Ishihara Test Research Articles

Dyschromatopsia due to welding arcs: An underestimated occupational injury

Welders are at risk of developing dyschromatopsia, a color vision deficiency, due to occupational exposure, including welding arcs. This visual impairment can impact occupational safety and performance but has received limited attention in research. : This study aimed to investigate the prevalence and characteristics of defective color vision among welders exposed to welding arcs. A cross-sectional study was conducted with 52 male welders working in various industries. Demographic and occupational data were collected through a questionnaire. Color vision assessment was performed using Ishihara and Farnsworth Munsell test. Welding exposure data were collected through self-reporting and workplace observations. Chi-square test was used for data analysis. A p-value of less than 0.05 was considered statistically significant. The prevalence of defective color vision among welders was 15.4%. Age, gender, years of experience, and types of welding performed did not significantly influence the prevalence. Welders in the age group of 31-40 years showed a higher prevalence. Inadequate use of eye protection was identified as a barrier to preventing color vision impairments. Defective color vision is a prevalent occupational injury among welders exposed to welding arcs. The study underscores the importance of preventive measures, including proper eye protection and education programs, to reduce the risk of visual impairments and improve occupational safety. Further research is needed to understand the long-term consequences of welding arc exposure on color vision and its impact on worker performance.

Impact of blur on clinical and occupational colour vision test results.

To evaluate whether colour vision normal (CVN) adults pass two Fletcher-Evans (CAM) lantern tests and to investigate the impact of imposed blur on Ishihara, CAM lantern and computerised colour discrimination test (colour assessment and diagnosis test [CAD] and Cambridge colour test [CCT]) results. In a pilot experiment, 20 (16 CVN and 4 colour vision deficient [CVD]) participants with normal VA were tested with the CAM lantern. In the main experiment, the impact of imposed dioptric blur (up to +8.00 D) on visual acuity and the Ishihara test, CAM lantern, CAD and CCT was assessed for 15 CVN participants. CVN participants can fail the CAM lantern, with specificity of 81.25% (aviation mode) and 75% (clinical mode), despite following the test requirements of participants having at least 0.18 logMAR (6/9) in the better eye. With blur, test accuracy was affected. As expected, significant detrimental effects of blur on test results were found for logMAR VA and CAM lantern (aviation) with +1.00 D or higher. Ishihara, CAD and CCT results were not detrimentally affected until +8.00 D. Yellow-blue discrimination was more affected by blur for the CAD than the CCT, which was not explained by the different colour spaces used or vectors tested. False-positive findings on lantern colour vision tests with small apertures are likely to be increased in patients with blur due to uncorrected refractive error or ocular and visual pathway disease. Other colour vision tests with larger stimuli are more robust to blur.

Consumer willingness to pay (WTP) for beef based on color and price discounts

Discoloration of beef products leads retailers to offer discounts or discard beef products, as consumers tend to reject a brownish beef color. This practice contributes to retail food waste and inefficient resource allocation linked to beef production. The objective of this study was to investigate U.S. consumer preferences for beef color and price discounts. After an initial test for screen acuity regarding color perception using a condensed form the ishihara test, data on meat purchasing behavior as well as demographic information was collected for all participants. An additional part of the study undertook a hypothetical discrete choice experiment using digital photos of beef steaks with different meat color, price, and discount labels in retail packaging to examine consumer preferences, willingness to pay, and the effects of discount pricing. Results of a Mixed Logit Model based on choice data show that beef shoppers perceive, see, and prefer color nearly linearly across days of retail display. Consumers' willingness to pay was negative for 4, 7 and 9 days of retail display relative to day zero and decreased with an increase in discoloration. Results indicate that beef shoppers would have to be financially compensated for choosing a steak that was discolored after 9 days of retail display. However, male beef buyers exhibit weaker preferences for color and could be a target segment for promoting discolored beef products to reduce meat waste.

