GE Venue 50, Основное руководство пользователя

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User Maintenance
6-8
Venue 50
–
Basic User Manual
Direction 5446729-100 English Rev. 7
Clinical Measurement Accuracy
Basic Measurements
The following information is intended to provide guidance to the
operator in determining the amount of variation or measurement
error that should be considered when performing clinical
measurements with this equipment. Measurement error can be
contributed by equipment limitations and improper user
technique. Be sure to follow all measurement instructions and
develop uniform measurement techniques among all operators
to minimize the potential operator error. Also, in order to detect
possible equipment malfunctions that could affect measurement
accuracy, a quality assurance (QA) plan should be established
for the equipment that includes routine accuracy checks with
tissue mimicking phantoms.
Please be advised that all distance related measurements
through tissue are dependent upon the propagation velocity of
sound within the tissue. The propagation velocity usually varies
with the type of tissue, but an average velocity for soft tissue is
assumed. This equipment is designed for, and the accuracy
statements listed on are based on, an assumed average velocity
of 1540 m/s. The percent accuracy when stated applies to the
measurement obtained (not the full scale range). Where the
accuracy is stated as a percent with a fixed value, the expected
inaccuracy is the greater of the two.