Abstract
Purpose: :
The aim of this study was to investigate ocular fundus morphology in children with attention deficit hyperactivity disorder (AD/HD).
Methods: :
Fourty–two children (37 boys, 5 girls; mean age 12 years) with AD/HD participated in the study. Ocular fundus photographs were taken and optic disc, optic cup, and neuroretinal rim area as well as tourtosity of veins and arteries and number of vascular central branching points were analyzed using a specially designed computer assisted digital mapping system. Data were compared with data for 99 healthy Swedish children and adolescents between 3 and 19 years of age and born at term. The ocular fundus variables measured by the digital image analysis were calculated from the mean of the two eye measurements of each child. The hypothesis of no difference in median values between the children with AD/HD and controls, for the different variables mentioned above, was tested by means of the Mann–Whitney’s U–test.
Results: :
We were able to analyze ocular fundus photographs in 38/42 (90%) of the children concerning optic disc, cup, and neuroretinal rim area. Vessel characteristics were analyzed in 34 (81%) children. The children with AD/HD had a significantly smaller optic disc area (median 2.01 mm2; range 1.28–2.69) than seen in the controls (median 2.41 mm2; range 1.55–5.32) (p<0.0001) as well as a smaller neuroretinal rim area (median 1.78 mm2; 1.21–2.48) compared with the controls (median 2.07 mm2; range 1.31–3.86) (p<0.0001). A lower index of tortuosity for arteries in the AD/HD group compared with the controls was also found (AD/HD children: median index 1.07; range 1.04–1.12 v. reference children: 1.09; range 1.04–1.22) (p=0.0002), as was a lower index of tortuosity for veins (AD/HD group: median index 1.06; range 1.03–1.09, v. reference group: 1.06; range 1.03–1.21) (p=0.003). However, no difference was found in the number of central branching points between the two groups.
Conclusions: :
These children with AD/HD presented subtle morphological changes of the optic nerve and the retinal vasculature indicating an early disturbance of the development of of neural and vascular tissues in the central nervous system. A decrease in neuroretinal rim area reflects either a decrease in the number of axons or a reduction in axonal volume in the optic nerve.
Keywords: imaging/image analysis: clinical • comparative anatomy • optic disc