Testing Color Vision in Children

It is important to screen for acquired or hereditary color vision defects as early as possible. Color vision is a critical part of the early learning experience, and children who have color deficiencies may have difficulties compared to their peers if there is color-based schoolwork. It becomes important for career interests/goals for older children as some jobs may require normal color vision. Hereditary red-green deficiencies are X-linked and therefore affect approximately 8% of males and less than 1% of females. Acquired color vision defects and blue-yellow defects are rare in the pediatric population; therefore, these conditions will be discussed minimally in this chapter. Infants are able to discern color by 2-3 months of age, but accurate color naming may not develop until 4-6 years of age. Screening tests are sensitive, fast, and easy to administer. If a deficiency is suspected through screening, further testing must be evaluated in order to determine the type and severity of the color vision defect. Color vision is typically tested starting at age 3 years and up.

A study of morbidities among electronic equipment manufacturing workers in Goa

Background: Electronic equipment manufacturing units are among the most common industries all over the world. It involves a large amount of employees required for processing, manufacturing, building and setting up electronic equipments. Workers are usually sedentary and involve very less physical movement. Chronic illnesses are common among these sedentary workers of which most important are cardiovascular diseases, hypertension, obesity and diabetes. Considering the importance of the subject and the lack of published evidence on health status of electronic manufacturing workers, our study was done with an aim of assessing selected morbidities among electronic equipment manufacturing units in Goa.Methods: Our retrospective record based cross-sectional study was conducted over a period of one month in March 2019. The study was done in electronic equipment manufacturing workers. Data included sociodemographic details of the workers and details of periodic medical check-up. The data analysis was done using and analyzed using SPSS version 22. Chi square test was used to assess association between qualitative variables.Results: Among the 109 electronic manufacturing workers, it was observed that 10.1% (11) had obesity with a BMI >30, 24.8% (27) had hypertension (>140/90) and 31.2% (34) had diabetes mellitus with HbA1c >6.5. In addition, 24.8% (27) had far vision defect and 39.4% (43) had near vision defect. 42.2% (46) had abnormal lung function tests, 0.9% (1) had hearing disability and 4.6% (5) had abnormal ECG findings. Among male workers 0.9% (1) had elevated PSA levels, whereas all PAPs smear reports were normal among female workers.Conclusions: This study highlights the need of periodic medical check-up of the electronic manufacturing workers for timely detection and early management of their health problems.

A Novel Splice-Site Variant in CACNA1F Causes a Phenotype Synonymous with Åland Island Eye Disease and Incomplete Congenital Stationary Night Blindness

Background: CACNA1F-related disorders encompass progressive and non-progressive disorders, including Åland island eye disease and incomplete congenital stationary night blindness. These two X-linked disorders are characterized by nystagmus, color vision defect, myopia, and electroretinography (ERG) abnormalities. Ocular hypopigmentation and iris transillumination are reported only in patients with Åland island eye disease. Around 260 variants were reported to be associated with these two non-progressive disorders, with 19 specific to Åland island eye disease and 14 associated with both Åland island eye disease and incomplete congenital stationary night blindness. CACNA1F variants spread on the gene and further analysis are needed to reveal phenotype-genotype correlation. Case Report: A complete ocular exam and genetic testing were performed on a 13-year-old boy. A novel splice-site variant, c.4294-11C>G in intron 36 in CACNA1F, was identified at hemizygous state in the patient and at heterozygous state in his asymptomatic mother and explained the phenotype synonymous with Åland island eye disease and incomplete congenital stationary night blindness observed in the patient. Conclusion: We present a novel variant in the CACNA1F gene causing phenotypic and electrophysiologic findings indistinguishable from those of AIED/CSNB2A disease. This finding further expands the mutational spectrum and our knowledge of CACNA1F-related disease.

