Abstract

Aim: This study aimed to investigate macular and optic nerve head (ONH) microvascularization in children diagnosed with attention deficit hyperactivity disorder (ADHD) before and 6 months after the initiation of methylphenidate (MPH) treatment, and to compare these findings with a healthy control group.
Materials and Methods: This retrospective study included 66 eyes of 66 patients with ADHD and 74 eyes of 74 healthy controls, all aged 6–17 years. Participants were grouped as follows: newly diagnosed treatment-naive ADHD patients, the same patients after 6 months of MPH treatment, and healthy controls. Specular microscopy findings, pupil size (PS), anterior chamber depth (ACD), and lens thickness (LT) values of participants were recorded. Additionally, retinal nerve fiber layer (RNFL) thickness, central macular thickness (CMT), and optic nerve head (ONH) radial peripapillary capillary plexus (RPCP), superficial capillary plexus (SCP), and deep capillary plexus (DCP) vessel density (VD) parameters were measured.
Results: Statistically significant increases in whole-image VD values for SCP and DCP were observed following MPH treatment (both p < 0.001). Additionally, SCP VD values were significantly lower in treatment-naive children with ADHD compared to healthy controls, while RPCP VD values were higher (p = 0.006 and p = 0.010, respectively). No statistically significant differences in CMT, RNFL thickness, or anterior segment parameters (PS, ACD, LT) were observed either after MPH treatment within the ADHD group or between the control group and treatment-naive ADHD patients.
Conclusion: In children diagnosed with ADHD, significant increases in SCP and DCP values were observed following MPH treatment. These findings indicate the need for further studies to evaluate the effects and clinical significance of MPH treatment on retinal microvasculature.

Key words: Attention deficit hyperactivity disorder; methylphenidate; optical coherence tomography angiography