Relative peripheral refraction in school children with different refractive errors using a novel multispectral refraction topographer.

Aim: To compare relative peripheral refraction (RPR) in Chinese school children with different refractive errors using multispectral refraction topography (MRT).

Methods: A total of 713 eyes of primary school children [172 emmetropia (E), 429 low myopia (LM), 80 moderate myopia (MM), and 32 low hypermetropia (LH)] aged 10 to 13y were analyzed. RPRs were measured using MRT without mydriasis. MRT results showed RPR at 0-15° (RPR 0-15), 15°-30° (RPR 15-30), and 30°-45° (RPR 30-45) annular in the inferior (RPR-I), superior (RPR-S), nasal (RPR-N), and temporal (RPR-T) quadrants. Spherical equivalent (SE) was detected and calculated using an autorefractor.

Results: There were significant differences of RPR 15-30 between groups MM [0.02 (-0.12; 0.18)] and LH [-0.13 (-0.36; 0.12)] (<0.05), MM and E [-0.06 (-0.20; 0.10)] (<0.05), and LM [-0.02 (-0.15; 0.15)] and E (<0.05). There were also significant differences of RPR 30-45 between groups MM [0.45 (0.18; 0.74)] and E [0.29 (-0.09; 0.67)] (<0.05), and LM [0.44 (0.14; 0.76)] and E (<0.001). RPR values increased from the hyperopic to medium myopic group in each annular. There were significant differences of RPR-S between groups MM [-0.02 (-0.60; 0.30)] and E [-0.44 (-0.89; -0.04)] (<0.001), and LM [-0.28 (-0.71; 0.12)] and E (<0.05). There were also significant differences of RPR-T between groups MM [0.37 (0.21; 0.78)] and LH [0.14 (-0.52; 0.50)] (<0.05), LM [0.41 (0.06; 0.84)] and LH (<0.05), and LM and E [0.29 (-0.10; 0.68), <0.05]. A Spearman's correlation analysis showed a negative correlation between RPR and SE in the 15°-30° (=0.005), 30°-45° (<0.05) annular (=0.002), superior (<0.001), and temporal (=0.001) quadrants.

Conclusion: Without pupil dilation, values for RPR 15-30, 30-45, RPR-S, and T shows significant differences between myopic eyes and emmetropia, and the differences are negatively correlated with SE.