GE LOGIQ 7, Basic User Manual

Page: 962 / 984

User Maintenance
18
-
34 LOGIQ 7 Online Help
Direction 2392536-100 Rev. 1
Axial resolution
Descprition Axial resolution is the minimum reflector separation between two
closely-spaced objects to produce discrete reflections along the
axis of the sound beam. It can also be monitored by checking
the vertical size of known pin targets. See Figure 18-11 for more
information.
Axial resolution is affected by the transmitting section of the
system and the probe.
Benefit In clinical imaging, poor axial resolution displays small
structures lying close together as a single dot. This may lead to
improper interpretation of the ultrasound image.
Procedure To measure Axial resolution:
1. Scan a test phantom with precisely-spaced vertical pin
targets.
2. Adjust all scan controls, as necessary, for the best image of
the pin targets to typical depths for the probe being used.
3. Press Freeze to stop image acquisition.
4. Perform a standard distance measurement of the pin
vertical thickness at different points in the image. Record all
images for archiving.
5. Scan the vertical pins in zoom or at different depth/scale
factors.
6. Press Freeze to stop image acquisition; repeat the vertical
thickness measurements of the pins and record the images
for archiving.
7. Document the measurements for reference and future
comparison.
Axial resolution should remain stable over time. Contact a
Service Engineer if any changes are observed.