Diffusion tensor imaging in attention deficit/hyperactivity disorder: A systematic review and meta-analysis

Diffusion tensor imaging (DTI) allows in vivo examination of the microstructural integrity of white matter brain tissue. A systematic review and quantitative meta-analysis using GingerALE were undertaken to compare current DTI findings in patients with ADHD and healthy controls to further unravel the neurobiological underpinnings of the disorder. Online databases were searched for DTI studies comparing white matter integrity between ADHD patients and healthy controls. Fifteen studies met inclusion criteria. Alterations in white matter integrity were found in widespread areas, most consistently so in the right anterior corona radiata, right forceps minor, bilateral internal capsule, and left cerebellum, areas previously implicated in the pathophysiology of the disorder. Current literature is critically discussed in terms of its important methodological limitations and challenges, and guidelines for future DTI research are provided. While more research is needed, DTI proves to be a promising technique, providing new prospects and challenges for future research into the pathophysiology of ADHD.

► We provide a systematic review and meta-analysis of current literature on DTI in ADHD.
► ADHD patients show widespread abnormalities in brain white matter integrity.
► Affected white matter is consistently found in the right frontal lobe, bilateral internal capsule, and left cerebellum.
► White matter abnormalities are consistent with fronto-striatal-cerebellar deficits.
► We discuss limitations of the current literature and provide guidelines or future DTI research.