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A. Klerer - One of the best experts on this subject based on the ideXlab platform.
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computerized Color Vision Test based upon postreceptoral channel sensitivities
Visual Neuroscience, 2004Co-Authors: Eriko Miyahara, Joel Pokorny, Vivianne C. Smith, J. Mccartin, K. Caldwell, Ewelina Szewczyk, A. KlererAbstract:An automated, computerized Color-Vision Test was designed to diagnose congenital red-green Color-Vision defects. The observer viewed a yellow appearing CRT screen. The principle was to measure increment thresholds for three different chromaticities, the background yellow, a red, and a green chromaticity. Spatial and temporal parameters were chosen to favor parvocellular pathway mediation of thresholds. Thresholds for the three Test stimuli were estimated by four-alternative forced-choice (4AFC), randomly interleaved staircases. Four 1.5-deg, 4.2 cd/m 2 square pedestals were arranged as a 2 × 2 matrix around the center of the display with 15-minute separations. A trial incremented all four squares by 1.0 cd/m 2 for 133 ms. One randomly chosen square included an extra increment of a Test chromaticity. The observer identified the different appearing square using the cursor. Administration time was ∼5 minutes. Normal trichromats showed clear Sloan notch as defined by log (AY/AR), whereas red-green Color defectives generally showed little or no Sloan notch, indicating that their thresholds were mediated by their luminance system, not by the chromatic system. Data from 107 normal trichromats showed a mean Sloan notch of 0.654 (SD = 0.123). Among 16 Color-Vision defectives Tested (2 protanopes, 1 protanomal, 6 deuteranopes, & 7 deuteranomals), the Sloan notch was between -0.062 and 0.353 for deutans and was <-0.10 for protans. A sufficient number of Color-defective observers have not yet been Tested to determine whether the Test can reliably discriminate between protans and deutans. Nevertheless, the current data show that the Test can work as a quick diagnostic procedure (functional trichromatism or dichromatism) of red-green Color-Vision defect.
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Computerized Color-Vision Test based upon postreceptoral channel sensitivities.
Visual neuroscience, 2004Co-Authors: Eriko Miyahara, Joel Pokorny, Vivianne C. Smith, Ewelina A. Szewczyk, J. Mccartin, K. Caldwell, A. KlererAbstract:An automated, computerized Color-Vision Test was designed to diagnose congenital red-green Color-Vision defects. The observer viewed a yellow appearing CRT screen. The principle was to measure increment thresholds for three different chromaticities, the background yellow, a red, and a green chromaticity. Spatial and temporal parameters were chosen to favor parvocellular pathway mediation of thresholds. Thresholds for the three Test stimuli were estimated by four-alternative forced-choice (4AFC), randomly interleaved staircases. Four 1.5-deg, 4.2 cd/m 2 square pedestals were arranged as a 2 × 2 matrix around the center of the display with 15-minute separations. A trial incremented all four squares by 1.0 cd/m 2 for 133 ms. One randomly chosen square included an extra increment of a Test chromaticity. The observer identified the different appearing square using the cursor. Administration time was ∼5 minutes. Normal trichromats showed clear Sloan notch as defined by log (AY/AR), whereas red-green Color defectives generally showed little or no Sloan notch, indicating that their thresholds were mediated by their luminance system, not by the chromatic system. Data from 107 normal trichromats showed a mean Sloan notch of 0.654 (SD = 0.123). Among 16 Color-Vision defectives Tested (2 protanopes, 1 protanomal, 6 deuteranopes, & 7 deuteranomals), the Sloan notch was between -0.062 and 0.353 for deutans and was