Investigation through Animal-Computer Interaction: A Proof-of-Concept Study for the Behavioural Experimentation of Colour Vision in Zoo-Housed Primates.

Zoos are an important repository of animals, which have a wide range of visual systems, providing excellent opportunities to investigate many comparative questions in sensory ecology. However, behavioural testing must be carried out in an animal welfare-friendly manner, which is practical for zoo staff. Here, we present a proof-of-concept study to facilitate behavioural research on the sensory ecology of captive primates. A system consisting of a tablet computer and an automated feeder connected wirelessly was developed and presented to captive primate species to evaluate interactions with and without previous training. A colour stimulus, analogous to the Ishihara test, was used to check the level of interaction with the device, supporting future studies on sensory ecology with zoo animals. Animals were able to use the system successfully and displayed signs of learning to discriminate between the visual stimuli presented. We identified no risk for small primates in their interactions with the experimental setup without the presence of keepers. The use of electronic devices should be approached with caution to prevent accidents, as a standard practice for environmental enrichment for larger animals (e.g., spider monkeys). In the long term, the system developed here will allow us to address complex comparative questions about the functions of different visual systems in captive animals (i.e., dichromatic, trichromatic, etc.).

Test time affects Farnsworth D15 outcomes in practiced, but not unpracticed, subjects with color vision deficiency.

Imposing a time limit on the Farnsworth D15 test may prevent patients from compromising the test. This study aimed to investigate the effect of test time on the Farnsworth D15 color vision test in unpracticed and practiced subjects and determine an optimal test time. Twenty-one subjects (mean/standard deviation age, 33.1/9.3 years) with a range of congenital color vision deficiency participated in the study. Pseudoisochromatic plate screening, Farnsworth D15, and anomaloscope testing were performed for classification purposes. At each of 2 visits, 10 trials of the Farnsworth D15 were performed with a range in test times from 30 seconds to 10 minutes. Between visits, subjects practiced the test. Major crossovers were used as the outcome measure. A repeated-measures analysis of variance compared the scores across trials. Post hoc Dunnett's testing analyzed the pairwise data. Although no significant difference in the mean number of major crossovers was found across the 10 trials for the first visit ( F (9, 180) = 1.30, p=0.24), a significant difference was found for the second visit ( F (9, 180) = 4.77, p<0.001). The range of mean number of major crossovers for the second visit was 1.71 to 5.1, with the 30-second trial resulting in the largest number of major crossovers and the longest trial resulting in the smallest number of major crossovers. Analysis showed that a 2-minute time limit resulted in a Farnsworth D15 outcome that would be expected based on the anomaloscope for a majority of subjects. In this study, test time was found to affect performance in practiced subjects but not in unpracticed subjects. Based on this study, we recommend enforcing a time limit of 2 minutes to discourage those who try to pass the Farnsworth D15 through practice. Additional measures, such as recording patient behavior, can also be taken.

Electroretinography in congenital nystagmus patients with a normal fundus examination.

To identify the ophthalmic causes of congenital nystagmus with normal eye examination by electroretinography (ERG). Retrospective observational study. We reviewed the medical records of patients younger than 6months of age who presented between June 2008 and November 2011 with nystagmus and no other neurological signs following an otherwise normal eye examination. A complete ophthalmic examination and ERG (Nicolet Bravo system; Nicolet Biomedial & RETIscan; Roland Instruments), fundus photography, and Ishihara color test were performed to identify any ophthalmic causes of congenital nystagmus. Thirty-three patients met the criteria. Rod dysfunction was diagnosed in 4 patients (12.1%), cone dysfunction in 2 patients (6.1%), and cone-rod dysfunction in 1 patient (3.0%). The results of ERG were negative in 2 patients (6.1%). Idiopathic infantile nystagmus was diagnosed in the remaining 24 patients (72.7%) based on their normal ERG examination. In Korean congenital nystagmus patients with a normal fundus examination, achromatopsia and Leber's congenital amaurosis are uncommon causes. ERG is needed to make a definite diagnosis and provide prognostic information in congenital idiopathic nystagmus patients with a normal fundus examination.

