Subjective Symptoms in Magnetic Resonance Imaging Personnel: A Multi-Center Study in Italy

Association between magnetic resonance imaging use and recovery time following concussion: a CARE consortium study

Researchers may implement magnetic resonance imaging (MRI) to evaluate neurophysiological metrics (e.g. connectivity) in athletes with sports-related concussion (SRC). MRI usage has been purported to exacerbate symptoms that mimic SRC symptomatology, possibly influencing recovery. The present study examined MRI use on SRC recovery outcomes in collegiate athletes. Ninety student-athletes (45 with MRI acutely post-SRC, 45 non-MRI) from four collegiate sites were analysed. Multivariable Cox proportional hazard regressions were used to measure the SRC recovery risk [return-to-play (RTP) initiation (RTP-I) and unrestricted RTP] with hazard ratios (HR) and 95% confidence intervals (95% CI). No hazard differences for median days to RTP-I [MRI: 10, interquartile range (IQR) = 7-15; non-MRI: 7 (IQR = 4-9)] were observed (HR = 0.75; 95% CI: 0.28-1.21). No hazard differences for median days to RTP [(MRI: 17 (IQR = 11-60); non-MRI: 12 (IQR = 8-24)] were observed (HR = 0.77; 95% CI: 0.29-1.26). MRI use post-SRC does not affect recovery; researchers/clinicians can employ such a procedure without affecting athlete recovery.

Health effects related to exposure of static magnetic fields and acoustic noise-comparison between MR and CT radiographers

OBJECTIVES

We explored the prevalence of health complaints subjectively associated with static magnetic field (SMF) and acoustic noise exposure among MR radiographers in Sweden, using CT radiographers as a control group. Additionally, we explored radiographers' use of strategies to mitigate adverse health effects.

METHODS

A cross-sectional survey was sent to all hospitals with MR units in Sweden. MR and/or CT personnel reported prevalence and attribution of symptoms (vertigo/dizziness, nausea, metallic taste, illusion of movement, ringing sensations/tinnitus, headache, unusual drowsiness/tiredness, forgetfulness, difficulties concentrating, and difficulties sleeping) within the last year. We used logistic regression to test associations between sex, age, stress, SMF strength, working hours, and symptom prevalence. Data regarding hearing function, work-environmental noise, and strategies to mitigate adverse symptoms were also analysed.

RESULTS

In total, 529 out of 546 respondents from 86 hospitals were eligible for participation. A ≥ 20 working hours/week/modality cut-off rendered 342 participants grouped into CT (n = 75), MR (n = 121), or mixed personnel (n = 146). No significant differences in symptom prevalence were seen between groups. Working at ≥ 3T increased SMF-associated symptoms as compared with working at ≤ 1.5T (OR: 2.03, CI95: 1.05-3.93). Stress was a significant confounder. Work-related noise was rated as more troublesome by CT than MR personnel (p < 0.01). MR personnel tended to use more strategies to mitigate adverse symptoms.

CONCLUSION

No significant differences in symptom prevalence were seen between MR and CT radiographers. However, working at 3T increased the risk of SMF symptoms, and stress increased adverse health effects. Noise nuisance was considered more problematic by CT than MR personnel.

KEY POINTS

• No significant differences in symptom prevalence were seen between MR and CT radiographers. • Working at ≥ 3 T doubled the odds of experiencing SMF symptoms (vertigo/dizziness, nausea, metallic taste, and/or illusion of movement) as compared to working exclusively at ≤ 1.5 T. • Work-related acoustic noise was less well mitigated and was rated as more troublesome by CT personnel than by MR personnel.

Occupational Exposure Assessment of the Static Magnetic Field Generated by Nuclear Magnetic Resonance Spectroscopy: A Case Study

Magnetic resonance (MR) systems are used in academic research laboratories and industrial research fields, besides representing one of the most important imaging modalities in clinical radiology. This technology does not use ionizing radiation, but it cannot be considered without risks. These risks are associated with the working principle of the technique, which mainly involves static magnetic fields that continuously increase—namely, the radiofrequency (RF) field and spatial magnetic field gradient. To prevent electromagnetic hazards, the EU and ICNIRP have defined workers’ exposure limits. Several studies that assess health risks for workers and patients of diagnostic MR are reported in the literature, but data on workers’ risk evaluation using nuclear MR (NMR) spectroscopy are very poor. Therefore, the aim of this research is the risk assessment of an NMR environment, paying particular attention to workers with active implantable medical devices (AIMDs). Our perspective study consisted of the measurement of the static magnetic field around a 300 MHz (7 T) NMR research spectrometer and the computation of the electric field induced by the movements of an operator. None of the calculated exposure parameters exceeded the threshold limits imposed by legislation for protection against short-term effects of acute occupational exposure, but our results revealed that the level of exposure exceeded the action level threshold limit for workers with AIMD during the execution of tasks requiring the closest proximity to the spectrometer. Moreover, the strong dependence of the induced electric field results from the walking speed models is shown. This case study represents a snapshot of the NMR risk assessment with the specific goal to increase the interest in the safety of NMR environments.