Correlation of Gene Structure and Psychophysical Measurement in Red-Green Color Vision Deficiency in Chinese

2000 ◽  
Vol 44 (6) ◽  
pp. 596-600 ◽  
Author(s):  
Q Zhang
2016 ◽  
Vol 57 (8) ◽  
pp. 3853 ◽  
Author(s):  
Emily J. Patterson ◽  
Melissa Wilk ◽  
Christopher S. Langlo ◽  
Melissa Kasilian ◽  
Michael Ring ◽  
...  

2019 ◽  
Vol 36 ◽  
Author(s):  
Keiko Sato ◽  
Takaaki Inoue ◽  
Shuto Tamura ◽  
Hironori Takimoto

AbstractPrevious studies have shown that with the use of tinted lenses (or colored filters), individuals with red–green color vision deficiency (CVD) report an improvement in their performance on certain color vision tests. In this context, this study examines the effects of a digitally generated red-colored filter and identifies the mechanism mainly responsible for the changes in red–green CVD observers’ performance on a D-15 arrangement test performed using the filter. We simulate the red filter digitally with the spectral transmittance similar to that of the X-Chrom, which is a red-tinted lens. Fourteen red–green CVD subjects are subjected to the D-15 test on a computer monitor under four filter conditions, consisting of one condition without the filter and three conditions with the filter, corresponding to the opacity of the red filter. The results show that while the simulated red filter improves the performance of deutans to arrange the caps in the D-15 test, this is not the case for protans. In addition, considerations based on the human cone-contrast model enable us to identify that the improvement in deutan observers largely results from the increase in the luminance contrast between stimuli and a background. To summarize, the red filter simulated in this study induces different changes in the red–green CVD observer luminance contrast between the protan and deutan types, with the result that the performance of deuteranopes improves while that of protanopes deteriorates.


2017 ◽  
Vol 15 (2) ◽  
pp. 19-25
Author(s):  
Sabina Shrestha ◽  
Aparajita Manoranjan ◽  
Sushan Man Shresthatha

Introduction: Certain changes occur in high altitude which can be organic, motor or functional. This study was conducted to find out ocular morbidity at high altitude in Nepal.Methods: A cross sectional study was conducted at four different places at altitudes of 2710 m (Jomsom), 2900 m (Kagbeni), 3500 m (Jharkot) and 3800 m (Muktinath) of Mustangdistrict of Nepal using convenient sampling method. A total of 222 subjects (444 eyes) were included. They were examined for vascular engorgement and tortuosity, arteriovenous ratio changes, retinal hemorrhages, cataract, pterygium, color vision and intraocular pressure. The motor changes like esodeviation and exodeviation were studied.Results: Of the total 222 participants, 164 (77.5%) were more than 40 years of age and 58 (22.5%) were less than 40 years. The male to female ratio was 1:1.1. The duration of stay at high altitude was >10 years in 96.6%, >15 years 88.3% and >20 years 83.8%. The prevalence of cataract was 19.8% and pseudophakia 17.1%. Other organic changes like venous engorgement, arterio-venous ratio changes and venous tortuosity was also found at high altitude. There was no significant change in intraocular pressure at high altitude. Esodeviation was present in 14%. The prevalence of pterygium was present in 39.6%. Similarly, the prevalence of red green color vision deficiency was 45.1%.Conclusion: Cataract, pterygium, red green color vision deficiency, esodeviation, venous engorgement and venous tortuosity were found to be prevalent at high altitude of Nepal.


2015 ◽  
Vol 21 (2) ◽  
pp. 279-289 ◽  
Author(s):  
Douglas R. Keene

Abstract“Color blindness” is a variable trait, including individuals with just slight color vision deficiency to those rare individuals with a complete lack of color perception. Approximately 75% of those with color impairment are green diminished; most of those remaining are red diminished. Red-Green color impairment is sex linked with the vast majority being male. The deficiency results in reds and greens being perceived as shades of yellow; therefore red-green images presented to the public will not illustrate regions of distinction to these individuals. Tools are available to authors wishing to accommodate those with color vision deficiency; most notable are components in FIJI (an extension of ImageJ) and Adobe Photoshop. Using these tools, hues of magenta may be substituted for red in red-green images resulting in striking definition for both the color sighted and color impaired. Web-based tools may be used (importantly) by color challenged individuals to convert red-green images archived in web-accessible journal articles into two-color images, which they may then discern.


2019 ◽  
Vol 27 (13) ◽  
pp. 17954 ◽  
Author(s):  
Miguel A. Martínez-Domingo ◽  
Luis Gómez-Robledo ◽  
Eva M. Valero ◽  
Rafael Huertas ◽  
Javier Hernández-Andrés ◽  
...  

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