Is Fixation Preference a Potential Indicator of Macular Function in Children?

Abstract

Objectives: Fixation preference testing is widely used to detect amblyopia, particularly in preverbal children. Pattern electroretinogram (pERG) is an electrophysiological test which is a sensitive indicator of macular function. The aim of this study was to investigate the relationship between fixation preference and macular function on pERG in children with strabismus. Materials and Methods: The study included 11 children with strabismus. All underwent ophthalmological examination including fixation preference by binocular fixation pattern test, best corrected visual acuity (BCVA) assessment, and pERG. Results: The mean age of the patients was 10.09 +/- 1.18 years. All patients had unilateral fixation. The mean BCVA was 0.85 +/- 0.17 in preferred and 0.48 +/- 0.19 in non-preferred eyes (p=0.003). The mean p50 amplitude was 6.07 +/- 2.06 mu V in preferred and 5.29 +/- 2.20 mu V in non-preferred eyes (p=0.203), and the mean N95 amplitude was 8.27 +/- 2.86 mu V and 8.03 +/- 3.24 mu V respectively (p=0.594). BCVA was correlated with p50 and N95 amplitudes in the non-preferred eyes (p=0.023 and p=0.014). Interocular BCVA difference was correlated with interocular P50 amplitude difference (r=0.688, p=0.019). Conclusion: Although amblyopia is typically considered a cortical phenomenon, future larger studies are needed to investigate the relationship between fixation preference and macular electrophysiological function.