Patent ID: 9547053
Date: 2017-01-17
CPC Classifications: G01R

Claim:
1. A method for monitoring patient exposure during an examination with a magnetic resonance device, the magnetic resonance device comprising a transmitter device with a high-frequency coil that is actuatable via a plurality of transmission channels, at least two power amplifiers being used to supply power to the plurality of transmission channels, wherein for each transmission channel of the plurality of transmission channels, a narrowband first measuring device configured to measure an amplitude and a phase of a voltage in a defined frequency range around a magnetic resonance frequency and a broadband second measuring device covering a wider frequency range than the first measuring device and configured to record voltage measurement values suitable for determining an overall power are used, the method comprising: determining a coil power loss from the measured amplitude and the measured phase of the first measuring device; determining an overall transmitted power from the voltage measurement values of the second measuring device; determining a specific absorption rate (SAR) value describing a power entering a patient from the coil power loss and the overall transmitted power and comparing the SAR value with at least one limit value; and terminating a transmission operation of the transmitter device when the at least one limit value is exceeded.