J. Kuchenbecker - One of the best experts on this subject based on the ideXlab platform.
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Untersuchung des Farbsehens bei akuter einseitiger Neuritis nervi optici mittels eines webbasierten FarbsehTests [Investigation of Color Vision in acute unilateral optic neuritis using a web-based Color Vision Test]
2016Co-Authors: J. Kuchenbecker, M. Blum, Friedemann PaulAbstract:BACKGROUND: In acute unilateral optic neuritis (ON) Color Vision defects combined with a decrease in visual acuity and contrast sensitivity frequently occur. This study investigated whether a web-based Color Vision Test is a reliable detector of acquired Color Vision defects in ON and, if so, which charts are particularly suitable. METHODS: In 12 patients with acute unilateral ON, a web-based Color Vision Test ( www.farbsehTest.de ) with 25 Color plates (16 Velhagen/Broschmann and 9 Ishihara Color plates) was performed. For each patient the affected eye was Tested first and then the unaffected eye. RESULTS: The mean best-corrected distance visual acuity (BCDVA) in the ON eye was 0.36 +/- 0.20 and 1.0 +/- 0.1 in the contralateral eye. The number of incorrectly read plates correlated with the visual acuity. For the ON eye a total of 134 plates were correctly identified and 166 plates were incorrectly identified, while for the disease-free fellow eye, 276 plates were correctly identified and 24 plates were incorrectly identified. Both of the blue/yellow plates were identified correctly 14 times and incorrectly 10 times using the ON eye and exclusively correctly (24 times) using the fellow eye. The Velhagen/Broschmann plates were incorrectly identified significantly more frequently in comparison with the Ishihara plates. In 4 out of 16 Velhagen/Broschmann plates and 5 out of 9 Ishihara plates, no statistically significant differences between the ON eye and the fellow eye could be detected. CONCLUSION: The number of incorrectly identified plates correlated with a decrease in visual acuity. Red/green and blue/yellow plates were incorrectly identified significantly more frequently with the ON eye, while the Velhagen/Broschmann Color plates were incorrectly identified significantly more frequently than the Ishihara Color plates. Thus, under defined Test conditions the web-based Color Vision Test can also be used to detect acquired Color Vision defects, such as those caused by ON. Optimization of the Test by altering the combination of plates may be a useful next step.
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investigation of Color Vision in acute unilateral optic neuritis using a web based Color Vision Test
Ophthalmologe, 2016Co-Authors: J. Kuchenbecker, M. Blum, Friedemann PaulAbstract:Hintergrund Bei akuter einseitiger Neuritis nervi optici (NNO) kommt es neben einer Visusminderung und Storung des Kontrastsehens haufig auch zur Farbsehstorung. Mittels eines webbasierten FarbsehTests soll gepruft werden, ob sich dieser auch zur Detektion einer erworbenen Farbsehstorung bei NNO eignet und welche Tafeln dafur besonders geeignet sind.
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Untersuchung des Farbsehens bei akuter einseitiger Neuritis nervi optici mittels eines webbasierten FarbsehTests
