Evaluating Radio Frequency Heating of Vascular Stents at 3 Tesla using a Gel Phantom
Feiglin D, Wasenko J, Szeverenyi N
SUNY Upstate Medical University
Many patients with vascular stents could not be scanned at 3T due to safety concerns. No specific safety data was available from vendors, safety websites, or literature. We initiated an ex-vivo testing program, examining 20-60 mm long stents. Radiofrequency heating tests followed ASTM F2182-02a guidelines. Temperature increased by 2.5 deg at the ends of some stents during an aggressive 15 minute scan. The measurements were converted to SAR values, which correlated to stent length. SAR gains of 4 were observed in long stents. The tested devices were approved as safe for 3T and lower field MRI scans.