Purchase this article with an account.
V. C. Fan, M. Massingale, M. Vallabhajosyula, P. A. Asbell; A Comparison of the Marco/Nidek OPD, the Topcon Auto-refractor, and Manifest Refraction in the Determination of Best Corrected Spectacle Visual Acuity. Invest. Ophthalmol. Vis. Sci. 2008;49(13):1430. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To compare the accuracy of the Marco/Nidek ARK 10000 (OPD), the Topcon KR3000 Autorefractor (AR) and Manifest Refraction (MR) in terms of sphere, cylinder, and axis.
Each patient underwent 3 automated measurements using the Marco/NIDEK OPD ARK 10000 Scan as well as Topcon KR3000 during the same visit. We recorded the mean of the sphere, cylinder, and axis. Subsequently, these measurements were used as a base to formulate a MR measurement. None of the patients received cycloplegic agents.
Repeatability analysis showed that the initial wavefront refraction was not significantly different from the mean of the three refractions. The absolute value (± standard deviation) of the difference between the initial OPD compared with the MR was 0.46±0.48 diopters (D) for sphere, 0.21±0.26 D for cylinder, and 39.4±63.6 degrees for axis; the difference between initial AR compared with the MR was 0.36±0.37 D for sphere, 0.31±0.33 D for cylinder, 24.9±48.5.for axis. However, the differences between the OPD, the AR, and the MR for sphere, cylinder, and axis were not found statistically significant.
The wavefront-derived OPD values reflect the physical optical system, but not necessarily subjectively derived values, and the impact of this disagreement on patient satisfaction is unknown. Although our clinical suspicion that the OPD was superior to the other AR, our studies indicate that both the OPD and AR are similar in estimating Refractive Error. Future studies with larger numbers evaluating these and other technology and its role in clinical ophthalmology are warranted.
This PDF is available to Subscribers Only