Prevalence Of Color Vision Deficiency Research Articles

The prevalence of color vision deficiency in the northeast of Iran

PurposeTo determine the prevalence of color vision deficiency (CVD) in the northeast of Iran. MethodsThis cross-sectional, population-based study was conducted in Mashhad, in the northeast of Iran. Multistage cluster sampling was used for selecting the participants. After preliminary screening, the subjects underwent a complete ophthalmic examination. The examination included the measurement of visual acuity, refraction, and slit-lamp biomicroscopy. The Farnsworth D-15 test was used to detect CVD. The color vision test was done with the best optical correction. ResultsOf the 4453 invitees, 3132 participated in the study (response rate: 70.4%). The overall prevalence of CVD in this study was 13.93% [95% confidence interval (CI): 12.44–15.41]. The prevalence of CVD in males and females was 15.85% (95% CI: 13.26–18.44) and 12.96% (95% CI: 11.22–14.71), respectively. The most prevalent types of CVD were tritanopia (6.96%; 95% CI: 5.84–8.08), deuteranopia (3.92%; 95% CI: 3.14–4.70) and tritanomalous (2.21%; 95% CI: 1.55–2.86), respectively. According to the results of logistic regression, the odds of having protanopia were higher in females than males [Odds ratio (OR) = 4.80; 95% CI: 1.20–19.18]. The odds of having deuteranopia were lower in females than males (OR = 0.52; 95% CI: 0.35–0.76). The odds of having CVD were lower in 16–30 (OR = 0.52; 95% CI: 0.37–0.73) and higher in 46–60 (OR: 1.41; 95% CI: 1.01–1.97) year age groups compared to 7–15 year age group. The odds of having tritanopia in 16–30 and 46–60 year age groups was 0.56 (95% CI: 0.35–0.90) and 1.79 (95% CI: 1.19–2.67) compared to 7–15 year age groups, respectively. ConclusionThe prevalence of CVD was high in this study, especially in males and people over 46 years of age. Planning for involvement of ocular disease control programs in health care systems can be helpful in the reduction of CVD and improving the quality of life in affected patients.

Frequency of color blindness in pre-employment screening in a tertiary health care center in Pakistan.

Objective:To describe the frequency of color vision deficiency among Pakistani adults presenting for pre-employment health screening in a tertiary care hospital.Methods:The cross-sectional study was carried out at the Aga Khan University Hospital, Karachi, and the data was collected for color vision deficiency, age, gender, and job applied for from pre-employment examination during 2013-2014. IBM SPSS 20 was used for statistical analysis.Results:Three thousand four hundred and thirty seven persons underwent pre-employment screening during 2013 and 2014; 1837 (53.44%) were males and 1600 (46.65%) females. The mean age was 29.01 (±6.53) years. A total of 0.9% (32/3437) persons had color vision deficiency with male being 1.4% and female 0.4%.Conclusion:Color vision deficiency was observed in 0.9% of candidates screened for pre-employment health check up in a tertiary care hospital. The color vision deficiency was predominantly present in male individuals.

Prevalence of Colour Vision Deficiency (CVD) In Medical Students In Kolkata, West Bengal

Objective: Colour vision is a function of three types of cone pigments present in retina. Any abnormality in the cone pigments may cause deficiency of colour vision which is called as colour blindness. The incidence of Colour vision deficiency varies from race to race and different in different geographical areas. Colour is very important sign used in medical profession, but there is no effective screening for Colour Vision Deficiency (CVD) at any level of medical profession. The present study was undertaken to find out CVD in medical students at different Medical Colleges in Kolkata. Material and Method: A total of 300 medical students including 168 males and 132 females between 18-22 years were examined for CVD in Medical colleges in Kolkata. Each student without ocular abnormality was shown Ishihara's plates under day light at normal reading distance. Results: Among 168 boys, 8 were colour deficient (4.8%), and 46 (27.3%) showed red-green anomaly. Among 132 girls, 46 (34.8%) showed red-green anomaly. Conclusions: With this incidence of colour vision deficiency, students with CVD may feel difficulty in day-today practice in medical field. So, screening for CVD in medical students and medical technicians at the time of selection is very important and that may help for early management of CVD.

