Siemens Acuson S2000, Instructions For Use Manual

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Appendi x A Technical Des cription
A - 34 Instructions for Use
2D-mode
Measurements Range or Formula Minimum Value Maximum Value
% Stenosis by Area 100(A1-A2)/A1 100(A1-Tol(A1)-A2-
Tol(A2))/(A1+Tol(A1))
100(A1+Tol(A1)-
A2+Tol(A2))/(A1-Tol(A1))
% Stenosis by Diam. 100(D1-D2)/D1 100(D1-Tol(D1)-D2-
Tol(D2))/(D1+Tol(D1))
100(D1+Tol(D1)-
D2+Tol(D2))/(D1-Tol(D1))
Amniotic Fluid Index* AFI=D1+D2+D3+D4 D1-Tol(D1)+D2-Tol(D2)+
D3-Tol(D3)+D4-Tol(D4)
D1+Tol(D1)+D2+Tol(D2)+
D3+Tol(D3)+D4+Tol(D4)
Bi-plane Volume (D1)(D2)(D3)(0.52) (D1-Tol(D1))(D2-Tol(D2))
(D3-Tol(D3))(.52)
(D1+Tol(D1))(D2+Tol(D2))
(D3+Tol(D3))(.52)
Strain Ratio M
ROI1
/M
ROI2
M
ROI
=Mean strain in a
region of interest
--- ---
* Values are adjusted for fewer than four distances (quadrants). For example, if the second and
fourth quadrants are measured, then the formula is "AFI=D2+D4." The minimum value is
"D2-Tol(D2)+D4-Tol(D4)" and the maximum value is "D2+Tol(D2)+D4+Tol(D4)."
Doppler Measurements
Doppler
Measurements Range or Formula Minimum Value Maximum Value
Velocity 20 – 600 cm/sec V-Tol(V) V+Tol(V)
Frequency
2F
0
Vcos θ /1540
F
0
=Carrier Frequency
2F
0
cos θ (V-Tol(V))/1540 2F
0
cos θ (V+Tol(V))/1540
Delta Velocity V1 - V2 V1-Tol(V1)-V2-Tol(V2) V1+Tol(V1)-V2+Tol(V2)
Delta Frequency
2F
0
cos θ (V1-V2)/1540 2F
0
cos θ (V1-Tol(V1)-
V2-Tol(V2))/1540
2F
0
cos θ (V1+Tol(V1)-
V2+Tol(V2))/1540
Time @ Slow Sweep 0 – 11.2 sec T-Tol(T)@ Slow Sweep T+Tol(T)@ Slow Sweep
Time @ Med Sweep 0 – 5.6 sec T-Tol(T)@ Med Sweep T+Tol(T)@ Med Sweep
Time @ Fast Sweep 0 – 2.8 sec T-Tol(T)@ Fast Sweep T+Tol(T)@ Fast Sweep
Time Averaged
Maximum Velocity;
TAMx
(MxVel
1
+MxVel
2
+…+
MxVel
N
)/N
N=Number of Velocities
Averaged
(MxVel
1
-Tol(MxVel
1
)+MxVel
2
-
Tol(MxVel
2
)+…+MxVel
n
-
Tol(MxVel
n
))/N
(MxVel
1
+Tol(MxVel
1
)+
MxVel
2
+Tol(MxVel
2
)+ …+
MxVel
n
+Tol(MxVel
n
))/N
Time Averaged Mean
Velocity; TAMn
(MnVel
1
+MnVel
2
+
…+MnVel
N
)/N
N=Number of Velocities
Averaged
(MnVel
1
-Tol(MnVel
1
)
+MnVel
2
-Tol(MnVel
2
)+
…+MnVel
n
-Tol(MnVel
n
))/N
(MnVel
1
+Tol(MnVel
1
)+
MnVel
2
+Tol(MnVel
2
)+ …+
MnVel
n
+Tol(MnVel
n
))/N
Time Averaged
Minimum Velocity;
TAMin
(MinVel
1
+MinVel
2
+…
+MinVel
N
)/N
N=Number of Velocities
Averaged
(MinVel
1
-Tol(MinVel
1
)+
MinVel
2
-Tol(MinVel
2
)+ …+
MinVel
n
-Tol(MinVel
n
))/N
(MinVel
1
+Tol(MinVel
1
)+
MinVel
2
+Tol(MinVel
2
)+ …+
MinVel
n
+ Tol(MinVel
n
))/N