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'''Schenck et al. 1992''' PMID 1518472
'''Schenck et al. 1992''' PMID 1518472
A survey of technicians at GE who had worked around 1.5 T and 4 T MRI machines over ther previous year.
"A mild level of sensory experiences, apparently associated with motion within the field of the magnet, was reported by some of the volunteers during some of their exposures. A questionnaire regarding sensory effects associated with magnetic resonance scanners and possibly caused by the static magnetic field of these instruments, was given to nine respondents who had experience within both 1.5-T scanners and this 4-T scanner and to another group of 24 respondents who had experience only within 1.5-T scanners. For the sensations of vertigo, nausea, and metallic taste there was statistically significant (p less than 0.05) evidence for a field-dependent effect that was greater at 4 T. In addition, there was evidence for motion-induced magnetophosphenes caused by motion of the eyes within the static field."
"A mild level of sensory experiences, apparently associated with motion within the field of the magnet, was reported by some of the volunteers during some of their exposures. A questionnaire regarding sensory effects associated with magnetic resonance scanners and possibly caused by the static magnetic field of these instruments, was given to nine respondents who had experience within both 1.5-T scanners and this 4-T scanner and to another group of 24 respondents who had experience only within 1.5-T scanners. For the sensations of vertigo, nausea, and metallic taste there was statistically significant (p less than 0.05) evidence for a field-dependent effect that was greater at 4 T. In addition, there was evidence for motion-induced magnetophosphenes caused by motion of the eyes within the static field."
"A few of the subjects commented on mild dizziness or vertigo while entering or exiting the magnet, but there were no significant complaints related to exposure."
"A few of the subjects commented on mild dizziness or vertigo while entering or exiting the magnet, but there were no significant complaints related to exposure."
'''de Vochet et al 2007''' PMID 17290435
Subjects seated right outside a 7T MRI machine to assess effects of stray field on neurobehavioral tests; highest exposure was 1.6 - 2.0 T (but a very high gradient). Deficits in visual tracking were found after head movements in the stray field, which might be secondary to vestibular effects (although no vertigo is reported in this paper).
"As shown, only visual tracking performance … differed significantly (P <.01) between different levels of static magnetic field exposure, and the magnitude of the effect also depended on the magnitude of the exposure (P <.01). Performance of the Pursuit Aiming II-test (P =.09) and the time to complete the line bisection-test (P =.06) showed a trend towards dependence on the magnitude of exposure, with borderline statistical significance. There was also a trend for the average deviance in the line bisection-test to improve with increased exposure (P =.08)....Since this and previous studies suggest that cognitive effects occur particularly in the visual sensory domain, a possible mechanism might be that the widely recognized "vertigo’’ effect of moving in a magnetic field, might interfere with the vestibulo-ocular reflex."