Der Ophthalmologe, 2016Co-Authors: J. Kuchenbecker, M. Blum, Friedemann PaulAbstract:Hintergrund Bei akuter einseitiger Neuritis nervi optici (NNO) kommt es neben einer Visusminderung und Störung des Kontrastsehens häufig auch zur Farbsehstörung. Mittels eines webbasierten FarbsehTests soll geprüft werden, ob sich dieser auch zur Detektion einer erworbenen Farbsehstörung bei NNO eignet und welche Tafeln dafür besonders geeignet sind. Methode Bei 12 Patienten mit akuter einseitiger NNO wurde unter definierten Untersuchungsbedingungen zunächst am betroffenen Auge und dann am Partnerauge ein webbasierter FarbsehTest ( www.farbsehTest.de ) mit 25 Farbtafeln (16 Velhagen/Broschmann- und 9 Ishihara-Farbtafeln) durchgeführt. Ergebnisse Der mittlere bestkorrigierte Fernvisus betrug bei den Patienten am NNO-Auge 0,36 ± 0,20 und 1,0 ± 0,1 am anderen Auge. Die Anzahl der falschen Tafeln korrelierte mit dem Visus. Am NNO-Auge wurden insgesamt 134 Tafeln richtig und 166 Tafeln falsch erkannt, während am anderen Auge 276 Tafeln richtig und 24 Tafeln falsch erkannt wurden. Die beiden Blau/gelb-Tafeln wurden am NNO-Auge 14-mal richtig und 10-mal falsch sowie mit dem anderen Auge 24-mal richtig und keinmal falsch erkannt. Die Velhagen/Broschmann-Tafeln wurden mit dem NNO-Auge im Vergleich zu den Ishihara-Tafeln signifikant häufiger falsch erkannt. Es wurden 4 von 16 Velhagen/Broschmann- und 5 von 9 Ishihara-Tafeln ermittelt, die zwischen NNO-Auge und dem Partnerauge keinen statistisch signifikanten Unterschied aufwiesen. Schlussfolgerungen Die Häufigkeit der Anzahl der Fehlertafeln korrelierte mit der Visusminderung. Sowohl Rot/grün- als auch Blau/gelb-Tafeln wurden signifikant häufiger mit dem NNO-Auge falsch erkannt, wobei die Velhagen/Broschmann-Farbtafeln signifikant häufiger als die Ishihara-Farbtafeln falsch erkannt wurden. Der webbasierte FarbsehTest kann unter definierten Untersuchungsbedingungen auch zur Detektion von erworbenen Farbsehstörungen wie bei der NNO eingesetzt werden, wobei noch eine Optimierung des Tests durch eine veränderte Tafelzusammenstellung möglich ist. Background In acute unilateral optic neuritis (ON) Color Vision defects combined with a decrease in visual acuity and contrast sensitivity frequently occur. This study investigated whether a web-based Color Vision Test is a reliable detector of acquired Color Vision defects in ON and, if so, which charts are particularly suitable. Methods In 12 patients with acute unilateral ON, a web-based Color Vision Test ( www.farbsehTest.de ) with 25 Color plates (16 Velhagen/Broschmann and 9 Ishihara Color plates) was performed. For each patient the affected eye was Tested first and then the unaffected eye. Results The mean best-corrected distance visual acuity (BCDVA) in the ON eye was 0.36 ± 0.20 and 1.0 ± 0.1 in the contralateral eye. The number of incorrectly read plates correlated with the visual acuity. For the ON eye a total of 134 plates were correctly identified and 166 plates were incorrectly identified, while for the disease-free fellow eye, 276 plates were correctly identified and 24 plates were incorrectly identified. Both of the blue/yellow plates were identified correctly 14 times and incorrectly 10 times using the ON eye and exclusively correctly (24 times) using the fellow eye. The Velhagen/Broschmann plates were incorrectly identified significantly more frequently in comparison with the Ishihara plates. In 4 out of 16 Velhagen/Broschmann plates and 5 out of 9 Ishihara plates, no statistically significant differences between the ON eye and the fellow eye could be detected. Conclusion The number of incorrectly identified plates correlated with a decrease in visual acuity. Red/green and blue/yellow plates were incorrectly identified significantly more frequently with the ON eye, while the Velhagen/Broschmann Color plates were incorrectly identified significantly more frequently than the Ishihara Color plates. Thus, under defined Test conditions the web-based Color Vision Test can also be used to detect acquired Color Vision defects, such as those caused by ON. Optimization of the Test by altering the combination of plates may be a useful next step.
