The Accuracy and Precision Performance of Four Videokeratoscopes in Measuring Test Surfaces

Tang, Wilfred, Collins, Michael J., Carney, Leo G., & Davis, Brett A. (2000) The Accuracy and Precision Performance of Four Videokeratoscopes in Measuring Test Surfaces. Optometry and Vision Science, 77(9), pp. 483-491.

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In this study we evaluated the accuracy and precision of three placido-disk videokeratoscopes (the Keratron, Medmont and TMS) and one videokeratoscope that uses the raster-stereogrammetry technique (PAR-CTS) in elevation topography with six test surfaces. The test surfaces were a sphere, an asphere, a multicurve, and three bicurve surfaces. Each instrument performed well on certain test surfaces, but none of the instruments excelled on all of the surfaces. The results showed high accuracy of the Keratron and Medmont instruments in measuring the sphere, asphere, and multicurve surfaces, but not the bicurve surfaces. The precision of the Keratron and Medmont instruments were high. The TMS and PAR-CTS instruments showed poorer accuracy than the Keratron and Medmont instruments for the multicurve test surface but showed better performance for the bicurve surfaces. The PAR-CTS had the poorest performance in precision of the four instruments. The use of the Noryl spherical test surface instead of polymethyl methacrylate (PMMA) resulted in small differences in the accuracy performance of the placido-disk videokeratoscopes only.

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58 citations in Web of Science®
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ID Code: 3214
Item Type: Journal Article
Refereed: Yes
Additional Information: Self-archiving of the author-version is not yet supported by this publisher.
For more information, please refer to the journal's website (see link) or contact the author. Author contact details:
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Keywords: Corneal Topography/, standards, Comparative Study, Cornea/pathology, Corneal Topography/instrumentation, Humans, Models, Anatomic, Models, Biological, Reproducibility of Results
ISSN: 1538-9235
Subjects: Australian and New Zealand Standard Research Classification > MEDICAL AND HEALTH SCIENCES (110000) > OPTOMETRY AND OPHTHALMOLOGY (111300)
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Current > Institutes > Institute of Health and Biomedical Innovation
Copyright Owner: Copyright 2000 American Academy of Optometry
Copyright Statement: The contents of this journal can be freely accessed online via the journal’s web page (see link) 12 months after publication.
Deposited On: 25 Jan 2006 00:00
Last Modified: 10 Aug 2011 17:46

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