Abstract
Purpose: :
The purpose of this study was to investigate the macular thickness and retinal nerve fiber layer (RNFL) thickness, in relation to the axial length (AL) in amblyopic and normal eyes of children, using spectral domain OCT (SD-OCT).
Methods: :
Included amblyopic and healthy children underwent full ophthalmic and orthoptic examination, volume scanning of the macula and optic disc with SD-OCT (32 b-scans consisting of 512 a-scans, 3D OCT-1000,Topcon) and recording of AL using the IOL master (Zeiss Meditec). The foveal and pericentral retinal thicknesses (RT) and peripapillary RNFL thickness were then calculated using a custom built Matlab (The MathWorks, Inc.) based program.
Results: :
Twenty-four amblyopic patients (14 boys and 10 girls, mean age 7.7 ± 1.9) and 25 healthy children (11 boys and 14 girls, mean age 8.1 ± 1.5) were enrolled in this study. Except for four amblyopic children, a negative correlation was found between the AL and RT (r=0.44 p<.05). After excluding these four patients, in the remaining group of 20 children both the amblyopic and fellow eyes were significant shorter and had thicker pericentral RT compared to control eyes (see Table). No differences were found in the other parameters between the three groups. AL was a significant covariate (p<.01), whereas age and gender were not. After correcting for AL, no significant differences were found between the three groups for all parameters. Using paired testing amblyopic eyes were 0.3 ± 0.4 mm shorter than their fellow eyes, however they did not have significantly different RT and RNFL thickness measurements.
Conclusions: :
In 20 amblyopic children in our study, the thicker pericentral RT as compared to healthy controls seems to be explained by the shorter AL. However, in four amblyopic children an inverse correlation between AL and RT was found. Further research will focus on this finding.
Keywords: amblyopia • retina • nerve fiber layer