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Webbasierte Analyse von Stilling-Farbtafeln
Der Ophthalmologe, 2014Co-Authors: J. KuchenbeckerAbstract:Background Color Vision Tests with pseudoisochromatic plates currently represent the most common procedure for the screening of congenital Color Vision deficiencies. By means of a web-based Color Vision Test, new and old Color plates can be Tested for diagnostic quality without major effort. Methods A total of 16 digitized Stilling’s Color plates of the 11th edition from 1907 were included in a web-based Color Vision Test (http://www.farbsehTest.de). The χ^2-Test was used to check whether the Stilling Color plates showed similar results to the nine previously evaluated Ishihara Color plates. Results A total of 518 subjects including101 (19.5 %) female subjects with a mean age of 34.6 ± 17 years, took the web-based Test with the 25 plates. For all participants the range for the correctly recognized plates was between 5.2 % (n = 27) and 97.7 % (n = 506) for the Stilling Color plates and between 64.9 % (n = 336) and 100 % (n = 518) for the Ishihara Color plates. For participants with more than 5 errors (n = 247), the range for correctly recognized plates was between 2.0 % (n = 5) and 98.0 % (n = 242) for the Stilling plates and between 42.5 % (n = 105) and 100 % (n = 247) for the Ishihara plates. Taking all Color plates and all participants into account there was a significantly higher incidence of erroneous recognition of the Stilling Color plates (3038 false and 5250 true answers) compared to the Ishihara Color plates (1511 false and 3151 true answers) (p
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Visual function Tests on the Internet—sense or nonsense?
American Journal of Ophthalmology, 2005Co-Authors: J. Kuchenbecker, H. LindnerAbstract:background The quantitative capability of the visual system can be Tested using graphic presentations with defined size, form and Color. For presentations, a chart projector or monitor can be used. Today, the number of visual function Tests on the Internet is increasing constantly. methods Options and limitations of visual function Tests using the Internet and the authors’ own Test results are described. results Several visual function Tests, such as visual acuity Tests, the Amsler-Grid, stereo and Color Vision Tests, can already be given via Internet. The variability of the Tests ranges from the simple presentation of graphic elements to the laboriously programmed interactive input by the user to specify the Test result. Under standardized examination conditions, there was a very high correspondence between the results of the authors’ own web-based Color Vision Test and those of luminescence Color Test plates and conventional pigment Color plates. conclusions However, the interpretation of the Test results is difficult due to the absence of controls during the Test as well as the heterogeneity of the hardware. In order to obtain comparable Test results, differences in size and resolution as well as in brightness, contrast and Color of computer monitors must be taken into consideration. Due to the deficits described in the Tests, the value of visual function Tests on the Internet is rather limited. Currently, the data of Test distributers with respect to the Test conditions are all still insufficient. Standards need to be defined for Internet-based visual function Tests. However, visual function Tests on the Internet can achieve Test results comparable to those of conventional visual function Tests under standardized examination conditions in clinical practice. Further studies are needed to check the accuracy of web-based screening examinations in ophthalmology.
Eriko Miyahara - One of the best experts on this subject based on the ideXlab platform.
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computerized Color Vision Test based upon postreceptoral channel sensitivities
Visual Neuroscience, 2004Co-Authors: Eriko Miyahara, Joel Pokorny, Vivianne C. Smith, J. Mccartin, K. Caldwell, Ewelina Szewczyk, A. KlererAbstract:An automated, computerized Color-Vision Test was designed to diagnose congenital red-green Color-Vision defects. The observer viewed a yellow appearing CRT screen. The principle was to measure increment thresholds for three different chromaticities, the background yellow, a red, and a green chromaticity. Spatial and temporal parameters were chosen to favor parvocellular pathway mediation of thresholds. Thresholds for the three Test stimuli were estimated by four-alternative forced-choice (4AFC), randomly interleaved staircases. Four 1.5-deg, 4.2 cd/m 2 square pedestals were arranged as a 2 × 2 matrix around the center of the display with 15-minute separations. A trial incremented all four squares by 1.0 cd/m 2 for 133 ms. One randomly chosen square included an extra increment of a Test chromaticity. The observer identified the different appearing square using the cursor. Administration time was ∼5 minutes. Normal trichromats showed clear Sloan notch as defined by log (AY/AR), whereas red-green Color defectives generally showed little or no Sloan notch, indicating that their thresholds were mediated by their luminance system, not by the chromatic system. Data from 107 normal trichromats showed a mean Sloan notch of 0.654 (SD = 0.123). Among 16 Color-Vision defectives Tested (2 protanopes, 1 protanomal, 6 deuteranopes, & 7 deuteranomals), the Sloan notch was between -0.062 and 0.353 for deutans and was <-0.10 for protans. A sufficient number of Color-defective observers have not yet been Tested to determine whether the Test can reliably discriminate between protans and deutans. Nevertheless, the current data show that the Test can work as a quick diagnostic procedure (functional trichromatism or dichromatism) of red-green Color-Vision defect.
