Ingmar Graesslin1, Sven Biederer2, Bjoern Annighoefer3, Hanno Homann1, Henry Stahl1, Peter Vernickel1, Ulrich Katscher1, Dennis Glaesel4, Paul Harvey5
1Philips Research Europe, Hamburg, Germany; 2University of Lbeck, Lbeck, Germany; 3TU Hamburg-Harburg, Hamburg, Germany; 4Research Establishment for Applied Science, Wachtberg, Germany; 5Philips Healthcare, Best, Netherlands
A comprehensive RF safety concept for parallel transmission MRI systems can be realized by verifying the SAR limits before scanning and monitoring RF signals during scanning. However, using a pre-calculated safety margin over-estimates the actual SAR. This abstract extends the concept of pre-calculated safety margins with a real-time global and local SAR monitoring system. This new concept allows for a significantly increased permissible RF duty cycle and improves the detection of violations of SAR limits or any unsafe condition. The impact of patient motion on SAR is analyzed, and a scan termination in case of unsafe system operation is demonstrated.