1 Scope
This document, which is a Technical Specification, specifies requirements and methods
for periodic testing of the quality of diagnostic medical ultrasound systems using
reflection-mode (pulse-echo) imaging. Image measurement and interpretation workstations
are included.
NOTE Usually, "periodic testing" is referred to as "quality control (QC)" or quality assurance (QA).
This document includes minimum sets of such tests intended for frequent users of medical
ultrasound systems, for quality assurance professionals in their organizations, or those hired from other quality-control and/or
service-provider organizations. The procedures are for a wide range of more common
diagnostic ultrasound systems, currently operating from 1 MHz to 40 MHz, although
available phantoms meet the specifications only from 1 MHz to 23 MHz.
The tests are defined in three levels, with the simplest and most cost-effective performed
most frequently:
Level 1 comprises five quick tests/observations to be performed daily to monthly by
those normally operating the systems.
Level 2 includes one necessary test for all systems in addition to those of Level
1, two Level 1 tests performed more rigorously, two tests that are for special situations
or equipment, and one that is just optional, included because it is highly developed.
Level 2 tests are performed annually by those with meaningful quality assurance training.
Level 3 extends the two special situations tests to all systems, adds one optional
test and includes a periodic review of the QA programme.
Frequent distance-measurement accuracy tests are recommended in this document only
for certain classes of position encoding that are not now known to be highly stable
and without bias. QA in all dimensions is recommended in this document as the first test for such systems.
The test methodology is applicable for transducers operating in the 1 MHz to 23 MHz
frequency range. The types of transducers used with these scanners include
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a) electronic phased arrays,
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b) linear arrays,
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c) convex arrays,
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d) mechanical transducers,
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e) two-dimensional arrays operated in a 2D imaging mode,
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f) transducers operating in 3D imaging mode for a limited number of sets of reconstructed 2D images, and
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g) three-dimensional scanning transducers based on a combination of the above types.
All tests on scanners considered here evaluate basic pulse-echo techniques and might
detect most failures in other modes. Dedicated Doppler systems, or other systems for
detection of blood motion, are excluded from this scope as specialized equipment is
required to test them. Such test equipment can be specific to the intended application
of the Doppler system.
This document includes definition of terms and specifies methods for measuring the
maximum relative depth of penetration of real-time ultrasound B-MODE scanners, though this penetration measure is listed
as less frequently applied.