Prevalence of Color Vision Deficiency among Medical Students in KFU- SA (2014

Prevalence of Color Vision Deficiency among Medical Students in KFU- SA (2014

Prevalence of color vision deficiency among arc welders

PurposeThis study was performed to investigate whether occupationally related color vision deficiency can occur from welding. MethodsA total of 50 male welders, who had been working as welders for at least 4 years, were randomly selected as case group, and 50 age matched non-welder men, who lived in the same area, were regarded as control group. Color vision was assessed using the Lanthony desatured panel D-15 test. The test was performed under the daylight fluorescent lamp with a spectral distribution of energy with a color temperature of 6500K and a color rendering index of 94 that provided 1000lx on the work plane. The test was carried out monocularly and no time limit was imposed. All data analysis were performed using SPSS, version 22. ResultsThe prevalence of dyschromatopsia among welders was 15% which was statistically higher than that of nonwelder group (2%) (p=0.001). Among welders with dyschromatopsia, color vision deficiency in 72.7% of cases was monocular. There was positive relationship between the employment length and color vision loss (p=0.04). Similarly, a significant correlation was found between the prevalence of color vision deficiency and average working hours of welding a day (p=0.025). ConclusionsChronic exposure to welding light may cause color vision deficiency. The damage depends on the exposure duration and the length of their employment as welders.

Prevalence of color vision deficiency (CVD) and ABO blood groups in Kannur district of Kerala, India.

Colour’s have profound influence in life. Colour vision deficiency (C. V. D), A. B. O & Rh blood groups are inherited entities with different geographical regions, and from race to race it varies. As the C. V. D once occurred cannot be changed in life time.750 cases of Colour Vision Deficiency individuals were examined and were identified and confirmed by testing colour vision of the person by Ishihara's Chart test for both eyes. Those found to be suffering from congenital colour blindness were then subjected to A, B, O & Rh grouping by slide method. Our results showed statistical significant positive relationship between congenital C. V. D individuals and their A, B, O, R, H blood groups. Our aim was to study relationship between A, B, O blood group, Rh factor, G-6PD and to know if any Colour Vision Deficiency (C. V. D) present in this population.

PREVALENCE OF COLOR VISION DEFICIENCY AMONG DENTAL STUDENTS IN ALEXANDRIA, EGYPT

Introduction: The key objective of esthetics in dentistry is to create natural blending, with well-proportioned teeth considering the parameters of surface form, translucency and color. Tooth color is determined either instrumentally or visually. Instrumental color determination of teeth is not error proof. Visual color determination, though subjective, is the most commonly applied method. Consequently, color vision deficiency would fundamentally influence this method. Objectives: The aim of this study was to detect the prevalence of color vision deficiency among dental students in Alexandria, Egypt. Methodology: Four hundred dental students were randomly selected [200 males and 200 females] to participate in this study. An informed consent was obtained and brief instructions were given. To facilitate the scoring and analysis of the results, a key answer sheet was used. Results: The results showed that 4.5% of the males had color vision deficiency; meanwhile none of the females had color vision deficiency. Among the discovered color vision deficient males, 66% were not aware of their condition

Prevalence and gene frequency of color vision impairments among children of six populations from North Indian region

X-linked red–green color blindness is the most widespread form of vision impairment. The study aimed to determine the prevalence and gene frequencies of red–green color vision impairments among children of six different human populations of Jammu province. A total of 1028 healthy subjects (6–15 years of age) were selected from five Muslim populations and the color vision impairments were determined using the Ishihara's test of color deficiency. The gene frequency was calculated using Hardy–Weinberg equilibrium method. The prevalence of color vision deficiency (CVD) ranged from 5.26% to 11.36% among males and 0.00%–3.03% among females of six different populations. The gender based differences in the frequency of CVD was found to be statistically significant (p < 0.0001), with a higher prevalence among male (7.52%) as compared to female (0.83%) children. We observed high frequency of deutan as compared to protan defects. The incidences of deuteranomaly (5.68%) and deuteranopia (2.27%) were higher among male children of Syed population while the frequencies of protanomaly (1.94%), protanopia (1.28%) and achromacy (2.27%) were the highest among male subjects of Khan, Malik and Syed populations, respectively. The allele and genotype frequencies showed cogent differences among six populations. The population based assessment of CVDs help patients to follow adaptive strategies that could minimize the risks of the disease.

