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A primary task of the eye care professional is determining the refraction, or optical correction, of a patient. The duochrome red-green test is a standard tool for verification of the final refraction. Traditionally, it is recommended for use both prior to and subsequent to determining the cylindrical or astigmatic component of the refraction. In order for it to be effective when used before correcting the cylinder it is necessary that the COLC (Circle of Least Confusion) be on the retina. This study examined whether it is necessarily true that the duochrome response in uncorrected astigmatism will be as trust-worthy as it is with corrected cylinders. The red-green examination was performed monocularly under the following three conditions: a. fully corrected refraction for the subgroup of eyes that had spherical refractions and for the subgroup of eyes with sphero-cylindrical refractions. b. best sphere-only correction without cylinder correction in sphero-cylindrical eyes c. an induced cylinder error in spherical eyes. The interval between the last \"red\" response and the first \"green\" response for the right eyes as a group and separately for the physiological cylinder and induced cylinder correction sub-groups was calculated and compared using a paired, two-tailed t-test. The intervals between \"red\" and \"green\" responses were not significantly different in the population as a whole and in the uncorrected physiological cylinder and induced cylinder subgroups examined. Based on the finding that the interval of red-green equality with fully corrected cylinder and without the cylindrical correction are not significantly different, the red-green duochrome test can indeed be used both before and after cylindrical correction.

The aim of the study was to assess color perception in the Farnsworth-Munsell 100-Hue test in individuals addicted to narcotic substances, and to analyze the acquired color vision disorders, depending on the duration of addiction and abstinence. Ninety-five persons were qualified for the study. All the subjects were divided into 3 groups. Group I (drug addicts) comprised 45 individuals addicted to narcotic substances and nicotine. Group II (smokers) consisted of 30 individuals addicted only to nicotine, and group III (abstinents) included 20 individuals free of addictions. In all the study groups anamnesis, survey, standard ophthalmological examination and the Farnsworth-Munsell 100-Hue test were performed. In the Farnsworth-Munsell 100-Hue test the mean values of total error score (TES) for the purposes of the analysis, expressed in the values of square root (√TES), proved to be significantly higher in group I than in the two other groups (p < 0.001). In group I, the √TES values exceeding critical values of age norms occurred significantly more frequently than in groups II (p < 0.01) and III (p < 0.05). A positive correlation between duration of addiction and the √TES values was indicated (ρ = 0.234, p < 0.05). The longer was the period of abstinence, the lower were the √TES values, indicating the improved ability to distinguish between colors. The Farnsworth-Munsell 100-Hue test proved useful in the detection and assessment of acquired dyschromatopsy induced by narcotic substances. The observed disorders appeared to be dependent on the duration of addiction and abstinence. Med Pr 2016;67(6):777-785.

Purpose: To evaluate the reproducibility of a new colour test, using the Chromatometer CM3. Methods: Twenty healthy subjects were recruited at the Department of Ophthalmology, at the Medical University of Vienna. A total of 40 eyes were tested. Both eyes were tested separately with the Chromatometer CM3. The colour test was repeated after several days. Each time, best-corrected visual acuity was tested using Snellen charts, and colour perception was tested using the Chromatometer CM3. Results: The Chromatometer CM3 showed reproducible results between the two tests at almost every luminosity level. All 4 green-red measurements and 2 blue-yellow brightness measurements showed reproducible results between the first and second tests. Conclusion: The Chromatometer CM3 seems to be an appropriate method to detect changes in colour perception, although the red-green comparison appeared to be more precise than the blue-yellow comparison.

The assessment of color vision is crucial in both fundamental visual research and clinical diagnosis. However, existing tools for color vision assessment are limited by various factors. This study introduces a novel, efficient method for color vision assessment, which is based on a continuous motion tracking task and a Kalman filter model. The effectiveness of this new method was evaluated by assessing the color vision of both color-deficient observers and normal controls. The results from both a small sample ( N  = 29, Experiment 1 ) and a large sample ( N  = 171, Experiment 2 ) showed that color-deficient observers could be perfectly identified within 20 s using the tracking performance. We also compared the new method with a traditional psychophysical detection task to examine the consistency of perceptual noise estimation between the two methods, and the results showed a moderate correlation (Pearson's r  = .59 ~ .64). The results also demonstrated that the new method could measure individuals’ contrast response functions of both red–green and blue–yellow colors (e.g., the L–M and S–(L + M) axes in DKL color space) in just a few minutes, showing much higher efficiency than traditional methods. All the findings from this study indicate that the continuous motion tracking method is a promising tool for both rapid screening of color vision deficiencies and fundamental research on color vision.

Following a major railway accident in Sweden in 1877 and a suspicion that it was caused by colour blindness, Frithiof Holmgren (1831-1897), a Swedish physiologist of Uppsala, devised his colour wool test which was to become the standard method of testing for colour blindness. The front cover illustration shows a derivation of Holmgren's test devised in 1880 by Dr William Thomson (1833-1907) of Jefferson Medical College and consultant at Wills Eye Hospital, Philadelphia.

