Tungsten and nitinol braided endovascular catheters: an evaluation of heating in 1.5 t

摘要: Purpose Interventional MRI offers the ability to provide soft tissue contrast and functional information in absence of ionizing radiation. However, performing endovascular procedures raises safety concerns due heating from metallic braid incorporated into catheters. Heating tungsten nitinol braided catheters was assessed an vitro model simulating a patient undergoing scan at specific absorption rate (SAR) level 4 W/kg. Materials Methods adjacent with fluoroptic temperature probes placed device tip, 5cm, 10cm, 20cm proximal tip polyacrylamide gel head portion phantom. A 2.8F catheter (Terumo Progreat, Somerset, NJ) 1.9F (eV3 Echelon, Irvine, CA) were serially embedded laterally offset conformation. 5F stainless steel (Cook Beacon Tip Torcon Advantage, Bloomington, IN) used as positive control sensor background gel, well away devices. Endovascular devices immersed 98cm exposed 2-min scanning followed by 8-min without scanning. The length shortened 5cm this cycle repeated until 63cm. MR based on modified fast spin echo imaging 1.5T scanner. Results did not show heating. maximal for occurred 93cm. initial 4.00°C/min rise during 2.32°C. varied along catheter, most 10cm tip. 0.33°C 2.65°C control. Conclusion study provides magnitude focal induced “worst-case” scenario neurovascular procedure. Nitinol displayed substantial when compared device. This showed potential safe use interventional SAR restrictions.