Prevalence of Color Vision Deficiency and its Correlation with Amblyopia and Refractive Errors among Primary School Children.

Purpose:To determine the prevalence of color vision deficiency (CVD) and its correlation with amblyopia and refractive errors among primary school children.Methods:In this population-based cross-sectional study, 2160 children were selected from 36 primary schools; 60 students were from each school (10 students in each grade), with equal sex distribution. A complete eye examination including refraction using a photorefractometer, determination of visual acuity (VA) and color vision using a Yang vision tester, and evaluation of ocular media opacity using a direct ophthalmoscope was performed. Children who could not answer at least 4 plates of the Ishihara color test were considered as color vision deficient subjects. Amblyopia was determined if pinhole VA was worse than 0.3 LogMAR (equal to 20/40).Results:The prevalence of CVD was 2.2% (95% CI: 1.5% to 3%) which was higher in male subjects (37 [3.5%] boys vs. 11 [1.0%] girls, P < 0.001). Mean VA was lower among students with CVD as compared to normal color vision children (P = 0.035) and amblyopia was observed in 8.3% (95% CI: 0.2% to 16.4%) of patients with CVD versus 2.1% (95% CI: 1.5% to 2.08%) of children with normal color vision perception (P = 0.005). A statistically significant correlation between lower VA and CVD was observed (P = 0.023).Conclusion:Although CVD was correlated with lower VA and amblyopia, there was no relationship between CVD and the type of amblyopia, refractive error, anisometropia or strabismus.

Color Vision Deficiency in Preschool Children: The Multi-Ethnic Pediatric Eye Disease Study

To determine the sex- and ethnicity-specific prevalence of color vision deficiency (CVD) in black, Asian, Hispanic, and non-Hispanic white preschool children. Population-based, cross-sectional study. The Multi-Ethnic Pediatric Eye Disease Study is a population-based evaluation of the prevalence of vision disorders in children in Southern California. A total of 5960 subjects 30 to 72 months of age were recruited for the study, of whom 4177 were able to complete color vision testing (1265 black, 812 Asian, 1280 Hispanic, and 820 non-Hispanic white). Color vision testing was performed using Color Vision Testing Made Easy color plates (Home Vision Care, Gulf Breeze, FL), and diagnostic confirmatory testing was performed using the Waggoner HRR Diagnostic Test color plates (Home Vision Care). Testability of color vision in preschool children between 30 and 72 months of age and prevalence of CVD stratified by age, sex, and ethnicity. Testability was 17% in children younger than 37 months of age, increasing to 57% in children 37 to 48 months of age, 89% in children 49 to 60 months of age, and 98% in children 61 to 72 months of age. The prevalence of CVD among boys was 1.4% for black, 3.1% for Asian, 2.6% for Hispanic, and 5.6% for non-Hispanic white children; the prevalence in girls was 0.0% to 0.5% for all ethnicities. The ethnic difference in CVD was statistically significant between black and non-Hispanic white children (P = 0.0003) and between Hispanic and non-Hispanic white children (P = 0.02). In boys, most CVD cases were either deutan (51%) or protan (34%); 32% were classified as mild, 15% as moderate, and 41% as severe. Testability for CVD in preschool children is high by 4 years of age. The prevalence of CVD in preschool boys varies by ethnicity, with the highest prevalence in non-Hispanic white and lowest in black children.

Prevalence of colour blindness in province of Vojvodina - Republic of Serbia

The absence of one or more receptor types in the eye leads to colour blindness. The frequency of this anomaly varies between populations but also within different regions of a country. The aim of the study is to determine the frequency of colour blindness in the region of Vojvodina-Republic of Serbia. The study includes data obtained in the investigations conducted during the period 1996-2009. The total number of subjects is 14125 (6847 males; 7278 females). The Ishihara plates are applied as a common methodological procedure. In total, the frequency of colour-blind males and females is 5.62% and 0.34%, respectively. As for a particular type of this deficiency, the results suggest that deutan deficiency prevails in relation to protan. Prevalence of colour blindness in all three regions of Vojvodina is very similar. The genetic heterogeneity of ethnic groups for this anomaly is relatively small. In comparison with earlier studies conducted in the region of Vojvodina, a slightly lower prevalence of daltonism is observed in the present population. The obtained results are within the limits set for European populations.

