Acoustic noise in magnetic resonance imaging: An ongoing issue

Abstract 

Purpose

Acoustic noise creates a problem for both patients and staff within the magnetic resonance (MR) environment. This study qualitatively and quantitatively investigates the acoustic noise levels from two MR systems in one clinical department and demonstrates the adverse effects that the acoustic noise generated in magnetic resonance imaging (MRI) has on a patient's experience of an MRI examination.

Methods

A questionnaire was distributed to consenting patients undergoing one of two specific MR examinations on two MR systems (System A and System B) of varying age and technology in one clinical department. These evaluated the patient's experience during the MRI examination. Physical measurements of the maximum acoustic noise levels produced by each system for various pulse sequences were also recorded using a sound level meter.

Results

The results of the questionnaire survey demonstrated significantly greater tolerance of the acoustic noise levels of System B (mean noise level rating of 2.45 on LIKERT scale) in comparison to System A (mean noise level rating of 3.71 on LIKERT scale) (P=0.001). Significantly lower noise level descriptions were also demonstrated (P=0.01). The maximum recorded sound levels also confirmed that System B was quieter than the System A.

Conclusion

It is has been demonstrated that the acoustic noise generated during an MRI examinations has an adverse effect on the patient experience during the examination. However, new technology has significantly reduced these effects and is improving patient comfort in MRI. It was shown quantitatively that the newer system's advanced gradient technology was quieter than the older system, in terms of the acoustic noise levels associated with a range of common pulse sequences.

Keywords: Acoustic noise levels, Magnetic resonance imaging, Noise reduction, Patient satisfaction, Hearing protection