1. Objective: Neuroimaging is a method central to the assessment of cerebral development and integrity throughout the lifespan. Acquiring structural magnetic resonance images (MRI) of the brain during early childhood can inform on the rapid maturational changes that occur in the brain during this time, as well as on the impact of acquired injury on the developing brain. However, between birth and 6 years of age, imaging success is limited given the inherent challenges associated with scanning young children (i.e. movements, anxiety). Various preparation procedures may help to improve MRI acquisition success rates in young children (e.g., Thieba et al., 2018). In this pilot project, using a behavioural familiarization protocol for scanning young children without sedation, we describe factors related to successful imaging as well as image outcomes in healthy control (HC) children and how these may be applied to children who sustain TBI. 

2. Participants and Methods: Sixteen typically developing children or children with TBI (8 females, 8 males) aged 36 to 71 months underwent a behavioural MRI familiarization procedure using introductory materials and a play/mock session before attempting structural MRI. Anatomical image quality was quantitatively assessed using the cat12 toolbox running in SPM and Matlab and through visual inspection. Likelihood of success was analyzed using qualitative questionnaires that were completed before the child went into the scanner. Children chose a movie to watch during scanning. 

3. Results: The overall MRI success rate was 77%. Overall, image quality was very high with 92% rated as fair to very good quality.  Of those children who successfully completed the scan, predicted likelihood of success was high or very high prior to the scan (60-80%). In the unsuccessful group, predicted likelihood of success was lower (33-66% no success or little chance of success). 

4. Conclusions: Preliminary results of this pilot study indicate a success rate of 77% following a familiarization procedure which allows for the acquisition of high-quality MRI images in children under 6 years of age without sedation. Success rates may be predicted prior to scanning through interaction with the child and during familiarization. This procedure is currently being applied to the study of mild TBI in young children. Future analyses could include behavioural data in order for better success prediction models. Ultimately, the findings could improve longitudinal follow-up of healthy and brain injured children under 6 years.

Who will make it through? Predicting non-sedated MRI success in young children with and without traumatic brain injury