OCT determined macular thickness in diabetic retinopathy and relation to colour vision deficiency patterns

Background: Diabetic retinopathy is the most common cause of blindness in industrialised nations and the incidence of diabetes is expected to rise over the next 10 years. Early treatment of proliferative diabetic retinopathy and diabetic maculopathy improves visual outcome and with effective screening, blindness could be reduced. Patients suffering from diabetes mellitus show alterations in their colour perception. Colour vision testing provides a sensitive, non-invasive method to assess macular damage in diabetic retinopathy and any deterioration in colour vision often precedes changes in other clinical measures such as visual acuity and morphological changes. Optical coherence tomography (OCT) provides cross-sectional images of the retina, information concerning internal retinal structure as well as reproducible measurements of retinal thickness. Aims & Objective: This study was intended to examine the relationship between macular thickness on OCT (Optical coherence tomography) and colour vision deficiency patterns in diabetics. Material and Methods: A total of 100 patients with established diabetic retinopathy visiting hospital were examined and a detailed history of diabetes, duration and inability to differentiate colours was taken. Retinal examination for evidence of diabetic retinopathy and colour vision patterns on Ishihara colour vision chart were noted. OCT was performed on these patients. Results: 21% (21 out of 100) of patients under study showed a gross deficiency of red green pattern of colour blindness. The colour vision deficiency increased with increasing macular thickness. Macula thickness on OCT in subjects varied from 188 to 462 microns. The average macular thickness of patients with total colour vision deficiency was 290 microns that with red green was 274 micron and those without any colour vision deficiency was 228. Prevalence of colour vision deficiency increased with duration of diabetes and severity of retinopathy. Conclusion: Higher prevalence of red green colour blindness was observed in patients of diabetes with macular oedema. Impaired colour vision was more in patients with macular thickness above 228 micron.

Serum homocysteine as a risk factor in diabetic with colour vision deficiency and for developing retinopathy

Background: Diabetic retinopathy causes vascular complications of retina causing blindness. Macular edema is the crucial cause of visual impairment and may occur at any stage of diabetic retinopathy. Patients suffering from diabetes mellitus can show alterations in their colour perception. Colour vision testing provides a sensitive method to assess macular damage. Deterioration in colour vision often precedes changes in other clinical measures such as visual acuity and morphological changes. Elevated homocysteine levels play a causative role in inducing vascular endothelial cell damage and causing retinopathy in diabetics. Aims & Objective: This observational study was intended to examine if serum homocysteine is a risk factor for developing colour vision defects in diabetes and worsening of retinopathy. Material and Methods: A total of 92 patients with established diabetic retinopathy and having colour vision defects visiting hospital were examined and a detailed history of duration of diabetes was taken. Retinal examination for evidence of diabetic retinopathy and colour vision patterns on Ishihara colour vision chart were noted. OCT was performed on these patients. Results: 92 of patients with diabetic retinopathy under study had a gross colour vision deficiency. The average macular thickness on OCT of patients with total colour vision deficiency was 279 microns. Prevalence of colour vision deficiency increased with duration of diabetes and severity of retinopathy. The average serum homocysteine level in these patients was 21.98 μM/L which was above the normal range. Serum homocysteine levels ranged from 11.0 μM/L to 30.2 among males and 11.1to 41.0 in females. Conclusion: Higher prevalence of colour blindness was observed in patients of diabetes with macular oedema and high circulating serum homocysteine levels. Impaired colour vision was more in patients with average macular thickness of 228 micron and raised homocysteine levels thus suggesting it could be a possible risk factor.

Prevalence of Congenital Red-Green Color Vision Defects among Various Ethnic Groups of Students in Erbil City

The incidence of color blindness varies from race to race and in different geographical area. Since, there is no such report about the prevalence of color blindness in the Kurdistan region (North of Iraq), the present study had been conducted to find out the incidence of color blindness among preliminary, secondary and college students of Erbil city, Kurdistan region – Iraq. Participant’s (n=1856, 1275 males, 581 females, age group 7 to 25 years) color vision was tested by using Ishihara chart. Among 1275 male students, 108 students (8.47%) were found to be color blind: 42 of them showed deuteranomalia, 39 protanomalia, 20 deuteranopia and 7 protanopia. Among 581 female students, 8 females (1.37%) were found to be color blind: 5 of them showed protanomalia, 2 deuteranomalia and 1 deuteranopia. Data observed by Chi-square test showed there was no significant difference between ethnic groups of both male and female students. Studies on color blindness in Kurdistan region are very few; we hope this student-based investigation is meant to fill a gap in this field.

