Evaluation of diffusion tensor imaging (dti) imaging findings in children and adolescents with attention deficit hyperactivity disorder and sluggish cognitive tempo-sct

Introduction: Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common mental disorders of childhood with a worldwide prevalence around 3-5% in schoolaged children (Polanczyk et al. 2015). SCT (Sluggish Cognitive Tempo) is a cognitive arousal and alertness disorder that demonstrates clinical symptoms such as confused or seems to be in a fog, daydreams or get lost in his/her thoughts, underactive, slow moving or lacks energy and stares blankly. Most of the previous evidences suggest that SCT is a distinct disorder from ADHD. Objective and Method: The main goal of the current study was to compare diffusion tensor imaging (DTI) findings between Sluggish Cognitive Tempo (SCT) cases comorbid with ADHD and typically developing controls (TD). In this study, 18 SCT cases comorbid with ADHD-combine presentation, 24 SCT cases comorbid with ADHD-Inattentive presentation and 24 TD were evaluated. We applied tract-based spatial statistics to the DTI measures for obtaining fractional anisotropy (FA), axial, radial and mean diffusity (AD, RD, MD) to explore white matter differences for the whole brain. Our main hypothesis is that SCT cases will differentiate from TD in the diffusion tensor imaging findings. Results: Comparing SCT and ADHD-Inattentive presentation with TD, we detected increased FA in the bilateral anterior and posterior limb of internal capsule, bilateral cerebral peduncle and the fornix (p<0.05). Comparing SCT and ADHD-Combine presentation with TD, we did not find any differences for all measures (p>0.05). Discussion: We are not aware of any study that compared these results for SCT cases. Significant differences for the SCT cases may be a preliminary evidence that they have dis- tinct microstructure properties. For ADHD and DTI studies, evaluating comorbidity of SCT may decrease heterogeneity of the findings.