Scanner Specific Relationship Between Displayed SAR and Heating Adjacent to Deep Brain Stimulation Leads: An in Vitro Study

Robert Dawe¹, Leo Verhagen Metman¹

The guideline for head specific absorption rate (SAR) during MRI of patients with implanted deep brain stimulation (DBS) leads is difficult to interpret because SAR estimation techniques vary among scanner manufacturers. The purpose of this study was to establish a relationship between displayed head SAR and local tissue heating in our particular scanner. Heating of approximately 4.9˚ C per 1.0 W/lb. of displayed head SAR was observed, confirming that potentially dangerous heating of DBS leads is possible. At the same time, the results suggest that the SAR guideline for implanted DBS leads may be overly conservative.