Gammex Optimizer, Руководство пользователя

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13
Grey Scale Applications
Metastases are sometimes slightly hyperechoic or hypoechoic compared with the surround-
ing tissue. If the scanner is not measuring grey levels accurately, the metastases may not be
detected. The Quantitative Measurement ensures that the grey level signal is measured con-
sistently. The Qualitative Measurement ensures that grey levels are displayed on the monitor
consistently. By performing these tests, the user can determine the optimal system settings for
measuring grey levels, which can then be used in clinical applications.
Phantom Desiccation
Over time, the phantom’s water-based gel and blood-mimicking material will slowly lose moisture.
This process is accelerated by high temperatures, incorrect storage, and damage to the case or
scanning surface. Consistently storing the phantom in an air-tight container will contribute greatly
to long phantom life. Properly storing your phantom will reduce the amount of moisture lost per
year. For instructions on how to properly store and take care of your phantom, go to the Caring
for Your Phantom section.
For most climate-controlled environments, the phantom weight should be checked every six
months. Phantoms used in high temperature/low humidity environments or in mobile situations
should be tested more frequently. As the phantom desiccates, the scanning surface may flatten
out. It is suggested that the phantom be sent in for rejuvenation once it has lost 10-15 grams of
its original weight. If the phantom has lost more than 20 grams, Gammex cannot guarantee that
the phantom will be able to rejuvenate successfully.
Charts and Graphs
Refer to the Charts and Graphs section of the manual CD to find the appropriate charts and
graphs for your 1425A phantom, which include:
Phantom Weight Chart
Data Sheet
Doppler QC Test Data Sheet
B-Mode QC Test Data Sheet