STANDARDIZED EVALUATION OF THE RED, GREEN AND BLUE COLOR SENSE - COMPARISON OF ARRANGEMENT TESTS AND A NEW COMPUTER-AIDED TEST

Background: Computerized colortests offer the possibility of determini ng quantitative color contrast thresholds under standardized condition s. Arrangement tests allow semiquantitative evaluation of the red, gre en and blue color sense. To validate the results of a new computerized test, its results are compared to those of arrangement tests. Patient s and methods: Thirty-five patients with retinitis pigmentosa (RP, mea n age 38.51, +/- 15.14) as well as 30 normal observers (mean age 36.52 , +/- 14.33) were evaluated. The computerized color test COLDEF was us ed, which is a calibrated screen that presents color optotypes on a co lored background. All colors are chosen from three-color confusion axe s of the CIE-Lu'v' color chart (protan, deutan and tritan axis). By a staircase procedure, the colors of the optotype and background were va ried until the observers minimal color contrast threshold is detected. To compare the results of COLDEF with a routine diagnostic tool, the Farnsworth panel D-15 and Lanthony desature test were chosen. The resu lts of the arrangement tests were scored by a categorization scheme. R esults: Normal observers showed no elevated thresholds either in COLDE F nor in the panel tests. In the RP group increased thresholds along t he blue confusion axis could be detected in most cases. Furthermore, C OLDEF showed increased thresholds along the red and green axes in some patients. With the computerized test it is always possible to identif y the color axis concerned. The new test allows a fast and quantitativ e assessment of acquired color vision deficiencies.