Seeing Colours: Addressing Colour Vision Deficiency with Vision Augmentations using Computational Glasses

Colour vision deficiency is a common visual impairment that cannot be compensated for using optical lenses in traditional glasses, and currently remains untreatable. In our work, we report on research on Computational Glasses for compensating colour vision deficiency. While existing research only showed corrected images within the periphery or as an indirect aid, Computational Glasses build on modified standard optical see-through head-mounted displays and directly modulate the user’s vision, consequently adapting their perception of colours. In this work, we present an exhaustive literature review of colour vision deficiency compensation and subsequent findings; several prototypes with varying advantages—from well-controlled bench prototypes to less controlled but higher application portable prototypes; and a series of studies evaluating our approach starting with proving its efficacy, comparing to the state-of-the-art, and extending beyond static lab prototypes looking at real world applicability. Finally, we evaluated directions for future compensation methods for computational glasses.

A Hospital-Based Cross-Sectional Study to Estimate the Prevalence and Sex Distribution of Colour Vision Deficiency among School Going Children Attending a Tertiary Eye Care Center in Kolkata City, West Bengal, India

BACKGROUND Colour vision is a function of three types of cone pigments present in the retina. Colour vision deficiency is an important disorder of vision that may pose a handicap to the performance of an affected individual. The prevalence of colour blindness varies in different geographical areas. The identification and estimation of the prevalence of colour vision deficiency in school-going children will help to educate and guide the caregivers to help the children in selecting their profession. This study was done to estimate the prevalence, sex distribution, and types of colour vision deficiency among school-going children of 5 to 15 years. METHODS A cross-sectional observational study was done among 500 students to evaluate the colour vision during the period from 1st January 2018 to 30th June 2019 at the Regional Institute of Ophthalmology, Kolkata. Ishihara’s pseudo isochromatic colour vision chart 38th edition was used to assess the school children for colour vision status. The children who were found to be colour blind were further classified into degree and types of colour vision deficiency. RESULTS A total of 500 students (250 male & 250 female) of surrounding schools, in the age group of 5 years to 15 years, were screened. 480 students (96 %) had normal colour vision while 20 (4 %) students were found to have defective colour vision. Prevalence (4 %) for colour blindness was found to be higher in males (3.6 %) than females (0.4 %). It was observed that out of 20 (4 %) colour-blind subjects 3.6 % were protanopes and 0.4 % were deuteranopes. CONCLUSIONS The present study shows the prevalence of colour blindness found to be quite low (4 %) and more common in males (3.6 %) in comparison to females (0.4 %). Protanomaly (3.6 %) was more common than deuteranomaly (0.4 %). KEYWORDS Colour Blindness, Protanomaly, Deuteranomaly, School Children

Colour vision deficiency and sputum colour charts in COPD patients: an exploratory mixed methods study

This exploratory mixed method sub-study aimed to establish the impact of colour vision deficiency (CVD) on the usability of sputum colour charts in chronic obstructive pulmonary disease (COPD) patients. Participants with CVD and those with at risk of acquiring CVD were recruited for the study. Colour vision was tested using Chroma Test, which is a software program that analyses the tritan and protan colour contrast thresholds. Qualitative interviews (individual and focus groups) comprised of participants with COPD assessed for undiagnosed CVD, as well as a group with known CVD (with or without COPD). Interviews were analysed using the framework method. Refer to Protocol 1.In addition, a cross sectional study was conducted to determine the prevalence of CVD in The Health Improvement Network (THIN) using colour blind diagnostic read codes. A limitation of this could be failure of general practitioners to record CVD causing underreporting. Refer to Protocol 2.

Colour vision deficiency and sputum colour charts in COPD patients: an exploratory mixed-method study

Sputum colour may mark bacterial involvement in acute exacerbations of chronic obstructive pulmonary disease (COPD). However, whether colour vision deficiency (CVD) in COPD patients could impact the use of sputum colour charts as part of a guide to antibiotic use in exacerbations is unknown. This study used an exploratory mixed-method approach to establish the likelihood that COPD patients will be colour blind and whether this would result in the sputum colour chart being unusable in the context of the patients’ self-management of their condition. CVD is under-reported in primary care and comorbidities in COPD patients increase the risk of acquiring CVD. Participants diagnosed with CVD and risk of acquiring CVD were able to use the sputum colour charts. Colour charts are likely to be usable even in the context of undiagnosed CVD in COPD patients.

Awareness of colour blindness among nurses

The primary aim of this study is to find the awareness of colour blindness among 100 nurses in a hospital. Colour blindness or colour vision deficiency is the decreased ability to see and distinguish colours. It is one of the most common inherited disorders in human beings. It can also be acquired. It occurs due to the disorder or defect in the development of one or more of the three sets of colour sensing cones of the eye. There is no cure for colour vision deficiency. This study is a hospital-based descriptive cross-sectional study. Ethical clearance for the study was obtained from the institutional review board. A structured questionnaire on awareness of colour blindness was prepared. This was given to 100 nurses in the hospital. The data obtained were analysed with the help of a statistician. The result was that the nurses knew what colour blindness is, but they did not know much about the aetiology, transmission, treatment of the disorder. The nurses should be made more aware of colour blindness.

Screening of Colour Vision in Paediatric Population

The descriptive cross-sectional study was done to screen the children attending paediatric OPD of Saveetha Medical College and Hospital for colour vision deficiency and to find out the overall prevalence of CVD and compare the prevalence rate among males and females. One hundred seventy-five children in the age group 4 – 12 years attending paediatric OPD of Saveetha Medical College and Hospital were taken up for the study. Visual acuity and colour vision test using the Ishihara chart was conducted for all the children. Results were tabulated and statistically analysed. It was noted that 7 (4.14%) children were found to be colour deficient. Out of which 6 (7.68%) and 1 (1.10%) were Male and Female children respectively, Considering the religion, the higher prevalence of colour vision deficiency was found among Muslim children 4(14.8%) as compared to Hindu 2 (2.1%) and Christian 1 (2.1%) children. Early diagnosis of this defect helps them in minimising the potential problems they face in their everyday life, and enable them to make adaptive strategies to improve the quality of life and most importantly helps them in choosing appropriate professional choice in their career and creating awareness through education. Medical counselling will improve to reduce the occurrence of Colour Vision disorder.

Individualised Halo-Free Gradient-Domain Colour Image Daltonisation

Daltonisation refers to the recolouring of images such that details normally lost by colour vision deficient observers become visible. This comes at the cost of introducing artificial colours. In a previous work, we presented a gradient-domain colour image daltonisation method that outperformed previously known methods both in behavioural and psychometric experiments. In the present paper, we improve the method by (i) finding a good first estimate of the daltonised image, thus reducing the computational time significantly, and (ii) introducing local linear anisotropic diffusion, thus effectively removing the halo artefacts. The method uses a colour vision deficiency simulation algorithm as an ingredient, and can thus be applied for any colour vision deficiency, and can even be individualised if the exact individual colour vision is known.

The misuse of colour in science communication

The accurate representation of data is essential in science communication. However, colour maps that visually distort data through uneven colour gradients or are unreadable to those with colour-vision deficiency remain prevalent in science. These include, but are not limited to, rainbow-like and red–green colour maps. Here, we present a simple guide for the scientific use of colour. We show how scientifically derived colour maps report true data variations, reduce complexity, and are accessible for people with colour-vision deficiencies. We highlight ways for the scientific community to identify and prevent the misuse of colour in science, and call for a proactive step away from colour misuse among the community, publishers, and the press.