VISUAL OUTCOME OF TRAUMATIC OPTIC NEUROPATHYAFTER STEROID TREATMENT IN KARIADI HOSPITAL

Introduction: The occurrence of Traumatic Optic Neuropathy (TON) often occurs in the form of head injuries resulting from traffic accidents. TON is an important cause of impaired visual function which may be improved with steroid therapy. Objective: To determine the visual outcome in patients with TON treated with steroids in Kariadi Hospital, Semarang Methods: This research was a retrospective study. Thirty patients (20 males and 10 females) with TON in ophthalmology clinic, Kariadi Hospital Semarang between Januari 2019 and December 2020. Visual acuity, contrast sensitivity and color blindness test were included data from medical record. Steroid therapy were divided into 3 groups. Intraveous steroid injection alone, intravenous steroid followed with oral steroid, and oral steroid alone. The Wilcoxon and paired-t test as comparison test of pre-post therapy in one group and friedman test as comparison test in 3 groups. Results: There were 5 cases that received intravenous steroid, 18 cases received intravenous steroid with oral steroid, and 7 cases received oral steroid. There were difference visual acuity in intravenous steroid with oral steroid (p = 0.001), visual acuity in oral steroid (p = 0.017), and color blindness test in intravenous steroid with oral steroid in pre-post therapy groups (p = 0.036). There were no difference in visual acuity, color blindness test, and contrast sensitivity between pre-post therapy groups when compared between 3 groups (p= 0.692, p =0.368, p=0.273). Conclusion: Patients with TON had better visual outcome after treated with intravenous steroid followed with oral steroid.

A Compact Depth Separable Convolutional Image Filter for Clinical Color Perception Test

&lt;p&gt;Deep convolutional neural networks have achieved good performance in the application of computer vision, but there are also problems, such as a large amount of computation, time consuming, and high memory demand. In this paper, a depthwise separable convolution filter pruning method based on PCA is proposed. First, this paper uses depthwise separable convolution to replace the conventional convolution in ResNet to reduce the number of parameters and the amount of computation in the network. The specific operation process is to first use depthwise convolution to separate the spatial dimension to increase the network width and expand the range of feature extraction, and then use pointwise convolution to reduce the computational complexity of conventional convolution operation. Second, PCA is used to distinguish stacked similar filters and perform dimensionality reduction, which not only alleviates the dimensional disaster, but also achieves compression of data and minimizes information loss. Experimental results show that this method can significantly improve the calculation speed and accuracy of the deep convolutional neural network model, and further compress the model size. On the clinical Color Perception Test Chart, this method reduced the amount of model parameters and MACs on ResNet by about 91% while maintaining the test accuracy at about 95%. With almost no loss of accuracy, this method greatly shortened the running time of the model.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Validation of a New Digital and Automated Color Perception Test.

Although color vision deficiencies are very prevalent, there are no ideal methods for assessing color vision in all environments. We compared a new digital and automated method that quantifies color perception for the three protan, deutan, and tritan axes with two of the most commonly used color tests in daily practice: the Ishihara 38 plates test and the Farnsworth-Munsell 100-Hue test. One hundred patients underwent a triple examination composed of the new DIVE Color Test, the Ishihara test, and the Farnsworth-Munsell 100-Hue test. The DIVE Color Test was performed twice in forty participants to assess its repeatability. In the trichromatic group, the mean age stood at 20.57 ± 9.22 years compared with 25.99 ± 15.86 years in the dyschromatic group. The DIVE and Ishihara tests exhibited excellent agreement in identifying participants with color deficiency (Cohen's kappa = 1.00), while it was 0.81 when comparing DIVE and Farnsworth. The correlation between the global perception values of Farnsworth (TES) and DIVE (GCS) was 0.80. The repeatability of the DIVE Color Test was high according to Bland-Altman analysis with an intraclass correlation coefficient of 0.83. According to Ishihara, the DIVE Color Test proved to be an effective and reproducible tool for red-green color vision deficiency detection, capable of determining the severity of the defect in each of the three axes faster and more accurately than both Ishihara and Farnsworth.

