Discrepancy Between Peripheral Nerve Chronaxie Times as Measured Using Electric and Magnetic Stimuli
Scholl T, Chronik B, Collins C, Recoskie B
University of Western Ontario
Peripheral nerve stimulation (PNS) results from induced electric fields during MRI.It is expected that electric field exposure thresholds would be consistent with changing magnetic field exposure thresholds. This assumption has motivated the use of electric field exposure criteria to guide magnetic field exposure criteria in MRI. This study tests this hypothesis by comparing chronaxie times for electric and magnetic strength-duration curves for twenty healthy individuals. The average chronaxie times for the electric and magnetic field conditions were significantly different. This suggests that it is not appropriate to use electric field exposure criteria to guide PNS safety standards in MRI.