Colour vision defect among secondary school students in enugu, Nigeria: prevalence, pattern and impact

Aim: To determine the prevalence, pattern and impact of colour vision defects among public secondary school students in Enugu, Nigeria with a view to guiding the affected students on appropriate career choice. Methods: A descriptive cross-sectional study was carried out among students attending public secondary schools in Enugu-East Local Government Area, Enugu state. A total of 950 students (361 males, 589 females) were selected by multistage sampling. The students were assessed for colour vision using Ishihara 38 plate edition and Farnsworth D-15 colour caps. An interviewer-administered structured questionnaire was used to obtain the socio-demographic data and impact of colour vision on colour-related school tasks and activities of daily living. Data was analysed using statistical package foe social sciences, version 20. Result: The age of the students ranged from 10-20 years with mean age of 14.2 ± 1.9 years. Eleven (1.2%) students were found to have colour vision defect out of whom 9 were boys and 2 were girls, 6 (54.5%) were deutan and 5 (45.5%) were protan. No tritan defect was detected. Greater percentages of the students with colour vision defect had difficulties with colour-related school tasks and daily activities when compared to those with normal colour vision. Conclusion: Colour vision defect may affect students’ performance in colour-related school tasks and activities of daily living. Therefore, early detection of colour vision defect is important so as to guide in the choice of future career

COLOUR VISION IMPAIRMENT IN DIABETIC RETINOPATHY

Background & objectives: Colour vision defects associated with ocular disease have been reported since the 17th century. Objectives were to study prevalence of colour vision abnormalities associated with diabetic retinopathy & to study the type of colour vision defect associated with diabetic retinopathy.Methods: A longitudinal descriptive study was conducted.70 patients diagnosed with Diabetic Retinopathy were selected. Colour vision was tested by using Ishihara & HRR Pseudoisochromatic charts.Results: When Evaluated using HRR plates 29 (41.42%) patients were found to have colour vision impairment. Among them 20 (68.96%) patients had colour vision impairment of the blue-yellow axis purely & 3(10.34%) patients of red-green axis purely & 6(20.70%) patients of both axis. Interpretation & conclusions: Colour vision especially of the blue-Yellow axis was found to be affected in this study. Colour vision and visual testing can be used as cheap, quick, non-invasive, portable tool for screening of diabetic retinopathy.

A Clinical Study of Optic Disc Edema in a Tertiary Eye Center of Nepal

Purpose: To evaluate the etiology and clinical presentation of cases with optic disc edema presenting to a tertiary eye center of Nepal. Background: The etiology of optic disc edema ranges from relatively benign to potentially sight and life threatening conditions. Till date very few studies have been done on disc edema in Nepal. Method: The authors conducted a prospective, descriptive study at B.P. Koirala Lions Center for Ophthalmic Studies (BPKLCOS), Nepal. All cases with disc edema presenting to the out patient department (OPD) from January 1, 2014 to June 30, 2015 were included in the study. Results: Total 112 patients were included in the study, out of which diagnosis could be established in 99. The mean age of the patients was 32.54 ± 13.97 years with the majority being female. The most common cause of disc edema was idiopathic intracranial hypertension (IIH) (37.5%,). Majority of the patients complained of isolated diminution of vision (38.4%). Among the eyes affected, 78.3% had best corrected visual acuity (BCVA) 6/6-6/18, 36.6% had color vision defect and 31.4% had reduced contrast sensitivity. The most common visual field defect was isolated enlarged blind spot (39.7 %). Conclusion: IIH followed by optic neuritis (ON) are the most common causes of disc edema. Conditions with disc edema mainly affect the age group 21-40 years with females affected 2.5 times more than males. Visual acuity, color vision and contrast sensitivity are deranged in majority of cases of ON and normal in majority of cases of IIH.

The burden of color vision defect in Nepal – an iceberg phenomenon

Background: Color vision tests are routinely performed and are mandatory in most part of the world. However, in Nepal and many other developing countries, color vision may often be overlooked. We evaluated a possible burden of color vision in a group of patients who were specifically evaluated for a color vision defects. This study evalutes the awareness of color vision defect among the patients evaluated and highlights the importance of the color vision evaluation. Methods: A sequential group of 73 people from August to September 2017 specifically evalu­ated for color vision defect for recruitment of government employment were evaluated. Ishi­harapseudo-isochromatic plates and Farnsworth-Munsell Dichotomous D-15 test were used for screening. Mean and Standard deviation were used for descriptive analysis of the data. Results: Fifty-seven were male and sixteen were female. The mean age was 23 years (SD ± 3.7). On evaluation of the color vision defect, 9 (12.3%) were found to have total color vision defect (achromatopsia), 3 (4%)-red-green defect and 1(1%) with blue red defect. None of the patients had undergone color vision test at eye hospital previously. There were 4 patients who were registered drivers who had color vision defect. Conclusions: Color vision is an important part of the vision. It should not be ignored.All of the patients evaluated were found to be unware of their condition. Early detection of color vision defects in individuals, if possible, at school level can help them to determine their careers and future endeavors at early stage.