ATS 535-H, Руководство пользователя

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Record these settings on the quality assurance record. These settings should be used for subsequent
testing.
Note: In addition to the above, this test should also be performed with output levels set at the highest and
lowest settings. This enables any changes in output to be more easily detected.
4. Position the transducer over the two 10 mm anechoic targets. This surface provides measurements at
depths of 3 and 13 cm.
5. Freeze image and obtain a hard copy.
6. Repeat steps 1-5 for the remaining scan surfaces, to provide measurements at remaining scanning
depths.
7. Examine the image to determine the last or deepest target structure displayed. Using the electronic
calipers or the timing markers measure the depth of this target.
8. Document the depth measurement on the quality assurance record.
Results
The depth of penetration should not shift by more than 1.0 cm, when using this phantom at same
instrument settings and transducer. If a discrepancy occurs corrective action should be considered by the
individual Ultrasound Department.
FUNCTIONAL RESOLUTION, DEFINITION AND FILL-IN
Description and Reason For Testing
Functional resolution is an imaging system's ability to detect and display the size, shape, and depth of an
anechoic structure within the test phantom. In practice, the data obtained will give a direct indication of
the minimum size structure the system is capable of resolving at a given depth.
Definition and Fill-in describes the imaging system's ability to detect and display the shape and echogenic
characteristics of a structure. Clinically, a correct diagnosis is dependent upon the system's ability to
differentiate between a cystic or solid structure versus echo patterns originating from the surrounding
normal tissue.
Testing Procedure
The Model 535-H is provided with two sets of anechoic target structures, at two depths from scan surface
#1. The ability to use all four scanning surfaces allows measurements to be obtained at 6 depths.
1. Place the phantom on a clean, flat surface with scanning surface #1 positioned for use.
2. Apply an adequate amount of low viscosity gel or water to the scan surface. If water is used,
fill the scanning well slowly to avoid introduction of air bubbles.
3. Adjust the instrument settings (TGC, output, etc.) to establish baseline values for "normal"
liver scanning. If the bottom of the phantom is seen, adjust the gain settings until image goes
entirely black. Record these settings on the quality assurance record. These settings should
be used for subsequent testing.
4. Position the transducer over the anechoic circular target group on the phantom, until a clear
image is obtained.
5. Freeze image and obtain a hard copy.
6. Repeat steps 1-5 with the remaining 3 scan surfaces.
7. Examine the images obtained to determine the smallest target visualized at the shortest and
longest depths. Due to the configuration of the sound beam small targets in the near field may
not be imaged.