Abstract
Purpose :
To investigate the ability of the Rabin Cone Contrast Test (RCCT) to identify clinically meaningful color vision deficiencies in ocular pathologies. Clinical interest include optic neuropathies (traumatic, compressive, inflammatory and ischemic). In addition, we aim to investigate the sensitivity, reliability and reproducibility of color vision (CV) in both normal subjects and the aforementioned disease subjects as measured by the RCCT compared to American Optical Hardy Rand Rittler (HRR) Color Vision Testing.
Prior use of the RCCT has been studied in healthy airforce pilots for entry exam and in glaucoma research. The prevalence and longitudinal changes in color vision defects associated diseases has yet to be investigated using the RCCT.
Methods :
The RCCT is a computerized CVT that allows for a standardized, reproducible exam, with consistent testing conditions and techniques between subjects. Normal and ocular pathology patients who provided signed consent to participate had RCCT testing performed on laptops (Acer Aspire E11 11.5” Laptop Computer) utilizing the Rabin Cone Contrast Testing software and HRR testing.
Results :
The test screens for color vision analysis, quantifies loss of chromatic sensitivity while classifying and grading color deficiency.
The test for both eyes was completed in less than 15 minutes. Photopic display luminance were used to stimulate the cones is specific for cones and eliminates the use of rods under the test conditions.To date, forty eight subjects were enrolled. Twenty eight ocular neuropathy cases who showed decreased color vision in one eye on both HRR tests and quantifyable through the RCCT result was presumed to have an acquired defect. This was the subjects first time taking the computerized RCCT test and subsequent repeat testing at other study timepoints have not been done.
Conclusions :
The program is designed to provide stimulus to each L (long, red), M (medium, green), and S (short, blue) cone individually. With this capability, the RCCT is capable of testing the function of each cone type individually without interference from fellow cone types. Additionally, the photopic display luminance used to stimulate the cones is specific for cones and eliminates the use of rods under the test conditions. The RCCT offers an robust index of color vision that accurately detects type of color vision defecit (CVD) and is capable of grading severity of CVD in clinical ocular pathology.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.