GE Revolution CT, User Manual

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Table 1: mA adjustment factor
ASiR-V Normal
10% 0.87
20% 0.74
30% 0.63
40% 0.52
50% 0.44
60% 0.35
70% 0.29
80% 0.23
90% 0.18
100% 0.14
For example, if 40% ASiR-V is selected, multiply the mA displayed in the mA control screen by
0.52, as indicated in Table 1 to obtain the new mA for protocol using ASiR-V, that needs to be
entered into the mA field on the mA control screen.
Multiply the Noise Index or manual mA values that were adjusted for an ASiR-V applied protocol
by the adjustment factors in Table 2 .
Use the following factors to return any manual mA values adjusted for ASiR-V to non- ASiR-V
value.
Table 2: Return to a value for a non-ASiR protocol
ASiR Level Return to non-ASiR manual mA value
30% 1.59
40% 1.92
50% 2.29
2.3 Reconstruction
Reconstruction of ASiR-V images involves defining the level of noise reduction desired for the
parameters used for various applications. Image reconstruction is a blending of the original
images and a percentage of an ASiR-V image. There are 10 blending levels available that are
the amount of noise reduction based on the maximum of the 100% image reconstructed with the
original image data. Reconstruction of ASiR-V images can be prescribed retrospectively in
Retro Recon. A New Series should be selected for each reconstruction of the data with ASiR-V
applied so comparisons and identification of series with ASiR-V can be made more easily.
ASiR-V is located on the Primary and secondary recon settings collection. ASiR-V Setup
Selection is 0% to 100%.
Revolution CT User Manual
Direction 5480385-1EN, Revision 1
310 2 ASiR-V