MAGNETIC RESONANCE IMAGING - NATIONAL INSTITUTES OF HEALTH CONSENSUS DEVELOPMENT CONFERENCE STATEMENT
Authors not listed · 1987
The 1987 NIH consensus conference established that even beneficial medical RF exposures require systematic safety evaluation.
Plain English Summary
The NIH convened a consensus development conference in 1987 to evaluate the safety and effectiveness of magnetic resonance imaging (MRI) technology. This government report examined the radiofrequency electromagnetic fields used in MRI scanners and their potential health effects on patients. The conference established early safety guidelines for this powerful medical imaging technology.
Why This Matters
This 1987 NIH consensus conference represents a pivotal moment in medical EMF safety evaluation. At a time when MRI technology was rapidly expanding in hospitals, federal health officials recognized the need to systematically assess the radiofrequency exposures patients receive during scans. The reality is that MRI machines generate some of the most intense RF electromagnetic fields humans encounter, with specific absorption rates that can exceed cell phone exposures by orders of magnitude during imaging sequences.
What makes this particularly relevant today is how it demonstrates the government's early recognition that medical RF exposures required careful safety evaluation. The science demonstrates that even beneficial medical technologies using electromagnetic fields warrant ongoing safety assessment. This precedent underscores why consumer EMF devices deserve similar scrutiny, especially given that unlike brief medical procedures, we're exposed to wireless radiation continuously throughout our daily lives.
Finding
A preliminary case-control study of workers exposed to magnetic fields has shown no trends in data suggestive of a dose-response effect or a latency in health effects, but the number of subjects was small and the followup period short.
In their words
“A preliminary case-control study of workers exposed to magnetic fields has shown no trends in data suggestive of a dose-response effect or a latency in health effects, but the number of subjects was small and the followup period short.”
Source
(1987) (1987)Exposure Information
Specific exposure levels were not quantified in this study.
Study Details
Rapidly changing gradient fields can induce significant electric currents in conductive tissues. Recent studies indicate no interference with cardiac function or nerve conduction at 2 to 7 tesla. The exposure levels approved by the FDA, which are below those that would induce neuromuscular stimulation, are believed to provide a wide margin of safety in this respect. Heating may occur in tissues as a result of resistive losses due to alternating magnetic transmissions from radiofrequency coils. High-field scanners are more likely to cause measurable temperature elevations than low-field devices. Although no adverse effects have been observed at FDA-approved absorption rates, care must be taken with infants, elderly patients with impaired heat loss mechanisms, and hyperpyrexic individuals. Pulse sequences should be modified to prevent excessive heat buildup, particularly in warm and humid environments. Caution must be exercised in the MRI examination of patients requiring monitoring and life-support systems, and in patients who are pregnant. Research performed to date does not indicate risks to the fetus, but MRI examination during pregnancy should be performed only if MRI offers a clear advantage over other tests.
Show BibTeX
@article{magnetic_resonance_imaging_national_institutes_of_health_consensus_development_c_g7160,
author = {Unknown},
title = {MAGNETIC RESONANCE IMAGING - NATIONAL INSTITUTES OF HEALTH CONSENSUS DEVELOPMENT CONFERENCE STATEMENT},
year = {1987},
}