Infant and Child MRI: A Review of Scanning Procedures

Abstract

Magnetic resonance imaging (MRI) is a safe method to examine human brain. However, a typical MR scan is very sensitive to motion, and it requires the subject to lie still during the acquisition, which is a major challenge for pediatric scans. Consequently, in a clinical setting, sedation or general anesthesia is often used. In the research setting including healthy subjects anesthetics are not recommended for ethical reasons and potential longer-term harm. Here we review the methods used to prepare a child for an MRI scan, but also on the techniques and tools used during the scanning to enable a successful scan. Additionally, we critically evaluate how studies have reported the scanning procedure and success of scanning. We searched articles based on special subject headings from PubMed and identified 86 studies using brain MRI in healthy subjects between 0 and 6 years of age. Scan preparations expectedly depended on subject’s age; infants and young children were scanned asleep after feeding and swaddling and older children were scanned awake. Comparing the efficiency of different procedures was difficult because of the heterogeneous reporting of the used methods and the success rates. Based on this review, we recommend more detailed reporting of scanning procedure to help find out which are the factors affecting the success of scanning. In the long term, this could help the research field to get high quality data, but also the clinical field to reduce the use of anesthetics. Finally, we introduce the protocol used in scanning 2 to 5-week-old infants in the FinnBrain Birth Cohort Study, and tips for calming neonates during the scans.

Dear reviewers: Responses to common reviewer critiques about infant neuroimaging studies

“…In contrast to older participants, most infants are primarily scanned during natural sleep ( Copeland et al, 2021 , Dean et al, 2013 , Mathur et al, 2007 ) to minimize motion. Sleep changes the brain’s response to stimuli in both adults and infants ( Dehaene-Lambertz, 2002 , Larson-Prior et al, 2009 , Tagliazucchi et al, 2012 ).…”

A survey of protocols from 54 infant and toddler neuroimaging research labs

“…These difficulties are heightened within specific age groups, with researchers consistently reporting children between the ages of 1 and 3 years as the most difficult age to scan. Data collection challenges in this age range contribute to a dearth of published literature on MRI-based metrics of human brain development 1 to 3 years of age (Copeland et al, 2021).…”

“…As testament to this, several infant and toddler imaging research groups have published valuable recommendations for optimizing MRI imaging protocols to the early human brain (e.g., Antonov et al, 2017;Dubois et al, 2020;Ellis et al, 2020;Howell et al, 2018;Mongerson, Jennings, Borsook, Becerra, & Bajic, 2017;Raschle et al, 2012). A recent review compiled MRI acquisition strategies from published MRI studies on children age 0 to 6 years (Copeland et al, 2021). Review of the field reveals that preferred practices vary across labs and relate to individual experience rather than an external accepted standard.…”

Subcortical brain segmentation in 5-year-old children: validation of FSL-FIRST and FreeSurfer against manual segmentation

“…The maximum scan time was 60 minutes, and the subjects were allowed to stop the scan at any time. For a more detailed description of the study visits, please see (Pulli et al, 2021) and (Copeland et al, 2021).…”