Siemens ACUSON Antares Instructions For Use Manual page 220

6 T e c h n i c a l D e s c r i p t i o n
2D-Mode Measurements
2D-mode
Measurements Range or Formula
Distance 0-34 cm
Distance Ratio D1/D2
Mean Distance (D1+D2+D3)/3
Ellipse π{1/2[D1
Circumference
Ellipse Area π(D1)(D2)/4
Ellipse Volume
(π/6)(D1)(D2)
(D1 = axis of
rotation)
Trace 0 – 85cm
Circumference
Trace Area 0 – 450 cm
% Stenosis by Area 100(A1-A2)/A1
% Stenosis 100(D1-D2)/D1
by Diam.
Amniotic Fluid AFI=D1+D2+D3+D4
Index*
Bi-plane Volume (D1)(D2)(D3)(0.52)
* 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)."
6 - 2 0
Minimum Value
D-Tol(D)
(D1-Tol(D1))/(D2+Tol(D2))
(D1-Tol(D1)+D2-Tol(D2)+
D3-Tol(D3))/3
2 2 1/2
π{1/2[(D1-Tol(D1))
+D2 ]}
(D2-Tol(D2))
π(D1-Tol(D1))(D2-Tol(D2))/4
2
(π/6)(D1-Tol(D1))(D2-Tol(D2))
D-Tol(D)
2
A-Tol (A)
100(A1-Tol(A1)-A2-
Tol(A2))/(A1+Tol(A1))
100(D1-Tol(D1)-D2-
Tol(D2))/D1+Tol(D1))
D1-Tol(D1)+D2-Tol(D2)+
D3-Tol(D3)+D4-Tol(D4)
(D1-Tol(D1))(D2-Tol(D2))
(D3-Tol(D3))(.52)
Maximum Value
D + Tol(D)
(D1+Tol(D1))/(D2-Tol(D2))
(D1+Tol(D1)+D2+
Tol(D2)+D3Tol(D3))/3
2
π{1/2[(D1+Tol(D1))
+
2 1/2
]} (D2+Tol(D2))
π(D1+Tol(D1))
(D2+Tol(D2))/4
2
(π/6)(D1+Tol(D1))
(D2+Tol(D2))
D+Tol(D)
A+Tol(A)
100(A1+Tol(A1)-
A2+Tol(A2))/(A1+Tol(A1))
100(D1+Tol(D1)-
D2+Tol(D2))/(D1+Tol(D1))
D1+Tol(D1)+D2+Tol(D2)+
D3+Tol(D3)+D4+Tol(D4)
(D1+Tol(D1))(D2+Tol(D2))
(D3+Tol(D3))(.52)
[ 1 ] I N S T R U C T I O N S
2
+
2 1/2
]}
2
F O R U S E