GE LOGIQ 200 Quality Assurance Manual page 82

GE MEDICAL SYSTEMS
REV 1
4-2 Probe Q/A – System Performance Test
Complete the tests in the Probe/QA matrix on each of the available probes listed, as described below:
• The following tests are an overall indication of performance with a Tissue Equivalent Phantom.
• Record each parameter permanently in the most economical method for the customer.
(It is acceptable to record multiple parameters on a single shot, as long as they are clearly indicated)
• The Q/A Results should be kept on file with the checklist as required by any accrediting organization
1. Lateral Resolution—Acquire an Image that demonstrates the best LATERAL resolution for the probe
under test
TERMS: This defines how well the system/probe can display two targets side by side. Depending on your
phantom use the resolution group that has targets with decreasing distances between them. The smallest
visible distance of two on the same horizontal plane is the Lateral Resolution. See Figure 4-1.
ACQUISTION: Scan the phantom with the Resolution group centered in the image, position the probe
to place this group in the center of the focus at approximately 1/2 of the maximum penetration. Adjust
the TGC / Image Gain / Focus to optimize the image. Zoom in on this group if necessary to display the
smallest separation visible. Make a hard copy.
ALTERNATIVE: If a lateral resolution group is not available on your phantom, freeze the image and take
a measurement of one of the 1mm target wires nearest the focus of the transducer, at approximately
1/2 total penetration depth. Remember that the target is physically 1mm in diameter. If the minimum
measurement is 3mm, then the lateral resolution is 3mm.
2. Axial Resolution—Acquire an Image that demonstrates the best available AXIAL resolution for the
probe under test.
TERMS: This defines how well the system/probe can display two targets above and below each other.
Depending on your phantom use the resolution group that has targets with decreasing distances
between them. The smallest visible distance of two on the same vertical plane is the Axial Resolution.
See Figure 4-1.
ACQUISTION: Scan the phantom with the Resolution group centered in the image, position the probe
to place this group in the center of the focus at approximately 1/2 of the maximum penetration. Adjust
the TGC / Image Gain / Focus to optimize the image. Zoom in on this group if necessary to display the
smallest separation visible. Make a hard copy.
ULTRASOUND QUALITY ASSURANCE REFERENCE MANUAL
Illustration 4-1 Axial and Lateral Resolution
4-2
Make a hard copy of this measurement.
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