A Comparative Study of the Sensitivity and Specificity of the Ishihara Test With Various Displays

Visual colour differentiation in clinical research requires colour-competent (CC) participants. The Ishihara colour charts (ICC) have established themselves as the standard for CC screening of colour vision deficiencies (CVD). However, the extent to which the results can be compared with a presentation of the colour charts on a smartphone display (SD) is currently unknown. The aim of this in vitro study was to determine the sensitivity and specificity of the Ishihara colour deficiency test depending on the presentation mode. Dental students (female n = 28; male n = 10; mean age, 23.5 ± 2.65 years; median age, 23.0 ± 13.0 years) evaluated 25 Ishihara test plates on their SD (n = 38) and/or a calibrated monitor (HP monitor, 22-inch; n = 18). The median size of the SD was 6.0 inches. Datasets with more than 2 failed charts were scored. When the Ishihara test charts were presented on a PC screen, the sensitivity was 94.4% and the specificity was 82.4% (0 mistakes: n = 14, <3 failures: n = 3, 14 false answers: n = 1). On the SD, a sensitivity of 96.0% and a specificity of 94.7% were calculated (89.5% were correct; 4 participants [10.5%] made <3 errors; and 1 participant made 21 errors). No significant difference between display modi (PC vs SD) was evaluated (P > .05). The presentation of ICC on an SD is useful and can be used for the investigation of a possible CVD of large groups. Comparable results to data projection can be achieved with a high degree of certainty. For CVD screening of larger groups (eg, students in preclinical training as part of CC training), the presentation of ICC on the SD can be used. This research was able to demonstrate that the sensitivity and specificity of the usual presentation method (Ishihara's booklet or data projection) is comparable.

