Work-related factors associated with occupational exposure to static magnetic stray fields from MRI scanners

Abstract

The study revealed workplace characteristics, scan activities, and personal characteristics associated with SMF and TVMF exposure levels of MRI staff and was able to quantify the unique contribution of each of these factors while adjusting for the presence of others.

Occupational exposure in MR facilities due to movements in the static magnetic field

“…As for peak B measurements, the influence of the probe position on results is less relevant. The peak | B | values reported at 1.5 T and 7 T were slightly higher than literature data only in the case of actions implying the passage of the probe through the bore (A3 and A22, respectively), while the ones at 3 T, not related to movements inside the bore, were lower than those of previous studies …”

“…All these evaluations were conducted with the probe in the same position as in the present study on the head of the subject. In the case of the 1.5 T survey, the comparison with peak |d B /dt| values from other studies is made difficult by the different position of the probe on the body, which affects the nature and the speed of the movements.…”

“…In the last decade, several studies have focused on characterizing work‐related exposure to static magnetic fields and motion‐induced time‐varying magnetic fields from MRI scanners, in order to identify possible related transient and long‐term effects and to assess the actual exposure levels during MRI examinations …”

A survey on abnormal uterine bleeding among radiographers with frequent MRI exposure using intrauterine contraceptive devices

“…Based on the type and strength, each scanner was classified into an exposure category. These categories were based on an extensive measurement survey among MRI technicians . Based on the maximum exposure category of the MRI systems, each participant was then classified into a low, medium, or high exposure‐level category (low = working only with extremity scanners, or with closed‐bore or open‐bore scanners below 1.5 T; medium = working with closed‐bore or open‐bore scanners at 1.5 T; high = working with any scanners stronger than 1.5 T, or with upright scanners).…”

“…In recent decades, MRI scanners have increased rapidly in numbers, use, and field strength (B 0 ); consequently, the number of technicians exposed, as well as exposure to stray static magnetic fields and motion‐induced time‐varying magnetic fields, has increased . A recent case series reported three women working in the radiology department in a hospital in Milan, Italy, with abnormal uterine bleeding , defined here as having either menorrhagia or metrorrhagia or a combination of both: prolonged for 7 or more days, or excessive uterine bleeding of 80 mL or more, occurring at irregular and/or frequent intervals.…”