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Computerized Color-Vision Test based upon postreceptoral channel sensitivities.
Visual neuroscience, 2004Co-Authors: Eriko Miyahara, Joel Pokorny, Vivianne C. Smith, Ewelina A. Szewczyk, J. Mccartin, K. Caldwell, A. KlererAbstract:An automated, computerized Color-Vision Test was designed to diagnose congenital red-green Color-Vision defects. The observer viewed a yellow appearing CRT screen. The principle was to measure increment thresholds for three different chromaticities, the background yellow, a red, and a green chromaticity. Spatial and temporal parameters were chosen to favor parvocellular pathway mediation of thresholds. Thresholds for the three Test stimuli were estimated by four-alternative forced-choice (4AFC), randomly interleaved staircases. Four 1.5-deg, 4.2 cd/m 2 square pedestals were arranged as a 2 × 2 matrix around the center of the display with 15-minute separations. A trial incremented all four squares by 1.0 cd/m 2 for 133 ms. One randomly chosen square included an extra increment of a Test chromaticity. The observer identified the different appearing square using the cursor. Administration time was ∼5 minutes. Normal trichromats showed clear Sloan notch as defined by log (AY/AR), whereas red-green Color defectives generally showed little or no Sloan notch, indicating that their thresholds were mediated by their luminance system, not by the chromatic system. Data from 107 normal trichromats showed a mean Sloan notch of 0.654 (SD = 0.123). Among 16 Color-Vision defectives Tested (2 protanopes, 1 protanomal, 6 deuteranopes, & 7 deuteranomals), the Sloan notch was between -0.062 and 0.353 for deutans and was
Jeffery K. Hovis - One of the best experts on this subject based on the ideXlab platform.
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Predicting the CN Lantern Test for Railways with Clinical Color-Vision Tests.
Optometry and vision science : official publication of the American Academy of Optometry, 2020Co-Authors: Ali Almustanyir, Jeffery K. HovisAbstract:SIGNIFICANCE This research will help clinicians in advising their Color-Vision-defective patients regarding their career options. PURPOSE In Canadian railways, individuals with a Color-Vision-defect (CVD) may qualify for positions at shorter sighting distance from signal lights. The railway companies' medical units use the CN Lantern (CNLan) Test, and there is little information available as to whether clinical Color-Vision Tests (CCVTs) can predict the CNLan results. This study determines the ability of some CCVTs to predict the CNLan performance to assist clinicians in advising their CVD patients regarding career options. METHODS The CNLan viewing distance was varied between 4.6 and 0.57 m using a geometric progression. The CCVTs were the Hardy, Rand, and Rittler; Ishihara; ColorDx pseudoisochromatic plate (PIP); the Rabin Cone Contrast Test; Color Assessment and Diagnosis; Cambridge Color Vision Test; U.S. Air Force Operational Based Vision Assessment Cone Contrast Test; Farnsworth Munsell D15; and ColorDx D15. Fifty-six normal-Color-Vision and 63 CVD subjects participated in this study. RESULTS Failure of either the Farnsworth Munsell D15 or ColorDx D15 essentially guarantees failure on the CNLan at the 4.6-m distance. The agreement values decreased as the viewing distance decreased. CONCLUSIONS To counsel patients regarding a career as a locomotive engineer, clinicians should have either the Hardy, Rand, and Rittler or ColorDx PIP and a D15 Test. For patients applying for a position in the yard, a mild-to-moderate classification CVD on HRR or ColorDx PIP indicates a high probability of passing CNLan.