An Ethical Analysis of Color Blindness and Its Implications in the Workplace

COLOR BLINDNESS an ethical analysis of and its implications in the workplace David C. Shishido Eyes, ears, nose, mouth and skin -- The two photoreceptors in the human eye, the building blocks of vision, are rods and cones. While rods are crucial mediators of vision in low light conditions and allow perception of black versus white, the focus of this paper will be on cones, which actively contribute to color vision. Cone photoreceptor activity is the foundation to what most humans consider “vision” --cones vastly outnumber rods in terms of usage in day- to-day activities of which the majority occur in room light-level conditions. In order to best understand the nature of human vision, I will briefly outline the process by which sensory perception is relayed from the eye to the brain. Within cones (and rods) there exist light-sensitive molecules, or cone pigments, (Rhodopsin in rods) which help transmit neural signals of color identification to the brain. Cone pigments, otherwise known as visual pigments, are made of two components. The Vision “begins” when photons of light, reflected on objects, are absorbed by the eye. The 11-cis¬¬-retinal undergoes conformational change in reaction to absorption of these light-waves, activating the opsin proteins to trigger changes within the photoreceptor that relates the neural signals to the brain. Our understanding of opsin is the key component to color blindness because it is here where the root of color blindness begins. The opsin genes of red and green, the most commonly unrecognizable colors, are not only located adjacent to one another, but are also 98% identical. Research suggests that the similarities between red and green opsin genes caused homologous recombination throughout human evolution (Neitz, 2009). Most importantly, these recombinations have led to excess creation of red and green pigment genes, which ultimately lead to color blindness via the X chromosome. These genes can either be missing, damaged or in excess and because males have only one X chromosome, males are more likely than females to experience color blindness (functional genes on one of the two X chromosome in females is capable of providing the gene pigments necessary for color detection). G ender is only one of two disparities in the prevalence of color vision deficiency -- there is equally, if not greater, inequalities in terms of affected race. Color deficiency is most common in European males (at an 8.1% high, almost twice that of other groups such as Asian-American males at a 5.9% high) followed by Asian, African American and finally Native America males (Delpero 2005). Unsurprisingly, less than 1% of women are affected across all genders. While there B erkeley S cientific J ournal • C olors • F all 2012 • V olume 17 • I ssue 1 • 1 B S J the channels of sensory perception in the human body are vast and complex. Vision allows us to perceive shapes and understand the world around us. When stopping at a traffic light at night unable to identify the relative position of lights, red and green distinguishes whether to stop or go. Green versus ripe tomatoes and rare versus well-done steak prove difficult to distinguish in the kitchen. A day at the beach might result in overexposure to the sun without the necessary warning signs of bright red skin. These are just a few of the problems that color vision deficient individuals face in daily activities. Color identification is undoubtedly a crucial component in our perception of the world, and yet there are a vast amount of individuals who live with color identification deficiencies ranging from red and green to blue and yellow. In this paper I will offer an introduction of the origins of color blindness, provide insight as to the groups of individuals most impacted in terms of lifestyle and employment by its limitations, and discuss current and future technology available to compensate and hopefully cure color vision deficiency. first is a protein known as opsin, while the second is a chromophore known as 11-cis-retinal. While visual pigments share the same chromophore, the opsins are of greatest concern in this article because opsins vary across different types of cones. These play major roles in the determination of which colors the brain perceives.

