Charles Mougenot1,2, Max O. Khler3, Bruno Quesson2, Ari Partanen3, Julia Enholm3, Chrit T. Moonen2, Teuvo Vaara3, Gsta J. Ehnholm3,4
1Philips Healthcare, Suresnes, France; 2Laboratory of Molecular and Functional Imaging, Bordeaux, France; 3Philips Healthcare, Finland; 4Philips Research North America, USA
Reduction of treatment duration during focused ultrasound ablation, with too short cooling period, can in extreme cases may result in skin burns. Near field cumulative heating, where acoustic beam paths overlap, is difficult to predict with standard MR thermal map limited to the monitoring of single sonication duration. However cumulative MR thermal maps could be obtained with correction of baseline drift and transducer displacement susceptibility change. After 9 volumetric sonications performed on pig leg in vivo, the cumulative temperature is 5C higher than standard temperature. As consequence cumulative temperature should be preferably used to detect skin heating.