Factors Determining Success of Awake and Asleep Magnetic Resonance Imaging Scans in Nonsedated Children

Effective techniques that allow children to complete magnetic resonance imaging (MRI) scans without sedation are high priority for the imaging community. We used behavioral approaches to scan 64 sleeping infants and toddlers younger than 4 years, and 156 awake children aged 2.5 to 18 years, for a neuroimaging research protocol. Infants and their families participated in a desensitization protocol for several days, then scanning was performed at the child's bedtime during natural sleep. For awake young children, a behavioral protocol was used that included tangible reinforcers, exploration of the scanner environment and a brief practice session. Two scan sessions were targeted for awake children. Success rates by participant were quantified in terms of the proportion of requisite scans in each session that were successfully acquired. The average success rate in sleeping infants and toddlers was 0.461. For awake children aged 2.5 to 6 years, success rates for each session were 0.739 and 0.847. For children aged 7 years and older, success rates were over 0.900 for both the sessions. Overall, though success was lower later in a scan session for both sleeping infants and awake young children, our results demonstrate that it is feasible to collect high-quality imaging data using standard imaging sequences in infants and children without sedation.