Subject tolerance of 7 T MRI examinations

Abstract

Purpose: To determine the subjective experiences and the sources of discomfort for subjects undergoing 7 T magnetic resonance imaging (MRI) examinations on a whole-body 7 T system in a hospital setting

Materials and methods: A postscan survey was filled out by 101 healthy subjects who participated in a 7 T examination. All participants answered questions regarding different potential sensations of discomfort including dizziness, claustrophobia, and scanner noise.

Results: Dizziness was reported most frequently, with 34% of subjects experiencing dizziness while moving into the scanner and 30% while moving out of the magnet. Scanner noise was also frequently mentioned as uncomfortable (33% of the subjects). In 11% of the cases a metallic taste was reported. The overall experience was rated by 3% as unpleasant, 51% as neutral, and 46% as pleasant.

Conclusion: The reported side effects are larger than previously reported for lower field strengths. However, overall, 7 T examinations are well tolerated, with only 3% of subjects rating it as unpleasant. These results agree well with previous in-depth studies, and provide further evidence that 7 T MRI would be accepted by patients in clinical practice.

Keywords: 7 T; high field; magnetic resonance imaging; side effects; subject acceptance.