Siemens MAGNETOM Skyra, Руководство пользователя, Страница: 57 / 124

19
Siemens AG Healthcare Sector 11/12 MR compatibility data sheet
RF power distribution relevant for assessing exposure to MR
workers
The diagram shows the RF power distribution along the patient axis of the MAGNETOM Skyra
according to the requirements of the IEC 60601-2-33 standard.
The RF field is calculated along the center line starting in the magnet isocenter. The area
shaded in grey indicates the length of the magnet.
The ratio B1(z)
2
/B1(0)
2
provides a worst case estimation of the SAR contribution to a per-
son who is positioned at a distance z from the isocenter. The SAR contribution is relative to
the SAR that is applied to a person in the center of the patient bore.
For example a person standing in front of the system aperture absorbs a maximum of 0.2%
of the RF power which is applied to a patient scanned in the center of the bore.
z [m]
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
0.00001
0.00
0.0001
0.001
0.01
0.1
1
re
la
ti
ve
B
1
(z
)
2
/B
1(0)
2
Magnet isocenter
End of magnet