Sources Of Measurement Errors - FujiFilm SonoSite M-Turbo User Manual

Table 2: M Mode Measurement and
Calculation Accuracy and Range
Distance < +/- Acquisition Phantom
2%
plus
1% of
full
a
scale
Time < +/- Acquisition Phantom
2%
plus
1% of
full
scale c
Heart Rate < +/- Acquisition Phantom
2%
plus
(Full
c
Scale *
Heart
Rate/1
00) %
a. Full scale for distance implies the maximum depth of the
image.
b. An RMI 413a model phantom with 0.7 dB/cm MHz
attenuation was used.
c. Full scale for time implies the total time displayed on the
scrolling graphic image.
d. SonoSite special test equipment was used.
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Sources of measurement errors

Table 3: PW Doppler Mode Measurement and
Calculation Accuracy and Range
Velocity
cursor
0-26 cm
b
Frequency
cursor
d 0.01-10
Time
sec
a. SonoSite special test equipment was used.
b. Full scale for frequency or velocity implies the total frequency
d 5-923
or velocity magnitude, displayed on the scrolling graphic
bpm
image.
c. Full scale for time implies the total time displayed on the
scrolling graphic image.
Sources of measurement
errors
In general, two types of errors can be introduced
into the measurement:
Acquisition Error Includes errors introduced by
the ultrasound system electronics relating to
signal acquisition, signal conversion, and signal
processing for display. Additionally,
computational and display errors are introduced
by the generation of the pixel scale factor,
application of that factor to the caliper positions
on the screen, and the measurement display.
Algorithmic Error The error introduced by
measurements, which are input to higher order
calculations. This error is associated with
< +/- 2% Acquisition Phantom
plus 1% of
full scale b
< +/- 2% Acquisition Phantom
plus 1% of
full scale b
< +/- 2% Acquisition Phantom
plus 1% of
c
full scale
0.01
cm/sec-
550 cm/s
ec
0.01kHz-
20.8 kHz
0.01-10
sec