GE Revolution CT User Manual page 240

Number
1
2
3
The mA reduction rate on front side of the patient and the mA reduction tube angle are below.
Table 4: mA Reduction Rate for ODM
SFOV
Head, Small Head, Ped Head
Large Body, Medium Body, Small Body,
Ped Body
NOTE: When patient is in prone position, the mA is reduced from the table side, as it is the
direction of the front side of the patient.
ODM effectiveness will be affected by patient centering. ODM is applied relative to the anterior
surface of the patient and is relative to the isocenter of the SFOV. Thus incorrect positioning of
the patient in the AP direction will change effectiveness in the reduction of dose to
radiosensitive organs.
Organ Dose Modulation builds on the SmartmA feature to enable even further patient dose
reduction. By modulating the X-ray tube current as a function of X-ray tube angle, ODM enables
targeted reduction of the X-ray tube current towards the anterior surface of the patient, providing
enhanced dose reduction to radio-sensitive organs of the patient while maintaining overall
image noise.
In a similar way to other AEC features, the effectiveness of ODM is impacted by patient
centering. To realize the expected dose reduction, the patient should be positioned in the center
of the SFOV.
240
Tube current reduction area
Head first
Feet first
Illustration 3:
Description
mA Reduction Rate
(front side)
Up to 30%
Up to 40%
Revolution CT User Manual
Direction 5480385-1EN, Revision 1
mA Reduction Range FWHM
(tube angle)
100
150
2 Scan Theory