Aims: To investigate visual function and ocular features in children with attention deficit hyperactivity disorder (AD/HD) and establish whether treatment with stimulants is reflected in functioning of the visual system.
Methods: Detailed ophthalmologic evaluations without and with stimulants were performed in 42 children (37 boys) with AD/HD, mean age 12 years, and compared with a reference group (ref; n=50; mean age 11.9 years; 44 boys). For a comparison between two groups, Mann-Whitney's U-test was used for ordered and continuous variables; for dichotomous variables, Fisher's exact test was used. For paired comparison (with and without treatment), sign test was used.
Results: In all, 83% had visual acuity of >0.8 (<0.1 logMAR) without treatment, 90% with stimulants (ref 98%; P=0.032 and n.s., respectively). Heterophoria was found in 29% without, and in 27% with, stimulants (ref 10%; P=0.038 and n.s., respectively) and subnormal stereovision (>60 s of arc) in 26% (ref 6%; P=0.016) without stimulants, and in 27%, with (P=0.014). Abnormal convergence (>6 cm or absent) was noted in 24% (ref 6%; P=0.031) without treatment and in 17%, with (n.s.). Astigmatism (> or =1.0 D) was observed in 24% (ref 6%; P=0.03), and signs of visuoperceptual problems in 21% (ref 2%; P=0.007). We found smaller optic discs (n=8/38) and neuroretinal rim areas (n=7/38) (P<0.0001) and decreased tortuosity of retinal arteries (n=6/34) (P=0.0002) than that of controls.
Conclusions: Children with AD/HD had a high frequency of ophthalmologic findings, which were not significantly improved with stimulants. They presented subtle morphological changes of the optic nerve and retinal vasculature, indicating an early disturbance of the development of these structures.