In Brief: Magnetic resonance diagnostic devices guidance
This article was originally published in The Gray Sheet
Executive Summary
Magnetic resonance diagnostic devices guidance: Final guidance outlining criteria for significant risk investigations is released by FDA Sept. 29. The one-page guidance lists four operating conditions that would require an investigational device exemption if utilized in patient studies: 1) main static magnetic field greater than four tesla; 2) specific absorption rate greater than four W/kg averaged over the whole body for any period of 15 minutes; or three W/kg averaged over the head for any period of 10 minutes; or eight W/kg in any gram of tissue in the head or torso, or 12 W/kg in any gram of tissue in the extremities, for any period of five minutes; 3) time rate of change of gradient field (dB/dt) sufficient to produce severe discomfort or painful nerve stimulation; and 4) peak unweighted sound pressure level greater than 140 dB or A-weighted r.m.s. sound pressure level greater than 99 dBA with hearing protection in place...