts at various depths for a good (round)
shape, well-defined borders and no fill in.
5. Document all results for future reference and comparison.
Contact a Service Engineer if a greatly distorted image is
obtained.