Chinese researchers have found that a 51-minute 3T magnetic resonance neuroimaging exam with acoustic noise pressure levels of 103.5-111.3 decibels can cause temporary hearing threshold impairment, even in people with a hearing loss. ear protection.
Acoustic noise during MRI is a public health problem and an issue for patients. Numerous reports have shown that sound pressure during a 20-minute MRI scan can impair cochlear function, according to a study published online Feb. 22 in Radiology.
Current MRI guidelines recommend the use of earplugs or earmuffs to reduce acoustic noise in patients, but these precautions are not always effective.
“Despite the use of hearing protection, healthy volunteers who regularly participate in clinical research may have an increased risk of hearing loss, potentially causing a permanent shift in hearing threshold,” wrote corresponding author Jian Yang, PhD, from the Department of Diagnostic Radiology at First. Xi’an Affiliated Hospital of Jiaotong University and colleagues.
In the study, 26 healthy young participants, aged 18 to 30, underwent 3T MRI neuroimaging that included a T-1-weighted 3D gradient echo sequence, a rapid spin echo sequence. T-2 weighted, diffusion tensor imaging, flattening scattering imaging, T-weighted 3D multi-echo gradient echo sequence, and blood oxygen level dependent imaging.
The team used the brainstem auditory response to measure hearing thresholds 24 hours before the imaging procedure, 20 minutes after, and 25 days after the exam.
The results demonstrated a significant increase in the mean threshold shift of 5 decibels plus or minus 8.1 immediately after the MRI scan compared to the baseline study. Brainstem automated auditory response data at day 25 showed no significant difference.
“This finding confirms the importance of appropriate hearing protection in clinical practice,” wrote Yang et al. “In addition, the development of protective devices with a higher level of noise attenuation is desired to reduce the potential risk of hearing loss.”