Abstract
Purpose :
The aim of this work was to compare two color vision tests to assess chromatic discrimination in patients affected with Usher Syndrome, namely the color contrast sensitivity test measured by the Cambridge Colour Test and the Lanthony Desaturated D15.
Methods :
Twenty-four patients (48 eyes), aged from 11 to 58 years (mean age 30.9), affected with Usher syndrome type I (29.2%), type II (66.6%) or type III (4.2%) were tested. Best corrected visual acuity using ETDRS charts (>logMar 0.5), kinetic visual field (>10° central), Lanthony Desaturated D15 panel and Cambridge Colour Test (CCT, Cambridge Research Systems, UK,low vision strategy with TriVector analysis) were performed for each eye on the same day. Each test was compared with a panel of fifteen healthy volunteers. Clinical parameters were subsequently analyzed, using IBM SPSS Statistics software v.21.0.
Results :
Considering the CCT, 7/48 eyes were normal, 7/48 eyes had tritan defect, and 34/48 eyes were defined as multi-axis alterations.
Regarding the Lanthony desaturated D15, 17/48 eyes tested normal, 2/48 eyes had protan defect, 19/48 had tritan defect whereas 10/48 eyes profound abnormalities without any specific axis defect. Abnormalities of these tests were correlated with age and visual acuity. Both tests however defer statistically, with more color defects detected with CCT than the Lanthony D15.
Conclusions :
The outcome allows us to conclude that there is a coherence between the reference examination, 15 HUE, and CCT used for the low visual acuity, in patients affected by Usher syndrome. However, the CCT proved to be more sensitive than 15 HUE in detecting dyschromatopsia.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.