Quantitative susceptibility mapping reveals brain iron deficiency in children with attention-deficit/hyperactivity disorder. A whole-brain analysis

To quantitatively measure and compare the whole-brain iron deposition between attention-deficit/hyperactivity disorder (ADHD) patients and typically developing (TD) children using the quantitative susceptibility mapping (QSM) technique. This study was approved by the institutional review board of our institution (No. [2019]328). Fifty-one patients between 6 and 14 years with clinical diagnosis of ADHD and 51 age- and gender-paired TD children were enrolled. For each participant, the 3D T1 and multi-echo GRE sequence were performed to acquire the whole-brain data with 3.0-T MRI. The QSM maps were calculated using STISuite toolbox. After normalizing the QSM images to MNI space, the voxel-based analysis was used to compare the iron content between the two groups. Pearson's correlation test was used to assess the associations between the iron content and the score of the tablet-PC-based cancellation test, which was done to evaluate the attention concentration level. Iron deficiency was observed in several brain regions in children with ADHD, including bilateral striatums, anterior cingulum, olfactory gyrus, and right lingual gyri. In further correlation analysis, the left anterior cingulum was found to show positive correlation with the symptom severity (r = 0.326, p < 0.05). Our study demonstrated that the iron deficiency in several brain regions might be related with ADHD, which might be valuable for further studies. And QSM might have the potential efficacy in the auxiliary diagnosis of ADHD. Iron deficiency was observed in several brain regions in children with ADHD, which include bilateral striatums, the critical regions in the dopaminergic transmitter system. The iron content in the left ACG may have association with the symptom severity of ADHD. QSM might have the potential efficacy in the auxiliary diagnosis of ADHD.