Assessment of the Medmont C100 test for colour vision screening of male Saudi Arabians

Purpose: To assess the Medmont C100 test as a colour vision screening tool. Methods: One hundred and seventeen young male adults were screened with the Medmont C100, Ishihara plates, and the screening mode of the Oculus Anomaloscope tests. All subjects were tested under constant room illumination, namely that of a day light fluorescent lamp at 200 lux. Inclusion criteria were visual acuities (VA) of 20/20 or better with or without correction and absence of known ocular pathologies.Aided and unaided visual acuities were measured with the Snellen VA chart. Results: Five out of the117 subjects, were found to have red-green colour vision deficiency (CVD) with Ishihara and anomaloscope tests indicating a 4.7% CVD prevalence, while the Medmont C100 test yielded 33 cases of red-green deficiency indicating CVD prevalence of 28%. With the Ishihara test, all five subjects were identified as deutans, while the anomaloscope revealed three as deutans and two as protans, and the Medmont C100 test identified all 33 cases as protans. Conclusion: The Medmont C100 test yielded significantly higher prevalence of protan CVD compared with the Ishihara platesand Anomaloscope tests. These findings suggest that caution should be taken when using Medmont C100 test for colour vision screening as it tends togive more false positive results with bias for protans. (S Afr Optom 2011 70(1) 14-20)

Assessment of the Medmont C100 test for colour vision screening of male Saudi Arabians

Purpose: To assess the Medmont C100 test as a colour vision screening tool. Methods: One hundred and seventeen young male adults were screened with the Medmont C100, Ishihara plates, and the screening mode of the Oculus Anomaloscope tests. All subjects were tested under constant room illumination, namely that of a day light fluorescent lamp at 200 lux. Inclusion criteria were visual acuities (VA) of 20/20 or better with or without correction and absence of known ocular pathologies. Aided and unaided visual acuities were measured with the Snellen VA chart. Results: Five out of the 117 subjects, were found to have red-green colour vision deficiency (CVD) with Ishihara and anomaloscope tests indicating a 4.7% CVD prevalence, while the Medmont C100 test yielded 33 cases ofred-green deficiency indicating CVD prevalence of 28%. With the Ishihara test, all five subjects were identified as deutans, while the anomaloscope revealed three as deutans and two as pro-tans, and the Medmont C100 test identified all 33 cases as protans. Conclusion: The Medmont C100 test yielded significantly higher prevalence of protan CVD compared with the Ishihara platesand Anomaloscope tests. These findings suggest that caution should be taken when using Medmont C100 test for colour vision screening as it tends to give more false positive results with bias for pro-tans. (S Afr Optom 2011 70(1) 14-20)

P2-413 Assessment of refractive errors and colour vision by vision screening among school children in Shimla district of North India

IntroductionWHO introduced the global initiative for the elimination of avoidable blindness by the year 2020 known as “Vision 2020”. Refractive errors, is one of the priority areas for vision 2020...

Prevalence of Colour Blindness in Young Jordanians

Colour blindness is one of the common genetic disorders observed in all human populations. It is a sex-linked recessive trait. The genes are located on the X chromosome within the Xq28 band. 1,418 university students (1,200 female and 218 male) from Zarka Private University and the Hashemite University were randomly selected and tested for congenital red/green colour blindness, by using Ishihara pseudo-isochromatic colour plates. A total of 23 individuals were found to be colour blind. In females, 4 students (0.33%) were colour blind: 1 of them showed protanomalia, 1 protanopia and 2 deuteranomalia. In males, 19 students (8.72%) were colour blind: 4 showed protanomalia, 3 protanopia, 8 deuteranomalia and 4 deuteranopia. The allelic frequencies of the colour vision gene were found to be 0.087 in males, 0.003 in females and 0.016 in the total population. Studies on colour blindness in Jordan are very few; this population-based investigation is meant to fill a gap in this field.

Hypertension and Color Blindness in Young Men

Medical data from Selective Service registrants born from 1939 to 1941 were studied in Oregon and Colorado. Among 29,119 registrants with medical information (41.3% of all registrants), 1,073 (3.6%) had definite hypertension, and 1,226 (4.2%) had some type of color blindness. In both states, there was a highly significant association between the prevalence of hypertension and the prevalence of color blindness. Thus, definite hypertension was present in 6.0% of color clind individuals but in only 3.6% of those with unimparied color vision, while color blindness occurred in 6.8% with definite hypertension, in 5.8% with borderline hypertension, and in only 4.0% with normal blood pressure. The data did not differentiate among types of color blindness, and the reason for the association is not yet evident.