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Color LED reflection technology for early detection of keratoconus

Poster Details

First Author: S.Victor Arni THE NETHERLANDS

Co Author(s):    M. Huijbregtse   A. Geerards           

Abstract Details


To investigate the performance of Color LED reflection technology topography in early detection of keratoconus.


Rotterdam Ophthalmic Institute, Rotterdam Eye Hospital Netherlands


Corneal measurements were gathered from 35 normal (N), 30 Keratonus Suspect (KCS) and 30 Keratoconus eyes at the Rotterdam Eye Hospital, Rotterdam, the Netherlands. The Keratoconus and suspect eyes were from patients with Forme-Fruste cases. Cassini (i-Optics, The Hague, The Netherlands) Color LED reflections and Keratron (Optikon, Rome, Italy) Placido ring reflections were used in the study. The instruments were used to measure corneal irregularity using Keratoconus indices: surface irregularity (SRI), surface asymmetry (SAI) and corneal aberrations: Order 8 Zernike convention @ 6mm corneal zone diameter. Median data from 3 repeated measurements were used for comparison. Wilcoxon signed rank test was used to assess significant differences. Measurements were done on the Forme Fruste cases six months later (N = 24, 6 dropout).


The output from the Keratron is comparable with literature which supports the validity of the algorithms used in the study to determine SRI, SAI. Significant difference was found between the Cassini and the Keratron SRI measurements for the suspect and keratoconus group: KCS (1.41 ± 0.28 vs 0.78 ± 0.65, p < 0.0001) and KC (2.23 ± 0.22 vs 1.99 ± 0.37, p = 0.0004). Significant difference was found between Cassini and Keratron coma aberration (3.21 ± 1.09 vs 2.66 ± 0.59 µm, p = 0.0001) of Keratoconus eyes. For all other parameters, no significant differences were found which suggest that the Cassini and the Keratron are interchangeable for measurement of these parameters. There were no statistical differences found between follow-up and baseline measurements of suspect eyes.


Differences found in SRI and coma aberration suggest that the Cassini is more sensitive in measuring corneal irregularity compared to Placido-based technology. Color LED corneal topography may have potential benefits for early detection of Keratoconus. Validation by a longitudinal study may require more than 6 months to sufficiently show advantage for early detection of Keratoconus. FINANCIAL INTEREST: One of more of the authors... is employed by a forNONEprofit company with an interest in the subject of the presentation

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