The HRR pseudoisochromatic plate (pip) test was originally designed as a screening and diagnostic test for color vision deficiencies. The original HRR test is now long out of print. We evaluate here the new 4th edition of the HRR test, produced in 2002 by Richmond Products. The 2002 edition was compared to the original 1955 edition for a group of subjects with normal color vision and a group who had been previously diagnosed as having color vision deficiencies. The color deficient subjects spanned the range of severity among people with red-green deficiencies except for one individual who had a mild congenital tritan deficiency. The new test compared favorably with the original and in at least two areas, outperformed it. Among subjects with deutan defects the classification of severity correlated better with the anomaloscope results than the original; all the subjects who were classified as dichromats on the anomaloscope were rated as “severe” on the new HRR, while those diagnosed as anomalous trichromats were rated as mild or medium on the new test. Among those with moderate and severe defects the new test was highly accurate in correctly categorizing subjects as protan or deutan. In addition, a mild tritan subject made a tritan error on the new test whereas he was misdiagnosed as normal on the original.

The Farnsworth D15 test (D15) was developed for use in occupational guidance. People with significant color deficiency, including all dichromats are expected to fail and people with slight color deficiency are expected to pass. Pass is a circular results diagram and fail an interlacing pattern with one or more red-green isochromatic errors (Farnsworth, 1947). The Nagel anomaloscope is a “gold standard” reference test for identifying and classifying red-green color deficiency. The matching range on the red/green mixture scale indicates the severity of the discrimination deficit. Pass/fail results for the D15 are presented for 107 protanomalous and 410 deuteranomalous trichromats and compared with the anomaloscope matching range. Thirty-six percent of the subjects examined failed the D15. Protanomalous trichromats are able to utilize perceived luminance contrast to obtain good results on the D15 but 42% of these subjects failed the D15 compared with 35% of deuteranomalous subjects. Failure of the D15 was clearly related to the Nagel matching range in deuteranomalous trichromatism but not in protanomalous trichromatism. For example, 84% of deuteranomalous subjects with matching ranges > 30 scale units failed the D15 but only 2% with matching ranges < 9 scale units were unsuccessful. In comparison, 53% of protanomalous subjects with matching ranges > 15 scale units and 33% of subjects with matching ranges < 5 scale units were unsuccessful. Protanomalous trichromats with apparently minimal color deficiency are therefore shown to have poor practical hue discrimination ability as measured with this test.

Purpose To better understand the reference values and adequate discrimination values of colour vision function with described quantitative systems for the Lanthony desaturated D-15 panel (D-15DS). Methods A total of 1042 Japanese male officials were interviewed and underwent testing using Ishihara pseudoisochromatic plates, standard pseudoisochromatic plates part 2, and the D-15DS. The Farnsworth–Munsell (F–M) 100-hue test and the criteria of Verriest et al were used as definitive tests. Outcomes of the D-15DS were calculated using Bowman's Colour Confusion Index (CCI). The study design included two criteria. In criterion A, subjects with current or past ocular disease and a best-corrected visual acuity less than 0.7 on a decimal visual acuity chart were excluded. In criterion B, among subjects who satisfied criterion A, those who had a congenital colour sense anomaly were excluded. Results Overall, the 90th percentile (95th percentile) CCI values for criteria A and B in the worse eye were 1.70 (1.95) and 1.59 (1.73), respectively. In subjects satisfying criterion B, the area under the receiver operating characteristic curve was 0.951 (95% confidence interval, 0.931–0.971). The CCI discrimination values of 1.52 or 1.63 showed 90.3% sensitivity and 90% specificity, or 71.5% sensitivity and 95% specificity, respectively, for discriminating acquired colour vision impairment (ACVI). Conclusion We provided the 90th and 95th percentiles in a young to middle-aged healthy population. The CCI is in good agreement with the diagnosis of ACVI. Our results could be helpful for using D-15DS for screening purposes.

Primary congenital glaucoma is a rare disease that occurs in early birth and can lead to low vision. Evaluating affected children is challenging and there is a lack of studies regarding color vision in pediatric glaucoma patients. This cross-sectional study included 21 eyes of 13 children with primary congenital glaucoma who were assessed using the Farnsworth D-15 test to evaluate color vision discrimination and by spectral domain optical coherence tomography to measure retinal fiber layer thickness. Age, visual acuity, cup-to-disc ratio and spherical equivalent data were also collected. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were measured and compared based on color vision test performance. Four eyes (19%) failed the color vision test with diffuse dyschromatopsia patterns. Only age showed statistical significance in color vision test performance. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were similar between the color test outcomes dyschromatopsia and normal. While the color vision test could play a role in assessing children with primary congenital glaucoma, further studies are needed to correlate it with damage to retinal fiber layer thickness.

Color deficiency is a common inherited disorder affecting 8% of Caucasian males with anomalous trichromacy (AT); it is the most common type of inherited color vision deficiency. Anomalous trichromacy is caused by alteration of one of the three cone-opsins' spectral sensitivity; it is usually considered to impose marked limitations for daily life as well as for choice of occupation. Nevertheless, we show here that anomalous trichromat subjects have superior basic visual functions such as visual acuity (VA), contrast sensitivity (CS), and stereo acuity, compared with participants with normal color vision. Both contrast sensitivity and stereo acuity performance were correlated with the severity of color deficiency. We further show that subjects with anomalous trichromacy exhibit a better ability to detect objects camouflaged in natural gray scale figures. The advantages of color-deficient subjects in spatial vision performance could explain the relatively high prevalence of color-vision polymorphism in humans.