J Korean Ophthalmol Soc.  2009 May;50(5):684-690. 10.3341/jkos.2009.50.5.684.

Comparison of WaveScan Aberrometer Refraction to Subjective Manifest Refraction and Autorefractor

• Park SJ
• Wee WR
• Lee JH
• Kim MK

• KMID: 2212298
• DOI: http://doi.org/10.3341/jkos.2009.50.5.684

Abstract

PURPOSE:To compare the accuracy of myopic refraction using an aberrometer (WaveScan, Visx, Santa Clara, CA, USA) with manifest refraction using retinoscopy and an autorefractor.
METHODS
The medical records of 200 eyes in 100 patients who visited our clinic from February 2005 to February 2007 for refractive surgery were reviewed retrospectively. We compared the refractive errors obtained using an aberrometer, retinoscopy, and an autorefractor (KR-7100, Topcon, Tokyo, Japan). All of the measured refractive errors were converted to power vectors for statistical analysis. The power vectors consisted of the M vector (M), J0 vector (J0), and J45 vector (J45).
RESULTS
The mean sphere was -4.75 diopters (D) and the mean cylinder was -0.66D with retinoscopy. Power vectors of the aberrometer (PVw) were highly correlated with power vectors of retinoscopy (PVr) and the autrorefractor (PVa). The correlation coefficients (R2) between PVw and PVr were 0.960 (M), 0.852 (J0), and 0.679 (J45) and the correlation coefficients between PVw and PVr were 0.963 (M), 0.685 (J0), and 0.516 (J45). Mean differences were -0.247+/-0.412D (M), 0.034+/-0.120D (J0), and -0.017+/-1.07D (J45) between PVw and PVr, and were -0.068+/-0.403D (M), -0.055+/-0.194D (J0), and -0.052+/-0.165D (J45) between PVw and PVa.
CONCLUSIONS
The measurement of refractive errors using a WaveScan aberrometer seems to be reliable and accurate, although some myopic shift was observed.

Keyword

Aberrometer; Autorefractor; Manifest refraction; Refraction

MeSH Terms

Eye
Humans
Medical Records
Refractive Errors
Refractive Surgical Procedures
Retinoscopy
Retrospective Studies
Tokyo

Figure

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  Figure 1. Correlation graphs and correlation coefficients.

Reference

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