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Simulated night Vision goggle wear and Colored aftereffects.
Aviation space and environmental medicine, 2013Co-Authors: Jeffery K. Hovis, Nicolas PileckiAbstract:BACKGROUND Surveys of military pilots report that between 1.6% and 65% of the respondents experienced altered Color Vision after night Vision goggle (NVG) wear. For the majority of these pilots, the aftereffect was a brownish afterimage that lasted less than 10 min. Given the large disparity in the surveys, we asked subjects to wear goggles which simulated NVGs to determine the nature and duration of any Color aftereffects after removing the goggles. METHODS Two separate experiments were conducted after wearing the goggles for 30 continuous minutes. The first measured the adaptation effects on Color appearance by determining the spectral locations of unique blue and unique yellow. The second measured the adaptation effects on Color discrimination using the Lanthony Desaturated D15 (Desat D15) Color Vision Test. RESULTS The location of unique blue shifted to a longer wavelength by 4 nm immediately after removing the goggles and returned to baseline by 12 min post-wear. The unique yellow location was unaffected by the Color aftereffect. In the second experiment, the time to complete the Desat D15 was 13% longer than baseline for the first 6 min post-wear. There was also a decrease in the frequency of errors relative to baseline. Only one subject reported an afterimage in either experiment. CONCLUSIONS The results showed that the Color aftereffects were subtle and unlikely to cause major Color Vision problems. The time course of the Color aftereffect in this experiment resembled short-term adaptation effects.
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Repeatability of the Holmes-Wright type A lantern Color Vision Test.
Aviation space and environmental medicine, 2008Co-Authors: Jeffery K. HovisAbstract:Purpose: Recent studies showing a lack of internal consistency for the Holmes-Wright Type A Lantern (HWA) raise the issue as to whether the lantern Test is repeatable. This study determines the HWA repeatability for several scoring criteria. Methods: There were 78 individuals with normal Color Vision (NCV) and 80 individuals with defective Color Vision (DCV) who were Tested during two separate visits. Three runs of the Test lights were always presented in dim room illumination. An additional dark-adapted run was presented during both visits for a subset of 61 subjects. Repeatability was evaluated for the following pass/fail criteria: the Joint Aviation Requirements, Farnsworth's criterion, the Commission Internationale de l'Eclairage criterion for the HWA, a perfect performance, and the 99 th and 100 th percentile scores of the NCV sample. Results: The NCV agreement for passing both sessions was high, with 96% having a perfect score at both sessions. The DCV agreement for passing both sessions was lower, ranging from 0.62 to 0.80. Criteria which stopped the Test after a perfect performance on the first run had the lowest values. The DCV agreement for failing both sessions was high, ranging from 0.97 to 0.99. Conclusions: Stopping the Test after a perfect performance on the first run should be abandoned. Presenting three runs of the nine Test lights and allowing no more than two errors is repeatable, passes all the NCV, and minimizes the number of individuals who pass the lantern at the first session and fail at a later session.
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The validity of the University of Waterloo Colored Dot Test for Color Vision Testing in adults and preschool children.
