Acoustic noise analysis in echo planar imaging: multicenter trial and comparison with other pulse sequences

Area of Science:

• Medical Imaging
• Acoustics
• Radiology

Background:

• Acoustic noise is a significant factor in Magnetic Resonance Imaging (MRI) patient comfort and safety.
• Echo Planar Imaging (EPI) is a widely used fast imaging technique, but its acoustic properties require evaluation.
• Understanding noise levels is crucial for optimizing MRI protocols and patient experience.

Purpose of the Study:

• To assess the acoustic noise levels of EPI across multiple MRI facilities.
• To compare EPI's acoustic noise with other rapid pulse sequences.
• To analyze the spectral characteristics of EPI's acoustic noise.

Main Methods:

• Measured A-weighted root-mean-square sound pressure levels and peak impulse sound pressure levels for EPI.
• Evaluated EPI noise in eleven clinical superconducting MRI systems under identical conditions.
• Compared EPI noise with six other fast pulse sequences and analyzed acoustic noise spectra.

Main Results:

• Significant institutional variability in EPI acoustic noise levels was observed.
• EPI's overall sound pressure levels were comparable to other fast pulse sequences.
• EPI acoustic noise levels were found to be within permissible exposure limits.
• EPI demonstrated significantly higher acoustic noise in the high-octave frequency bands compared to other sequences.

Conclusions:

• Acoustic noise from EPI varies considerably between MRI institutions.
• EPI's acoustic noise profile is similar to other fast MRI sequences, remaining within safe exposure limits.
• The high-frequency acoustic noise of EPI warrants consideration for potential patient discomfort and further research.