PRELIMINARY COMPARISON OF THREE ACCOMMODATION MICRO FLUCTUATION REPORTING APPROACHES IN OCULAR STABILITY INVESTIGATION

Abstract

Accommodation of micro fluctuation has been the subject of many studies of ocular stability. Although there are three existing micro fluctuation reporting approaches encompassing the standard deviation approach, root means square approach and Fourier transform analysis, the direct comparison of these approaches is lacking. This study aims to descriptively compare the three reporting approaches using a single subject in the initial analysis. Measurement was done on the right eye using an open-field autorefractor (WAM-5500 Grand Seiko Co., Ltd., Japan) via the dynamic mode while looking at a distant target. The standard deviation (SD) approach recorded 0.1723 D accommodation micro fluctuation which was nearly identical to the root means square (RMS) approach of 0.1719 D. As for the Fourier transform (FT) approach, the variation was apparent in the low-frequency but not in the high-frequency component. Additional analysis showed the correlation coefficient between RMS and SD, between FT and SD and between FT and RMS was at 0.5776, 0.4745 and 0.4276, respectively (all P-values <0.01). In conclusion, the accommodation micro fluctuation can be aptly described through the root means square approach as it has fewer errors than the standard deviation approach and is less complicated than the Fourier transform approach.