User Guide
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2. Baseline measurements:
The rst set of measurements taken will be the baseline measurements for the
combination of system settings and phantom. Record the system settings and
phantom serial number used to acquire each measurement along with
your measurement results. On subsequent scans, refer to the baseline results
to determine if the ultrasound system has drifted to an unacceptable level. It is
each facility's responsibility to establish the magnitude of drift allowed
before corrective action is warranted.
3. Allowable deviation from baseline measurements:
The difference between the original baseline measurements and subsequent
measurement should be calculated and recorded. At some point the difference
will be large enough that some action is required (call service, replace system,
etc.). Each facility needs to determine the action level for each test. You should
refer to the user’s manual of your ultrasound scanner and note the stated
accuracies of the system’s general imaging measurements. These stated ac-
curacies may greatly inuence the conclusion made when evaluating the ultra-
sound system. For example, if the measurement accuracy for your system
is 10% for distances up to 2 cm, the scanner may detect 2.0 cm as being any
where from 1.8 cm to 2.2 cm and still be functioning properly. The user is
responsible for establishing action levels.
4. Frequency of system assessment:
How often each system is evaluated is also up to each facility to determine.
CIRS recommends at least annually.
Reference the accreditation programs established by the ACR and AIUM at
www.acr.org or www.aium.org for further guidance on establishing a QA program.
TESTING PROCEDURES
The following sections outline procedures for routine quality control tests with the
Model 040GSE. It may be useful to refer to the target map, shown in the Specica-
tions section of page 14, when reviewing these procedures.
UNIFORMITY TESTING
Uniformity is dened as the ability of the machine to display echoes of the same
magnitude and depth with equal brightness on the display. This is a good test to
ensure all crystals within the transducer are functioning.
1. Apply coupling gel to the scanning surface or ll the water trough with tap water.
2. Position the transducer on the scanning surface in a region with a minimum
number of targets.