Subjective discomfort in children receiving 3 T MRI and experienced adults' perspective on children's tolerability of 7 T: a cross-sectional questionnaire survey

Abstract

Objectives: To explore the possible discomfort perceived by children participating in 7 T MRI research, and the age range in which children are most likely to tolerate it well.

Design: A cross-sectional survey using age-appropriate questionnaires containing six measures of subjective discomfort (general discomfort, dizziness, noisiness, claustrophobia and feeling of cold or warm).

Setting: For children, 3 T clinical scanner in a tertiary referral teaching hospital; for adults, 3 and 7 T scanner in a university research building.

Participants: Non-sedated children and young people under 18 years of age who underwent 3 T clinical MRI for brain or musculoskeletal scans and adult volunteers attending 7 T with or without 3 T for brain scans.

Results: 83% (89/107) of involved individuals returned questionnaires. The most common discomfort among 31 children receiving 3 T MRI was noisiness (39%), followed by cold (19%), general discomfort (16%), dizziness (13%) and claustrophobia (10%). The noise was reported more frequently in children younger than 12 years than those older (p=0.021). The most common discomfort for 58 adults receiving 7 T MRI was noisiness (43%). In adults, there was a higher frequency of general discomfort during 7 than 3 T scans (p=0.031). More than 85% of adult respondents thought children aged 12-17 years would tolerate 7 T scans well, but only 35% and 15% thought children aged 10-11 and 8-9 years, respectively, would.

Conclusions: Noisiness was the most common discomfort across all ages in 3 and 7 T scanners. Although general discomfort was more common during 7 than 3 T scans in adults, most adults thought children aged 12 years or more would tolerate 7 T MRI well. Cautious enrolment of children in 7 T MRI study is warranted, but until there is more evidence of how well those aged 12 years or more tolerate 7 T MRI, we would caution against enrolling younger children.

Figure 1

The subjective discomforts reported by children aged 7–11 years (n=10) and 12–17 years (n=21) undergoing 3 T clinical MRI. Thirty-one children reported discomfort in six domains using a five-point Likert scale: ‘yes very’; ‘yes a little’; ‘so-so’; ‘no not really’; ‘no not at all’. Histograms show % reporting discomfort as ‘yes very’ (light grey) and ‘yes a little’ (dark grey). *Younger children reported noise discomfort significantly more often than older children, p=0.021.

Figure 2

The subjective discomforts reported by adults who underwent both 3 and 7 T research MRI. Twenty-six adults reported discomfort in six domains using a five-point Likert scale: ‘yes very’; ‘yes a little’; ‘not sure’; ‘no not really’; ‘no not at all’. Histograms show % reporting discomfort as ‘yes very’ (light grey) and ‘yes a little’ (dark grey). *Adults found the 7 T MRI generally more uncomfortable than the 3 T MRI, p=0.031.

Figure 3

The opinions of experienced adults on whether children ‘would feel ok’ undergoing 7 T MRI. Twenty-six adults who had undergone both 3 and 7 T research MRI reported how, in their opinion, children aged 16–17, 12–15, 10–11 and 8–9 years would feel undergoing 7 T research MRI. Histograms show % reporting the views as ‘yes definitely’ or ‘yes probably’ (black), ‘not sure’ (light grey), and ‘no probably not’ or ‘no definitely not’ (dark grey).