Optometry and vision science : official publication of the American Academy of Optometry, 2002Co-Authors: Jeffery K. Hovis, Susan J. Leat, Sonja Heffernan, Karen EppAbstract:PURPOSE Most Color Vision Tests require a high level of cognitive ability and as such are problematic for preschool children and multiply challenged individuals. Our goal was to design a Color Vision Test for these groups and evaluate the clinical utility for preschool children. METHODS The University of Waterloo Colored Dot Test (UWCDot) for Color Vision Testing requires the subject to distinguish a Colored disc from seven gray discs. The target disc was a Munsell Color along the deutan, protan, or tritan confusion line with gray. The first phase estimated the sensitivity and specificity of the Test for adults. Thirty-one adults with normal Color Vision and 21 adults with congenital red-green defects participated. In the second phase, the utility of the UWCDot Test for screening preschool children was determined. Subjects were 281 males and 269 females aged 2.5 to 5 years with normal Vision. Their Color Vision was also assessed with the Standard Pseudoisochromatic Plates, Part 1 (SPP1). RESULTS The sensitivity and specificity of UWCDot for adults approached the values for the desaturated D-15 when subjective responses were scored. Monitoring fixational eye movements produced sensitivity and specificity values that were similar to the anomaloscope. After adjusting the scoring criterion for the preschool children by using the females as a control, 2.9% of the males were identified as red-green deficient, 1.8% were blue-yellow deficient, and 3.2% had an unclassified deficiency. By definition, 1% of the females failed the Test. Counting fixational eye movements was not a useful scoring method in the preschool children. Comparisons with SPP1 indicated that the UWCDot uncovers approximately 35% of the individuals with definite red-green Color Vision defects. CONCLUSIONS Our results indicate that the UWCDot is capable of detecting approximately 35% of the preschool children who have a congenital red-green Color Vision defect. These individuals are likely to have a more severe deficiency.
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A lantern Color Vision Test for the rail industry
American journal of industrial medicine, 2000Co-Authors: Jeffery K. Hovis, David OliphantAbstract:BACKGROUND: Correct identification of wayside signal Colors is critical for safe operation of railway equipment. However, evaluating Color discrimination using just a screening Test may not be occupationally relevant. METHODS: A lantern Test (CNLAN) was designed to provide a functional assessment of Color discrimination for the rail industry. It was validated against a simulated field trial. 81 individuals with normal Color Vision and 74 individuals with congenital red-green defects participated. Color Vision was classified using the Nagel Anomaloscope. RESULTS: Using a criterion based on the worst-normal performance, 97% of the individuals with a Color Vision defect failed both the CNLAN and simulation trial. This value is slightly lower than the 100% who failed both the Ishihara Test and simulation. However, the Ishihara Test also failed 3.7% of the Color-normals who passed both the simulation and lantern, whereas by definition none of the Color-normals failed the lantern. CONCLUSIONS: This lantern Test provides a reasonable functional assessment of one's ability to identify rail signal Colors; especially when a strict failing criterion is applied to screening Tests. Language: en
David Y. Lee - One of the best experts on this subject based on the ideXlab platform.
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Color changes in the red-green plates of the 50-year-old AO HRR Color Vision Test.
Visual Neuroscience, 2006Co-Authors: David Y. LeeAbstract:The original AO HRR Color Vision Test has been considered by many as one of the best plate Tests. It is still accepted by many governmental agencies for Color Vision certification. In their 1954 publication, Hardy, Rand, and Rittler stated that specially compounded inks were used for printing to avoid Color changes with time. Fifty years later, it is both important and interesting to determine whether the wear and tear cause significant Color changes. The chance finding of a never-used second edition offers an opportunity to evaluate the Color changes. A GretagMacbeth Spectrolino spectrophotometer was used to measure the chromaticities of the never-used book, and an extensively used book. Four plates (#4, 7, 13, 16), selected randomly from the four red-green sections, were analyzed. The Colored dots from each of the eight plates were plotted on a CIE chromaticity diagram. IsoColor lines were drawn to evaluate chromatic alignment. Chromaticities for plates #4 and 7 are significantly different between the two books. With regard to alignment with isoColor lines, the extensively used book is better than the never-used book for plate #4. There is significant misalignment on plate #7 for both books. Chromaticities for plates #13 and 16 are essentially identical between books, all with good alignment with isoColor lines. The overall comparison shows that the chromatic alignment characteristics of the extensively used book are not worse than the never-used book. Since Colors in these plates have to be aligned with both the protan and deutan axes, any significant Color changes would have disturbed this delicate requirement. The findings of many plates with good alignment, and the lack of differences on plates #13 and 16 between books, suggest that there are no significant Color changes over time. Differences between books on plates #4 and 7 were likely the result of the original printing process.
