GE Senographe 2000 D Operator's Manual page 117

GE Healthcare
REV 1
5. MANUAL MODE
The Manual Mode can be used for standard exposures, implant views, magnified exposures, or for the
examination of the chest wall. See section 3 for additional notes on configuration.
The operator selects the following parameters:
D Focal track (Mo, Rh)
D Filter (Mo, Rh)
D kV
D mAs values
Note: By default, the system selects the large focal spot (0.3) when a standard exam is selected,
and the small focal spot (0.15) when magnification is selected. Exposures are not possible if
these settings are overridden.
Select the desired track/filter configuration according to the thickness and density of the breast to be
examined, then select suitable kV and mAs values.
Note that while the examination of a very dense breast using the rhodium or molybdenum tracks
provides similar contrast images, the same breast examined via the rhodium track benefits from better
tissue visualization and a lower average glandular dose.
Refer to Table 1 below (Suggested Manual Techniques) for suggested parameter selections according
to breast type and thickness.
Table 2 (Maximum and recommended kV ranges) lists the available maximum and recommended kV
ranges.
For thick (>6 cm) or dense breasts, the Mo/Rh and Rh/Rh configurations may provide equivalent or
better image quality with reduced patient dose.
As subject contrast depends on kV values used, note that an increase in the kV value may reduce the
radiation dose to the patient. Potential contrast losses will be handled by digital image processing.
A reduction in the kV value improves contrast but increases the radiation dose to the patient.
In manual mode, the choice of priority to dose reduction or to the desired Signal to Noise Ratio is left
to the discretion of the operator.
Note: If the operator selects an incorrect configuration (filter selection error), the system selects an
authorized configuration and automatically changes the filter. A warning message appears
on the first line of the readout.
Senographe 2000 D Acquisition System
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