Changes in Ocular Functions after Bariatric Surgery: A Cross-sectional Study

Introduction: Obesity is a critical problem worldwide, as it contributes to many pathological diseases. Therefore, Bariatric Surgery (BS) is considered an optimal treatment modality for achieving ideal weight. However, the eye and its functions can be affected after surgery due to the changes that occur throughout the body. Aim: To investigate and analyse visual functions following BS. Materials and Methods: This was a cross-sectional study conducted at Elite Hospital in Riyadh City, Saudi Arabia, from January 2023 to June 2023. A total of 16 subjects (32 eyes) were enrolled in the study. The subjects were categorised into three groups: preoperative BS (Group I), postoperative six months (Group II), and postoperative duration of one to two years (Group III). All participants underwent complete ophthalmological examinations, including Visual Acuity (VA) measurement using the Snellen chart, refractive error measurement by autorefractometer, colour vision testing using the Ishihara test, Intraocular Pressure (IOP) measurement, and anterior segment examination using a slit lamp. Additionally, a dryness assessment was performed using clinical tests. Finally, choroidal thickness and Retinal Nerve Fiber Layer (RNFL) measurements were obtained using Optical Coherence Tomography (OCT). Statistical analysis was performed using IBM Statistical Package for Social Sciences (SPSS) Software Grad Pack Base version 28.0. One-way Analysis of Variance (ANOVA) and Kruskal-Wallis tests were used to compare the mean values of the three groups. Post-hoc tests were employed for multiple comparisons between groups. The significance level was set at 5%. Results: The range of the participants’ ages was 24 to 47 years. It was revealed that Body Mass Index (BMI) was significantly influenced by the time elapsed since BS (p-value=0.04). In contrast, the effect of BS was not statistically significant between groups for both systolic and diastolic measurements (p-value&gt;0.05). Moreover, the automated Central Foveal Thickness (CFT) showed a statistically significant difference between groups, with p-values of 0.013 for the right eye (OD) and 0.016 for the left eye (OS). Although there was no statistical difference in the effect of BS on the OD Ganglion Cell Complex (GCC) (p-value=0.338), there was a significant effect on the OS GCC (p-value=0.03). Post-hoc analysis indicated that participants in Group I had a higher BMI than participants in Group III, with a p-value of 0.036. CFT was significantly increased in Group II OS compared to Group I (p-value=0.016). Group III showed a significantly higher GCC than Group II (p-value=0.028). There was a significant difference in Goldmann IOP among the three groups (p-value=0.009). Additionally, a negative correlation was found between the duration of BS and BMI (r=-0.615, p-value=0.011) as well as for systolic measurements (r=-0.592, p-value=0.016). A strong negative correlation was also observed between Goldmann IOP and BS, which was statistically significant for the OD (r=-0.788*, p-value&lt;0.001) but not for the OS (r=-0.346, p-value=0.189). There was a statistically significant difference in OD nasal choroidal thickness at 500 μm (p-value=0.03) and at 1000 μm (p-value=0.03) among the three groups. Conclusion: Hence, it can be concluded that some ocular functions were positively altered while others were negatively affected after BS. Choroidal thickness decreased in the six-month postsurgery group but increased in the one to two-year group. IOP decreased in the six-month postsurgery group and further decreased in the one to two-year group. CFT increased in the sixmonth group but decreased in the one to two-year postoperation group. GCC thickness decreased in the six-month group and increased in the one to two-year post-BS group. Measurement of such parameters could serve as a preoperative assessment, especially for glaucomatous and hypertensive individuals who are planning for future BS. These evaluations could also aid in the treatment of eye diseases after surgery. Additionally, normal individuals should undergo pre- and postoperative evaluations of their visual refraction, as this may be altered due to changes in posterior segment parameters, such as choroidal thickness. However, more studies are needed to validate these results.

Development and validation of a new colour vision screener: A multi‐centre study

Aims/Purpose: The detection of acquired and congenital colour vision deficiency is of importance in the clinic for the early detection of ocular disease and determination of occupational suitability. Conventional methods of colour vision screening often fail to pass all normals and/or correctly identify those with acquired and congenital colour vision deficiency. The Colour Vision Screener (CVS) test [1] was developed to utilize an improved understanding of colour vision mechanisms to overcome the limitations present in conventional colour screening methods. This study aimed to use a robust multi‐centre methodology to fully validate the CVS test.Methods: Over 400 participants, including 124 normal trichromats, 166 deutans and 62 protans, were recruited from 10 international Colour Assessment and Diagnosis (CAD) testing centres. Each participant completed the CVS and the CAD test with calibrated visual displays. The red/green (RG) and yellow/blue (YB) CVS test sensitivity and specificity were established. The RG statistics were compared to the ‘gold standard’ reference for screening for RG congenital colour vision deficiency—the Ishihara pseudoisochromatic plate test.Results: The CVS test correctly identified ~99.1% of normal trichromats. All subjects with congenital RG loss and acquired loss on top of congenital RG deficiency were identified as having abnormal colour vision by the CVS. The Ishihara test, based upon 0 errors on the first 25 plates of the 38‐plate edition, correctly identifies ~80.6% of normal trichromats and 99.5% of subjects with congenital RG loss.Conclusions: Data collected across 10 international CAD centres demonstrate that the CVS can achieve a high sensitivity without sacrificing specificity. This multi‐centre study demonstrates that the CVS is quick, efficient, and easy to use and allows for the rapid and reliable screening of congenital and acquired colour vision deficiencies in large populations.Reference1. Barbur JL, Rodriguez‐Carmona M, Evans BEW. Colour vision assessment‐3. An efficient, two‐step, colour assessment protocol. Colour Research &amp; Application 2021; 46: 33–45. https://doi.org/10.1002/col.22599

