Please use this identifier to cite or link to this item: https://hdl.handle.net/1822/6646

TitleA comparison of the ARK-700A autokeratometer and medmont E300 corneal topographer when measuring peripheral corneal curvature
Author(s)González-Méijome, José Manuel
Jorge, Jorge
Queirós, A.
Almeida, José B.
Parafita, Manuel A.
KeywordsCorneal topography
Peripheral auto-keratometry,
Video-keratoscopy
Corneal topogometry
Eye rotation model
Peripheral fixation
Issue dateSep-2004
PublisherBlackwell Publishing
JournalOphthalmic and physiological optics
Citation"Ophthalmic and physiological optics". ISSN 0275-5408. 24:5 (Sept. 2004) 391-398.
Abstract(s)The purpose of this study was to evaluate if corneal topogometry measurements as taken with the ARK-700A autokeratometer are comparable with those measured by the Medmont E300 videokeratoscope at corresponding locations. METHODS: Central and peripheral radius and eccentricity were measured in 122 right eyes of young normal subjects using autokeratometry and videokeratoscopy, obtained in a random order. RESULTS: Curvature measurements obtained with the ARK700A and Medmont E300 correlated well for the central cornea. Larger differences were observed between peripheral autokeratometry readings and the empirically determined corresponding locations with the videokeratoscope. Correlations between the instruments are inconsistent, resulting in unacceptable confidence intervals. Corneal eccentricity was significantly different between the instruments for the vertical (t = 2.4; p = 0.018) and for the horizontal meridians. In the first case, the difference between the averaged values was not clinically significant, but in the horizontal meridian the AK significantly overestimated eccentricity values (t = -11.5; p < 0.001) with differences which were clinically significant. CONCLUSIONS: Central corneal curvature data obtained by ARK700A and Medmont E300 can be interchanged but the same is not true of peripheral determinations of corneal shape. ARK700A probably measures peripheral corneal shape within an elliptical region between 5 and 7 mm in diameter, with the major axis in the vertical meridian.
TypeArticle
URIhttps://hdl.handle.net/1822/6646
DOI10.1111/j.1475-1313.2004.00203.x
ISSN0275-5408
Peer-Reviewedyes
AccessRestricted access (UMinho)
Appears in Collections:CDF - OCV - Artigos/Papers (with refereeing)

Files in This Item:
File Description SizeFormat 
GONZÁLEZ-MÉIJOME_04_OPO _Corneal Topography and Autokeratometry_.pdf
  Restricted access
73,5 kBAdobe PDFView/Open

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID