MRI noise may cause temporary hearing impairment despite ear protection

Chinese researchers found a 51-minute 3T MR neuroimaging exam with acoustic noise pressure levels of 103.5-111.3 decibels can cause temporary hearing threshold impairment even in those wearing ear protection.

Acoustic noise during MRI is a public health concern and an issue for patients. Many reports have found sound pressure during a 20-minute MRI exam can alter 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 those precautions aren’t always effective.

“Despite the use of hearing protection, healthy volunteers who routinely participate in clinical research may have an increased risk of hearing loss, potentially causing permanent hearing threshold shift,” wrote corresponding author Jian Yang, PhD, with the department of diagnostic radiology at the First Affiliated Hospital of Xi’an at Jiaotong University, and colleagues.

In the study, 26 healthy young participants, ages 18-30 years old, underwent 3T MR neuroimaging that included T-1 weighted 3D gradient-echo sequence, T-2-weighted fast spin-echo sequence, diffusion-tensor imaging, diffusion-kurtosis imaging, T2-weighted 3D multiecho gradient-echo sequence and blood oxygen level-dependent imaging.

The team used auditory brainstem response to measure hearing thresholds 24 hours before the imaging procedure, 20 minutes after and 25 days after the exam.

Results demonstrated a significantly increased mean threshold shift of 5 decibels plus or minus 8.1 immediately after the MR exam compared with the baseline study. Automated auditory brainstem response data at Day 25 showed no significant differences.

“This finding further supports the importance of appropriate hearing protection in clinical practice,” wrote Yang et al. “Furthermore, developing protective apparatus with higher level of noise attenuation is desired for reducing the potential risk of hearing loss.”