Breaking the mould: An essential need in optic neuritis management

Aims/Purpose: To present a clinical case to highlight the importance of ophthalmological examination in the management of optic neuritis.Methods: Case report.Results: A 45‐year‐old woman with Sjögren's syndrome and a family history of MS presents to the emergency department. She complains of decreased vision OD for the past 4 days, with exacerbated‐by‐eye‐movements retroocular pain and migraine‐like headache. BCVA is amaurosis OD and 1 OI, with right RAPD and no colour vision impairment in OI. Except for optic disc oedema with splinter haemorrhages in OD the rest of the ophthalmological examination is normal. RNFL‐OCT reveals thickening in the OD (220 μm/110 μm). Brain CT and laboratory tests, including D‐dimers, are normal. A LP is performed to rule out infectious causes is normal. Neurofilament and ESR are also normal. Brain and spinal MRI show no abnormalities. Due to the severity, methylprednisolone therapy is initiated. One week later, her symptoms are stable, except for headache and retroocular pain improvement. Upon reassessment, despite preserved BCVA and Ishihara in OI, an increase in RNFL thickening is noted in OI (120 μm), with partial arcuate defect in visual field. Anti‐MOG, AQP4 and a panel of autoantibodies including anti‐Ro and anti‐La, are still pending. Considering the bilateral involvement, plasma exchange therapy is initiated. 14 days after, BCVA OU has improved to 1, and the visual field and Ishihara test have normalized. RNFL thickening is still observed OU (161/120 μm) and there is persistent optic disc edema OD. Anti‐MOG are positive, AQP4‐Ab are negative, and both negative in CSF.Conclusions: The coexistence of other autoimmune diseases, can lead to attributing the ON to that disease rather than considering the neuroinflammatory aetiology, leading to delayed diagnosis. The detection of subclinical bilateral involvement was crucial in escalating the therapeutic regimen. Seropositivity is the confirmatory diagnostic marker, but in many centres, it may be difficult to obtain reliable biomarker data.

PEMERIKSAAN TEKANAN DARAH DAN TES BUTA WARNA PADA MAHASISWA BARU DI SALAH SATU PTS KOTA PALEMBANG TAHUN 2023

Background: Health examinations can be carried out at government or private laboratories or free health education institutions. A person's blood pressure is influenced by several factors, such as changes in body position and physical activity. However, color often causes problems for sufferers both in daily activities and when sufferers want to pursue higher education or apply for certain types of work. The aim is to provide blood pressure checks and color blindness tests for new students at PTS X Palembang City in 2023. Method: research using quantitative methods with a Cross Sectional research design, carried out at the PTS X Laboratory, Palembang City on September 7 2023. The research population was 96 students and the research sample was 96 students using total sampling technique, data collection using checklist sheets and data analysis using univariate and bivariate analysis. Results: Based on the results obtained from 96 students at PTS Blood pressure examination results were abnormal 51.0%, normal 49.0%. The color blindness test results, which were 1.0% color blind, were 99.0% normal. From the majors, the Public Health major got 57.3%, ATLM 42.7%. There is a significant relationship between the color blindness test and gender (p value 0.003 and OR 0.900). There was no relationship between gender, PTS major and blood pressure. There is no relationship between major and color blindness test. Conclusion: Blood pressure checks and especially color blindness should be given early so as not to affect learning achievement, educational paths and future career development. Keywords : Health Checkup, Blood pressure, Color blindness

Poster Session II: XR-based personalized active aid for color deficient observers.

