A comparative study of numerical and experimental evaluation of RF-induced heating for an endovascular stent-graft at 1.5T and 3T

The radiofrequency (RF) electromagnetic (EM) environment generated in the bore of a magnetic resonance imaging (MRI) scanner may induce power deposition in the surroundings of metallic implants worn by patients. This heating, which may in turn lead to local increases in tissue temperature, is usually quantified in terms of a specific absorption rate (SAR). SAR values in the vicinity of an implant are, in fact, directly linked to high temperature increases at the object [1]. This effect is investigated in this work by comparing simulated SAR peak values near an endovascular stentgraft with experimental measurements of temperature rise. The study was performed at nominal static magnetic fields of 1.5 and 3 T, which correspond to operating frequencies of nominal 64 and 128 MHz, respectively.