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Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
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Precision of 5 different keratometry devices.

Jonas Vejvad Nørskov Laursen1,2, Peter Jeppesen3, Thomas Olsen3

  • 1Department of Ophthalmology, Aarhus University Hospital, Aarhus C, Denmark. jonaslaursen@dadlnet.dk.

International Ophthalmology
|March 31, 2015
PubMed
Summary
This summary is machine-generated.

The Nidek Autorefractor/Keratometer (ARK) demonstrated the highest precision in measuring corneal power, while the Oculus Keratograph showed the lowest. This comparison aids in selecting accurate keratometry devices for clinical use.

Keywords:
Corneal powerKeratometryMeasurement reliabilityPrecision

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Area of Science:

  • Ophthalmology
  • Optometry
  • Biomedical Engineering

Background:

  • Accurate keratometry is crucial for intraocular lens calculations and refractive surgery planning.
  • Variability in precision among different keratometry devices can impact patient outcomes.

Purpose of the Study:

  • To compare the intersession precision of five commonly used keratometry devices.
  • To identify the most and least precise devices for corneal power measurement.

Main Methods:

  • Corneal power was measured on two separate visits using Nidek TonoRef II ARK, Zeiss IOLMaster 500, Haag-Streit Lenstar LS 900, Oculus Pentacam, and Oculus Keratograph 4M.
  • Precision was assessed by calculating the mean absolute intersession difference (MAD) in diopters (D).
  • Only non-operated eyes were included in the analysis.

Main Results:

  • The Nidek ARK exhibited the lowest mean absolute difference (MAD) at 0.097 D, indicating highest precision.
  • The Oculus Keratograph showed the highest MAD at 0.215 D, signifying the lowest precision.
  • The precision differences between Nidek ARK and Pentacam, Lenstar, and IOLMaster were not statistically significant.

Conclusions:

  • The Nidek TonoRef II Autorefractor/Keratometer offers the highest precision for corneal power measurement among the evaluated devices.
  • The Oculus Keratograph demonstrated the lowest precision, suggesting potential limitations for critical refractive assessments.