GE Healthcare
Senographe DS
Revision 1
Service Information and Procedures Class A 2385072-16-8EN
Job Card CAL A046 - Half-Value Layer Measurement
Page no. 1703
Chapter 9
JC-CAL-A-046.fm
Job Card CAL A046 - Half-Value Layer Measurement
Chapter 9
1
SUPPLIES
None
2
APPLICABILITY
This Job Card applies to the core product. If the system has the CESM option, perform the CESM ver-
sion of this Job Card located in the CESM IM/SIP instead.
3
TOOLS
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calibrated at mammographic X ray beam energies
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Dosimeter support with Radiation Protection Plate
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Two sheets of 0.2 mm and 0.5 mm thickness of 99.9% pure aluminum
, of length and width sufficient
to fully cover the ionization chamber. The stated thickness should be accurate within ±1%,
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Standard 19 x 23 compression paddle
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4
REQUIRED EFFORT
Personnel: 1 Field Engineer
Time: 20 minutes
5
SAFETY PRECAUTIONS
The procedures in this Job Card produce X-rays. Ensure that you take appropriate precautions when
operating with X-rays (for example, stay behind the radiation screen during an X-ray exposure).
6
PREREQUISITES
! Notice:
The Detector must be protected with the
7
INTRODUCTION
The purpose of this procedure is to verify that the Half-value layer of the X-ray beam is adequate to min-
imize patient breast dose, while not so excessive that contrast is lost in the resultant image.
The tube yield is measured for all track/filter/focal spot combinations and the values used for skin dose
computation.
For each spectrum the HVL and tube Yield are determined and stored on the Senographe, for use in the
skin dose and Mean Glandular Dose evaluation.
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The following techniques will be set automatically by the Senographe:
•
The calibration of each configuration (focal spot, track/filter) is independent of the results obtained in
Configuration
Technique
Mo/Mo
26kV/63mAs
Mo/Rh
28kV/56mAs
Rh/Rh
30kV/45mAs