In a previous study, Xu et al. (Optics Express, 2022) investigated the efficacy of active aid in the form of personalized image enhancement to increase color discrimination ability in color-deficient observers (CDO). The study parameterized severity of color deficiency, the wavelength shift of cone spectral fundamentals, and the spectral distribution of display primaries. The first parameter was derived by computing the confusion index of the CDO, employing a modified version of the FM-100 test (ZJU50Hue). The second parameter was determined via evaluation of a wavelength-shifted ZJU50Hue test on color-normal observers (CNO). The three parameters were used to model the gamut mapping between CNO and CDO. In this study, extended reality (XR) based modules were developed to acquire these parameters and consequently tailor the headset display to assist CDOs. We chose to implement the Cambridge color test over the ZJU50Hue test as threshold results along the protan, deutan, and tritan lines are more informative than a single confusion index. Preliminary results on a calibrated Varjo XR-3 headset suggest a high correlation between the standard CCT and our XR-based trivector test. As the calibration, simulation and modeling processes all take place in the same HMD, we intend to model the CNO-CDO gamut mapping into a post-process graphics shader to enhance the camera input of the XR-3 and perform a paper-based Ishihara test for evaluation of real-world color discrimination efficacy.

Comparison of Two Printed Pseudoisochromatic Tests for Color Vision Assessment.

The Waggoner PIP24 is a pseudoisochromatic test with a pattern similar to the Ishihara test. This study determined that the W-PIP24 can be used clinically to yield screening results (or sensitivity and specificity) comparable with the Ishihara. This study aimed to determine whether the W-PIP24 is equivalent to the Ishihara 38 edition pseudoisochromatic test in detecting red-green color vision defects. Also, the performance of each plate of the W-PIP24 in detecting the color vision defects relative to the Ishihara test was determined. Sixty-three individuals with congenital red-green color vision defects and 57 with normal trichromacy were recruited. Participants were tested with both the Ishihara and W-PIP24. The first-order agreement coefficients were calculated for the Ishihara and W-PIP24. The results were also analyzed using specificity, sensitivity, efficiency, and predictive pass and fail values. The agreement between the W-PIP24 and Ishihara test using the recommended criterion of using all plates was perfect. The sensitivity, specificity, predictive pass, and predictive fail were 1.00 (95% confidence interval, 0.94 to 1.00). This study showed that the W-PIP24 using a failure criterion of three or more errors on screening plates 1 to 15 is equivalent to the Ishihara test while screening for red-green color vision deficiency using a failure criterion of three or more errors on screening plates 1 to 17 of the Ishihara 38 edition.

Prevalence of Congenital Color Vision Deficiency in Southern Taiwan and Detection of Female Carriers by Visual Pigment Gene Analysis.

This study aimed to investigate the prevalence of color vision deficiencies (CVDs) and determine whether carriers could be detected by analyzing the visual pigment genes. Materials and Methods: The data of students who underwent routine CVD screening using the Ishihara color test in Kaohsiung, Southern Taiwan were analyzed. Furthermore, the DNA samples of 80 randomly selected females and four obligate carriers were analyzed. The most upstream genes, downstream genes, and the most downstream genes in the red/green pigment gene arrays were amplified separately using polymerase chain reaction (PCR), and exon 5 of each gene was analyzed. The prevalence of congenital red-green CVD in this study was 3.46% in males and 0.14% in females. The PCR analysis of the first gene, downstream gene, and last gene revealed normal patterns in 73 normal cases. Seven unusual patterns were detected in two proton carriers and five deutan carriers. Among the randomly selected females, 8.8% (7/80) were CVD carriers. The prevalence of CVD among male Taiwanese students in this study was 3.46%. Female carriers of congenital CVD can be identified by molecular analysis of the visual pigment genes. The proportion of CVD carriers among the randomly selected females was 8.8%, which was slightly higher than expected and further studies are warranted.

