Siemens MAGNETOM Avanto Operator's Manual page 117

Warming of body tissue
MAGNETOM Avanto, MAGNETOM Verio | syngo MR E11
Print No. MR-01501G.621.02.02.02
MR system operation
The Specific Absorption Rate (SAR), expressed as W/kg, serves as a
stress indicator.
Unacceptably high local SAR values may lead to RF burns. High global
SAR values (head, exposed part of the body, whole body) may lead to
overstress the patient's thermoregulation and the cardiovascular
system.
The B1+ rms value (root mean square value of the MR-relevant
component of B1, which is indicated by the "+") is displayed at the
syngo Acquisition Workplace for each sequence and may serve as an
indication of the RF magnetic field intensity. For details and
important notes about the B1+ rms value, please refer to the "SAR
information" section in the
The energy absorbed in the course of the MR measurement warms
the tissue. The heat generated is dissipated by the thermoregulation
mechanisms of the patient, e.g. through increased perspiration and
blood flow.
The body temperature increases if the patient absorbs more energy
per unit of time than can be dissipated through thermoregulation.
The longer this condition lasts, the greater the increase in
temperature.
The increase in core body temperature is usually well below 1°C
during the course of the MR examination (if the SAR limits described
below are maintained). Nevertheless, according to the IEC safety
standard the following temperature limits must be observed.
Operator Manual Scanning.
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