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Evaluation of a new Color Vision Test: "Color Vision Testing made easy".
Optometry and vision science : official publication of the American Academy of Optometry, 1999Co-Authors: Susan A. Cotter, David Y. Lee, Alan L. FrenchAbstract:Purpose. A new pseudoisochromatic Color plate Test, Color Vision Testing Made Easy (r) ' (CVTMET) has recently been introduced. Said to be designed for all age groups, including pre-school children, it uses the identification of simple shapes and objects to detect red-green Color deficiencies. We evaluated the CVTMET to determine if the Test is suitable for Color Vision screening of young children. Methods. Forty-one adults predetermined to be Color normal (n = 20) or to have hereditary red-green Color deficiency (n = 21), served as subjects. A battery of Color Vision Tests including the Ishihara, Panel D-15, and the anomaloscope were used for diagnosis and Color deficiency classification. Subjects were then Tested with Part I and Part II of the CVTMET Test and results were compared to the Ishihara, Panel D-15, and anomaloscope. In addition, the CVTMET was used to screen for Color Vision deficiency in 152 kindergarten children 5 to 7 years of age. Results. The pass/fail results for the adult subjects were the same for Parts I and II and compared favorably with the anomaloscope. There were no false positives (100% specificity) and only a few (2 of 21) false negatives (90.5% sensitivity). The two Color-deficient subjects who passed the CVTMET had the mildest Color deficiencies (simple deuteranomaly) and also passed the Ishihara Test. Testability of kindergarten children was found to be 100%. Color Vision deficiency occurred in 5.06% of the boys, which is about the same frequency found in older boys of similar ethnic background. Conclusion. This preliminary study indicates that the CVTMET appears to be an excellent screening instrument for red-green Color deficiency in adults and has been shown to be useful for examining Color Vision in children 5 to 7 years of age.
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Evaluation of Kojima-Matsubara Color Vision Test plates: validity in young children.
Optometry and vision science : official publication of the American Academy of Optometry, 1997Co-Authors: David Y. Lee, Susan A. Cotter, Alan L. FrenchAbstract:Purpose. We examined a pseudoisochromatic Color plate Test by Kojima and Matsubara for young children which uses drawings of familiar objects rather than letters or numbers. First, we evaluated the Test's efficacy as a Color deficiency screener and its validity in classifying the types of Color deficiencies by comparing its results with those from the Moreland anomaloscope. Second, we eliminated the chromatic factor and evaluated the functional ability of young children to perform the task by determining how many correct responses were obtained using modified black/white replicas of the Test plates. Methods. Part 1: Twenty Color-normal and 13 Color-deficient adults were diagnosed and classified with the Ishihara Test, Panel D-15 Test, and anomaloscope. Subjects were then Tested with the Kojima-Matsubara Test and results were compared with those from the anomaloscope. Part 2: Fifty children aged 3 to 7 years were Tested with modified black/white Test plate replicas. The number of correct responses for each plate was determined for five different age groups. Results. Part 1: Among the 20 Color-normal subjects, 18 read all 10 plates correctly and 2 subjects missed 1 of the 10. Only 1 of the 13 Color-deficient subjects exhibited the expected responses for plates 2 to 6 (used for Color deficiency screening). The Color-deficient subjects' responses for plates 7 to 10, which are used to classify red-green defects, were varied and only the protanomalous subjects (n = 2) followed the expected response pattern. Part 2: Of the 10 black/white modified plates, only 2 were correctly identified by all 50 children. The other plates had a recognition rate that ranged from 32 to 98%. Conclusions. Because the response patterns given by most of the Color-deficient adult subjects were different from those in the Test manual, ambiguous results would occur if the Kojima-Matsubara Test were used for Color Vision screening or the diagnosis of Color deficiency. In addition, the difficulty that many of the young children exhibited in identifying the objects in the black/white replica plates suggests that there would be a large number of false positive errors (classifying a Color normal as Color deficient) when using this Test in young children.