Inability of Open-Field Autorefraction to Eliminate Accommodation in Preschoolers.

Abstract

To evaluate the effectiveness of the Shin-Nippon NVision-K 5001 autorefractometer (Rexxam Co. Ltd., Osaka, Japan) (also branded as the Grand Seiko WR-5100K; Grand Seiko Co. Ltd., Hiroshima, Japan) based on the open-field refractometry principle in refractive measurements of preschool children and to determine its ability to eliminate accommodation adequately. The refractive results of 114 preschool children who presented to the ophthalmology outpatient department for screening were evaluated. The measurements were obtained before and after cycloplegia with the Shin-Nippon NVision-K 5001 autorefractometer and after cycloplegia with retinoscopy, which is the gold standard. The results underwent vectorial transformation to produce the spherical equivalent (M) and two Jackson cross-cylinder (J0 and J45) values. All results were then subjected to statistical analysis. The difference between the measurements was evaluated with repeated measures analysis of variance. Included in the study were 106 preschool children (51 boys and 55 girls). The mean age was 5.3 ± 0.9 years (range: 3 to 6 years). Although statistically significantly more myopic results were obtained with non-cycloplegic measurements using the Shin-Nippon NVision-K 5001 autorefractometer (P < .001), no difference was observed in cylindrical values (P > .05). Cycloplegic J0 measurements were significantly lower (P < .001), but no difference was found between J45 values before and after cycloplegia (P > .05). The Shin-Nippon NVision-K 5001/Grand Seiko WR-5100K open-field autorefractometer seems to be inadequate in eliminating accommodation in childhood. Measurements under cycloplegia continue to be the best method to ensure accurate results. [J Pediatr Ophthalmol Strabismus. 2017;54(5):311-318.].