Myopic children have central reduction in high contrast multifocal erg response, while adults have paracentral reduction in low contrast response

PURPOSE. To compare the retinal function of myopic children and young adults using the multifocal electroretinogram (mfERG). METHODS. Fifty-two children (aged 9-14 years) and 19 young adults (aged 21-28 years) with spherical equivalent refractive errors ranging from plano to -5.50 diopter (D) were recruited. They were examined using the global flash mfERG at 49% and 96% contrasts. Each local mfERG response was pooled into five concentric rings for analysis. The amplitudes and implicit times of direct components (DC) and induced components (IC) from the global flash response were analyzed. Hierarchical multiple regressions were used to evaluate the influence of refractive error and axial length on the DC and IC responses. RESULTS. Compared with the emmetropes of the same age group, myopic children had a significant reduction in central macular DC response at 96% contrast while the IC response was unaffected, but myopic adults showed significant reductions in paracentral IC amplitudes at 49% contrast. Implicit times for DC and IC responses were unaffected for either group. CONCLUSIONS. Retinal function was unaffected in myopic children, except for the outer retina in the central macular region. In contrast, the inner retinal function was substantially reduced in myopic adults, especially in the paracentral region. This study provides further evidence for different retinal, physiological characteristics in myopic children and myopic adults.