Why Should Red and Green Never Be Seen? Exploring Color Blindness Simulations as Tools to Create Chromatically Accessible Games

Video games have become an important aspect of modern culture, especially with the widespread use of mobile devices. Thus, it is important that video games are accessible to all people, but colorblind players are still affected by the use of colors in game interfaces. Some challenges of developing chromatically accessible games are the limited availability of colorblind test subjects and the importance of identifying and considering accessibility threats even in the early stages of development. Thus, digital simulations emerge as possible tools to increase accessibility and awareness. In this paper, we conducted three empirical studies that seek to verify the relationship between the identification of color accessibility problems by people with typical color vision using simulations and people with color blindness, in the context of mobile games. Results indicate concrete uses in which color blindness simulations give advantages to developers with typical vision in identifying chromatic accessibility issues in their games. Additionally, we discuss different possibilities for incorporating simulation tools, accessibility guidelines, and colorblind user participation into a realistic game design life cycle. We also discuss how the incorporation of simulation tools could be beneficial to foment the discussion of accessibility in game design studios.

The prevalence of red-green color vision deficiency and its related factors in an elderly population above 60 years of age.

To determine the prevalence of red-green (RG) color vision deficiency (CVD) in an elderly population and its related factors. This report is a part of the Tehran Geriatric Eye Study: a cross-sectional population-based study that was conducted on the elderly population (≥60y) of Tehran, Iran using multi-stage stratified random cluster sampling. All study participants underwent complete ocular examination, including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, and slit-lamp biomicroscopy. The color vision was tested using Ishihara plates with the near optical correction in place. Of the 3791 invitees, 3310 participated in the study. The data of 2164 individuals were analyzed after applying the exclusion criteria. The prevalence of R-G CVD was 3.73% (95%CI: 2.37%-5.09%) in the whole sample; the prevalence of protanomaly, protanopia, and deuteranopia was 1.51%, 1.76%, and 0.45%, respectively. The prevalence of R-G CVD was significantly higher in males than in females. The prevalence of RG CVD increased with advancing age from 2.91% in the age group 60-64y to 5.8% in the age group ≥80y (P=0.070). According to the multiple logistic regression model, male sex, and glaucoma were significantly related to RG CVD. Older age and hypertension also had a marginally significant relationship with RG CVD. Changes in color vision occur in the elderly due to the aging process and some physiological and pathological factors. Since the change in visual perception may affect the person's performance, this aspect of the visual system's function should also be taken into consideration in the examinations of the elderly.

The Prevalence of Congenital Color Vision Abnormality Among Patients Attending a Tertiary Eye Care Center in Southern India.

Background and objective Color vision abnormality is a condition where the faculty to identify one or more primary colors is either defective (anomalous) or absent (anopia). Occupations like armed forces, merchant navy, navigation, and police and fire services require normal color vision. There is a scarcity of data in the literature regarding the prevalence of congenital color vision abnormality in patients in South India. In light of this, the present study aimed to find the prevalence of congenital color vision abnormality in patients attending the Outpatient Department (OPD) at a tertiary eye care center in South India. Materials and methods This was a descriptive cross-sectional study conducted at a tertiary eye care center in South India from December 2014 to December 2016. Patients with a best-corrected visual acuity of 20/20, normal direct and consensual pupillary light reflex, normal anterior segment, and undilated fundus examination were included. Color vision was assessed using Ishihara pseudoisochromatic plates, American Optical Hardy-Rand-Rittler (AO HRR), and then the Farnsworth Munsell D15 arrangement test. All the results were tabulated and statistically analyzed. Statistical significance was calculated using the ANOVA test. Results A total of 371 patients were screened for color vision abnormality; 184 (49.59%) patients were males and 187 (50.40%)were females. Out of 371 patients in the study, 363(98.10%) had normal color vision while eight patients (2.16%) had color vision abnormality. Of the eight patients with color vision abnormalities, six (75%) had abnormal color vision on all three tests and two(25%) had an abnormality on only two tests (Ishihara and AO HRR). Out of 184 males in the study, eight patients (4.34%) had abnormal color vision while none of the 187 females had color vision abnormality; this difference was statistically significant (p=0.03). Conclusions Early diagnosis and providing education and awareness of this condition are necessary as part of guiding young people with regard to their career options and we recommend that all children should undergo color vision screening before entering high school.