Enhancing the standard operating range of a placido disk videokeratoscope for corneal surface estimation

Alkhaldi, Weaam, Iskander, Robert, Zoubir, Abdelhak M., & Collins, Michael J. (2009) Enhancing the standard operating range of a placido disk videokeratoscope for corneal surface estimation. IEEE Transactions on Biomedical Engineering, 56(3), pp. 800-809.

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Abstract—Corneal topography estimation that is based on the Placido disk principle relies on good quality of precorneal tear film and sufficiently wide eyelid (palpebral) aperture to avoid reflections from eyelashes. However, in practice, these conditions are not always fulfilled resulting in missing regions, smaller corneal coverage, and subsequently poorer estimates of corneal topography. Our aim was to enhance the standard operating range of a Placido disk videokeratoscope to obtain reliable corneal topography estimates in patients with poor tear film quality, such as encountered in those diagnosed with dry eye, and with narrower palpebral apertures as in the case of Asian subjects. This was achieved by incorporating in the instrument’s own topography estimation algorithm an image processing technique that comprises a polar-domain adaptive filter and amorphological closing operator. The experimental results from measurements of test surfaces and real corneas showed that the incorporation of the proposed technique results in better estimates of corneal topography, and, in many cases, to a significant increase in the estimated coverage area making such an enhanced videokeratoscope a better tool for clinicians.

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5 citations in Scopus
4 citations in Web of Science®
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ID Code: 30332
Item Type: Journal Article
Refereed: Yes
Keywords: Adaptive Filtering, Cornea, Keratrometry, Tear film
DOI: 10.1109/TBME.2008.2005997
ISSN: 0018-9294
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
Current > Schools > School of Optometry & Vision Science
Deposited On: 28 Feb 2010 23:50
Last Modified: 08 Jun 2016 05:49

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