GE LOGIQ 7, Basic User Manual

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Quality Assurance
LOGIQ 7 Online Help 18
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Direction 2392536-100 Rev. 1
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 18-11 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 the front panel TGC slide pots to their center (detent)
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. Remember, TGC
slide pots are centered and should remain fixed. This may
NOT provide optimal cystic clearing.
5. Document all results for future reference and comparison.
Contact a Service Engineer if a greatly distorted image is
obtained.